[Intraoperative virtual implant planning for volar plate osteosynthesis of distal radius fractures].
Franke, J; Vetter, S Y; Reising, K; Herrmann, S; Südkamp, N P; Grützner, P A; von Recum, J
2016-01-01
Digital planning of implants is in most cases conducted prior to surgery. The virtual implant planning system (VIPS) is an application developed for mobile C-arms, which assists the virtual planning of screws close to the joint line during surgery for treatment of distal radius fractures with volar plate osteosynthesis. The aim of this prospective randomized study was to acquire initial clinical experiences and to compare the VIPS method with the conventional technique. The study included 10 patients for primary testing and 30 patients with distal radius fractures of types A3, C1 and C2, divided in 2 groups. In the VIPS group, after placement of the plate and fracture reduction, a virtual 3D model of the plate was matched with the image of the plate from the fluoroscopic acquisition. Next, the length and position of the screws close to the joint line were planned on the virtual plate. The control group was treated with the same implant in the conventional way. Data were collected regarding screw replacement, fluoroscopy and operating room (OR) times. The VIPS group included six A3, one C1 and eight C2 fractures, while the control group consisted of six A3 and nine C2 fractures. Three screws were replaced in the VIPS group and two in the control group (p = 0.24). The mean intraoperative fluoroscopy time of the VIPS group amounted to 2.58 ± 1.38 min, whereas it was 2.12 ± 0.73 min in the control group (p = 0.26). The mean OR time in the VIPS group was 53.3 ± 34.5 minutes and 42.3 ± 8.8 min (p = 0.23) in the control group. The VIPS enables a precise positioning of screws close to joint line in the treatment of distal radius fractures; however, for routine use, further development of the system is necessary.
Fracture mechanisms and fracture control in composite structures
NASA Astrophysics Data System (ADS)
Kim, Wone-Chul
Four basic failure modes--delamination, delamination buckling of composite sandwich panels, first-ply failure in cross-ply laminates, and compression failure--are analyzed using linear elastic fracture mechanics (LEFM) and the J-integral method. Structural failures, including those at the micromechanical level, are investigated with the aid of the models developed, and the critical strains for crack propagation for each mode are obtained. In the structural fracture analyses area, the fracture control schemes for delamination in a composite rib stiffener and delamination buckling in composite sandwich panels subjected to in-plane compression are determined. The critical fracture strains were predicted with the aid of LEFM for delamination and the J-integral method for delamination buckling. The use of toughened matrix systems has been recommended for improved damage tolerant design for delamination crack propagation. An experimental study was conducted to determine the onset of delamination buckling in composite sandwich panel containing flaws. The critical fracture loads computed using the proposed theoretical model and a numerical computational scheme closely followed the experimental measurements made on sandwich panel specimens of graphite/epoxy faceskins and aluminum honeycomb core with varying faceskin thicknesses and core sizes. Micromechanical models of fracture in composites are explored to predict transverse cracking of cross-ply laminates and compression fracture of unidirectional composites. A modified shear lag model which takes into account the important role of interlaminar shear zones between the 0 degree and 90 degree piles in cross-ply laminate is proposed and criteria for transverse cracking have been developed. For compressive failure of unidirectional composites, pre-existing defects play an important role. Using anisotropic elasticity, the stress state around a defect under a remotely applied compressive load is obtained. The experimentally observed complex compressive failure modes, such as shear crippling and pure compressive fiber failure of fibers are explained by the predicted stress distributions calculated in this work. These fracture analyses can be damage tolerant design methodology for composite structures. The proposed fracture criteria and the corresponding critical fracture strains provide the designer with quantitative guidelines for safe-life design. These have been incorporated into a fracture control plan for composite structures, which is also described. Currently, fracture control plans do not exist for composite structures; the proposed plan is a first step towards establishing fracture control and damage tolerant design methodology for this important class of materials.
Jansen, Jesper; Schreurs, Ruud; Dubois, Leander; Maal, Thomas J J; Gooris, Peter J J; Becking, Alfred G
2018-04-01
Advanced three-dimensional (3D) diagnostics and preoperative planning are the first steps in computer-assisted surgery (CAS). They are an integral part of the workflow, and allow the surgeon to adequately assess the fracture and to perform virtual surgery to find the optimal implant position. The goal of this study was to evaluate the accuracy and predictability of 3D diagnostics and preoperative virtual planning without intraoperative navigation in orbital reconstruction. In 10 cadaveric heads, 19 complex orbital fractures were created. First, all fractures were reconstructed without preoperative planning (control group) and at a later stage the reconstructions were repeated with the help of preoperative planning. Preformed titanium mesh plates were used for the reconstructions by two experienced oral and maxillofacial surgeons. The preoperative virtual planning was easily accessible for the surgeon during the reconstruction. Computed tomographic scans were obtained before and after creation of the orbital fractures and postoperatively. Using a paired t-test, implant positioning accuracy (translation and rotations) of both groups were evaluated by comparing the planned implant position with the position of the implant on the postoperative scan. Implant position improved significantly (P < 0.05) for translation, yaw and roll in the group with preoperative planning (Table 1). Pitch did not improve significantly (P = 0.78). The use of 3D diagnostics and preoperative planning without navigation in complex orbital wall fractures has a positive effect on implant position. This is due to a better assessment of the fracture, the possibility of virtual surgery and because the planning can be used as a virtual guide intraoperatively. The surgeon has more control in positioning the implant in relation to the rim and other bony landmarks. Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Liu, A. F.
1974-01-01
A systematic approach for applying methods for fracture control in the structural components of space vehicles consists of four major steps. The first step is to define the primary load-carrying structural elements and the type of load, environment, and design stress levels acting upon them. The second step is to identify the potential fracture-critical parts by means of a selection logic flow diagram. The third step is to evaluate the safe-life and fail-safe capabilities of the specified part. The last step in the sequence is to apply the control procedures that will prevent damage to the fracture-critical parts. The fracture control methods discussed include fatigue design and analysis methods, methods for preventing crack-like defects, fracture mechanics analysis methods, and nondestructive evaluation methods. An example problem is presented for evaluation of the safe-crack-growth capability of the space shuttle crew compartment skin structure.
Mineback Stimulation Research Experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Warpinski, N.R.
The objective of the Mineback Stimulation Research Experiments is to improve hydraulic fracture stimulation technology by providing an in situ laboratory where basic processes and mechanisms that control and influence fracture propagation can be observed, measured and understood. While previous tests have been instrumental in providing an understanding of the mechanisms controlling fracture height, current experiments are focused on fluid flow through the created fracture and the associated pressure drops and crack widths. Work performed, accomplishments and future plans are presented. 7 refs., 2 figs.
Damage control and intramedullary nailing for long bone fractures in polytrauma patients.
Patka, Peter
2017-06-01
The early fracture treatment in patients with multiple injuries should be focused on damage control. The fracture type and its location, local soft tissue condition as well as the patient's physiological condition shall determine the time and type of fracture treatment. Prevention of local and systemic complications must be immediately considered and included in the treatment planning. The use of external fixator (ExFix), which will be replaced by IM-implants in most cases at a later stage, provides adequate temporary fracture stabilization with less collateral damage. Good clinical results can be expected in patients with long bone fractures if the principles of damage control surgery are applied and local complications are prevented through proper reduction, firm fixation, early soft tissue reconstruction, and early rehabilitation. Copyright © 2017 Elsevier Ltd. All rights reserved.
Environmental Justice analysis in Hydraulic Fracturing Analysis, June 13, 2011
This planning document describes the quality assurance/quality control activities and technical requirements that will be used during the research study, using an index-based approach to compare a nationally representative set of well sites fractured.
Multiwell fracturing experiments. [Nitrogen foam fracture treatment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Warpinski, N.
The objective of the Multiwell fracturing experiments is to test and develop the technology for the efficient stimulation of tight, lenticular gas sands. This requires basic understanding of: (1) fracture behavior and geometry in this complex lithologic environment, and (2) subsequent production into the created fracture. The intricate interplay of the hydraulic fracture with the lens geometry, the internal reservoir characteristics (fractures, reservoir breaks, etc.), the in situ stresses, and the mechanical defects (fracture, bedding, etc.) need to be defined in order to develop a successful stimulation program. The stimulation phase of the Multiwell Experiment is concerned with: (1) determiningmore » important rock/reservoir properties that influence or control fracture geometry and behavior, (2) designing fracture treatments to achieve a desired size and objectives, and (3) conducting post-treatment analyses to evaluate the effectiveness of the treatment. Background statement, project description, results and evaluation of future plans are presented. 5 refs., 2 figs., 2 tabs.« less
Wang, Huixiang; Wang, Fang; Newman, Simon; Lin, Yanping; Chen, Xiaojun; Xu, Lu; Wang, Qiugen
2016-08-01
Acetabular fracture surgery is amongst the most challenging tasks in the field of trauma surgery and careful preoperative planning is crucial for success. The aim of this paper is to describe the preliminary outcome of the utilization of an innovative computerized virtual planning system for acetabular fractures. 3D models of acetabular fractures and surrounding soft tissues from six patients were constructed from preoperative CT scans. A novel highly-automatic segmentation technique was performed on the 3D model to separate each fracture fragment, then 3D virtual reduction was performed. Additionally, the models were used to assess potential surgical approaches with reference to both the fracture and the surrounding soft tissues. The time required for virtual planning was recorded. After surgery, the virtual plan was compared to the real surgery with respect to surgical approach and reduction sequence. A Likert scale questionnaire was completed by the surgeons to evaluate their satisfaction with the system. Virtual planning was successfully completed in all cases. The planned surgical approach was followed in all cases with the planned reduction sequence followed completely in five cases and partially in one. The mean time required for virtual planning was 38.7min (range 21-57, SD=15.5). The mean time required for planning of B-type fractures was 25.0min (range 21-30, SD=4.6), of C-type fracture 52.3min (range 49-57, SD=4.2). The results of the questionnaire demonstrated a high level of satisfaction with the planning system. This study demonstrates that the virtual planning system is feasible in clinical settings with high satisfaction and acceptability from the surgeons. It provides a viable option for the planning of acetabular fracture surgery. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bakhireva, Ludmila N; Shainline, Michael R; Carter, Shelley; Robinson, Scott; Beaton, Sarah J; Nawarskas, James J; Gunter, Margaret J
2010-09-01
To examine the role of concurrent 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (statin) use and postmenopausal hormone therapy on osteoporosis-related fractures. Case-control study. Data Source. Large integrated health plan in New Mexico. Patients. Case patients were 1001 women with incident fractures of the hip, wrist, forearm, or spine that occurred between January 1, 2000, and December 31, 2005, and controls were 2607 women without fractures during the same time frame; both groups were selected from the same population of women aged 50 years or older who utilized health plan services during the study time frame. Postmenopausal hormone therapy use was classified as "current" (12 mo before index date) or "never or past." The risk of fractures was ascertained among continuous (> or = 80% medication possession ratio during 12 mo before the index date) and current (3 mo before index date) statin users relative to patients without hyperlipidemia who did not use lipid-lowering drugs. The interaction between statins and hormone therapy was examined in multivariable logistic regression. The association between statin use and fractures was examined separately among current and never or past hormone therapy users after controlling for other risk factors. Nineteen percent of the study participants were current hormone therapy users; 9.5% were current and 4.8% were continuous statin users. No association between continuous statin use and fractures was observed among never or past hormone therapy users (odds ratio [OR] 0.80, 95% confidence interval [CI] 0.53-1.22). In contrast, a strong protective effect (OR 0.19, 95% CI 0.04-0.87) was observed among women who concurrently used statins and hormone therapy for 1 year, independent of age; corticosteroid, bisphosphonate, thiazide diuretic, calcitonin, methotrexate, or antiepileptic drug use; chronic kidney disease; and Charlson comorbidity index. Concurrent statin use and hormone therapy may have a synergistic protective effect on skeletal fractures beyond the additive effect of each individual therapy.
Ward, M A; Xu, Y; Viswanathan, H N; Stolshek, B S; Clay, B; Adams, J L; Kallich, J D; Fine, S; Saag, K G
2013-04-01
We examined the association between osteoporosis treatment change and adherence, incident fractures, and healthcare costs among Medicare Advantage Prescription Drug (MAPD) plan members. Treatment change was associated with a small but significant increase in adherence, but was not associated with incident fracture or total healthcare costs. Overall adherence remained low. We examined the association between osteoporosis treatment change and adherence, incident fractures, and healthcare costs among MAPD plan members in a large US health plan. We conducted a retrospective cohort study of MAPD plan members aged≥50 years newly initiated on an osteoporosis medication between 1 January 2006 and 31 December 2008. Members were identified as having or not having an osteoporosis treatment change within 12 months after initiating osteoporosis medication. Logistic regression analyses and difference-in-difference (DID) generalized linear models were used to investigate the association between osteoporosis treatment change and (1) adherence to treatment, (2) incident fracture, and (3) healthcare costs at 12 and 24 months follow-up. Of the 33,823 members newly initiated on osteoporosis treatment, 3,573 (10.6%) changed osteoporosis treatment within 12 months. After controlling for covariates, osteoporosis treatment change was associated with significantly higher odds of being adherent (medication possession ratio [MPR]≥0.8) at 12 months (odds ratio [OR]=1.18) and 24 months (OR=1.13) follow-up. However, overall adherence remained low (MPR=0.59 and 0.51 for the change cohort and MPR=0.51 and 0.44 for the no-change cohort at 12 and 24 months, respectively). Osteoporosis treatment change was not significantly associated with incident fracture (OR=1.00 at 12 months and OR=0.98 at 24 months) or total direct healthcare costs (p>0.4) in the DID analysis, but was associated with higher pharmacy costs (p<0.004). Osteoporosis treatment change was associated with a small but significant increase in adherence, but was not associated with incident fracture or total healthcare costs in the MAPD plan population. Overall adherence to therapy remained low.
Haptic computer-assisted patient-specific preoperative planning for orthopedic fractures surgery.
Kovler, I; Joskowicz, L; Weil, Y A; Khoury, A; Kronman, A; Mosheiff, R; Liebergall, M; Salavarrieta, J
2015-10-01
The aim of orthopedic trauma surgery is to restore the anatomy and function of displaced bone fragments to support osteosynthesis. For complex cases, including pelvic bone and multi-fragment femoral neck and distal radius fractures, preoperative planning with a CT scan is indicated. The planning consists of (1) fracture reduction-determining the locations and anatomical sites of origin of the fractured bone fragments and (2) fracture fixation-selecting and placing fixation screws and plates. The current bone fragment manipulation, hardware selection, and positioning processes based on 2D slices and a computer mouse are time-consuming and require a technician. We present a novel 3D haptic-based system for patient-specific preoperative planning of orthopedic fracture surgery based on CT scans. The system provides the surgeon with an interactive, intuitive, and comprehensive, planning tool that supports fracture reduction and fixation. Its unique features include: (1) two-hand haptic manipulation of 3D bone fragments and fixation hardware models; (2) 3D stereoscopic visualization and multiple viewing modes; (3) ligaments and pivot motion constraints to facilitate fracture reduction; (4) semiautomatic and automatic fracture reduction modes; and (5) interactive custom fixation plate creation to fit the bone morphology. We evaluate our system with two experimental studies: (1) accuracy and repeatability of manual fracture reduction and (2) accuracy of our automatic virtual bone fracture reduction method. The surgeons achieved a mean accuracy of less than 1 mm for the manual reduction and 1.8 mm (std [Formula: see text] 1.1 mm) for the automatic reduction. 3D haptic-based patient-specific preoperative planning of orthopedic fracture surgery from CT scans is useful and accurate and may have significant advantages for evaluating and planning complex fractures surgery.
This planning document describes the quality assurance/quality control activities and technical requirements that will be used during the research study. The goal of this project is to evaluate the potential impacts of large volume water withdrawals.
NASA Astrophysics Data System (ADS)
Li, J. C.; Gong, B.; Wang, H. G.
2016-08-01
Optimal development of shale gas fields involves designing a most productive fracturing network for hydraulic stimulation processes and operating wells appropriately throughout the production time. A hydraulic fracturing network design-determining well placement, number of fracturing stages, and fracture lengths-is defined by specifying a set of integer ordered blocks to drill wells and create fractures in a discrete shale gas reservoir model. The well control variables such as bottom hole pressures or production rates for well operations are real valued. Shale gas development problems, therefore, can be mathematically formulated with mixed-integer optimization models. A shale gas reservoir simulator is used to evaluate the production performance for a hydraulic fracturing and well control plan. To find the optimal fracturing design and well operation is challenging because the problem is a mixed integer optimization problem and entails computationally expensive reservoir simulation. A dynamic simplex interpolation-based alternate subspace (DSIAS) search method is applied for mixed integer optimization problems associated with shale gas development projects. The optimization performance is demonstrated with the example case of the development of the Barnett Shale field. The optimization results of DSIAS are compared with those of a pattern search algorithm.
A visual servo-based teleoperation robot system for closed diaphyseal fracture reduction.
Li, Changsheng; Wang, Tianmiao; Hu, Lei; Zhang, Lihai; Du, Hailong; Zhao, Lu; Wang, Lifeng; Tang, Peifu
2015-09-01
Common fracture treatments include open reduction and intramedullary nailing technology. However, these methods have disadvantages such as intraoperative X-ray radiation, delayed union or nonunion and postoperative rotation. Robots provide a novel solution to the aforementioned problems while posing new challenges. Against this scientific background, we develop a visual servo-based teleoperation robot system. In this article, we present a robot system, analyze the visual servo-based control system in detail and develop path planning for fracture reduction, inverse kinematics, and output forces of the reduction mechanism. A series of experimental tests is conducted on a bone model and an animal bone. The experimental results demonstrate the feasibility of the robot system. The robot system uses preoperative computed tomography data to realize high precision and perform minimally invasive teleoperation for fracture reduction via the visual servo-based control system while protecting surgeons from radiation. © IMechE 2015.
Zeng, Canjun; Xing, Weirong; Wu, Zhanglin; Huang, Huajun; Huang, Wenhua
2016-10-01
Treatment of acetabular fractures remains one of the most challenging tasks that orthopaedic surgeons face. An accurate assessment of the injuries and preoperative planning are essential for an excellent reduction. The purpose of this study was to evaluate the feasibility, accuracy and effectiveness of performing 3D printing technology and computer-assisted virtual surgical procedures for preoperative planning in acetabular fractures. We hypothesised that more accurate preoperative planning using 3D printing models will reduce the operation time and significantly improve the outcome of acetabular fracture repair. Ten patients with acetabular fractures were recruited prospectively and examined by CT scanning. A 3-D model of each acetabular fracture was reconstructed with MIMICS14.0 software from the DICOM file of the CT data. Bone fragments were moved and rotated to simulate fracture reduction and restore the pelvic integrity with virtual fixation. The computer-assisted 3D image of the reduced acetabula was printed for surgery simulation and plate pre-bending. The postoperative CT scan was performed to compare the consistency of the preoperative planning with the surgical implants by 3D-superimposition in MIMICS14.0, and evaluated by Matta's method. Computer-based pre-operations were precisely mimicked and consistent with the actual operations in all cases. The pre-bent fixation plates had an anatomical shape specifically fit to the individual pelvis without further bending or adjustment at the time of surgery and fracture reductions were significantly improved. Seven out of 10 patients had a displacement of fracture reduction of less than 1mm; 3 cases had a displacement of fracture reduction between 1 and 2mm. The 3D printing technology combined with virtual surgery for acetabular fractures is feasible, accurate, and effective leading to improved patient-specific preoperative planning and outcome of real surgery. The results provide useful technical tips in planning pelvic surgeries. Copyright © 2016 Elsevier Ltd. All rights reserved.
Geriatric hip fracture management: keys to providing a successful program.
Basu, N; Natour, M; Mounasamy, V; Kates, S L
2016-10-01
Hip fractures are a common event in older adults and are associated with significant morbidity, mortality and costs. This review examines the necessary elements required to implement a successful geriatric fracture program and identifies some of the barriers faced when implementing a successful program. The Geriatric Fracture Center (GFC) is a treatment model that standardizes the approach to the geriatric fracture patient. It is based on five principles: surgical fracture management; early operative intervention; medical co-management with geriatricians; patient-centered, standard order sets to employ best practices; and early discharge planning with a focus on early functional rehabilitation. Implementing a geriatric fracture program begins with an assessment of the hospital's data on hip fractures and standard care metrics such as length of stay, complications, time to surgery, readmission rates and costs. Business planning is essential along with the medical planning process. To successfully develop and implement such a program, strong physician leadership is necessary to articulate both a short- and long-term plan for implementation. Good communication is essential-those organizing a geriatric fracture program must be able to implement standardized plans of care working with all members of the healthcare team and must also be able to foster relationships both within the hospital and with other institutions in the community. Finally, a program of continual quality improvement must be undertaken to ensure that performance outcomes are improving patient care.
Wang, Guang-Ye; Huang, Wen-Jun; Song, Qi; Qin, Yun-Tian; Liang, Jin-Feng
2016-12-01
Acetabular fractures have always been very challenging for orthopedic surgeons; therefore, appropriate preoperative evaluation and planning are particularly important. This study aimed to explore the application methods and clinical value of preoperative computer simulation (PCS) in treating pelvic and acetabular fractures. Spiral computed tomography (CT) was performed on 13 patients with pelvic and acetabular fractures, and Digital Imaging and Communications in Medicine (DICOM) data were then input into Mimics software to reconstruct three-dimensional (3D) models of actual pelvic and acetabular fractures for preoperative simulative reduction and fixation, and to simulate each surgical procedure. The times needed for virtual surgical modeling and reduction and fixation were also recorded. The average fracture-modeling time was 45 min (30-70 min), and the average time for bone reduction and fixation was 28 min (16-45 min). Among the surgical approaches planned for these 13 patients, 12 were finally adopted; 12 cases used the simulated surgical fixation, and only 1 case used a partial planned fixation method. PCS can provide accurate surgical plans and data support for actual surgeries.
Stress-Induced Fracturing of Reservoir Rocks: Acoustic Monitoring and μCT Image Analysis
NASA Astrophysics Data System (ADS)
Pradhan, Srutarshi; Stroisz, Anna M.; Fjær, Erling; Stenebråten, Jørn F.; Lund, Hans K.; Sønstebø, Eyvind F.
2015-11-01
Stress-induced fracturing in reservoir rocks is an important issue for the petroleum industry. While productivity can be enhanced by a controlled fracturing operation, it can trigger borehole instability problems by reactivating existing fractures/faults in a reservoir. However, safe fracturing can improve the quality of operations during CO2 storage, geothermal installation and gas production at and from the reservoir rocks. Therefore, understanding the fracturing behavior of different types of reservoir rocks is a basic need for planning field operations toward these activities. In our study, stress-induced fracturing of rock samples has been monitored by acoustic emission (AE) and post-experiment computer tomography (CT) scans. We have used hollow cylinder cores of sandstones and chalks, which are representatives of reservoir rocks. The fracture-triggering stress has been measured for different rocks and compared with theoretical estimates. The population of AE events shows the location of main fracture arms which is in a good agreement with post-test CT image analysis, and the fracture patterns inside the samples are visualized through 3D image reconstructions. The amplitudes and energies of acoustic events clearly indicate initiation and propagation of the main fractures. Time evolution of the radial strain measured in the fracturing tests will later be compared to model predictions of fracture size.
Sale, Joanna E M; Cameron, Cathy; Thielke, Stephen; Meadows, Lynn; Senior, Kevin
2017-06-01
Our objective was to ascertain whether the Theory of Planned Behaviour (TPB) explains patient intentions to use antiresorptive medication after a fracture. A qualitative study was conducted with English-speaking members of the Canadian Osteoporosis Patient Network (COPN) who had sustained a fragility fracture at 50+ years of age and were not taking antiresorptive medication at the time of that fracture. Questions during a 1-h telephone interview were guided by the domains of the TPB: they addressed the antecedent constructs regarding antiresorptive medication (attitudes, subjective norms, and perceived behavioural control) as well as intentions regarding antiresorptive medication use. We created a coding template a priori based on the TPB domains and applied this template to the interview data. Twenty-six eligible participants (24 females, 2 males) aged 51-89 completed an interview. The TPB appeared to be predictive of intentions in 19 (73%) participants. In the majority of participants where the TPB did not appear to be predictive (57%), a positive attitude toward antiresorptive medication was the most important antecedent variable in determining intentions. The TPB appeared to be predictive of intentions to use antiresorptive medication among individuals who had experienced a fragility fracture. Attitudes towards medication were especially important.
Shyu, Yea-Ing L; Liang, Jersey; Tseng, Ming-Yueh; Li, Hsiao-Juan; Wu, Chi-Chuan; Cheng, Huey-Shinn; Chou, Shih-Wei; Chen, Ching-Yen; Yang, Ching-Tzu
2013-08-01
Elderly patients with hip fracture have been found to benefit from subacute care interventions that usually comprise usual care with added geriatric intervention, early rehabilitation, and supported discharge. However, no studies were found on the effects of combining subacute care and health-maintenance interventions on health outcomes for elders with hip fracture. To compare the effects of an interdisciplinary comprehensive care programme with those of subacute care and usual care programmes on health-related quality of life (HRQoL) for elderly patients with hip fracture. Randomised controlled trial. A 3000-bed medical centre in northern Taiwan. Patients with hip fracture (N=299) were randomised into three groups: subacute care (n=101), comprehensive care (n=99), and usual care (n=99). Subacute care included geriatric consultation, continuous rehabilitation, and discharge planning. Comprehensive care consisted of subacute care plus health-maintenance interventions to manage depressive symptoms, manage malnutrition, and prevent falls. Usual care included only 1-2 in-hospital rehabilitation sessions, discharge planning without environmental assessment, no geriatric consultation, and no in-home rehabilitation. HRQoL was measured using the Medical Outcomes Study Short-Form 36 Taiwan version at 1, 3, 6, and 12 months after discharge. Participants in the comprehensive care group improved more in physical function, role physical, general health and mental health than those in the usual care group. The subacute care group had greater improvement in physical function, role physical, vitality, and social function than the usual care group. The intervention effects for both comprehensive and subacute care increased over time, specifically from 6 months after hip fracture onward, and reached a maximum at 12 months following discharge. Both comprehensive care and subacute care programmes may improve health outcomes of elders with hip fracture. Our results may provide a reference for health care providers in countries using similar programmes with Chinese/Taiwanese immigrant populations. Copyright © 2012 Elsevier Ltd. All rights reserved.
75 FR 35023 - Informational Public Meetings for Hydraulic Fracturing Research Study
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-21
... Fracturing Research Study AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: The... its proposed plan to study the relationship between hydraulic fracturing and drinking water. The... Agency's preliminary plans for study scope and design, and EPA will receive public comments on the...
Yoshii, Yuichi; Kusakabe, Takuya; Akita, Kenichi; Tung, Wen Lin; Ishii, Tomoo
2017-12-01
A three-dimensional (3D) digital preoperative planning system for the osteosynthesis of distal radius fractures was developed for clinical practice. To assess the usefulness of the 3D planning for osteosynthesis, we evaluated the reproducibility of the reduction shapes and selected implants in the patients with distal radius fractures. Twenty wrists of 20 distal radius fracture patients who underwent osteosynthesis using volar locking plates were evaluated. The 3D preoperative planning was performed prior to each surgery. Four surgeons conducted the surgeries. The surgeons performed the reduction and the placement of the plate while comparing images between the preoperative plan and fluoroscopy. Preoperative planning and postoperative reductions were compared by measuring volar tilt and radial inclination of the 3D images. Intra-class correlation coefficients (ICCs) of the volar tilt and radial inclination were evaluated. For the implant choices, the ICCs for the screw lengths between the preoperative plan and the actual choices were evaluated. The ICCs were 0.644 (p < 0.01) and 0.625 (p < 0.01) for the volar tilt and radial inclination in the 3D measurements, respectively. The planned size of plate was used in all of the patients. The ICC for the screw length between preoperative planning and actual choice was 0.860 (p < 0.01). Good reproducibility for the reduction shape and excellent reproducibility for the implant choices were achieved using 3D preoperative planning for distal radius fracture. Three-dimensional digital planning was useful to visualize the reduction process and choose a proper implant for distal radius fractures. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2646-2651, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
A summary of EPA's research relating to potential impacts of hydraulic fracturing on drinking water resources will be presented. Background about the study plan development will be presented along with an analysis of the water cycle as it relates to hydraulic fracturing processe...
NASA Technical Reports Server (NTRS)
1974-01-01
A monograph is presented which establishes structural design criteria and recommends practices to ensure the design of sound composite structures, including composite-reinforced metal structures. (It does not discuss design criteria for fiber-glass composites and such advanced composite materials as beryllium wire or sapphire whiskers in a matrix material.) Although the criteria were developed for aircraft applications, they are general enough to be applicable to space vehicles and missiles as well. The monograph covers four broad areas: (1) materials, (2) design, (3) fracture control, and (4) design verification. The materials portion deals with such subjects as material system design, material design levels, and material characterization. The design portion includes panel, shell, and joint design, applied loads, internal loads, design factors, reliability, and maintainability. Fracture control includes such items as stress concentrations, service-life philosophy, and the management plan for control of fracture-related aspects of structural design using composite materials. Design verification discusses ways to prove flightworthiness.
Computer assisted surgery in preoperative planning of acetabular fracture surgery: state of the art.
Boudissa, Mehdi; Courvoisier, Aurélien; Chabanas, Matthieu; Tonetti, Jérôme
2018-01-01
The development of imaging modalities and computer technology provides a new approach in acetabular surgery. Areas covered: This review describes the role of computer-assisted surgery (CAS) in understanding of the fracture patterns, in the virtual preoperative planning of the surgery and in the use of custom-made plates in acetabular fractures with or without 3D printing technologies. A Pubmed internet research of the English literature of the last 20 years was carried out about studies concerning computer-assisted surgery in acetabular fractures. The several steps for CAS in acetabular fracture surgery are presented and commented by the main author regarding to his personal experience. Expert commentary: Computer-assisted surgery in acetabular fractures is still initial experiences with promising results. Patient-specific biomechanical models considering soft tissues should be developed to allow a more realistic planning.
de Castro, Mara Antonio Monteiro; Poi, Wilson Roberto; de Castro, José Carlos Monteiro; Panzarini, Sônia Regina; Sonoda, Celso Koogi; Trevisan, Carolina Lunardelli; Luvizuto, Eloá Rodrigues
2010-06-01
Traumatic tooth injuries involve function and aesthetics and cause damage that range from minimal enamel loss to complex fractures involving the pulp tissue and even loss of the tooth crown. Technical knowledge and clinical experience are essential to establish an accurate diagnosis and provide a rational treatment. The purpose of this study was to evaluate the knowledge of Restorative Dentistry specialists about the management of crown and crown-root fractures based on treatment plans proposed by these professionals for these cases. A descriptive questionnaire was mailed to 245 Restorative Dentistry specialists with questions referring to their professional profile and the treatment plans they would propose for the management of crown and crow-root fractures resulting from dental trauma. One hundred and fifty-four questionnaires were returned properly filled. The data were subjected to descriptive statistics and the chi-square test was used to determine the frequency and the level of the significance among the variables. The analysis of data showed that in spite of having a specialist title, all interviewees had great difficulty in planning the treatments. As much as 42.8% of the participants were unable to treat all types of dental trauma. Complicated and uncomplicated crown-root fractures posed the greatest difficulties for the dentists to establish adequate treatment plans because these fractures require multidisciplinary knowledge and approach for a correct case planning and prognosis.
Alexander, Barbara M; Esswein, Eric J; Gressel, Michael G; Kratzer, Jerry L; Feng, H Amy; Miller, Arthur L; Cauda, Emanuele; Heil, Graeham
2018-01-01
The OSHA final rule on respirable crystalline silica (RCS) will require hydraulic fracturing companies to implement engineering controls to limit workers' exposure to RCS. RCS is generated by pneumatic transfer of quartz-containing sand during hydraulic fracturing operations. Chronic inhalation of RCS can lead to serious disease, including silicosis and lung cancer. NIOSH research identified at least seven sources where RCS aerosols were generated at hydraulic fracturing sites. NIOSH researchers developed an engineering control to address one of the largest sources of RCS aerosol generation, RCS escaping from thief hatches on the top of sand movers. The control, the NIOSH Mini-Baghouse Retrofit Assembly (NMBRA), mounts on the thief hatches. Unlike most commercially available engineering controls, the NMBRA has no moving parts and requires no power source. This article details the results of an evaluation of generation 3 of the NMBRA at a sand mine in Arkansas from May 19-21, 2015. During the evaluation, 168 area air samples were collected at 12 locations on and around a sand mover with and without the NMBRA installed. Analytical results for respirable dust and RCS indicated the use of the NMBRA effectively reduced concentrations of both respirable dust and RCS downwind of the thief hatches. Reductions of airborne respirable dust were estimated at 99+%; reductions in airborne RCS ranged from 98-99%. Analysis of bulk samples of the dust showed the likely presence of freshly fractured quartz, a particularly hazardous form of RCS. Use of an improved filter fabric and a larger area of filter cloth led to substantial improvements in filtration and pressures during these trials, as compared to the generation 2 NMBRA. Planned future design enhancements, including a weather cover, will increase the performance and durability of the NMBRA. Future trials are planned to evaluate the long-term operability of the technology.
NASA Astrophysics Data System (ADS)
Fairley, J. P., Jr.; Oyarzún L, R.; Villegas, G.
2015-12-01
Early theories of fluid migration in unsaturated fractured rock hypothesized that matrix suction would dominate flow up to the point of matrix saturation. However, experiments in underground laboratories such as the ESF (Yucca Mountain, NV) have demonstrated that liquid water can migrate significant distances through fractures in an unsaturated porous medium, suggesting limited interaction between fractures and unsaturated matrix blocks and potentially rapid transmission of recharge to the sat- urated zone. Determining the conditions under which this rapid recharge may take place is an important factor in understanding deep percolation processes in arid areas with thick unsaturated zones. As part of an on-going, Fondecyt-funded project (award 11150587) to study mountain block hydrological processes in arid regions, we are plan- ning a series of in-situ fracture flow injection tests in the Cerro Brillador/Mina Escuela, an underground laboratory and teaching facility belonging to the Universidad la Serena, Chile. Planning for the tests is based on an analytical model and curve-matching method, originally developed to evaluate data from injection tests at Yucca Mountain (Fairley, J.P., 2010, WRR 46:W08542), that uses a known rate of liquid injection to a fracture (for example, from a packed-off section of borehole) and the observed rate of seepage discharging from the fracture to estimate effective fracture aperture, matrix sorptivity, fracture/matrix flow partitioning, and the wetted fracture/matrix interac- tion area between the injection and recovery points. We briefly review the analytical approach and its application to test planning and analysis, and describe the proposed tests and their goals.
ERIC Educational Resources Information Center
AL Khayya, Hatem; El Geneidy, Moshera; Ibrahim, Hanaa; Kassem, Mohamed
2016-01-01
Hip fracture is considered one of the most fatal fractures for elderly people, resulting in increased morbidity and mortality and impaired functional capacity, particularly for basic and instrumental activities of daily living. The aim of this study was to determine the effect of implementing a discharge plan on functional abilities of geriatric…
Hydraulic-fracture diagnostic research. Final report, December 1989-December 1990
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fix, J.E.; Adair, R.G.; Clawson, G.E.
1992-05-01
The results of the research in microseismic methods to determine hydraulic fracture dimensions during the contract were significant. The GRI Hydraulic Fracture Test Site (HFTS) development planning was a major effort. Ten meetings of the Planning Team were coordinated and hosted. A statement of the HFTS mission, scope, objectives, and requirements was created. The primary objectives were to provide for interdisciplinary experiments on fracture modeling and fracture diagnostics. A Conceptual Plan for the HFTS was compiled by Teledyne Geotech and distributed at the Project Advisors Group meeting. An experiment at the Shell South Belridge Field in California was a directmore » analog of the HFTS. Multiple fracture stimulations were monitored from 3 wells with cemented-in geophones. Methods of handling and processing large data volumes in real time were established. The final fracture geometry did not fit the circular model. Fracture diagnostics were monitored at two GRI cooperative wells: the Enron S. Hogsback No. 13-8A and the Phillips Ward C No. 11. Theoretical studies indicate that crack waves might be used as an estimate of fracture length. After applying advanced signal enhancement techniques to low-frequency signals from 14 surveys, it was concluded that the data from presently available sondes is contaminated by sonde resonances.« less
Clarke, Shane; Bradley, Rachel; Simmonds, Bethany; Salisbury, Chris; Benger, Jonathan; Marques, Elsa; Greenwood, Rosemary; Shepstone, Lee; Robinson, Maria; Appleby-Fleming, John; Gooberman-Hill, Rachael
2014-09-03
Currently identification, and therefore, management of patients at risk of osteoporotic fracture in the UK is suboptimal. As the majority of patients who fracture have fallen, it follows that people who fall can usefully be targeted in any programme that aims to reduce osteoporotic fracture. Targeting vulnerable patients who are likely to benefit from intervention may help shift the management of fracture prevention into primary care, away from emergency departments. Paramedics who attend to patients who have fallen may be well placed to assess future fracture risk, using the Fracture Risk Assessment Tool (FRAX) and communicate that information directly to general practitioners (GPs). This feasibility study takes the form of a pragmatic, randomised controlled trial aimed at exploring and refining issues of study design, recruitment, retention, sample size and acceptability preceding a large-scale study with fracture as the end point. Patients (aged >50) who fall, call an ambulance, are attended by a study paramedic and give verbal consent will be asked FRAX and fall questions. Patients who subsequently formally consent to participation will be randomised to control (usual care) or intervention groups. Intervention will constitute transmission of calculated future fracture risk to the patients' GP with suitable, evidence-based recommendations for investigation or treatment. 3 months after the index fall, data (proportion of patients in each group undergoing investigation or starting new treatment, quality of life and health economic) will be collected and analysed using descriptive statistics. A nested qualitative study will explore issues of acceptability and study design with patients, paramedics and GPs. This protocol was approved by NRES Committee South Central Oxford C in October 2012. Research Ethics Committee ref.12/SC/0604. The study findings will be disseminated through peer-reviewed journals, conference presentations and local public events. A publication plan and authorship criteria have been preagreed. 36245726. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Samieirad, Sahand; Aboutorabzade, Mohammad-Reza; Tohidi, Elahe; Shaban, Baratollah; Khalife, Hussein; Salami, Hamid-Reza
2017-01-01
Background The epidemiology of facial injuries varies based on lifestyle, cultural background and socioeconomic status in different countries and geographic zones. This study evaluated the epidemiology of maxillofacial fractures and treatment plans in hospitalized patients in Northeast of Iran (2015-2016). Material and Methods In this retrospective study, the medical records of 502 hospitalized patients were evaluated in the Department of Maxillofacial Surgery in Kamyab Hospital in Mashhad, Iran. The type and cause of fractures and treatment plans were recorded in a checklist. Data were analyzed with Mann–Whitney test, chi-squared test and Fisher’s exact test, using SPSS 21. Results The majority of patients were male (80.3%). Most subjects were in 20-30-year age range (43.2%). The fractures were mostly caused by accidents, particularly motorcycle accidents (MCAs), and the most common site of involvement was the body of the mandible. There was a significant association between the type of treatment and age. In fact, the age range of 16-59 years underwent open reduction internal fixation (ORIF) more than other age ranges (P=0.001). Also, there was a significant association between gender and fractures (P=0.002). Conclusions It was concluded that patient age and gender and trauma significantly affected the prevalence of maxillofacial traumas, fracture types and treatment plans. This information would be useful for making better health policy strategies. Key words:Epidemiology, treatment, facial injuries, maxillofacial fractures, trauma. PMID:28809369
Fatigue and pain limit independent mobility and physiotherapy after hip fracture surgery.
Münter, Kristine H; Clemmesen, Christopher G; Foss, Nicolai B; Palm, Henrik; Kristensen, Morten T
2018-07-01
The patient's ability to complete their planned physiotherapy session after hip fracture surgery has been proposed as an independent predictor for achieving basic mobility independency upon hospital discharge. However, knowledge of factors limiting mobility is sparse. We therefore examined patient reported factors limiting ability to complete planned physiotherapy sessions as well as limitations for not achieving independency in basic mobility early after hip fracture surgery. A total of 204 consecutive patients with a hip fracture (mean (SD) age of 80 (9.9) years, 47 patients were admitted from a nursing home) were treated in accordance with a multimodal program. The Cumulated Ambulation Score was used to evaluate the patient's independency in three basic mobility activities: getting in and out of bed, sit-to-stand-to-sit from a chair and indoor walking. Pre-defined limitations; pain, motor blockade, dizziness, fatigue, nausea, acute cognitive dysfunction and "other limitations", for not achieving a full Cumulated Ambulation Score or inability to complete planned physiotherapy sessions were noted by the physiotherapist on each of the three first postoperative days. This period was chosen, because of its importance on how well the patients had regained their pre-fracture functional level. Fatigue and hip fracture-related pain were the most frequent reasons for patients not achieving an independent basic mobility level (> 85%) or not fully completing their planned physiotherapy (> 42%) on all three days. At hospital discharge (median day 10), only 54% of the patients had regained their pre-fracture basic mobility level. Based on the patient's perception, fatigue and pain are the most frequent limitations in not achieving independent basic mobility and not completing physiotherapy after hip fracture surgery. This raises questions whether multimodal peri-operative programs can be further optimized to enhance the early recovery of these frail patients. Implications for rehabilitation Early postoperative mobilization is essential for patients undergoing hip fracture surgery to regain the pre-fracture functional level, in not only the short but also in the long term. The most frequent reasons for not achieving an independent Cumulated Ambulation Score or completing physiotherapy, early after hip fracture surgery, are fatigue, pain, and the habitual cognitive status of patients. Knowledge concerning postoperative fatigue is important for rehabilitation professionals and should contribute as an essential factor when planning physiotherapy.
[APPLICATION OF COMPUTER-ASSISTED SURGICAL PLANNING IN SURGICAL TREATMENT OF ANKLE FRACTURES].
Xia, Shengli; Wang, Xiuhui; Fu, Beigang; Lu, Yaogang; Wang, Minghui
2015-12-01
To explore the clinical value of computer-assisted surgical planning in the treatment of ankle fractures. Between January 2012 and January 2014, open reduction and internal fixation were performed on 42 patients with ankle fractures. There were 22 males and 20 females with an average age of 52 years (range, 19-72 years). The causes were spraining injury (20 cases), traffic accident injury (14 cases), and falling from height injury (8 cases). The time from injury to operation was 5 hours to 12 days (mean, 2.5 days). All fractures were closed trimalleolar fractures. According to Lauge-Hansen classification, 25 cases were rated as supination extorsion type IV, 13 as pronation extorsion type IV, and 4 as pronation abduction type III. The preoperative planning was made by virtual reduction and internal fixation using Superimage software. The mean operation time was 93.7 minutes (range, 76-120 minutes). Delayed wound healing occurred in 1 case, and secondary healing was obtained after treatment; primary healing of incision was achieved in the other patients. Postoperative X-ray films and CT images showed anatomic reduction of fracture and good position of internal fixation. All patients were followed up 14.6 months on average (range, 9-27 months). The range of motion of the affected ankle was close to the normal side at 6-8 weeks. The mean fracture healing time was 13.1 weeks (range, 11-17 weeks). Degenerative change of the ankle joint was observed in 3 cases (7.1%) with manifestation of mild narrowing of joint space on the X-ray films at last follow-up. According to Baird-Jackson score system, the results were excellent in 24 cases, good in 13 cases, and fair in 5 cases, with an excellent and good rate of 88%. Computer-assisted surgical planning for ankle fractures can help surgeons identify type of ankle fractures and improve surgical scheme for guiding fracture reduction and selecting and placing implants, so good effectiveness can be obtained.
Du, Hailong; Hu, Lei; Li, Changsheng; He, Chunqing; Zhang, Lihai; Tang, Peifu
2015-03-01
Balancing reduction accuracy with soft-tissue preservation is a challenge in orthopaedics. Computer-assisted orthopaedic surgery (CAOS) can improve accuracy and reduce radiation exposure. However, previous reports have not summarized the fracture patterns to which CAOS has been applied. We used a CAOS system and a stereolithography model to define a new fracture classification. Twenty reduction tests were performed to evaluate the effectiveness of preoperative trajectory planning. Twenty tests ran automatically and smoothly. Only three slight scratches occurred. Seventy-six path points represented displacement deviations of < 2 mm (average < 1 mm) and angulation deviation of < 1.5°. Because of the strength of muscles, mechanical sensors are used to prevent iatrogenic soft-tissue injury. Secondary fractures are prevented mainly through preoperative trajectory planning. Based on our data, a 1 mm gap between the edges of fractures spikes is sufficient to avoid emergency braking from spike interference. Copyright © 2014 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Singaravelu, J.; Sundaresan, S.; Nageswara Rao, B.
2013-04-01
This article presents a methodology for evaluation of the proof load factor (PLF) for clamp band system (CBS) made of M250 Maraging steel following fracture mechanics principles.CBS is most widely used as a structural element and as a separation system. Using Taguchi's design of experiments and the response surface method (RSM) the compact tension specimens were tested to establish an empirical relation for the failure load ( P max) in terms of the ultimate strength, width, thickness, and initial crack length. The test results of P max closely matched with the developed RSM empirical relation. Crack growth rates of the maraging steel in different environments were examined. Fracture strength (σf) of center surface cracks and through-crack tension specimens are evaluated utilizing the fracture toughness ( K IC). Stress induced in merman band at flight loading conditions is evaluated to estimate the higher load factor and PLF. Statistical safety factor and reliability assessments were made for the specified flaw sizes useful in the development of fracture control plan for CBS of launch vehicles.
Carbide Derived Carbon Super Capacitor Application
NASA Astrophysics Data System (ADS)
Appelgate, James; Bauer, Dave; Quirin, James; Lofland, S. E.; Hettinger, J. D.; Heon, M.; Gogotsi, Y.
2010-02-01
Supercapacitors can be applied into many different fields from nano-robots to high density energy storage. Growing TiC films from a know recipe and removing the transition metal element, Titanium, by chlorination leaves a carbon film that can then be applied as an electrode in a super capacitor. The problem is when the Titanium is removed from the film the stress induced by this process causes the films to fracture into isolated islands. The islands allow electrons to travel across them every easily, but there is no transfer of electrons from island to island. We present results of an investigation of a technique control the location of the fractures and use them to our benefit. Ideally, we want to create them to fracture in parallel lines. To force these fractures into straight lines we will purchase substrates with thermal SiO2 created on the surface of Si. Using an etching process we will removed a channel of SiO2 the same as the thickness of the TiC film we plan on growing. These channels will allow the fractures to form in a correlated way creating a straight line. )
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haidar, S.; Rylance, M.; Tybero, G.
1996-12-31
Having completed both fracture treatments as discussed in a companion paper, this paper continues on to describe the post fracture shut-in, clean-up and well testing operations that took place on the Viking Wx exploration well 49/17-12. These operations involved the removal of Resin Coated Proppant (RCP) from the wellbore, via Coiled Tubing (CT), through the use of a specially designed jetting nozzle. The RCP pack stability at a concentration of 3.0 lb/ft{sup 2} (as per planned design) had already been tested in a flowback cell. The use of a Surface Read-Out (SRO) gauge, combined with gas, water and proppant flowmore » rates as well as the viscosity of fracturing fluids returns, enabled real time calculation of the drag forces, on the proppant pack, during clean-up. The flow rate, in the field, was controlled such that the calculated drag forces remained below those observed in the laboratory. Following the clean-up a flow and build-up test was conducted, to evaluate the fracture half length and fracture conductivity, from which a Pseudo-radial skin was calculated. The Non-Darcy effects in the fracture were also evaluated, and finally the short term and long term well deliverabilities were assessed.« less
Thomas, Thaddeus P.; Anderson, Donald D.; Willis, Andrew R.; Liu, Pengcheng; Marsh, J. Lawrence; Brown, Thomas D.
2010-01-01
Background Highly comminuted intra-articular fractures are complex and difficult injuries to treat. Once emergent care is rendered, the definitive treatment objective is to restore the original anatomy while minimizing surgically induced trauma. Operations that use limited or percutaneous approaches help preserve tissue vitality, but reduced visibility makes reconstruction more difficult. A pre-operative plan of how comminuted fragments would best be re-positioned to restore anatomy helps in executing a successful reduction. Methods In this study, methods for virtually reconstructing a tibial plafond fracture were developed and applied to clinical cases. Building upon previous benchtop work, novel image analysis techniques and puzzle solving algorithms were developed for clinical application. Specialty image analysis tools were used to segment the fracture fragment geometries from CT data. The original anatomy was then restored by matching fragment native (periosteal and subchondral) bone surfaces to an intact template, generated from the uninjured contralateral limb. Findings Virtual reconstructions obtained for ten tibial plafond fracture cases had average alignment errors of 0.39 (0.5 standard deviation) mm. In addition to precise reduction planning, 3D puzzle solutions can help identify articular deformities and bone loss. Interpretation The results from this study indicate that 3D puzzle solving provides a powerful new tool for planning the surgical reconstruction of comminuted articular fractures. PMID:21215501
Dynamic Response in Transient Stress-Field Behavior Induced by Hydraulic Fracturing
NASA Astrophysics Data System (ADS)
Jenkins, Andrew
Hydraulic fracturing is a technique which is used to exploit geologic features and subsurface properties in an effort to increase production in low-permeability formations. The process of hydraulic fracturing provides a greater surface contact area between the producing formation and the wellbore and thus increases the amount of recoverable hydrocarbons from within the reservoir. The use of this stimulation technique has brought on massive applause from the industry due to its widespread success and effectiveness, however the dynamic processes that take part in the development of hydraulic fractures is a relatively new area of research with respect to the massive scale operations that are seen today. The process of hydraulic fracturing relies upon understanding and exploiting the in-situ stress distribution throughout the area of study. These in-situ stress conditions are responsible for directing fracture orientation and propagation paths throughout the period of injection. The relative magnitude of these principle stresses is key in developing a successful stimulation plan. In horizontal well plan development the interpretation of stress within the reservoir is required for determining the azimuth of the horizontal well path. These horizontal laterals are typically oriented in a manner such that the well path lies parallel to the minimum horizontal stress. This allows for vertical fractures to develop transversely to the wellbore, or normal to the least principle stress without the theoretical possibility of fractures overlapping, creating the most efficient use of the fluid energy during injection. The orientation and magnitude of these in-situ stress fields however can be dynamic, controlled by the subsequent fracture propagation and redistribution of the surrounding stresses. That is, that as the fracture propagates throughout the reservoir, the relative stress fields surrounding the fractures may see a shift and deviate from their original direction or magnitude. These types of shifts are of great concern because they can impact subsequent fracture development causing non-uniform fracture propagation and the potential overlapping of fracture paths as they extend from the wellbore at the point of injection. The dynamics of stress variation that occur with respect to hydraulic fracturing is a somewhat new area of study. In order to accomplish the goals of this thesis and continue future research in this area a new transient model has been developed in order to asses these dynamic systems and determine their influence on fracture behavior. This applies the use of a fully coupled finite element method in 2-D using linear elastic fracture mechanics which is then expanded using displacement discontinuity to a cohesive zone model in 3-D. A static boundary element model was also used to determine stress fields surrounding static, predetermined fracture geometries. These models have been verified against analytical solutions for simple cases and are now being applied to more detailed case studies and analysis. These models have been briefly discussed throughout this thesis in order to give insight on their current capabilities and application as well as their future potential within this area of research. The majority of this work introduces transient stress field prediction to cases of single and multiple hydraulic fractures. The static assessment of these stresses is determined for verification of results to those found in publication which leads into these transient stress field variations. A new method has been developed and applied to the stress state prediction for the first time in a transient fracture model which is partly based upon a critical distance theory. These dynamic interactions can provide useful insight to pertinent issues within the petroleum and natural gas industry such as those to hydraulic fracturing fluid loss and induced seismic events, as well as to applications of efficiency and optimization of the stimulation treatment plan.
Alexander, Barbara M.; Esswein, Eric J.; Gressel, Michael G.; Kratzer, Jerry L.; Feng, H. Amy; King, Bradley; Miller, Arthur L.; Cauda, Emanuele
2016-01-01
Inhalation of respirable crystalline silica (RCS) is a significant risk to worker health during well completions operations (which include hydraulic fracturing) at conventional and unconventional oil and gas extraction sites. RCS is generated by pneumatic transfer of quartz-containing sand during hydraulic fracturing operations. National Institute for Occupational Safety and Health (NIOSH) researchers identified concentrations of RCS at hydraulic fracturing sites that exceed 10 times the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) and up to 50 times the NIOSH Recommended Exposure Limit (REL). NIOSH research identified at least seven point sources of dust release at contemporary oil and gas extraction sites where RCS aerosols were generated. NIOSH researchers recommend the use of engineering controls wherever they can be implemented to limit the RCS released. A control developed to address one of the largest sources of RCS aerosol generation is the NIOSH mini-baghouse assembly, mounted on the thief hatches on top of the sand mover. This manuscript details the results of a trial of the NIOSH mini-baghouse at a sand mine in Arkansas, November 18 – 21, 2013. During the trial, area air samples were collected at 12 locations on and around a sand mover with and without the mini-baghouse control installed. Analytical results for respirable dust and RCS indicate the use of the mini-baghouse effectively reduced both respirable dust and RCS downwind of the thief hatches. Reduction of airborne respirable dust ranged from 85% to 98%; reductions in airborne RCS ranged from 79% to 99%. A bulk sample of dust collected by the baghouse assembly showed the likely presence of freshly fractured quartz, a particularly hazardous form of RCS. Planned future design enhancements will increase the performance and durability of the mini-baghouse, including an improved bag clamp mechanism and upgraded filter fabric with a modified air-to-cloth ratio. Future trials are planned to determine additional respirable dust and RCS concentration reductions achieved through these design changes. PMID:27003622
This roadmap outlines EPA’s plans to build upon the Agency’s commitment to transparency & stakeholder engagement coordinated during the development of the Hydraulic Fracturing (HF) Study Plan & will help inform the 2014 HF study draft assessment report.
Wu, Xin-Bao; Wang, Jun-Qiang; Zhao, Chun-Peng; Sun, Xu; Shi, Yin; Zhang, Zi-An; Li, Yu-Neng; Wang, Man-Yi
2015-02-20
Old pelvis fractures are among the most challenging fractures to treat because of their complex anatomy, difficult-to-access surgical sites, and the relatively low incidence of such cases. Proper evaluation and surgical planning are necessary to achieve the pelvic ring symmetry and stable fixation of the fracture. The goal of this study was to assess the use of three-dimensional (3D) printing techniques for surgical management of old pelvic fractures. First, 16 dried human cadaveric pelvises were used to confirm the anatomical accuracy of the 3D models printed based on radiographic data. Next, nine clinical cases between January 2009 and April 2013 were used to evaluate the surgical reconstruction based on the 3D printed models. The pelvic injuries were all type C, and the average time from injury to reconstruction was 11 weeks (range: 8-17 weeks). The workflow consisted of: (1) Printing patient-specific bone models based on preoperative computed tomography (CT) scans, (2) virtual fracture reduction using the printed 3D anatomic template, (3) virtual fracture fixation using Kirschner wires, and (4) preoperatively measuring the osteotomy and implant position relative to landmarks using the virtually defined deformation. These models aided communication between surgical team members during the procedure. This technique was validated by comparing the preoperative planning to the intraoperative procedure. The accuracy of the 3D printed models was within specification. Production of a model from standard CT DICOM data took 7 hours (range: 6-9 hours). Preoperative planning using the 3D printed models was feasible in all cases. Good correlation was found between the preoperative planning and postoperative follow-up X-ray in all nine cases. The patients were followed for 3-29 months (median: 5 months). The fracture healing time was 9-17 weeks (mean: 10 weeks). No delayed incision healing, wound infection, or nonunions occurred. The results were excellent in two cases, good in five, and poor in two based on the Majeed score. The 3D printing planning technique for pelvic surgery was successfully integrated into a clinical workflow to improve patient-specific preoperative planning by providing a visual and haptic model of the injury and allowing patient-specific adaptation of each osteosynthesis implant to the virtually reduced pelvis.
Drilling and production aspects of horizontal wells in the Austin Chalk
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sheikholeslami, B.A.; Scholhman, B.W.; Seidel, F.A.
1991-07-01
This paper discusses testing of horizontal technology for use in the highly fractured Giddings oil field. Three short-and seven medium-radius wells were drilled successfully in the Austin Chalk formation. The paper discusses well plans, bottomhole assemblies, trajectory control, telemetry, mud systems, hydraulics, hole cleaning, casing design, cementing, problems encountered, formation evaluation, completions, and reservoir response.
Natoli, R M; Baer, M R; Bednar, M S
2016-05-01
Distal radius fractures are common injuries treated in a multitude of ways. One treatment paradigm not extensively studied is initial treatment by external fixation (EF) followed by conversion to open reduction internal fixation (ORIF). Such a paradigm may be beneficial in damage control situations, when there is extensive soft tissue injury, or when appropriate personnel/hospital resources are not available for immediate internal fixation. There is no increased risk of infection when converting EF to ORIF in the treatment of complex distal radius fractures when conversion occurs early or if EF pin sites are overlapped by the definitive fixation. Using an IRB approved protocol, medical records over nine years were queried to identify patients with distal radius fractures that had undergone initial EF and were later converted to ORIF. Charts were reviewed for demographic data, injury characteristics, operative details, time to conversion from EF to ORIF, assessment of whether the EF pin sites overlapped the definitive fixation, presence of infection after ORIF, complications, and occupational therapy measurements of range of motion and strength. In total, 16 patients were identified, only one of which developed an infection following conversion to ORIF. Fisher's exact testing showed that infection did not depend on open fracture, time to conversion of one week or less, presence of EF pin sites overlapping definitive fixation, fracture classification, high energy mechanism of injury, or concomitant injury to the DRUJ. Planned staged conversion from EF to ORIF for complex distal radius fractures does not appear to result in an increased rate of infection if conversion occurs early or if the EF pin sites are overlapped by definitive fixation. This treatment paradigm may be reasonable for treating complex distal radius fractures in damage control situations, when there is extensive soft tissue injury, or when appropriate personnel/hospital resources are not available for immediate internal fixation. IV, retrospective case series. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Fracture control of ground water flow and water chemistry in a rock aquitard.
Eaton, Timothy T; Anderson, Mary P; Bradbury, Kenneth R
2007-01-01
There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/S(s)) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies.
Fracture control of ground water flow and water chemistry in a rock aquitard
Eaton, T.T.; Anderson, M.P.; Bradbury, K.R.
2007-01-01
There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/Ss) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies. ?? 2007 National Ground Water Association.
Technical Presentation Session 6: Monitoring slides to presentation by Denbury on tracking water movement through fracture systems in the Barnett shale. This includes information on micro-seismic well evaluation, well plans, and a fracture map.
Leong, Natalie L; Buijze, Geert A; Fu, Eric C; Stockmans, Filip; Jupiter, Jesse B
2010-12-14
Malunion is the most common complication of distal radius fracture. It has previously been demonstrated that there is a correlation between the quality of anatomical correction and overall wrist function. However, surgical correction can be difficult because of the often complex anatomy associated with this condition. Computer assisted surgical planning, combined with patient-specific surgical guides, has the potential to improve pre-operative understanding of patient anatomy as well as intra-operative accuracy. For patients with malunion of the distal radius fracture, this technology could significantly improve clinical outcomes that largely depend on the quality of restoration of normal anatomy. Therefore, the objective of this study is to compare patient outcomes after corrective osteotomy for distal radius malunion with and without preoperative computer-assisted planning and peri-operative patient-specific surgical guides. This study is a multi-center randomized controlled trial of conventional planning versus computer-assisted planning for surgical correction of distal radius malunion. Adult patients with extra-articular malunion of the distal radius will be invited to enroll in our study. After providing informed consent, subjects will be randomized to two groups: one group will receive corrective surgery with conventional preoperative planning, while the other will receive corrective surgery with computer-assisted pre-operative planning and peri-operative patient specific surgical guides. In the computer-assisted planning group, a CT scan of the affected forearm as well as the normal, contralateral forearm will be obtained. The images will be used to construct a 3D anatomical model of the defect and patient-specific surgical guides will be manufactured. Outcome will be measured by DASH and PRWE scores, grip strength, radiographic measurements, and patient satisfaction at 3, 6, and 12 months postoperatively. Computer-assisted surgical planning, combined with patient-specific surgical guides, is a powerful new technology that has the potential to improve the accuracy and consistency of orthopaedic surgery. To date, the role of this technology in upper extremity surgery has not been adequately investigated, and it is unclear whether its use provides any significant clinical benefit over traditional preoperative imaging protocols. Our study will represent the first randomized controlled trial investigating the use of computer assisted surgery in corrective osteotomy for distal radius malunions. NCT01193010.
The Role of Forethought and Serendipity in Designing a Successful Hydrogeological Research Site
NASA Astrophysics Data System (ADS)
Shapiro, A. M.; Hsieh, P. A.
2008-12-01
Designing and implementing a successful hydrogeologic field research observatory requires careful planning among a multidisciplinary group of research scientists. In addition, a small team of research coordinators needs to assume responsibility for smoothly integrating the multidisciplinary experimental program and promoting the explanation of results across discipline boundaries. A narrow interpretation of success at these hydrogeologic observatories can be viewed as the completion of the field-based experiments and the reporting of results for the field site under investigation. This alone is no small task, given the financial and human resources that are needed to develop and maintain field infrastructure, as well as developing, maintaining, and sharing data and interpretive results. Despite careful planning, however, unexpected or serendipitous results can occur. Such serendipitous results can lead to new understanding and revision of original hypotheses. To fully evaluate such serendipitous results, the field program must collect a broad range of scientifically robust data-beyond what is needed to examine the original hypotheses. In characterizing ground water flow and chemical transport in fractured crystalline rock in the Mirror Lake watershed in central New Hampshire, unexpected effects of scale were observed for hydraulic conductivity and matrix diffusion. Contrary to existing theory, hydraulic conductivity at the site did not increase with scale, whereas the effective coefficient of matrix diffusion was found to increase with scale. These results came to light only after examination of extensive data from carefully designed hydraulic and chemical transport experiments. Experiments were conducted on rock cores, individual fractures and volumes of fractured rock over physical dimensions from meters to kilometers. The interpretation of this data yielded new insight into the effect of scale on chemical transport and hydraulic conductivity of fractured rock. Subsequent evaluation of experiments conducted at other fractured rock sites have showed similarities in hydraulic and chemical transport responses, allowing broader conclusions to be reached concerning geologic controls on ground water flow and chemical transport in fractured rock aquifers.
Verma, Nikhil; Singh, M P; Ul-Haq, Rehan; Rajnish, Rajesh K; Anshuman, Rahul
2017-08-01
The aim of present study is to evaluate the outcome of bone marrow instillation at the fracture site in fracture of intracapsular neck femur treated by head preserving surgery. This study included 32 patients of age group 18-50 years with closed fracture of intracapsular neck femur. Patients were randomized into two groups as per the plan generated via www.randomization.com. The two groups were Group A (control), in which the fracture of intracapsular neck femur was treated by closed reduction and cannulated cancellous screw fixation, and Group B (intervention), in which additional percutaneous autologous bone marrow aspirate instillation at fracture site was done along with cannulated cancellous screw fixation. Postoperatively the union at fracture site and avascular necrosis of the femoral head were assessed on serial plain radiographs at final follow-up. Functional outcome was evaluated by Harris hip score. The average follow-up was 19.6 months. Twelve patients in each group had union and 4 patients had signs of nonunion. One patient from each group had avascular necrosis of the femoral head. The average Harris hip score at final follow-up in Group A was 80.50 and in Group B was 75.73, which was found to be not significant. There is no significant role of adding on bone marrow aspirate instillation at the fracture site in cases of fresh fracture of intracapsular neck femur treated by head preserving surgery in terms of accelerating the bone healing and reducing the incidence of femoral head necrosis. Copyright © 2017 Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. Production and hosting by Elsevier B.V. All rights reserved.
An integer programming model for distal humerus fracture fixation planning.
Maratt, Joseph D; Peaks, Ya-Sin A; Doro, Lisa Case; Karunakar, Madhav A; Hughes, Richard E
2008-05-01
To demonstrate the feasibility of an integer programming model to assist in pre-operative planning for open reduction and internal fixation of a distal humerus fracture. We describe an integer programming model based on the objective of maximizing the reward for screws placed while satisfying the requirements for sound internal fixation. The model maximizes the number of bicortical screws placed while avoiding screw collision and favoring screws of greater length that cross multiple fracture planes. The model was tested on three types of total articular fractures of the distal humerus. Solutions were generated using 5, 9, 21 and 33 possible screw orientations per hole. Solutions generated using 33 possible screw orientations per hole and five screw lengths resulted in the most clinically relevant fixation plan and required the calculation of 1,191,975 pairs of screws that resulted in collision. At this level of complexity, the pre-processor took 104 seconds to generate the constraints for the solver, and a solution was generated in under one minute in all three cases. Despite the large size of this problem, it can be solved in a reasonable amount of time, making use of the model practical in pre-surgical planning.
Pediatric nasoorbitoethmoid fractures.
Liau, James Y; Woodlief, Justin; van Aalst, John A
2011-09-01
The pediatric craniofacial trauma literature largely focuses on the management of mandible fractures, with very little information focusing on pediatric midface fractures, specifically nasoorbitethmoid (NOE) fractures. Because the diagnosis and surgical treatment plan for adult NOE fractures is well established in the literature, the treatment algorithms for NOE are essentially a transfer of adult practices to pediatric patients. This article reviews the differences between the pediatric and adult facial skeleton and the pathology and presentation of NOE fractures in the pediatric craniomaxillofacial skeleton. It also presents the effects of NOE fractures on the growth and development of the pediatric facial skeleton and describes the current surgical management for NOE fractures.
[Effect of 3D printing technology on pelvic fractures:a Meta-analysis].
Zhang, Yu-Dong; Wu, Ren-Yuan; Xie, Ding-Ding; Zhang, Lei; He, Yi; Zhang, Hong
2018-05-25
To evaluate the effect of 3D printing technology applied in the surgical treatment of pelvic fractures through the published literatures by Meta-analysis. The PubMed database, EMCC database, CBM database, CNKI database, VIP database and Wanfang database were searched from the date of database foundation to August 2017 to collect the controlled clinical trials in wich 3D printing technology was applied in preoperative planning of pelvic fracture surgery. The retrieved literatures were screened according to predefined inclusion and exclusion criteria, and quality evaluation were performed. Then, the available data were extracted and analyzed with the RevMan5.3 software. Totally 9 controlled clinical trials including 638 cases were chosen. Among them, 279 cases were assigned to the 3D printing technology group and 359 cases to the conventional group. The Meta-analysis results showed that the operative time[SMD=-2.81, 95%CI(-3.76, -1.85)], intraoperative blood loss[SMD=-3.28, 95%CI(-4.72, -1.85)] and the rate of complication [OR=0.47, 95%CI(0.25, 0.87)] in the 3D printing technology were all lower than those in the conventional group;the excellent and good rate of pelvic fracture reduction[OR=2.09, 95%CI(1.32, 3.30)] and postoperative pelvic functional restoration [OR=1.94, 95%CI(1.15, 3.28) in the 3D printing technology were all superior to those in the conventional group. 3D printing technology applied in the surgical treatment of pelvic fractures has the advantage of shorter operative time, less intraoperative blood loss and lower rate of complication, and can improve the quality of pelvic fracture reduction and the recovery of postoperative pelvic function. Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.
Reesink, Heidi L
2017-08-01
Foals are susceptible to many of the same types of fractures as adult horses, often secondary to external sources of trauma. In addition, some types of fractures are specific to foals and occur routinely in horses under 1 year of age. These foal-specific fractures may be due to the unique musculoskeletal properties of the developing animal and may present with distinct clinical signs. Treatment plans and prognoses are tailored specifically to young animals. Common fractures not affecting the long bones in foals are discussed in this article, including osteochondral fragmentation, proximal sesamoid bone fractures/sesamoiditis, and distal phalanx fractures. Copyright © 2017 Elsevier Inc. All rights reserved.
3D surgical printing and pre contoured plates for acetabular fractures.
Chana-Rodríguez, Francisco; Mañanes, Rubén Pérez; Rojo-Manaute, José; Gil, Pablo; Martínez-Gómiz, José María; Vaquero-Martín, Javier
2016-11-01
We describe the methodical and possibilities of 3D surgical printing in preoperative planning of acetabular fractures showing a case of a 45-year-old with an associated transverse fracture of the left acetabulum with posterior wall fracture, with multiple fragments, and posterior ipsilateral hip dislocation, defending the do it your-self mode. Copyright © 2016 Elsevier Ltd. All rights reserved.
The overall purpose of this study is to elucidate the relationship, if any, between hydraulic fracturing and drinking water resources. More specifically, the study has been designed to assess the potential impacts of hydraulic fracturing on drinking water resources and to identif...
Final Plan to Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources
The overall purpose of this study is to elucidate the relationship, if any, between hydraulic fracturing and drinking water resources. More specifically, the study has been designed to assess the potential impacts of hydraulic fracturing on drinking water resources and to identif...
Merema, B J; Kraeima, J; Ten Duis, K; Wendt, K W; Warta, R; Vos, E; Schepers, R H; Witjes, M J H; IJpma, F F A
2017-11-01
An innovative procedure for the development of 3D patient-specific implants with drilling guides for acetabular fracture surgery is presented. By using CT data and 3D surgical planning software, a virtual model of the fractured pelvis was created. During this process the fracture was virtually reduced. Based on the reduced fracture model, patient-specific titanium plates including polyamide drilling guides were designed, 3D printed and milled for intra-operative use. One of the advantages of this procedure is that the personalised plates could be tailored to both the shape of the pelvis and the type of fracture. The optimal screw directions and sizes were predetermined in the 3D model. The virtual plan was translated towards the surgical procedure by using the surgical guides and patient-specific osteosynthesis. Besides the description of the newly developed multi-disciplinary workflow, a clinical case example is presented to demonstrate that this technique is feasible and promising for the operative treatment of complex acetabular fractures. Copyright © 2017 Elsevier Ltd. All rights reserved.
Razek, Ahmed Abdel Khalek Abdel; Ezzat, Amany; Azmy, Emad; Tharwat, Nehal
2013-08-01
The authors evaluated the role of whole-body 64-slice multidetector computed tomography (WB-MDCT) in treatment planning for multiple myeloma. This was a prospective study of 28 consecutive patients with multiple myeloma (19 men, nine women; age range, 51-73 years; mean age, 60 years) who underwent WB-MDCT and conventional radiography (CR) of the skeleton. The images were interpreted for the presence of bony lesions, medullary lesions, fractures and extraosseous lesions. We evaluated any changes in treatment planning as a result of WB-MDCT findings. WB-MDCT was superior to CR for detecting bony lesions (p=0.001), especially of the spine (p=0.001) and thoracic cage (p=0.006). WB-MDCT upstaged 14 patients, with a significant difference in staging (p=0.002) between WB-MDCT and CR. Medullary involvement either focal (n=6) or diffuse (n=3) had a positive correlation with the overall score (r=0.790) and stage (r=0.618) of disease. Spine fractures were better detected at WB-MDCT (n=4) than at CR (n=2). Extraosseous soft tissue lesions (n=7) were detected only at WB-MDCT. Findings detected at the WB-MDCT led to changes in the patient's treatment plan in 39% of cases. Upstaging of seven patients (25%) altered the medical treatment plan, and four of 28 (14%) patients required additional radiotherapy (7%) and vertebroplasty (7%). We conclude that WB-MDCT has an impact on treatment planning and prognosis in patients with multiple myeloma, as it has high rate of detecting cortical and medullary bone lesions, spinal fracture and extraosseous lesions. This information may alter treatment planning in multiple myeloma due to disease upstaging and detection of spine fracture and extraosseous spinal lesions.
Basic principles of fracture treatment in children.
Ömeroğlu, Hakan
2018-04-01
This review aims to summarize the basic treatment principles of fractures according to their types and general management principles of special conditions including physeal fractures, multiple fractures, open fractures, and pathologic fractures in children. Definition of the fracture is needed for better understanding the injury mechanism, planning a proper treatment strategy, and estimating the prognosis. As the healing process is less complicated, remodeling capacity is higher and non-union is rare, the fractures in children are commonly treated by non-surgical methods. Surgical treatment is preferred in children with multiple injuries, in open fractures, in some pathologic fractures, in fractures with coexisting vascular injuries, in fractures which have a history of failed initial conservative treatment and in fractures in which the conservative treatment has no/little value such as femur neck fractures, some physeal fractures, displaced extension and flexion type humerus supracondylar fractures, displaced humerus lateral condyle fractures, femur, tibia and forearm shaft fractures in older children and adolescents and unstable pelvis and acetabulum fractures. Most of the fractures in children can successfully be treated by non-surgical methods.
Black, Emily Anne; Lawson, Christy M; Smith, Scott; Daley, Brian J
2011-01-01
Introduction Open fractures of the pelvis remain a devastating injury with a high mortality and morbidity. Such injuries require an aggressive treatment plan and the coordination of trauma and orthopaedic surgeons to achieve the best outcomes. We report our experience at the University of Tennessee Medical Center at Knoxville with open pelvic fractures over the last ten years. Methods After IRB and institutional approval, we reviewed patients admitted with a diagnosis of open fracture of the pelvis from 1999 to 2009. Demographic and admission data were recorded in the trauma registry (TRACS) of the Level I Trauma Center, serving the 1.2 million people living in the regions of east Tennessee, western North Carolina and southeastern Kentucky. Data on fractures were obtained from review of the medical records and radiographs within the chart Results There were 3053 pelvic fractures from January 1999 to December 2009. There were 231 deaths in this group (6%) and ages ranged from 18 to 89 years old and Injury Severity Scores ranged from 4 to 75, with a mean of 18.3. Seventy five percent of patients were able to be discharged home. Fifty-two fractures were open. There were 43 men and the mean age was 39 years old. Average ISS was 23 and ranged from 5 to 50. There were 10 deaths (19%) and eight patients underwent an-gioembolization for control of bleeding (3 deaths). Motorcycle crashes were the most frequent cause of an open fracture, with lateral compression injuries representing 71%. A defined algorithm for fracture management has been in place and employed to assure adequate resuscitation and fracture care and is presented. Discussion Open pelvic fractures are usually the result of a high energy transfer, and convey a high morbidity and mortality. A defined resuscitation and fixation strategy improves outcome from historical reports. Injuries from penetrating mechanisms are associated with less morbidity and lower mortality. PMID:22096441
Black, Emily Anne; Lawson, Christy M; Smith, Scott; Daley, Brian J
2011-01-01
Open fractures of the pelvis remain a devastating injury with a high mortality and morbidity. Such injuries require an aggressive treatment plan and the coordination of trauma and orthopaedic surgeons to achieve the best outcomes. We report our experience at the University of Tennessee Medical Center at Knoxville with open pelvic fractures over the last ten years. After IRB and institutional approval, we reviewed patients admitted with a diagnosis of open fracture of the pelvis from 1999 to 2009. Demographic and admission data were recorded in the trauma registry (TRACS) of the Level I Trauma Center, serving the 1.2 million people living in the regions of east Tennessee, western North Carolina and southeastern Kentucky. Data on fractures were obtained from review of the medical records and radiographs within the chart. There were 3053 pelvic fractures from January 1999 to December 2009. There were 231 deaths in this group (6%) and ages ranged from 18 to 89 years old and Injury Severity Scores ranged from 4 to 75, with a mean of 18.3. Seventy five percent of patients were able to be discharged home. Fifty-two fractures were open. There were 43 men and the mean age was 39 years old. Average ISS was 23 and ranged from 5 to 50. There were 10 deaths (19%) and eight patients underwent angioembolization for control of bleeding (3 deaths). Motorcycle crashes were the most frequent cause of an open fracture, with lateral compression injuries representing 71%. A defined algorithm for fracture management has been in place and employed to assure adequate resuscitation and fracture care and is presented. Open pelvic fractures are usually the result of a high energy transfer, and convey a high morbidity and mortality. A defined resuscitation and fixation strategy improves outcome from historical reports. Injuries from penetrating mechanisms are associated with less morbidity and lower mortality.
Planning acetabular fracture reduction using patient-specific multibody simulation of the hip
NASA Astrophysics Data System (ADS)
Oliveri, Hadrien; Boudissa, Mehdi; Tonetti, Jerome; Chabanas, Matthieu
2017-03-01
Acetabular fractures are a challenge in orthopedic surgery. Computer-aided solutions were proposed to segment bone fragments, simulate the fracture reduction or design the osteosynthesis fixation plates. This paper addresses the simulation part, which is usually carried out by freely moving bone fragments with six degrees of freedom to reproduce the pre-fracture state. Instead we propose a different paradigm, closer to actual surgeon's requirements: to simulate the surgical procedure itself rather than the desired result. A simple, patient-specific, biomechanical multibody model is proposed, integrating the main ligaments and muscles of the hip joint while accounting for contacts between bone fragments. Main surgical tools and actions can be simulated, such as clamps, Schanz screws or traction of the femur. Simulations are computed interactively, which enables clinicians to evaluate different strategies for an optimal surgical planning. Six retrospective cases were studied, with simple and complex fracture patterns. After interactively building the models from preoperative CT, gestures from the surgical reports were reproduced. Results of the simulations could then be compared with postoperative CT data. A qualitative study shows the model behavior is excellent and the simulated reductions fit the observed data. A more quantitative analysis is currently being completed. Two cases are particularly significant, for which the surgical reduction actually failed. Simulations show it was indeed not possible to reduce these fractures with the chosen approach. Had our simulator being used, a better planning may have avoided a second surgery to these patients.
LORENZ: a system for planning long-bone fracture reduction
NASA Astrophysics Data System (ADS)
Birkfellner, Wolfgang; Burgstaller, Wolfgang; Wirth, Joachim; Baumann, Bernard; Jacob, Augustinus L.; Bieri, Kurt; Traud, Stefan; Strub, Michael; Regazzoni, Pietro; Messmer, Peter
2003-05-01
Long bone fractures belong to the most common injuries encountered in clinical routine trauma surgery. Preoperative assessment and decision making is usually based on standard 2D radiographs of the injured limb. Taking into account that a 3D - imaging modality such as computed tomography (CT) is not used for diagnosis in clinical routine, we have designed LORENZ, a fracture reduction planning tool based on such standard radiographs. Taking into account the considerable success of so-called image free navigation systems for total knee replacement in orthopaedic surgery, we assume that a similar tool for long bone fracture reposition should have considerable impact on computer-aided trauma surgery in a standard clinical routine setup. The case for long bone fracture reduction is, however, somewhat more complicated since not only scale independent angles indicating biomechanical measures such as varus and valgus are involved. Reduction path planning requires that the individual anatomy and the classification of the fracture is taken into account. In this paper, we present the basic ideas of this planning tool, it's current state, and the methodology chosen. LORENZ takes one or more conventional radiographs of the broken limb as input data. In addition, one or more x-rays of the opposite healthy bone are taken and mirrored if necessary. A most adequate CT model is being selected from a database; currently, this is achieved by using a scale space approach on the digitized x-ray images and comparing standard perspective renderings to these x-rays. After finding a CT-volume with a similar bone, a triangulated surface model is generated, and the surgeon can break the bone and arrange the fragments in 3D according to the x-ray images of the broken bone. Common osteosynthesis plates and implants can be loaded from CAD-datasets and are visualized as well. In addition, LORENZ renders virtual x-ray views of the fracture reduction process. The hybrid surface/voxel rendering engine of LORENZ also features full collision detection of fragments and implants by using the RAPID collision detection library. The reduction path is saved, and a TCP/IP interface to a robot for executing the reduction was added. LORENZ is platform independent and was programmed using Qt, AVW and OpenGL. We present a prototype for computer-aided fracture reduction planning based on standard radiographs. First test on clinical CT-Xray image pairs showed good performance; a current effort focuses on improving the speed of model retrieval by using orthonormal image moment decomposition, and on clinical evaluation for both training and surgical planning purposes. Furthermore, user-interface aspects are currently under evaluation and will be discussed.
Treatment of Die-Punch Fractures with 3D Printing Technology.
Chen, Chunhui; Cai, Leyi; Zhang, Chuanxu; Wang, Jianshun; Guo, Xiaoshan; Zhou, Yifei
2017-07-19
We evaluated the feasibility, accuracy and effectiveness of applying three-dimensional (3D) printing technology for preoperative planning for die-punch fractures. A total of 107 patients who underwent die-punch fracture surgery were enrolled in the study. They were randomly divided into two groups: 52 cases in the 3D model group and 55 cases in the routine group. A 3D digital model of each die-punch fracture was reconstructed in the 3D group. The 3D digital model was imported to a 3D printer to build the full solid model. The operation time, blood loss volume, and the number of intraoperative fluoroscopy were recorded. Follow-up was performed to evaluate the patients' surgical outcomes. Treatment of die-punch fractures using the 3D printing approach reduced the number of intraoperative fluoroscopy, blood loss volume, and operation time, but did not improve wrist function compared to those in the routine group. The patients wanted the doctor to use the 3D model to introduce the condition and operative plan because it was easier for them to understand. The orthopedic surgeons thought that the 3D model was useful for communicating with their patients, but their satisfaction with the preoperative plan was much lower than the benefit of using the 3D model to communicate with their patients. 3D printing technology produced more accurate morphometric information for orthopedists to provide personalized surgical planning and communicate better with their patients. However, it is difficult to use widely in the department of orthopedics.
Tseng, Ming-Yueh; Liang, Jersey; Shyu, Yea-Ing L; Wu, Chi-Chuan; Cheng, Huey-Shinn; Chen, Ching-Yen; Yang, Shu-Fang
2016-03-03
Health-related quality of life (HRQoL) has been used to assess subjects' prognosis and recovery following hip fracture. However, evidence is mixed regarding the effectiveness of interventions to improve HRQoL of elders with hip fracture. The purposes of this study were to identify distinct HRQoL trajectories and to evaluate the effects of two care models on these trajectories over 12 months following hip-fracture surgery. For this secondary analysis, data came from a randomized controlled trial of subjects with hip fracture receiving three treatment care models: interdisciplinary care (n = 97), comprehensive care (n = 91), and usual care (n = 93). Interdisciplinary care consisted of geriatric consultation, discharge planning, and 4 months of in-home rehabilitation. Comprehensive care consisted of interdisciplinary care plus management of malnutrition and depressive symptoms, fall prevention, and 12 months of in-home rehabilitation. Usual care included only in-hospital rehabilitation and occasional discharge planning, without geriatric consultation and in-home rehabilitation. Mental and physical HRQoL were measured at 1, 3, 6, and 12 months after discharge by the physical component summary scale (PCS) and mental component summary scale (MCS), respectively, of the Medical Outcomes Study Short Form 36, Taiwan version. Latent class growth modeling was used to identify PCS and MCS trajectories and to evaluate how they were affected by the interdisciplinary and comprehensive care models. We identified three quadratic PCS trajectories: poor PCS (n = 103, 36.6 %), moderate PCS (n = 96, 34.2 %), and good PCS (n = 82, 29.2 %). In contrast, we found three linear MCS trajectories: poor MCS (n = 39, 13.9 %), moderate MCS (n = 84, 29.9 %), and good MCS (n = 158, 56.2 %). Subjects in the comprehensive care and interdisciplinary care groups were more likely to experience a good PCS trajectory (b = 0.99, odds ratio [OR] = 2.69, confidence interval [CI] = 7.24-1.00, p = 0.049, and b = 1.32, OR = 3.75, CI = 10.53-1.33, p = 0.012, respectively) than those who received usual care. However, neither care model improved MCS. The interdisciplinary and comprehensive care models improved recovery from hip fracture by increasing subjects' odds for following a trajectory of good physical functioning after hospitalization. ClinicalTrials.gov ( NCT01350557 ).
Micromechanical Aspects of Hydraulic Fracturing Processes
NASA Astrophysics Data System (ADS)
Galindo-torres, S. A.; Behraftar, S.; Scheuermann, A.; Li, L.; Williams, D.
2014-12-01
A micromechanical model is developed to simulate the hydraulic fracturing process. The model comprises two key components. Firstly, the solid matrix, assumed as a rock mass with pre-fabricated cracks, is represented by an array of bonded particles simulated by the Discrete Element Model (DEM)[1]. The interaction is ruled by the spheropolyhedra method, which was introduced by the authors previously and has been shown to realistically represent many of the features found in fracturing and communition processes. The second component is the fluid, which is modelled by the Lattice Boltzmann Method (LBM). It was recently coupled with the spheropolyhedra by the authors and validated. An advantage of this coupled LBM-DEM model is the control of many of the parameters of the fracturing fluid, such as its viscosity and the injection rate. To the best of the authors' knowledge this is the first application of such a coupled scheme for studying hydraulic fracturing[2]. In this first implementation, results are presented for a two-dimensional situation. Fig. 1 shows one snapshot of the LBM-DEM coupled simulation for the hydraulic fracturing where the elements with broken bonds can be identified and the fracture geometry quantified. The simulation involves a variation of the underground stress, particularly the difference between the two principal components of the stress tensor, to explore the effect on the fracture path. A second study focuses on the fluid viscosity to examine the effect of the time scales of different injection plans on the fracture geometry. The developed tool and the presented results have important implications for future studies of the hydraulic fracturing process and technology. references 1. Galindo-Torres, S.A., et al., Breaking processes in three-dimensional bonded granular materials with general shapes. Computer Physics Communications, 2012. 183(2): p. 266-277. 2. Galindo-Torres, S.A., A coupled Discrete Element Lattice Boltzmann Method for the simulation of fluid-solid interaction with particles of general shapes. Computer Methods in Applied Mechanics and Engineering, 2013. 265(0): p. 107-119.
Semi-interpenetrating polymer network's of polyimides: Fracture toughness
NASA Technical Reports Server (NTRS)
Hansen, Marion Glenn
1988-01-01
The objective was to improve the fracture toughness of the PMR-15 thermosetting polyimide by co-disolving LaRC-TPI, a thermoplastic polyimide. The co-solvation of a thermoplastic into a thermoset produces an interpenetration of the thermoplastic polymer into the thermoset polyimide network. A second research program was planned around the concept that to improve the fracture toughness of a thermoset polyimide polymer, the molecular weight between crosslink points would be an important macromolecular topological parameter in producing a fracture toughened semi-IPN polyimide.
Risk factors for distal radius fracture in postmenopausal women.
Xu, Wenting; Ni, Cheng; Yu, Ren; Gu, Guoqing; Wang, Zheren; Zheng, Guoqing
2017-05-01
The aim of this work was to explore the risk factors for distal radius fracture in postmenopausal women. A total of 611 postmenopausal women with distal radius fractures were included. In all, 173 patients with unstable distal radius fractures were included (unstable fracture group), while there were 438 patients with stable distal radius fractures (stable fracture group). The control group comprised 800 postmenopausal women with no fracture. A questionnaire survey was conducted. Compared with the control group, the 611 postmenopausal women with distal radius fractures had a higher body mass index (BMI). Advanced age and higher BMI were more common in the unstable fracture group than in the stable fracture group (P <0.05). A higher proportion of the 611 postmenopausal women with a distal radius fracture had fallen in the last 12 months than in the control group. Comorbidities and the frequency of falls in the last 12 months were higher in the unstable fracture group than in the stable fracture group (P < 0.05). A higher proportion of the control group was taking calcium supplements, while the proportion taking calcium supplementation in the unstable fracture group was lower than that in the stable fracture group (P < 0.05). Osteoporosis in the two fracture groups (P < 0.05) was significantly higher than in the control group and was the highest in the unstable fracture group (P < 0.05). In postmenopausal women, obesity, falls, unknown osteoporosis status, and osteoporosis are associated with high risk of distal radius fracture. If comorbidities and advanced age are also present, this group of persons may be at higher risk for unstable distal radius fractures.
Magaraggia, Jessica; Wei, Wei; Weiten, Markus; Kleinszig, Gerhard; Vetter, Sven; Franke, Jochen; John, Adrian; Egli, Adrian; Barth, Karl; Angelopoulou, Elli; Hornegger, Joachim
2017-01-01
During a standard fracture reduction and fixation procedure of the distal radius, only fluoroscopic images are available for planning of the screw placement and monitoring of the drill bit trajectory. Our prototype intra-operative framework integrates planning and drill guidance for a simplified and improved planning transfer. Guidance information is extracted using a video camera mounted onto a surgical drill. Real-time feedback of the drill bit position is provided using an augmented view of the planning X-rays. We evaluate the accuracy of the placed screws on plastic bones and on healthy and fractured forearm specimens. We also investigate the difference in accuracy between guided screw placement versus freehand. Moreover, the accuracy of the real-time position feedback of the drill bit is evaluated. A total of 166 screws were placed. On 37 plastic bones, our obtained accuracy was [Formula: see text] mm, [Formula: see text] and [Formula: see text] in tip position and orientation (azimuth and elevation), respectively. On the three healthy forearm specimens, our obtained accuracy was [Formula: see text] mm, [Formula: see text] and [Formula: see text]. On the two fractured specimens, we attained: [Formula: see text] mm, [Formula: see text] and [Formula: see text]. When screw plans were applied freehand (without our guidance system), the achieved accuracy was [Formula: see text] mm, [Formula: see text], while when they were transferred under guidance, we obtained [Formula: see text] mm, [Formula: see text]. Our results show that our framework is expected to increase the accuracy in screw positioning and to improve robustness w.r.t. freehand placement.
Alamri, Sultan H; Kennedy, Courtney C; Marr, Sharon; Lohfeld, Lynne; Skidmore, Carly J; Papaioannou, Alexandra
2015-08-01
Osteoporosis is a major global health problem, especially among long-term care (LTC) facilities. Despite the availability of effective clinical guidelines to prevent osteoporosis and bone fractures, few LTC homes actually adhere to these practical recommendations. The purpose of this study was to identify barriers to the implementation of evidence-based practices for osteoporosis and fracture prevention in LTC facilities and elicit practical strategies to address these barriers. We performed a qualitative analysis of action plans formulated by Professional Advisory Committee (PAC) teams at 12 LTC homes in the intervention arm of the Vitamin D and Osteoporosis Study (ViDOS) in Ontario, Canada. PAC teams were comprised of medical directors, administrators, directors of care, pharmacists, dietitians, and other staff. Thematic content analysis was performed to identify the key themes emerging from the action plans. LTC teams identified several barriers, including lack of educational information and resources prior to the ViDOS intervention, difficulty obtaining required patient information for fracture risk assessment, and inconsistent prescribing of vitamin D and calcium at the time of admission. The most frequently suggested recommendations was to establish and adhere to standard admission orders regarding vitamin D, calcium, and osteoporosis therapies, improve the use of electronic medical records for osteoporosis and fracture risk assessment, and require bone health as a topic at quarterly reviews and multidisciplinary conferences. This qualitative study identified several important barriers and practical recommendations for improving the implementation of osteoporosis and fracture prevention guidelines in LTC settings.
Sawada, Hideyoshi; Shinohara, Takaaki; Natsume, Tadahiro; Hirata, Hitoshi
2016-11-01
Ulnar styloid fractures are often associated with distal radius fractures. However, controversy exists regarding whether to treat ulnar styloid fractures. This study aimed to evaluate clinical effects of internal fixation for ulnar styloid fractures after distal radius fractures were treated with the volar locking plate system. We used prospectively collected data of distal radius fractures. 111 patients were enrolled in this study. A matched case-control study design was used. We selected patients who underwent fixation for ulnar styloid fractures (case group). Three control patients for each patient of the case group were matched on the basis of age, sex, and fracture type of distal radius fractures from among patients who did not undergo fixation for ulnar styloid fractures (control group). The case group included 16 patients (7 men, 9 women; mean age: 52.6 years; classification of ulnar styloid fractures: center, 3; base, 11; and proximal, 2). The control group included 48 patients (15 men, 33 women; mean age: 61.1 years; classification of ulnar styloid fractures: center, 10; base, 31; and proximal, 7). For radiographic examination, the volar tilt angle, radial inclination angle, and ulnar variance length were measured, and the union of ulnar styloid fractures was judged. For clinical examination, the range of motions, grip strength, Hand20 score, and Numeric Rating Scale score were evaluated. There was little correction loss for each radiological parameter of fracture reduction, and these parameters were not significantly different between the groups. The bone-healing rate of ulnar styloid fractures was significantly higher in the case group than in the control group, but the clinical results were not significantly different. We revealed that there was no need to fix ulnar styloid fractures when distal radius fractures were treated via open reduction and internal fixation with a volar locking plate system. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.
Integrated nutritional intervention in the elderly after hip fracture. A process evaluation.
Breedveld-Peters, José J L; Reijven, Petronella L M; Wyers, Caroline E; van Helden, Svenhjalmar; Arts, J J Chris; Meesters, Berry; Prins, Martin H; van der Weijden, Trudy; Dagnelie, Pieter C
2012-04-01
Within a multicentre randomized controlled trial aimed at improving the nutritional status and increase the speed of recovery of elderly hip fracture patients, we performed a process evaluation to investigate the feasibility of the intervention within the present Dutch health care system. Patients in the intervention group received nutritional counseling during 10 contacts. Oral nutritional supplements were advised as needed until three months after hip fracture surgery. The intervention was evaluated with respect to dieticians' adherence to the study protocol, content of nutritional counseling, and patients' adherence to recommendations given. We included 66 patients (mean age of 76, range 55-92 years); 74% women. Eighty-three percent of patients received all 10 contacts as planned, but in 62% of the patients one or more telephone calls had to be replaced by face to face contacts. Nutritional counseling was complete in 91% of contacts. Oral nutritional supplementation was needed for a median period of 76 days; 75% of the patients took the oral nutritional supplements as recommended. Nutritional counseling in elderly hip fracture patients through face to face contacts and telephone calls is feasible. However, individual tailoring of the intervention is recommended. The majority of hip fracture patients needed >2 months oral nutritional supplements to meet their nutritional requirements. The trial was registered at clincialtrails.gov as NCT00523575. Copyright © 2011 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
Nakada, Takafumi; Teranishi, Masaaki; Ueda, Yukio; Sone, Michihiko
2018-05-18
Patients with benign paroxysmal positional vertigo (BPPV) can have vitamin D deficiency, which is a cause of abnormal bone turnover. Several studies have established a relationship between osteoporosis and BPPV. The World Health Organization Fracture Risk Assessment Tool, widely known as FRAX ® (http://www.shef.ac.uk/FRAX), is a computer-based algorithm for assessing fracture risk. No direct comparison has been made between the FRAX scores of patients with BPPV and controls. The purpose of this study was to determine whether women with BPPV are at high risk of fracture as assessed using FRAX. The study involved 40 postmenopausal women diagnosed with BPPV between July 2015 and April 2016, and 40 postmenopausal women as controls. The 10-year major osteoporotic and hip fracture risks were calculated using FRAX and were compared between BPPV patients and controls using Welch's t test and a general linear model. The 10-year major osteoporotic fracture risk was 20.4%±12.1% for BPPV patients (aged 72.4±8.6years) and 14.3%±6.5% for controls (aged 71.2±6.3years). The 10-year hip fracture risk was 9.0%±9.8% for BPPV patients and 5.0%±3.9% for controls. The BPPV group had significantly higher 10-year major risks of osteoporotic fracture (p=0.0069) and hip fracture (p=0.0202) compared with controls. Similarly, after adjustment for age, the BPPV group had significantly higher 10-year risks of major osteoporotic fracture (p=0.0007) and hip fracture (p=0.0092) compared with controls. Fracture risk calculated using FRAX was significantly higher in the BPPV group than in controls. Women with BPPV may need early intervention to prevent future fractures. Copyright © 2018 Elsevier B.V. All rights reserved.
Operative Mortality After Arthroplasty for Femoral Neck Fracture and Hospital Volume.
Maceroli, Michael A; Nikkel, Lucas E; Mahmood, Bilal; Elfar, John C
2015-12-01
The purpose of the present study is to use a statewide, population-based data set to identify mortality rates at 30-day and 1-year postoperatively following total hip arthroplasty (THA) and hemiarthroplasty (HA) for displaced femoral neck fractures. The secondary aim of the study is to determine whether arthroplasty volume confers a protective effect on the mortality rate following femoral neck fracture treatment. New York's Statewide Planning and Research Cooperative System was used to identify 45 749 patients older than 60 years of age with a discharge diagnosis of femoral neck fracture undergoing THA or HA from 2000 through 2010. Comorbidities were identified using the Charlson comorbidity index. Mortality risk was modeled using Cox proportional hazards models while controlling for demographic and comorbid characteristics. High-volume THA centers were defined as those in the top quartile of arthroplasty volume, while low-volume centers were defined as the bottom quartile. Patients undergoing THA for femoral neck fracture rather than HA were younger (79 vs 83 years, P < .001), more likely to have rheumatoid disease, and less likely to have heart disease, dementia, cancer, or diabetes (all P < .05). Thirty-day mortality after HA was higher (8.4% vs 5.7%; P < .001) as was 1-year mortality (25.9% vs 17.8%; P < .001). After controlling for age, gender, ethnicity, and comorbidities, risk of mortality following THA was 21% lower (hazard ratio [HR] 0.79; P = .003) at 30 days and 22% lower (HR 0.78; P < .001) at 1 year than HA. Patients undergoing THA at high-volume arthroplasty centers had improved 1-year mortality when compared to those undergoing THA at low-volume hospitals (HR 0.55; P = .008). Based on this large, population-based study, there is no basis to assume THA carries a greater mortality risk after hip fracture than does standard HA, even when accounting for institutional volume of hip arthroplasty.
Intra-abdominal drain fracture following pancreatic necrosectomy.
Campbell, W; Wallace, W; Gibson, E; McCallion, K
2011-06-01
We describe a rare case of iatrogenic fracture of an intra-abdominal tube drain (Portex Robinson drain, Smiths Medical, Kent, UK) in a 74-year-old man. The fracture occurred at the level of an additionally placed fenestration and was identified on CT scanning prior to retrieval at planned re-laparotomy. This case highlights the potential dangers of modifying pre-formed drains and recommends against this practice.
Fracture characterization in a deep geothermal reservoir
NASA Astrophysics Data System (ADS)
Rühaak, Wolfram; Hehn, Vera; Hassanzadegan, Alireza; Tischner, Torsten
2017-04-01
At the geothermal research drilling Horstberg in North West Germany studies for the characterization of a vertical fracture are performed. The fracture was created by a massive hydraulic stimulation in 2003 in approx. 3700 m depth within rocks of the middle Buntsandstein. The fracture surface is in the order of 100,000 m2, depending on the flow rate at which water is injected. Besides hydraulic characterization, multiple tracer tests are planned. At the depth of interest the reservoir temperature is around 150 °C, pressure is around 600 bar (60 MPa) and due to salinity the water density is around 1200 kg/m3. Knowledge of tracer stability and behavior at these reservoir conditions is limited. Additionally, the planned tracer tests will be performed within one single borehole. In a closed cycle water is injected into the inner pipe of the well (tubing), which is separated by a permanent packer from the outer pipe (annulus). The water is produced back from the annulus approximately 150 m above the injection point. Thus, the circulation of thermal water between two sandstone layers via an artificial fracture can be achieved. Tests will be carried out with different flow rates and accordingly with different pressures, resulting in different fracture areas. Due to this test setup tracer signals will be stacked and will remain for a longer time in the fracture - which is the reason why different tracers are required. For an optimal characterization both conservative and reactive tracers will be used and different injection methods (continuous, instantaneous and pulsed) will be applied. For a proper setup of the tracer test numerical modelling studies are performed in advance. The relevant thermal, hydraulic and chemical processes (mainly adsorption and degredation) are coupled, resulting in a THC model; additionally the dependence of fracture aperture and area on fluid pressure has to be considered. Instead of applying a mechanically coupled model (THMC) a simplified approach is applied which takes the pressure dependence of the fracture permeability into account by using constitutive relations. Results of this modeling study will be presented together with details of the planned field study.
Liu, Xin; Zeng, Can-Jun; Lu, Jian-Sen; Lin, Xu-Chen; Huang, Hua-Jun; Tan, Xin-Yu; Cai, Dao-Zhang
2017-03-20
To evaluate the feasibility and effectiveness of using 3D printing and computer-assisted surgical simulation in preoperative planning for acetabular fractures. A retrospective analysis was performed in 53 patients with pelvic fracture, who underwent surgical treatment between September, 2013 and December, 2015 with complete follow-up data. Among them, 19 patients were treated with CT three-dimensional reconstruction, computer-assisted virtual reset internal fixation, 3D model printing, and personalized surgery simulation before surgery (3D group), and 34 patients underwent routine preoperative examination (conventional group). The intraoperative blood loss, transfusion volume, times of intraoperative X-ray, operation time, Matta score and Merle D' Aubigne & Postel score were recorded in the 2 groups. Preoperative planning and postoperative outcomes in the two groups were compared. All the operations were completed successfully. In 3D group, significantly less intraoperative blood loss, transfusion volume, fewer times of X-ray, and shortened operation time were recorded compared with those in the conventional group (P<0.05). According to the Matta scores, excellent or good fracture reduction was achieved in 94.7% (18/19) of the patients in 3D group and in 82.4% (28/34) of the patients in conventional group; the rates of excellent and good hip function at the final follow-up were 89.5% (17/19) in the 3D group and 85.3% (29/34) in the conventional group (P>0.05). In the 3D group, the actual internal fixation well matched the preoperative design. 3D printing and computer-assisted surgical simulation for preoperative planning is feasible and accurate for management of acetabular fracture and can effectively improve the operation efficiency.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gutierrez, Marte
The research project aims to develop and validate an advanced computer model that can be used in the planning and design of stimulation techniques to create engineered reservoirs for Enhanced Geothermal Systems. The specific objectives of the proposal are to: 1) Develop a true three-dimensional hydro-thermal fracturing simulator that is particularly suited for EGS reservoir creation. 2) Perform laboratory scale model tests of hydraulic fracturing and proppant flow/transport using a polyaxial loading device, and use the laboratory results to test and validate the 3D simulator. 3) Perform discrete element/particulate modeling of proppant transport in hydraulic fractures, and use the resultsmore » to improve understand of proppant flow and transport. 4) Test and validate the 3D hydro-thermal fracturing simulator against case histories of EGS energy production. 5) Develop a plan to commercialize the 3D fracturing and proppant flow/transport simulator. The project is expected to yield several specific results and benefits. Major technical products from the proposal include: 1) A true-3D hydro-thermal fracturing computer code that is particularly suited to EGS, 2) Documented results of scale model tests on hydro-thermal fracturing and fracture propping in an analogue crystalline rock, 3) Documented procedures and results of discrete element/particulate modeling of flow and transport of proppants for EGS applications, and 4) Database of monitoring data, with focus of Acoustic Emissions (AE) from lab scale modeling and field case histories of EGS reservoir creation.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gutierrez, Marte
2013-12-31
This research project aims to develop and validate an advanced computer model that can be used in the planning and design of stimulation techniques to create engineered reservoirs for Enhanced Geothermal Systems. The specific objectives of the proposal are to; Develop a true three-dimensional hydro-thermal fracturing simulator that is particularly suited for EGS reservoir creation; Perform laboratory scale model tests of hydraulic fracturing and proppant flow/transport using a polyaxial loading device, and use the laboratory results to test and validate the 3D simulator; Perform discrete element/particulate modeling of proppant transport in hydraulic fractures, and use the results to improve understandmore » of proppant flow and transport; Test and validate the 3D hydro-thermal fracturing simulator against case histories of EGS energy production; and Develop a plan to commercialize the 3D fracturing and proppant flow/transport simulator. The project is expected to yield several specific results and benefits. Major technical products from the proposal include; A true-3D hydro-thermal fracturing computer code that is particularly suited to EGS; Documented results of scale model tests on hydro-thermal fracturing and fracture propping in an analogue crystalline rock; Documented procedures and results of discrete element/particulate modeling of flow and transport of proppants for EGS applications; and Database of monitoring data, with focus of Acoustic Emissions (AE) from lab scale modeling and field case histories of EGS reservoir creation.« less
ERIC Educational Resources Information Center
Anila, Swarupa
2017-01-01
Inclusion strategies and approaches in interpretive planning processes for exhibitions are often resisted because they challenge precedents in museum practice. Maintaining traditional models may seem more comfortable for many museum professionals than to do the work of closely examining, fracturing, and transforming the practices that prioritize…
QAPP for Hydraulic Fracturing (HF) Surface Spills Data Analysis
This QAPP provides information concerning the analysis of spills associated with hydraulic fracturing. This project is relevant to both the chemical mixing and flowback and produced water stages of the HF water cycle as found in the HF Study Plan.
Vehmeijer, Maarten; van Eijnatten, Maureen; Liberton, Niels; Wolff, Jan
2016-08-01
Fractures of the orbital floor are often a result of traffic accidents or interpersonal violence. To date, numerous materials and methods have been used to reconstruct the orbital floor. However, simple and cost-effective 3-dimensional (3D) printing technologies for the treatment of orbital floor fractures are still sought. This study describes a simple, precise, cost-effective method of treating orbital fractures using 3D printing technologies in combination with autologous bone. Enophthalmos and diplopia developed in a 64-year-old female patient with an orbital floor fracture. A virtual 3D model of the fracture site was generated from computed tomography images of the patient. The fracture was virtually closed using spline interpolation. Furthermore, a virtual individualized mold of the defect site was created, which was manufactured using an inkjet printer. The tangible mold was subsequently used during surgery to sculpture an individualized autologous orbital floor implant. Virtual reconstruction of the orbital floor and the resulting mold enhanced the overall accuracy and efficiency of the surgical procedure. The sculptured autologous orbital floor implant showed an excellent fit in vivo. The combination of virtual planning and 3D printing offers an accurate and cost-effective treatment method for orbital floor fractures. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Cauley, Jane A.; LaCroix, Andrea Z.; Robbins, John A.; Larson, Joseph; Wallace, Robert; Wactawski-Wende, Jean; Chen, Zhao; Bauer, Douglas C.; Cummings, Steven R.; Jackson, Rebecca
2009-01-01
Purpose To test the hypothesis that the reduction in fractures with hormone therapy (HT) is greater in women with lower estradiol levels. Methods We conducted a nested case-control study within the Women’s Health Initiative HT Trials. The sample included 231 hip fracture case-control pairs and a random sample of 519 all fracture case-control pairs. Cases and controls were matched for age, ethnicity, randomization date, fracture history and hysterectomy status. Hormones were measured prior to randomization. Incident cases of fracture identified over an average follow-up of 6.53 years. Results There was no evidence that the effect of HT on fracture differed by baseline estradiol (E2) or sex hormone binding globulin (SHBG). Across all quartiles of E2 and SHBG, women randomized to HT had about a 50% lower risk of fracture including hip fracture, compared to placebo. Conclusion The effect of HT on fracture reduction is independent of estradiol and SHBG levels. PMID:19436934
Damage Tolerance of Composites
NASA Technical Reports Server (NTRS)
Hodge, Andy
2007-01-01
Fracture control requirements have been developed to address damage tolerance of composites for manned space flight hardware. The requirements provide the framework for critical and noncritical hardware assessment and testing. The need for damage threat assessments, impact damage protection plans, and nondestructive evaluation are also addressed. Hardware intended to be damage tolerant have extensive coupon, sub-element, and full-scale testing requirements in-line with the Building Block Approach concept from the MIL-HDBK-17, Department of Defense Composite Materials Handbook.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Potirniche, Gabriel; Barlow, Fred D.; Charit, Indrajit
2013-11-26
A recent workshop on next-generation nuclear plant (NGNP) topics underscored the need for research studies on the creep fracture behavior of two materials under consideration for reactor pressure vessel (RPV) applications: 9Cr-1Mo and SA-5XX steels. This research project will provide a fundamental understanding of creep fracture behavior of modified 9Cr-1Mo steel welds for through modeling and experimentation and will recommend a design for an RPV structural health monitoring system. Following are the specific objectives of this research project: Characterize metallurgical degradation in welded modified 9Cr-1Mo steel resulting from aging processes and creep service conditions; Perform creep tests and characterize themore » mechanisms of creep fracture process; Quantify how the microstructure degradation controls the creep strength of welded steel specimens; Perform finite element (FE) simulations using polycrystal plasticity to understand how grain texture affects the creep fracture properties of welds; Develop a microstructure-based creep fracture model to estimate RPVs service life; Manufacture small, prototypic, cylindrical pressure vessels, subject them to degradation by aging, and measure their leak rates; Simulate damage evolution in creep specimens by FE analyses; Develop a model that correlates gas leak rates from welded pressure vessels with the amount of microstructural damage; Perform large-scale FE simulations with a realistic microstructure to evaluate RPV performance at elevated temperatures and creep strength; Develop a fracture model for the structural integrity of RPVs subjected to creep loads; and Develop a plan for a non-destructive structural health monitoring technique and damage detection device for RPVs.« less
2014-01-01
Background Bone graft substitutes are widely used for reconstruction of posttraumatic bone defects. However, their clinical significance in comparison to autologous bone grafting, the gold-standard in reconstruction of larger bone defects, still remains under debate. This prospective, randomized, controlled clinical study investigates the differences in pain, quality of life, and cost of care in the treatment of tibia plateau fractures-associated bone defects using either autologous bone grafting or bioresorbable hydroxyapatite/calcium sulphate cement (CERAMENT™|BONE VOID FILLER (CBVF)). Methods/Design CERTiFy (CERament™ Treatment of Fracture defects) is a prospective, multicenter, controlled, randomized trial. We plan to enroll 136 patients with fresh traumatic depression fractures of the proximal tibia (types AO 41-B2 and AO 41-B3) in 13 participating centers in Germany. Patients will be randomized to receive either autologous iliac crest bone graft or CBVF after reduction and osteosynthesis of the fracture to reconstruct the subchondral bone defect and prevent the subsidence of the articular surface. The primary outcome is the SF-12 Physical Component Summary at week 26. The co-primary endpoint is the pain level 26 weeks after surgery measured by a visual analog scale. The SF-12 Mental Component Summary after 26 weeks and costs of care will serve as key secondary endpoints. The study is designed to show non-inferiority of the CBVF treatment to the autologous iliac crest bone graft with respect to the physical component of quality of life. The pain level at 26 weeks after surgery is expected to be lower in the CERAMENT bone void filler treatment group. Discussion CERTiFy is the first randomized multicenter clinical trial designed to compare quality of life, pain, and cost of care in the use of the CBVF and the autologous iliac crest bone graft in the treatment of tibia plateau fractures. The results are expected to influence future treatment recommendations. Trial registration number ClinicalTrials.gov: NCT01828905 PMID:24606670
Biomechanical concepts applicable to minimally invasive fracture repair in small animals.
Chao, Peini; Lewis, Daniel D; Kowaleski, Michael P; Pozzi, Antonio
2012-09-01
Understanding the basic biomechanical principles of surgical stabilization of fractures is essential for developing an appropriate preoperative plan as well as making prudent intraoperative decisions. This article aims to provide basic biomechanical knowledge essential to the understanding of the complex interaction between the mechanics and biology of fracture healing. The type of healing and the outcome can be influenced by several mechanical factors, which depend on the interaction between bone and implant. The surgeon should understand the mechanical principles of fracture fixation and be able to choose the best type of fixation for each specific fracture. Copyright © 2012 Elsevier Inc. All rights reserved.
Yang, Long; Shang, Xian-Wen; Fan, Jian-Nan; He, Zhi-Xu; Wang, Jian-Ji; Liu, Miao; Zhuang, Yong; Ye, Chuan
2016-01-01
To evaluate the effect of 3D printing in treating trimalleolar fractures and its roles in physician-patient communication, thirty patients with trimalleolar fractures were randomly divided into the 3D printing assisted-design operation group (Group A) and the no-3D printing assisted-design group (Group B). In Group A, 3D printing was used by the surgeons to produce a prototype of the actual fracture to guide the surgical treatment. All patients underwent open reduction and internal fixation. A questionnaire was designed for doctors and patients to verify the verisimilitude and effectiveness of the 3D-printed prototype. Meanwhile, the operation time and the intraoperative blood loss were compared between the two groups. The fracture prototypes were accurately printed, and the average overall score of the verisimilitude and effectiveness of the 3D-printed prototypes was relatively high. Both the operation time and the intraoperative blood loss in Group A were less than those in Group B (P < 0.05). Patient satisfaction using the 3D-printed prototype and the communication score were 9.3 ± 0.6 points. A 3D-printed prototype can faithfully reflect the anatomy of the fracture site; it can effectively help the doctors plan the operation and represent an effective tool for physician-patient communication.
The Contribution of SPECT/CT in the Diagnosis of Stress Fracture of the Proximal Tibia.
Okudan, Berna; Coşkun, Nazım; Arıcan, Pelin
2018-02-01
Stress fractures are injuries most commonly seen in the lower limbs and are usually caused by repetitive stress. While the distal and middle third of the tibia is the most frequent site for stress fractures (almost 50%), stress fractures of the proximal tibia is relatively rare and could be confused with other types of tibial fractures, thus altering management plans for the clinician. Early diagnosis of stress fractures is also important to avoid complications. Imaging plays an important role in the diagnosis of stress fractures, especially bone scan. Combined with single-photon emission computed tomography/computed tomography (SPECT/CT) it is an important imaging technique for stress fractures in both upper and lower extremities, and is widely preferred over other imaging techniques. In this case, we present the case of a 39-year-old male patient diagnosed with stress fracture of the proximal tibia and demonstrate the contribution of CT scan fused with SPECT imaging in the early diagnosis of stress fracture prior to other imaging modalities.
Hung, Chun-Chi; Li, Yuan-Ta; Chou, Yu-Ching; Chen, Jia-En; Wu, Chia-Chun; Shen, Hsain-Chung; Yeh, Tsu-Te
2018-05-03
Treating pelvic fractures remains a challenging task for orthopaedic surgeons. We aimed to evaluate the feasibility, accuracy, and effectiveness of three-dimensional (3D) printing technology and computer-assisted virtual surgery for pre-operative planning in anterior ring fractures of the pelvis. We hypothesized that using 3D printing models would reduce operation time and significantly improve the surgical outcomes of pelvic fracture repair. We retrospectively reviewed the records of 30 patients with pelvic fractures treated by anterior pelvic fixation with locking plates (14 patients, conventional locking plate fixation; 16 patients, pre-operative virtual simulation with 3D, printing-assisted, pre-contoured, locking plate fixation). We compared operative time, instrumentation time, blood loss, and post-surgical residual displacements, as evaluated on X-ray films, among groups. Statistical analyses evaluated significant differences between the groups for each of these variables. The patients treated with the virtual simulation and 3D printing-assisted technique had significantly shorter internal fixation times, shorter surgery duration, and less blood loss (- 57 minutes, - 70 minutes, and - 274 ml, respectively; P < 0.05) than patients in the conventional surgery group. However, the post-operative radiological result was similar between groups (P > 0.05). The complication rate was less in the 3D printing group (1/16 patients) than in the conventional surgery group (3/14 patients). The 3D simulation and printing technique is an effective and reliable method for treating anterior pelvic ring fractures. With precise pre-operative planning and accurate execution of the procedures, this time-saving approach can provide a more personalized treatment plan, allowing for a safer orthopaedic surgery.
[Treatment strategy and planning for pilon fractures].
Mittlmeier, Thomas; Wichelhaus, Alice
2017-08-01
Pilon fractures are mainly severe and prognostically serious injuries with a high rate of relevant soft tissue involvement. The adequate decision making and choice of treatment in the early phase of trauma are of paramount importance for the final outcome. This essentially encompasses the management of the soft tissue damage, the surgical planning and the differentiated selection of procedures. Most concepts of staged treatment nowadays offer a wide range of options which are integrated into expert-based algorithms. The aim of the present analysis was to display the strategy variations for the treatment of pilon fractures taking into account the advantages and disadvantages of the corresponding treatment concepts. A staged procedure including primary closed reduction employing ligamentotaxis and fixation of the joints of the hindfoot via tibiocalcaneal metatarsal fixation offers a safe basis for consecutive imaging and the selection of specific approaches for definitive reconstruction. A simultaneous reconstruction and fixation of the fibula during the primary intervention are generally not recommended in order to avoid any limitations for subsequent reconstructive procedures. A time frame for definitive reconstruction covers a period of up to 3 weeks after trauma and allows a detailed planning considering the individual dynamics of the soft tissue situation and any logistic requirements. For the choice of the definitive treatment concept a wide range of procedures and implants are available. There are also valid concepts for primary treatment of defined fracture constellations while primary arthrodesis represents a solution in cases of major destruction of the joint surface. Knowledge of the multiple procedural variations for pilon fracture treatment creates the basis to optimize the treatment modalities and to take into account individual parameters of the fracture.
Ren, Jiayin; He, Mingyun; Huang, Yongqing; Tian, WeiDong; Tang, Wei
2018-01-01
Objectives The treatment of condylar fractures has long been controversial. In this paper, we established a database for accurate measurement, storage, management and analysis of patients’ data, in order to help determine the best treatment plan. Methods First of all, the diagnosis and treatment database was established based on XNAT, including 339 cases of condylar fractures and their related information. Then image segmentation, registration and three-dimensional (3D) measurement were used to measure and analyze the condyle shapes. Statistical analysis was used to analyze the anatomical structure changes of condyle and the surrounding tissues at different stages before and after treatment. The processes of condylar fracture reestablishment at different stages were also dynamically monitored. Finally, based on all these information, the digital diagnosis and treatment plans for condylar fractures were developed. Results For the patients less than 18 years old with no significant dislocation, surgical treatment and conservative treatment were equally effective for intracapsular fracture, and had no significant difference for neck and basal fractures. For patients above 18 years old, there was no significant difference between the two treatment methods for intracapsular fractures; but for condylar neck and basal fractures, surgical treatment was better than conservative treatment. When condylar fracture shift angle was greater than 11 degrees, and mandibular ramus height reduction was greater than 4mm, the patients felt the strongest pain, and their mouths opening was severely restricted. There were 170 surgical cases with condylar fracture shift angel greater than 11 degrees, and 118 of them (69.4%) had good prognosis, 52 of them (30.6%) had complications such as limited mouth opening. There were 173 surgical cases with mandibular ramus height reduction more than 4mm, and 112 of them (64.7%) had good prognosis, 61 of them (35.3%) had complications such as limited mouth opening. Conclusions The establishment of XNAT condylar fracture database is helpful for establishing a digital diagnosis and treatment workflow for mandibular condylar fractures, providing new theoretical foundation and application basis for diagnosis and treatment of condylar fractures. PMID:29432477
Sharma, Naveen; Mandloi, Avinash; Agrawal, Ashish; Singh, Shailendra
2016-01-01
The clavicle, humerus and acromioclavicular (AC) joint separately are very commonly involved in traumatic injuries around the shoulder. Acromioclavicular joint dislocation with distal clavicle fracture is a well recognized entity in clinical practice. AC joint dislocation with mid shaft clavicle fracture is uncommon and only few cases have been reported in literature. However, to the best of our knowledge, this is the first case report to describe an acromioclavicular dislocation with ipsilateral mid shaft clavicle, mid shaft humerus and coracoid process fracture. Fractures of the humerus and clavicle along with the acromioclavicular joint dislocation were fixed at the same setting. A 65-year-old male met with a high velocity road traffic accident. Plain radiographs showed displaced mid third clavicle fracture with acromioclavicular joint dislocation with mid shaft humerus fracture. Surgical fixation was planned for humerus with interlocking nail, clavicle with locking plate and acromioclavicular joint with reconstruction of coracoclavicular ligaments. Intraoperatively, coracoid process was found to have a comminuted fracture. The operative plan had to be changed on table as coracoclavicular fixation was not possible. So acromioclavicular joint fixation was done using tension band wiring and the coracoclavicular ligament was repaired using a 2-0 ethibond. The comminuted coracoid fracture was managed conservatively. K wires were removed at 6 weeks. Early mobilization was started. In acromioclavicular joint injuries, clavicle must be evaluated for any injury. Although it is more commonly associated with distal clavicle fractures, it can be associated with middle third clavicle fractures. As plain radiographs, AP view are most of the times insufficient for viewing integrity of coracoid process, either special views like Stryker notch or CT scan may help in diagnosing such concealed injuries. When associated with fractures of the humerus and clavicle, anatomical restoration of acromioclavicular joint along with anatomical reduction and a rigid fixation of associated fractures is essential. Proper rehabilitation protocol is a must for achieving promising results. In our case, we were able to achieve a stable surgical fixation of both the fractures as well as AC joint, which enabled us to start early joint mobilization and rehabilitation.
Fractures of the Talus: State of the Art.
Vallier, Heather A
2015-09-01
Talus fractures occur rarely but are often associated with complications and functional limitations. Urgent reduction of associated dislocations is recommended with open reduction and internal fixation of displaced fractures when adjacent soft tissue injury permits. Delayed definitive fixation may reduce the risks of wound complications and infections. Restoration of articular and axial alignment is necessary to optimize ankle and hindfoot function. Despite this, posttraumatic arthrosis occurs frequently after talar neck and body fractures, especially with comminution of the talar body. Osteonecrosis is reported in up to half of talar neck fractures, although many of these injuries will revascularize without collapse of the talar dome. Initial fracture displacement and presence of open fractures increase the risk of osteonecrosis. Talar process fractures may be subtle and easily missed on plain radiographs. Advanced imaging will provide detail to facilitate treatment planning. Therapeutic Level V. See Instructions for Authors for a complete description of levels of evidence.
Chronic Pancreatitis and Fracture: A Retrospective, Population-Based Veterans Administration Study.
Munigala, Satish; Agarwal, Banke; Gelrud, Andres; Conwell, Darwin L
2016-03-01
There is increasing evidence that chronic pancreatitis (CP) is a risk factor for osteoporotic fracture, but data on males with CP and fracture prevalence are sparse. We determined the association of sex and age using a large Veterans Administration database. This was a retrospective analysis (1998-2007). Patients with CP (International Classification of Diseases code 577.1) and control subjects (without CP) were identified after exclusions and fracture prevalence (vertebral, hip, and wrist) were recorded. 453,912 Veterans Administration patients were identified (control subjects: 450,655 and patients with CP: 3257). Mean ages of control subjects and CP were 53.6 and 54.2 years (P < 0.014). Patients with CP had higher odds ratios of total fractures (2.35; 95% confidence interval [CI], 2.00-2.77), vertebral fracture 2.11 (95% CI, 1.44-3.01), hip fracture 3.49 (95% CI, 2.78-4.38), and wrist fracture 1.68 (95% CI, 1.29-2.18) when compared with control subjects. After adjusting for age group and etiology, patients with CP had increased odds of total fractures, vertebral fractures, and hip fractures (P < 0.05). In this male-predominate Veterans Administration study, patients with CP were at increased risk of osteoporotic fractures. The risk was higher for hip fracture (>3 times) in patients with CP compared with control subjects. All patients with CP older than 45 years, irrespective of sex, should be screened for bone mineral density loss.
2010-01-01
Background Vitamin D supplementation for fracture prevention is widespread despite conflicting interpretation of relevant randomised controlled trial (RCT) evidence. This study summarises quantitatively the current evidence from RCTs and observational studies regarding vitamin D, parathyroid hormone (PTH) and hip fracture risk. Methods We undertook separate meta-analyses of RCTs examining vitamin D supplementation and hip fracture, and observational studies of serum vitamin D status (25-hydroxyvitamin D (25(OH)D) level), PTH and hip fracture. Results from RCTs were combined using the reported hazard ratios/relative risks (RR). Results from case-control studies were combined using the ratio of 25(OH)D and PTH measurements of hip fracture cases compared with controls. Original published studies of vitamin D, PTH and hip fracture were identified through PubMed and Web of Science databases, searches of reference lists and forward citations of key papers. Results The seven eligible RCTs identified showed no significant difference in hip fracture risk in those randomised to cholecalciferol or ergocalciferol supplementation versus placebo/control (RR = 1.13[95%CI 0.98-1.29]; 801 cases), with no significant difference between trials of <800 IU/day and ≥800 IU/day. The 17 identified case-control studies found 33% lower serum 25(OH)D levels in cases compared to controls, based on 1903 cases. This difference was significantly greater in studies with population-based compared to hospital-based controls (χ21 (heterogeneity) = 51.02, p < 0.001) and significant heterogeneity was present overall (χ216 (heterogeneity) = 137.9, p < 0.001). Serum PTH levels in hip fracture cases did not differ significantly from controls, based on ten case-control studies with 905 cases (χ29 (heterogeneity) = 149.68, p < 0.001). Conclusions Neither higher nor lower dose vitamin D supplementation prevented hip fracture. Randomised and observational data on vitamin D and hip fracture appear to differ. The reason for this is unclear; one possible explanation is uncontrolled confounding in observational studies. Post-fracture PTH levels are unrelated to hip fracture risk. PMID:20540727
Navarro, Ronald A; Greene, Denise F; Burchette, Raoul; Funahashi, Tadashi; Dell, Richard
2011-07-01
Ethnic disparities in care have been documented with a number of musculoskeletal disorders including osteoporosis. We suggest a systems approach for ensuring osteoporosis care can minimize potential ethnic disparities in care. We evaluated variations in osteoporosis treatment by age, sex, and race/ethnicity by (1) measuring the rates of patients after a fragility fracture who had been evaluated by dual-energy xray absorptiometry and/or in whom antiosteoporosis treatment had been initiated and (2) determining the rates of osteoporosis treatment in patients who subsequently had a hip fracture. We implemented an integrated osteoporosis prevention program in a large health plan. Continuous screening of electronic medical records identified patients who met the criteria for screening for osteoporosis, were diagnosed with osteoporosis, or sustained a fragility fracture. At-risk patients were referred to care managers and providers to complete practice guidelines to close care gaps. Race/ethnicity was self-reported. Treatment rates after fragility fracture or osteoporosis treatment failures with later hip fracture were calculated. Data for the years 2008 to 2009 were stratified by age, sex, and race/ethnicity. Women (92.1%) were treated more often than men (75.2%) after index fragility fracture. The treatment rate after fragility fracture was similar among race/ethnic groups in either sex (women 87.4%-93.4% and men 69.3%-76.7%). Osteoporotic treatment before hip fracture was more likely in white men and women and Hispanic men than other race/ethnic and gender groups. Racial variation in osteoporosis care after fragility fracture in race/ethnic groups in this healthcare system was low when using the electronic medical record identifying care gaps, with continued reminders to osteoporosis disease management care managers and providers until those care gaps were closed.
Zhang, Bin-Fei; Zhang, Hong; Wang, Peng-Fei; Wang, Hu; Lei, Jin-Lai; Fu, Ya-Hui; Cong, Yu-Xuan; Huang, Hai; Huo, Xiao-Ming; Zhuang, Yan; Zhang, Kun
2017-09-01
Determining whether a Tile-B2 pelvic fracture is stable is very challenging. We sought to identify the role of ultrasonography in determining the stability of Tile-B2 pelvic fractures. We collected the clinical data of patients with Tile-B2 pelvic fractures who presented at Xi'an Hong-Hui Hospital between June 1, 2016, and August 5, 2016. The treatment strategy of each patient was determined by a team of senior surgeons in the department. A single sinologist observed the movement of the fracture sites in patients during rest, under compression, and during separation to determine fracture stability. According to the pelvic fracture stability assessment, an appropriate treatment strategy was redetermined. Overall, 7 patients, including 5 women and 2 men, with Tile-B2 pelvic fractures were included in this case series. During the initial examination, senior surgeons recommended that 2 patients should undergo internal fixation and 4 patients, conservative treatment; treatment was undecided for 1 patient. After ultrasonography examination, 4 patients underwent surgery via the Stoppa (n = 2) or ilioinguinal approach (n = 1) or cannulated screw fixation (n = 1). The rest of the patients (n = 3) received conventional treatment. Follow-up ranged from 6 to 10 months. Most of the patients showed excellent functions based on their last Majeed grading scores. There were no complications during the follow-up. Using ultrasonography examination, the preoperative treatment plan in 1 patient was changed, and the uncertain preoperative plan in 1 patient was identified. Preoperative assessment of stability using ultrasonography may assist surgeons in making appropriate treatment choices for patients with Tile-B2 pelvic fractures.
Hall, S E; Criddle, R A; Comito, T L; Prince, R L
1999-01-01
There have been several studies of the impact of vertebral osteoporotic fracture on the quality of life and functionality of individual subjects. To date, however, no direct comparisons with age-matched normal subjects without vertebral fracture have been made. The radiographs of 145 female clinic patients with vertebral fractures were reviewed by the study physicians. The controls were recruited from the electoral role and by media appeal. One hundred and sixty-seven women had radiographs taken to determine those without vertebral fracture. Fracture subjects and controls had to be ambulant and were excluded if they had significant radiologic evidence of degenerative disk or joint disease of the spine. One hundred cases and one hundred controls were matched by 5-year age groups. The number, position and severity of the vertebral fracture on the lateral radiographs of the cases was recorded. Quality of life was measured using the Short Form-36 (SF-36) (maximum score 100) and a utility score calculated from these results (maximum score 1). Two measurements of functionality were employed: the Modified Barthel Index (MBI) to assess the activities of daily living (maximum score 100) and the Timed 'Up & Go' (TUG) that measured the time taken for the subject to rise from sitting in a chair, walk 3 m along a line, return to the chair and sit down. The fracture subjects had 2.9 +/- 1.6 (mean +/- SD) vertebral fractures and the time since last fracture was 5.1 +/- 4.8 years. The SF-36 physical function component summary index results were: fracture subjects 36 +/- 11, controls 48 +/- 9 (p < 0.001). The SF-36 mental health component summary index results were: fracture subjects 50 +/- 11, controls 54 +/- 8 (p < 0.05). The utility scores were: fracture subjects 0.64 +/- 0.08, controls 0.72 +/- 0.07 (p < 0.001). The MBI results were: fracture subjects 97 +/- 5, controls 99 +/- 1 (p < 0.01). The TUG results were: fracture subjects 13.8 +/- 7.3 s, controls 10.1 +/- 4.1 s (p < 0.01). TUG and MBI scores correlated well with SF-36 scores; however, no domain of the SF-36 or functional measure correlated with either the number of vertebral fractures or the time since last vertebral fracture. Thus, clinically reported vertebral fractures impair both the quality of life and functionality of these subjects. The adverse impact of vertebral fracture on quality of life and functionality needs to be recognized by medical practitioners, subjects and the community, so that adequate health resources can be devoted to the prevention and treatment of this debilitating condition condition.
NASA Astrophysics Data System (ADS)
Zhang, Chen; Zhu, Deyu; Luo, Qun; Liu, Luofu; Liu, Dongdong; Yan, Lin; Zhang, Yunzhao
2017-09-01
Natural fractures in seven wells from the Middle Permian Lucaogou Formation in the Junggar Basin were evaluated in light of regional structural evolution, tight reservoir geochemistry (including TOC and mineral composition), carbon and oxygen isotopes of calcite-filled fractures, and acoustic emission (AE). Factors controlling the development of natural fractures were analyzed using qualitative and/or semi-quantitative techniques, with results showing that tectonic factors are the primary control on fracture development in the Middle Permian Lucaogou Formation of the Junggar Basin. Analyses of calcite, dolomite, and TOC show positive correlations with the number of fractures, while deltaic lithofacies appear to be the most favorable for fracture development. Mineral content was found to be a major control on tectonic fracture development, while TOC content and sedimentary facies mainly control bedding fractures. Carbon and oxygen isotopes vary greatly in calcite-filled fractures (δ13C ranges from 0.87‰ to 7.98‰, while δ18O ranges from -12.63‰ to -5.65‰), indicating that fracture development increases with intensified tectonic activity or enhanced diagenetic alteration. By analyzing the cross-cutting relationships of fractures in core, as well as four Kaiser Effect points in the acoustic emission curve, we observed four stages of tectonic fracture development. First-stage fractures are extensional, and were generated in the late Triassic, with calcite fracture fills formed between 36.51 °C and 56.89 °C. Second-stage fractures are shear fractures caused by extrusion stress from the southwest to the northeast, generated by the rapid uplift of the Tianshan in the Middle and Late Jurassic; calcite fracture fills formed between 62.91 °C and 69.88 °C. Third-stage fractures are NNW-trending shear fractures that resulted from north-south extrusion and thrusting in a foreland depression along the front of the Early Cretaceous Bogda Mountains. Calcite fracture fills formed between 81.74 °C and 85.43 °C. Fourth-stage fractures inherited the tectonic framework of the third stage, resulting in fractures with the same orientation, but without calcite filling. By differentiating the various stages of fracture development, we were able to better understand the origin of fractures in tight oil reservoirs and their significance for exploration and development.
3D reconstruction of highly fragmented bone fractures
NASA Astrophysics Data System (ADS)
Willis, Andrew; Anderson, Donald; Thomas, Thad; Brown, Thomas; Marsh, J. Lawrence
2007-03-01
A system for the semi-automatic reconstruction of highly fragmented bone fractures, developed to aid in treatment planning, is presented. The system aligns bone fragment surfaces derived from segmentation of volumetric CT scan data. Each fragment surface is partitioned into intact- and fracture-surfaces, corresponding more or less to cortical and cancellous bone, respectively. A user then interactively selects fracture-surface patches in pairs that coarsely correspond. A final optimization step is performed automatically to solve the N-body rigid alignment problem. The work represents the first example of a 3D bone fracture reconstruction system and addresses two new problems unique to the reconstruction of fractured bones: (1) non-stationary noise inherent in surfaces generated from a difficult segmentation problem and (2) the possibility that a single fracture surface on a fragment may correspond to many other fragments.
Prescribing by general practitioners after an osteoporotic fracture.
Torgerson, D J; Dolan, P
1998-06-01
Osteoporosis is a major cause of morbidity and cost. Patients sustaining one osteoporotic fracture are at increased risk of having another fracture. The objective of this study was to examine the use of "bone drugs" for the prevention of further osteoporotic fractures among patients who have had a "typical" osteoporotic fracture. This study took a random sample of 300 women aged 50 and over who had sustained either a vertebral, hip or Colles fracture in 1995 from the General Practice Research Database (GPRD) and compared their use of bone drugs with 300 age and practice matched controls. Compared with age and practice matched control patients only vertebral fracture patients showed a statistically significant increase in the use of bone drugs in the year after fracture (39% and 2% for cases and controls respectively; 95% CI of difference 27% to 47%). Etidronate was the most commonly used compound. The majority of patients sustaining an osteoporotic fracture are not prescribed any pharmaceutical agents for the secondary prevention of fracture one year after a primary fracture.
Field Evaluation of Fracture Control in Tunnel Blasting
DOT National Transportation Integrated Search
1979-12-01
The objective of this research was to implement fracture control procedures in a tunnel project and to assess the practicality, advantages, disadvantages, performance and cost effectiveness of fracture control methods against smooth blasting procedur...
Mechanical stratigraphic controls on natural fracture spacing and penetration
NASA Astrophysics Data System (ADS)
McGinnis, Ronald N.; Ferrill, David A.; Morris, Alan P.; Smart, Kevin J.; Lehrmann, Daniel
2017-02-01
Fine-grained low permeability sedimentary rocks, such as shale and mudrock, have drawn attention as unconventional hydrocarbon reservoirs. Fracturing - both natural and induced - is extremely important for increasing permeability in otherwise low-permeability rock. We analyze natural extension fracture networks within a complete measured outcrop section of the Ernst Member of the Boquillas Formation in Big Bend National Park, west Texas. Results of bed-center, dip-parallel scanline surveys demonstrate nearly identical fracture strikes and slight variation in dip between mudrock, chalk, and limestone beds. Fracture spacing tends to increase proportional to bed thickness in limestone and chalk beds; however, dramatic differences in fracture spacing are observed in mudrock. A direct relationship is observed between fracture spacing/thickness ratio and rock competence. Vertical fracture penetrations measured from the middle of chalk and limestone beds generally extend to and often beyond bed boundaries into the vertically adjacent mudrock beds. In contrast, fractures in the mudrock beds rarely penetrate beyond the bed boundaries into the adjacent carbonate beds. Consequently, natural bed-perpendicular fracture connectivity through the mechanically layered sequence generally is poor. Fracture connectivity strongly influences permeability architecture, and fracture prediction should consider thin bed-scale control on fracture heights and the strong lithologic control on fracture spacing.
Incorporating Scale-Dependent Fracture Stiffness for Improved Reservoir Performance Prediction
NASA Astrophysics Data System (ADS)
Crawford, B. R.; Tsenn, M. C.; Homburg, J. M.; Stehle, R. C.; Freysteinson, J. A.; Reese, W. C.
2017-12-01
We present a novel technique for predicting dynamic fracture network response to production-driven changes in effective stress, with the potential for optimizing depletion planning and improving recovery prediction in stress-sensitive naturally fractured reservoirs. A key component of the method involves laboratory geomechanics testing of single fractures in order to develop a unique scaling relationship between fracture normal stiffness and initial mechanical aperture. Details of the workflow are as follows: tensile, opening mode fractures are created in a variety of low matrix permeability rocks with initial, unstressed apertures in the micrometer to millimeter range, as determined from image analyses of X-ray CT scans; subsequent hydrostatic compression of these fractured samples with synchronous radial strain and flow measurement indicates that both mechanical and hydraulic aperture reduction varies linearly with the natural logarithm of effective normal stress; these stress-sensitive single-fracture laboratory observations are then upscaled to networks with fracture populations displaying frequency-length and length-aperture scaling laws commonly exhibited by natural fracture arrays; functional relationships between reservoir pressure reduction and fracture network porosity, compressibility and directional permeabilities as generated by such discrete fracture network modeling are then exported to the reservoir simulator for improved naturally fractured reservoir performance prediction.
Orbital fractures due to domestic violence: an epidemiologic study.
Goldberg, Stuart H.; McRill, Connie M.; Bruno, Christopher R.; Ten Have, Tom; Lehman, Erik
2000-09-01
Domestic violence is an important cause of orbital fractures in women. Physicians who treat patients with orbital fractures may not suspect this mechanism of injury. The purpose of this study was to assess the association between domestic violence and orbital fractures. A medical center-based case-control study with matching on age and site of admission was done. Medical center databases were searched using ICD-9 codes to identify all cases of orbital fractures encountered during a three-year period. Medical records of female patients age 13 and older were reviewed along with those of age, gender and site of admission matched controls. A stratified exact test was employed to test the association between domestic violence and orbital fracture. Among 41 adult female cases with orbital fractures treated at our medical center, three (7.3%) reported domestic violence compared to zero among the matched controls (p = 0.037). We believe that domestic violence may be under-reported in both orbital fracture cases and controls. This may result in an underestimate of the orbital fracture versus domestic violence association. Domestic violence is a serious women's health and societal problem. Domestic violence may have a variety of presentations, including illnesses and injuries. Orbital fracture is an identifiable manifestation of domestic violence. Domestic violence is more likely to be detected in adult female hospital patients with orbital fracture than in matched controls with any other diagnosis. Physicians who treat patients with orbital fractures should be familiar with this mechanism of injury.
Comparison of circummandibular wiring with resorbable bone plates in pediatric mandibular fractures.
Saikrishna, D; Gupta, Nimish
2010-06-01
Pediatric patients present a unique challenge to maxillofacial surgeons in terms of their treatment planning as well as in their functional and nutritional needs which are different from that of adult patients. Early literature has advocated conservative closed management of pediatric fractures to prevent complications. However recent advances in maxillofacial surgery has enabled us to use biodegradable plates and screws, which overcomes the limitations of metallic plates. We present a comparison of two cases of parasymphysis fracture treated with circum-mandibular wiring and biodegradable plate fixation their outcome in terms of fracture healing and functional stability.
NASA Astrophysics Data System (ADS)
Massiot, Cécile; Nicol, Andrew; McNamara, David D.; Townend, John
2017-08-01
Analysis of fracture orientation, spacing, and thickness from acoustic borehole televiewer (BHTV) logs and cores in the andesite-hosted Rotokawa geothermal reservoir (New Zealand) highlights potential controls on the geometry of the fracture system. Cluster analysis of fracture orientations indicates four fracture sets. Probability distributions of fracture spacing and thickness measured on BHTV logs are estimated for each fracture set, using maximum likelihood estimations applied to truncated size distributions to account for sampling bias. Fracture spacing is dominantly lognormal, though two subordinate fracture sets have a power law spacing. This difference in spacing distributions may reflect the influence of the andesitic sequence stratification (lognormal) and tectonic faults (power law). Fracture thicknesses of 9-30 mm observed in BHTV logs, and 1-3 mm in cores, are interpreted to follow a power law. Fractures in thin sections (˜5 μm thick) do not fit this power law distribution, which, together with their orientation, reflect a change of controls on fracture thickness from uniform (such as thermal) controls at thin section scale to anisotropic (tectonic) at core and BHTV scales of observation. However, the ˜5% volumetric percentage of fractures within the rock at all three scales suggests a self-similar behavior in 3-D. Power law thickness distributions potentially associated with power law fluid flow rates, and increased connectivity where fracture sets intersect, may cause the large permeability variations that occur at hundred meter scales in the reservoir. The described fracture geometries can be incorporated into fracture and flow models to explore the roles of fracture connectivity, stress, and mineral precipitation/dissolution on permeability in such andesite-hosted geothermal systems.
Report #15-P-0204, July 16, 2015. Enhanced EPA oversight of the permitting process for diesel fuel use during hydraulic fracturing can further EPA efforts to protect water resources, and establishment of a plan for determining whether to propose a chemical
Intermediate-Scale Hydraulic Fracturing in a Deep Mine - kISMET Project Summary 2016
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oldenburg, C. M.; Dobson, P. F.; Wu, Y.
In support of the U.S. DOE SubTER Crosscut initiative, we established a field test facility in a deep mine and designed and carried out in situ hydraulic fracturing experiments in the crystalline rock at the site to characterize the stress field, understand the effects of rock fabric on fracturing, and gain experience in monitoring using geophysical methods. The project also included pre- and post-fracturing simulation and analysis, laboratory measurements and experiments, and we conducted an extended analysis of the local stress state using previously collected data. Some of these activities are still ongoing. The kISMET (permeability (k) and Induced Seismicitymore » Management for Energy Technologies) experiments meet objectives in SubTER’s “stress” pillar and the “new subsurface signals” pillar. The kISMET site was established in the West Access Drift of SURF 4850 ft (1478 m) below ground (on the 4850L) in phyllite of the Precambrian Poorman Formation. We drilled and cored five near-vertical boreholes in a line on 3 m spacing, deviating the two outermost boreholes slightly to create a five-spot pattern around the test borehole centered in the test volume at ~1528 m (5013 ft). Laboratory measurements of core from the center test borehole showed P-wave velocity heterogeneity along each core indicating strong, fine-scale (~1 cm or smaller) changes in the mechanical properties of the rock. The load-displacement record on the core suggests that the elastic stiffness is anisotropic. Tensile strength ranges between 3-7.5 MPa and 5-12 MPa. Permeability measurements are planned, as are two types of laboratory miniature hydraulic fracturing experiments to investigate the importance of rock fabric (anisotropy and heterogeneity) on near-borehole hydraulic fracture generation. Pre-fracturing numerical simulations with INL’s FALCON discrete element code predicted a fracture radius of 1.2 m for a corresponding injection volume of 1.2 L for the planned fractures, and negligible microseismicity. Field measurements of the stress field by hydraulic fracturing showed that the minimum horizontal stress at the kISMET site averages 21.7 MPa (3146 psi) pointing approximately N-S (356 degrees azimuth) and plunging slightly NNW at 12°. The vertical and horizontal maximum stress are similar in magnitude at 42-44 MPa (6090-6380 psi) for the depths of testing which averaged approximately 1530 m (5030 ft). Hydraulic fractures were remarkably uniform suggesting core-scale and larger rock fabric did not play a role in controlling fracture orientation. Monitoring using ERT and CASSM in the four monitoring boreholes, and passive seismic accelerometer-based measurements in the West Access Drift, was carried out during the generation of a larger fracture (so-called stimulation test) at a depth of 40 m below the invert. ERT was not able to detect the fracture created, nor were the accelerometers in the drift, but microseismicity was detected for first (deepest) hydraulic-fracturing stress measurement. The CASSM data have not yet been analyzed. Analytical solutions suggest fracture radius of the large fracture (stimulation test) was more than 6 m, depending on the unknown amount of leak-off. The kISMET results for stress state are consistent with large-scale mid-continent estimates of stress. Currently we are using the orientation of the stress field we determined to interpret a large number of borehole breakouts recorded in nearby boreholes at SURF to generate a more complete picture of the stress field and its variations at SURF. The efforts on the project have prompted a host of additional follow-on studies that we recommend be carried out at the kISMET site.« less
Prevalence of overweight in children with bone fractures: a case control study.
Valerio, Giuliana; Gallè, Francesca; Mancusi, Caterina; Di Onofrio, Valeria; Guida, Pasquale; Tramontano, Antonino; Ruotolo, Edoardo; Liguori, Giorgio
2012-10-22
Children's fractures have been enlisted among orthopaedics complaints of childhood obesity. Unhealthy lifestyle behaviours may contribute to increased risk. This study described the prevalence of overweight/obesity in children and adolescents reporting a recent fracture in relation to gender, dynamic of trauma, and site of fracture. Four-hundred-forty-nine children and adolescents with fracture and 130 fracture-free controls were recruited from a large children's hospital. The interaction between overweight and gender, dynamic of trauma, site of fracture was explored. Sports participation, television viewing, and calcium intake were also investigated. Overweight/obesity rate was increased in girls with fracture either at the upper or the lower limb (p= 0.004), while it was increased only in boys with fracture at the lower limb (p <0.02). Overweight/obesity rate did not differ between groups with low or moderate trauma. TV viewing ≥ 2 hrs was more frequent in children with fractures than controls (61.5% vs 34.5%, p =0.015) in the overweight/obese group. The increased prevalence of overweight/obesity in children with fractures is related to gender and site of fracture. Higher levels of sedentary behaviours characterize overweight children reporting fractures.
Prevalence of overweight in children with bone fractures: a case control study
2012-01-01
Background Children's fractures have been enlisted among orthopaedics complaints of childhood obesity. Unhealthy lifestyle behaviours may contribute to increased risk. This study described the prevalence of overweight/obesity in children and adolescents reporting a recent fracture in relation to gender, dynamic of trauma, and site of fracture. Methods Four-hundred-forty-nine children and adolescents with fracture and 130 fracture-free controls were recruited from a large children’s hospital. The interaction between overweight and gender, dynamic of trauma, site of fracture was explored. Sports participation, television viewing, and calcium intake were also investigated. Results Overweight/obesity rate was increased in girls with fracture either at the upper or the lower limb (p= 0.004), while it was increased only in boys with fracture at the lower limb (p <0.02). Overweight/obesity rate did not differ between groups with low or moderate trauma. TV viewing ≥ 2 hrs was more frequent in children with fractures than controls (61.5% vs 34.5%, p =0.015) in the overweight/obese group. Conclusions The increased prevalence of overweight/obesity in children with fractures is related to gender and site of fracture. Higher levels of sedentary behaviours characterize overweight children reporting fractures. PMID:23088687
Analysis of the causes of dental implant fracture: A retrospective clinical study.
Stoichkov, Biser; Kirov, Dimitar
2018-01-01
Fracture of osseointegrated dental implants is the most severe mechanical complication. The aim of the present study was to analyze possible causative factors for implant body fracture. One hundred and one patients with 218 fitted implants and a follow-up period of 3 to 10 years were studied. Factors associated with biomechanical and physiologic overloading such as parafunctional activity (eg, bruxism), occlusion, and cantilevers, and factors related to the planning of the dental prosthesis, available bone volume, implant area, implant diameter, number of implants, and their inclination were tracked. The impact of their effect was analyzed using the Bonferroni-corrected post-hoc Mann-Whitney test for each group. The incidence of dental implant fracture was 2.3% in the investigated cases. Improper treatment planning, bruxism, and time of the complication setting in were the main factors leading to this complication. Typical size effect was established only for available bruxism, occlusal errors, and their activity duration. These complications were observed most often with single crown prostheses, and in combination with parafunctional activities such as bruxism and lack of implant-protected occlusion. Occlusal overload due to bruxism or inappropriate or inadequate occlusion as a single factor or a combination of these factors during the first years after the functional load can cause implant fracture. Fracture of the implant body more frequently occurred with single crowns than with other implant-supported fixed dental prostheses.
Determination of Fracture Patterns in Glass and Glassy Polymers.
Baca, Allison C; Thornton, John I; Tulleners, Frederic A
2016-01-01
The study of fractures of glass, glassy-type materials, and plastic has long been of interest to the forensic community. The focus of this interest has been the use of glass and polymer fractures to associate items of evidence under the assumption that each fracture is different. Generally, it is well-accepted that deviations exist; however, the emphasis has been on classifying and predicting fracture rather than determining that each fracture is different. This study documented the controlled fracture patterns of 60 glass panes, 60 glass bottles, and 60 plastic tail light lens covers using both dynamic impact and static pressure methods under closely controlled conditions. Each pattern was intercompared, and based on the limited specimens tested in this study, the results illustrate that the fracture patterns are different. Further repetitive studies, under controlled conditions, will be needed to provide more statistical significance to the theory that each fracture forms a nonreproducible fracture pattern. © 2015 American Academy of Forensic Sciences.
Schulz-Drost, Stefan; Oppel, Pascal; Grupp, Sina; Schmitt, Sonja; Carbon, Roman Th.; Mauerer, Andreas; Hennig, Friedrich F.; Buder, Thomas
2015-01-01
Different ways to stabilize a sternal fracture are described in literature. Respecting different mechanisms of trauma such as the direct impact to the anterior chest wall or the flexion-compression injury of the trunk, there is a need to retain each sternal fragment in the correct position while neutralizing shearing forces to the sternum. Anterior sternal plating provides the best stability and is therefore increasingly used in most cases. However, many surgeons are reluctant to perform sternal osteosynthesis due to possible complications such as difficulties in preoperative planning, severe injuries to mediastinal organs, or failure of the performed method. This manuscript describes one possible safe way to stabilize different types of sternal fractures in a step by step guidance for anterior sternal plating using low profile locking titanium plates. Before surgical treatment, a detailed survey of the patient and a three dimensional reconstructed computed tomography is taken out to get detailed information of the fracture’s morphology. The surgical approach is usually a midline incision. Its position can be described by measuring the distance from upper sternal edge to the fracture and its length can be approximated by the summation of 60 mm for the basis incision, the thickness of presternal soft tissue and the greatest distance between the fragments in case of multiple fractures. Performing subperiosteal dissection along the sternum while reducing the fracture, using depth limited drilling, and fixing the plates prevents injuries to mediastinal organs and vessels. Transverse fractures and oblique fractures at the corpus sterni are plated longitudinally, whereas oblique fractures of manubrium, sternocostal separation and any longitudinally fracture needs to be stabilized by a transverse plate from rib to sternum to rib. Usually the high convenience of a patient is seen during follow up as well as a precise reconstruction of the sternal morphology. PMID:25590989
Dagnino, Giulio; Georgilas, Ioannis; Tarassoli, Payam; Atkins, Roger; Dogramadzi, Sanja
2016-03-01
Joint fracture surgery quality can be improved by robotic system with high-accuracy and high-repeatability fracture fragment manipulation. A new real-time vision-based system for fragment manipulation during robot-assisted fracture surgery was developed and tested. The control strategy was accomplished by merging fast open-loop control with vision-based control. This two-phase process is designed to eliminate the open-loop positioning errors by closing the control loop using visual feedback provided by an optical tracking system. Evaluation of the control system accuracy was performed using robot positioning trials, and fracture reduction accuracy was tested in trials on ex vivo porcine model. The system resulted in high fracture reduction reliability with a reduction accuracy of 0.09 mm (translations) and of [Formula: see text] (rotations), maximum observed errors in the order of 0.12 mm (translations) and of [Formula: see text] (rotations), and a reduction repeatability of 0.02 mm and [Formula: see text]. The proposed vision-based system was shown to be effective and suitable for real joint fracture surgical procedures, contributing a potential improvement of their quality.
Trads, Mette; Deutch, Søren Rasmussen; Pedersen, Preben Ulrich
2017-09-07
The prevalence of constipation in the general population is 2-28%. Patients with constipation report symptoms of abdominal pain, bloating, nausea, straining to defecate and general discomfort. Strategies for preventing constipation include laxatives, exercise and increased fluid and fibre intake, but life style adjustments, such as exercise, eating more fibres and drinking more fluids, were not considered a solution by older patients. Previous studies have shown that actively involving patients through individualised care and support increases patients' outcome. To test the efficacy of a nursing intervention based on active patient involvement including individualised nursing care plans and daily dialogues for patients with hip fractures in preventing constipation after surgery. A quasi-experimental design was applied. Inclusion criteria hip fracture needing surgery, understand Danish. Exclusion criteria dementia, gastrointestinal disease. A total of 186 patients were included and 155 completed. An admission interview including Constipation Risk Assessment Scale was undertaken. On that basis an individualised nursing care plan was made. At admission, discharge and 30 days after surgery constipation, intake of fibres and fluid were measured. The Bristol Stool Scale and Rasmussen's scale were used to measure constipation. Patients in the control group received standard care of the ward. After 30 days constipation rates for patients in the intervention group were significantly lower than for patients in the control group (p = 0.042). The fibre intakes and fluid intakes were significantly higher in the intervention group (p ≤ 0.001). The effect of liquid intake was statistically significant (OR = 1.1, 95% CI: 1.0-1.2). Likewise, the effect of fibre intake was statistically significant; the odds of constipation decreased with increasing fibre intake (OR = 0.4, 95% CI: 0.2-0.8). Patients with hip fractures that were actively involved in their own care in preventing constipation were significantly less constipated 30 days after surgery than control patients. Increases in fluid and fibre intakes had significant effects on reducing the risk of developing constipation. © 2017 Nordic College of Caring Science.
Fracture control for the Oman India Pipeline
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bruno, T.V.
1996-12-31
This paper describes the evaluation of the resistance to fracture initiation and propagation for the high-strength, heavy-wall pipe required for the Oman India Pipeline (OIP). It discusses the unique aspects of this pipeline and their influence on fracture control, reviews conventional fracture control design methods, their limitations with regard to the pipe in question, the extent to which they can be utilized for this project, and other approaches being explored. Test pipe of the size and grade required for the OIP show fracture toughness well in excess of the minimum requirements.
Thomas, Thaddeus P.; Anderson, Donald D.; Willis, Andrew R.; Liu, Pengcheng; Frank, Matthew C.; Marsh, J. Lawrence; Brown, Thomas D.
2011-01-01
Reconstructing highly comminuted articular fractures poses a difficult surgical challenge, akin to solving a complicated three-dimensional (3D) puzzle. Pre-operative planning using CT is critically important, given the desirability of less invasive surgical approaches. The goal of this work is to advance 3D puzzle solving methods toward use as a pre-operative tool for reconstructing these complex fractures. Methodology for generating typical fragmentation/dispersal patterns was developed. Five identical replicas of human distal tibia anatomy, were machined from blocks of high-density polyetherurethane foam (bone fragmentation surrogate), and were fractured using an instrumented drop tower. Pre- and post-fracture geometries were obtained using laser scans and CT. A semi-automatic virtual reconstruction computer program aligned fragment native (non-fracture) surfaces to a pre-fracture template. The tibias were precisely reconstructed with alignment accuracies ranging from 0.03-0.4mm. This novel technology has potential to significantly enhance surgical techniques for reconstructing comminuted intra-articular fractures, as illustrated for a representative clinical case. PMID:20924863
Havlůj, L; Džupa, V; Gürlich, R
2017-01-01
Current polytrauma management is multidisciplinary, with Damage Control Surgery (DCS), Damage Control Orthopaedics (DCO) and Damage Control Resuscitation (DCR) being applied in the first few hours after injury. The most severe group of polytrauma patients are those with circulatory instability and massive blood loss as a consequence of unstable pelvic fractures. In treating these patients, of crucial importance is the speed and quality of stabilisation of pelvic fracture fragments. The authors present two case reports of polytrauma patients with unstable pelvic fractures, in whom open reduction and internal fixation was performed on the anterior fracture segment through extended laparotomy in order to stop bleeding into the abdominopelvic cavity as part of the DCS approach. Key words: exsanguination, polytrauma, unstable pelvic fracture, plate fixation.
Assessment of Surrogate Fractured Rock Networks for Evidence of Complex Behavior
NASA Astrophysics Data System (ADS)
Wood, T. R.; McJunkin, T. R.; Podgorney, R. K.; Glass, R. J.; Starr, R. C.; Stoner, D. L.; Noah, K. S.; LaViolette, R. A.; Fairley, J.
2001-12-01
A complex system or complex process is -"one whose properties are not fully explained by an understanding of its component parts". Results from field experiments conducted at the Hell's Half-Acre field site (Arco, Idaho) suggest that the flow of water in an unsaturated, fractured medium exhibits characteristics of a complex process. A series of laboratory studies is underway with sufficient rigor to determine if complex behavior observed in the field is in fact a fundamental characteristic of water flow in unsaturated, fractured media. As an initial step, a series of four duplicate experiments has been performed using an array of bricks to simulate fractured, unsaturated media. The array consisted of 12 limestone blocks cut to uniform size (5cm x 7 cm x 30 cm) stacked on end 4 blocks wide and 3 blocks high with the interfaces between adjacent blocks representing 3 vertical fractures intersecting 2 horizontal fractures. Water was introduced at three point sources on the upper boundary of the model at the top of the vertical fractures. Water was applied under constant flux at a rate below the infiltration capacity of the system, thus maintaining unsaturated flow conditions. Water was collected from the lower boundary via fiberglass wicks at the bottom of each fracture. An automated system acquired and processed water inflow and outflow data and time-lapse photographic data during each of the 72-hour tests. From these experiments, we see that a few general statements can be made on the overall advance of the wetting front in the surrogate fracture networks. For instance, flow generally converged with depth to the center fracture in the bottom row of bricks. Another observation is that fracture intersections integrate the steady flow in overlying vertical fractures and allow or cause short duration high discharge pulses or "avalanches" of flow to quickly traverse the fracture network below. Smaller scale tests of single fracture and fracture intersections are underway to evaluate a wide array of unit processes that are believed to contribute to complex behavior. Examples of these smaller scale experiments include the role of fracture intersections in integrating a steady inflow to generate giant fluctuations in network discharge; the influence of microbe growth on flow; and the role of geochemistry in alterations of flow paths. Experiments are planned at the meso and field scale to document and understand the controls on self-organized behavior. Modeling is being conducted in parallel with the experiments to understand how simulations can be improved to capture the complexity of fluid flow in fractured rock vadose zones and to make better predictions of contaminant transport.
Change in fracture risk and fracture pattern after bariatric surgery: nested case-control study.
Rousseau, Catherine; Jean, Sonia; Gamache, Philippe; Lebel, Stéfane; Mac-Way, Fabrice; Biertho, Laurent; Michou, Laëtitia; Gagnon, Claudia
2016-07-27
To investigate whether bariatric surgery increases the risk of fracture. Retrospective nested case-control study. Patients who underwent bariatric surgery in the province of Quebec, Canada, between 2001 and 2014, selected using healthcare administrative databases. 12 676 patients who underwent bariatric surgery, age and sex matched with 38 028 obese and 126 760 non-obese controls. Incidence and sites of fracture in patients who had undergone bariatric surgery compared with obese and non-obese controls. Fracture risk was also compared before and after surgery (index date) within each group and by type of surgery from 2006 to 2014. Multivariate conditional Poisson regression models were adjusted for fracture history, number of comorbidities, sociomaterial deprivation, and area of residence. Before surgery, patients undergoing bariatric surgery (9169 (72.3%) women; mean age 42 (SD 11) years) were more likely to fracture (1326; 10.5%) than were obese (3065; 8.1%) or non-obese (8329; 6.6%) controls. A mean of 4.4 years after surgery, bariatric patients were more susceptible to fracture (514; 4.1%) than were obese (1013; 2.7%) and non-obese (3008; 2.4%) controls. Postoperative adjusted fracture risk was higher in the bariatric group than in the obese (relative risk 1.38, 95% confidence interval 1.23 to 1.55) and non-obese (1.44, 1.29 to 1.59) groups. Before surgery, the risk of distal lower limb fracture was higher, upper limb fracture risk was lower, and risk of clinical spine, hip, femur, or pelvic fractures was similar in the bariatric and obese groups compared with the non-obese group. After surgery, risk of distal lower limb fracture decreased (relative risk 0.66, 0.56 to 0.78), whereas risk of upper limb (1.64, 1.40 to 1.93), clinical spine (1.78, 1.08 to 2.93), pelvic, hip, or femur (2.52, 1.78 to 3.59) fractures increased. The increase in risk of fracture reached significance only for biliopancreatic diversion. Patients undergoing bariatric surgery were more likely to have fractures than were obese or non-obese controls, and this risk remained higher after surgery. Fracture risk was site specific, changing from a pattern associated with obesity to a pattern typical of osteoporosis after surgery. Only biliopancreatic diversion was clearly associated with fracture risk; however, results for Roux-en-Y gastric bypass and sleeve gastrectomy remain inconclusive. Fracture risk assessment and management should be part of bariatric care. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Novais, Eduardo N.; Carry, Patrick M.; Mark, Bryan J.; Sayan, DE; Miller, Nancy H.
2016-01-01
Objective To identify factors predictive of the risk of conversion from closed to open reduction. Methods ICD-9 codes were used to identify completely displaced pediatric supracondylar humerus fractures that underwent planned closed reduction and percutaneous pinning. Clinical and radiographic variables were retrospectively collected. Results Compared to posterior extension fractures, flexion [Risk Ratio (RR): 34.1, 95% CI: 8.1 to 143.6, p<0.0001] and posterolateral extension [RR: 6.0, 95% CI: 1.3 to 27.5, p=0.0221] fractures were significantly more likely to undergo conversion from closed to open reduction. Conclusions The direction of displacement should be considered during the pre-operative evaluation of supracondylar fractures. PMID:27035497
Määttä, M.; Macdonald, H. M.; Mulpuri, K.
2016-01-01
Summary Forearm fractures are common during growth. We studied bone strength in youth with a recent forearm fracture. In girls, suboptimal bone strength was associated with fractures. In boys, poor balance and physical inactivity may lead to fractures. Prospective studies will confirm these relationships and identify targets for prevention strategies. Introduction The etiology of pediatric forearm fractures is unclear. Thus, we examined distal radius bone strength, microstructure, and density in children and adolescents with a recent low- or moderate-energy forearm fracture and those without forearm fractures. Methods We assessed the non-dominant (controls) and non-fractured (cases) distal radius (7 % site) using high-resolution peripheral quantitative computed tomography (HR-pQCT) (Scanco Medical AG) in 270 participants (girls: cases n=47, controls n=61 and boys: cases n=88, controls n=74) aged 8–16 years. We assessed standard anthropometry, maturity, body composition (dual energy X-ray absorptiometry (DXA), Hologic QDR 4500 W) physical activity, and balance. We fit sex-specific logistic regression models for each bone outcome adjusting for maturity, ethnicity, height, and percent body fat. Results In girls, impaired bone strength (failure load, ultimate stress) and a high load-to-strength ratio were associated with low-energy fractures (odds ratios (OR) 2.8–4.3). Low total bone mineral density (Tt.BMD), bone volume ratio, trabecular thickness, and cortical BMD and thickness were also associated with low-energy fractures (ORs 2.0–7.0). In boys, low Tt.BMD, but not bone strength, was associated with low-energy fractures (OR=1.8). Boys with low-energy fractures had poor balance and higher percent body fat compared with controls (p<0.05). Boys with fractures (both types) were less active than controls (p<0.05). Conclusions Forearm fracture etiology appears to be sex-specific. In girls, deficits in bone strength are associated with fractures. In boys, a combination of poor balance, excess body fat, and low physical activity may lead to fractures. Prospective studies are needed to confirm these relationships and clarify targets for prevention strategies. PMID:25572041
Ekblom-Kullberg, S; Kautiainen, H; Alha, P; Leirisalo-Repo, M; Julkunen, H
2013-01-01
To study risk factors for symptomatic bone fractures in patients with systemic lupus erythematosus (SLE) and to compare the frequency of fractures between SLE patients and population controls. The study included 222 SLE patients [mean age 47.0 years, disease duration 13.1 years, 204 (92%) women] and 720 population controls living in the metropolitan area of Helsinki. The history of symptomatic bone fractures in SLE patients and controls was recorded by interview, and demographic and clinical data of SLE patients were obtained by interview, clinical examination, and chart review. A history of at least one symptomatic bone fracture was recorded in 93 (42%) of all 222 patients with SLE. The risk of any fracture in 204 women with SLE compared to controls was 1.8 [95% confidence interval (CI) 1.3-2.4] and fractures in the ankle, hip, and vertebral column were more common than in female controls, with odds ratios (ORs) of 2.0 (95% CI 1.1-3.7), 5.1 (95% CI 1.2-21.5), and 4.0 (95% CI 1.8-8.6), respectively. In 18 men with SLE, compared to male controls, no difference in the frequency of fractures was observed (OR 0.7, 95% CI 0.3-2.0). Risk factors for bone fractures in women with SLE were age (p = 0.008), comorbidity (p = 0.050), and the duration of corticosteroid use (p = 0.025). Symptomatic bone fractures, especially in the ankle, hip, and vertebral column, are common in women with SLE. Special attention should be paid to preventing fractures in elderly female patients with comorbidities and a long duration of corticosteroid use.
Ankle fracture spur sign is pathognomonic for a variant ankle fracture.
Hinds, Richard M; Garner, Matthew R; Lazaro, Lionel E; Warner, Stephen J; Loftus, Michael L; Birnbaum, Jacqueline F; Burket, Jayme C; Lorich, Dean G
2015-02-01
The hyperplantarflexion variant ankle fracture is composed of a posterior tibial lip fracture with posterolateral and posteromedial fracture fragments separated by a vertical fracture line. This infrequently reported injury pattern often includes an associated "spur sign" or double cortical density at the inferomedial tibial metaphysis. The objective of this study was to quantitatively establish the association of the ankle fracture spur sign with the hyperplantarflexion variant ankle fracture. Our clinical database of operative ankle fractures was retrospectively reviewed for the incidence of hyperplantarflexion variant and nonvariant ankle fractures as determined by assessment of injury radiographs, preoperative advanced imaging, and intraoperative observation. Injury radiographs were then evaluated for the presence of the spur sign, and association between the spur sign and variant fractures was analyzed. The incidence of the hyperplantarflexion variant fracture among all ankle fractures was 6.7% (43/640). The spur sign was present in 79% (34/43) of variant fractures and absent in all nonvariant fractures, conferring a specificity of 100% in identifying variant fractures. Positive predictive value and negative predictive value were 100% and 99%, respectively. The ankle fracture spur sign was pathognomonic for the hyperplantarflexion variant ankle fracture. It is important to identify variant fractures preoperatively as patient positioning, operative approach, and fixation construct of variant fractures often differ from those employed for osteosynthesis of nonvariant fractures. Identification of the spur sign should prompt acquisition of advanced imaging to formulate an appropriate operative plan to address the variant fracture pattern. Level III, retrospective comparative study. © The Author(s) 2014.
Shyu, Yea-Ing L; Liang, Jersey; Tseng, Ming-Yueh; Li, Hsiao-Juan; Wu, Chi-Chuan; Cheng, Huey-Shinn; Chou, Shih-Wei; Chen, Ching-Yen; Yang, Ching-Tzu
2016-04-01
Little evidence is available on the longer-term effects (beyond 12 months) of intervention models consisting of hip fracture-specific care in conjunction with management of malnutrition, depression, and falls. To compare the relative effects of an interdisciplinary care, and a comprehensive care programme with those of usual care for elderly patients with a hip fracture on self-care ability, health care use, and mortality. Randomised experimental trial. A 3000-bed medical centre in northern Taiwan. Patients with hip fracture aged 60 years or older (N=299). Patients were randomly assigned to three groups: comprehensive care (n=99), interdisciplinary care (n=101), and usual care (control) (n=99). Usual care entailed only one or two in-hospital rehabilitation sessions. Interdisciplinary care included not only hospital rehabilitation, but also geriatric consultation, discharge planning, and 4-month in-home rehabilitation. Building upon interdisciplinary care, comprehensive care extended in-home rehabilitation to 12 months and added management of malnutrition and depressive symptoms, and fall prevention. Patients' self-care ability was measured by activities of daily living and instrumental activities of daily living using the Chinese Barthel Index and Chinese version Instrumental Activities of Daily Living scale, respectively. Outcomes were assessed before discharge, and 1, 3, 6, 12, 18, 24 months following hip fracture. Hierarchical linear models were used to analyse health outcomes and health care utilisation, including emergency department visit and hospital re-admission. The comprehensive care group had better performance trajectories for both measures of activities of daily living and fewer emergency department visits than the usual care group, but no difference in hospital readmissions. The interdisciplinary care and usual care groups did not differ in trajectories of self-care ability and service utilisation. The three groups did not differ in mortality during the 2-year follow-up. Comprehensive care, with enhanced rehabilitation, management of malnutrition and depressive symptoms, and fall prevention, improved self-care ability and decreased emergency department visits for elders up to 2 years after hip-fracture surgery, above and beyond the effects of usual care and interdisciplinary care. Copyright © 2015 Elsevier Ltd. All rights reserved.
A close examination of healthcare expenditures related to fractures.
Kilgore, Meredith L; Curtis, Jeffrey R; Delzell, Elizabeth; Becker, David J; Arora, Tarun; Saag, Kenneth G; Morrisey, Michael A
2013-04-01
This study evaluated reasons for healthcare expenditures both before and after the occurrence of fractures among Medicare beneficiaries. In a previous study we examined healthcare expenditures in the 6 months before and after fractures. The difference-"incremental" expenditures-provides one estimate of the potentially avoidable costs associated with fractures. We constructed a second estimate of the cost burden-"attributable" expenditures-using only those costs recorded in claims with fracture diagnosis codes. Attributable expenditures accounted for only 24% to 60% of incremental expenditures, depending on the fracture site. We examined health care expenditures between 1999 and 2005 among Medicare beneficiaries who experienced fractures (cases) and among beneficiaries who did not experience fractures (controls), matched to cases on age, race, and sex. We also examined healthcare expenditures for cases and controls for 24 months prior to the fracture index date. When expenditures associated with diagnoses for aftercare, joint pain, and osteoporosis, other musculoskeletal diagnoses, pneumonia, and pressure ulcers were included, the proportion of incremental costs directly attributable to fracture care rose to 72% to 88%. Expenditures prior to fracture were higher for cases than controls, and the rate of increase accelerated over the 12 months prior to the hip fracture. Our findings confirm that the original incremental cost analysis constituted a satisfactory method for estimating avoidable costs associated with fractures. We also conclude that those with fractures had much higher and growing healthcare expenditures in the 12 months prior to the event, compared with age-, race-, and sex-matched controls. This suggests that patterns of healthcare services utilization may provide a means to improve fracture prediction rules. Copyright © 2013 American Society for Bone and Mineral Research.
Lenza, Mário; Faloppa, Flávio
2015-05-07
This review covers two conditions: acute clavicle fractures and non-union resulting from failed fracture healing. Clavicle (collarbone) fractures account for around 4% of all fractures. While treatment for these fractures is usually non-surgical, some types of clavicular fractures, as well as non-union of the middle third of the clavicle, are often treated surgically. This is an update of a Cochrane review first published in 2009. To evaluate the effects (benefits and harms) of different methods of surgical treatment for acute fracture or non-union of the middle third of the clavicle. We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (27 June 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 5), MEDLINE (1966 to June week 3 2014), EMBASE (1988 to 2014 week 25), LILACS (1982 to 27 June 2014), trial registries and reference lists of articles. We applied no language or publication restrictions. We considered randomised and quasi-randomised controlled trials evaluating any surgical intervention for treating people with fractures or non-union of the middle third of the clavicle. The primary outcomes were shoulder function or disability, pain and treatment failure (measured by the number of participants who had undergone or were being considered for a non-routine secondary surgical intervention for symptomatic non-union, malunion or other complications). Two review authors selected eligible trials, independently assessed risk of bias and cross-checked data. Where appropriate, we pooled results of comparable trials. We included seven trials in this review with 398 participants. Four trials were new in this update.The four new trials (160 participants) compared intramedullary fixation with open reduction and internal fixation with plate for treating acute middle third clavicle fractures in adults. Low quality evidence from the four trials indicated that intramedullary fixation did not result in a clinically important improvement in upper arm function (despite a statistically significant difference in its favour: standardised mean difference 0.45, 95% confidence interval (CI) 0.08 to 0.81; 120 participants, three trials) at long term follow-up of six months or more. Very low quality evidence indicated little difference between intramedullary fixation and plate fixation in pain (one trial), treatment failure resulting in non-routine surgery (2/68 with intramedullary fixation vs. 3/65 with plate fixation; risk ratio 0.69, 95% CI 0.16 to 2.97, four trials) or time to clinical fracture consolidation (three trials). There was very low quality evidence of a lower incidence of participants with adverse events (mainly infection, poor cosmetic result and symptomatic hardware) in the intramedullary fixation group (18/68 with intramedullary fixation vs. 27/65 with plate fixation; RR 0.64, 95% CI 0.39 to 1.03) but the CI of the pooled results also included the small possibility of a lower incidence in the plate fixation group. None of the four trials reported on quality of life or return to previous activities. Evidence is pending from two ongoing trials, with planned recruitment of 245 participants, testing this comparison.There was low or very low quality evidence from three small trials, each testing a different comparison. The three trials had design features that carried a high risk of bias, potentially limiting the reliability of their findings. Low-contact dynamic compression plates appeared to be associated with significantly better upper-limb function throughout the year following surgery, earlier fracture union and return to work, and a reduced incidence of implant-associated symptoms when compared with a standard dynamic compression plate in 36 adults with symptomatic non-union of the middle third of the clavicle. One quasi-randomised trial (69 participants) compared Knowles pin versus a plate for treating middle third clavicle fractures or non-union. Knowles pins appeared to be associated with lower pain levels and use of postoperative analgesics and a reduced incidence of implant-associated symptoms. One study (133 participants) found that a three-dimensional technique for fixation with a reconstruction plate was associated with a significantly lower incidence of symptomatic delayed union than a standard superior position surgical approach. Evidence is pending from two ongoing trials, with planned recruitment of 130 participants, comparing anterior versus superior plates for acute fractures. There is very limited and low quality evidence available from randomised controlled trials regarding the effectiveness of different methods of surgical fixation of fractures and non-union of the middle third of the clavicle. The evidence from four ongoing trials is likely to inform practice for the comparisons of intramedullary versus plate fixation and anterior versus superior plates for acute fractures in a future update. Further randomised trials are warranted, but in order to optimise research effort, these should be preceded by research that aims to identify priority questions.
WITHDRAWN: Resorbable versus titanium plates for facial fractures.
Dorri, Mojtaba; Oliver, Richard
2018-05-23
Rigid internal fixation of the jaw bones is a routine procedure for the management of facial fractures. Titanium plates and screws are routinely used for this purpose. The limitations of this system has led to the development of plates manufactured from bioresorbable materials which, in some cases, omits the necessity for the second surgery. However, concerns remain about the stability of fixation and the length of time required for their degradation and the possibility of foreign body reactions. To compare the effectiveness of bioresorbable fixation systems with titanium systems for the management of facial fractures. We searched the following databases: The Cochrane Oral Health Group's Trials Register (to 20th August 2008), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 3), MEDLINE (1950 to 20th August 2008), EMBASE (from 1980 to 20th August 2008), http://www.clinicaltrials.gov/ and http://www.controlled-trials.com (to 20th August 2008). Randomised controlled trials comparing resorbable versus titanium fixation systems used for facial fractures. Retrieved studies were independently screened by two review authors. Results were to be expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals. Heterogeneity was to be investigated including both clinical and methodological factors. The search strategy retrieved 53 potentially eligible studies. None of the retrieved studies met our inclusion criteria and all were excluded from this review. One study is awaiting classification as we failed to obtain the full text copy. Three ongoing trials were retrieved, two of which were stopped before recruiting the planned number of participants. In one study, the excess complications in the resorbable arm was declared as the reason for stopping the trial. This review illustrates that there are no published randomised controlled clinical trials relevant to this review question. There is currently insufficient evidence for the effectiveness of resorbable fixation systems compared with conventional titanium systems for facial fractures. The findings of this review, based on the results of the aborted trials, do not suggest that resorbable plates are as effective as titanium plates. In future, the results of ongoing clinical trials may provide high level reliable evidence for assisting clinicians and patients for decision making. Trialists should design their studies accurately and comprehensively to meet the aims and objectives defined for the study.
Cochlear Implantation after Bilateral Transverse Temporal Bone Fractures
Shin, Jong-Heon; Park, SooChan; Baek, Sam-Hyun
2008-01-01
Patients deafened by a severe head injury are rarely encountered. We report a case of a 65-yr-old man with bilateral transverse temporal bone fractures due to head injury. He underwent cochlear implant and achieved a satisfactory auditory rehabilitation. Imaging studies of temporal bone before performing a cochlear implantation provide important information on a patient with bilateral temporal bone fractures. Cochlear implantations with careful planning in such a patient may be a very effective method for aural rehabilitation. PMID:19434252
Rapid Geriatric Assessment of Hip Fracture.
Zanker, Jesse; Duque, Gustavo
2017-08-01
A comprehensive geriatric assessment, combined with a battery of imaging and blood tests, should be able to identify those hip fracture patients who are at higher risk of short- and long-term complications. This comprehensive assessment should be followed by the implementation of a comprehensive multidimensional care plan aimed to prevent negative outcomes in the postoperative period (short and long term), thus assuring a safe and prompt functional recovery while also preventing future falls and fractures. Copyright © 2017 Elsevier Inc. All rights reserved.
Fracture Risk and Areal Bone Mineral Density in Adolescent Females with Anorexia Nervosa
Faje, Alexander T.; Fazeli, Pouneh K.; Miller, Karen K.; Katzman, Debra K.; Ebrahimi, Seda; Lee, Hang; Mendes, Nara; Snelgrove, Deirdre; Meenaghan, Erinne; Misra, Madhusmita; Klibanski, Anne
2014-01-01
Objective To (i) compare fracture prevalence in adolescent females with anorexia nervosa (AN) vs. normal-weight controls and (ii) examine whether reductions in areal bone mineral density (aBMD) predict fracture risk in females with AN. Methods 418 females (310 with active AN and 108 normal-weight controls) 12–22 years old were studied cross-sectionally. Lifetime fracture history was recorded by a physician during participant interviews. Body composition and aBMD measurements of the whole body, whole body less head, lumbar spine, and hip were assessed by dual-energy x-ray absorptiometry (DXA), and bone mineral apparent density (BMAD) was calculated for the lumbar spine. Results Participants with AN and normal-weight controls did not differ for chronological age, sexual maturity, or height. The lifetime prevalence of prior fracture was 59.8% higher in those with AN compared to controls (31.0 % versus 19.4 %, p = 0.02), and the fracture incidence rate peaked in our cohort after the diagnosis of AN. Lower aBMD and lumbar BMAD were not associated with a higher prevalence of fracture in the AN or control group on univariate or multivariate analyses. Compared to controls, fracture prevalence was significantly higher in the subgroup of girls with AN who had normal aBMD or only modest reductions of aBMD (Z-scores > −1 or −1.5). Discussion This is the first study to show that the risk of fracture during childhood and adolescence is significantly higher in patients with AN than in normal-weight controls. Fracture prevalence is increased in this cohort of subjects with AN even without significant reductions in aBMD. PMID:24430890
Fracture risk and areal bone mineral density in adolescent females with anorexia nervosa.
Faje, Alexander T; Fazeli, Pouneh K; Miller, Karen K; Katzman, Debra K; Ebrahimi, Seda; Lee, Hang; Mendes, Nara; Snelgrove, Deirdre; Meenaghan, Erinne; Misra, Madhusmita; Klibanski, Anne
2014-07-01
To (i) compare fracture prevalence in adolescent females with anorexia nervosa (AN) versus normal-weight controls and (ii) examine whether reductions in areal bone mineral density (aBMD) predict fracture risk in females with AN. Four-hundred eighteen females (310 with active AN and 108 normal-weight controls) 12- to 22-years-old were studied cross-sectionally. Lifetime fracture history was recorded by a physician during participant interviews. Body composition and aBMD measurements of the whole body, whole body less head, lumbar spine, and hip were assessed by dual-energy X-ray absorptiometry, and bone mineral apparent density (BMAD) was calculated for the lumbar spine. Participants with AN and normal-weight controls did not differ for chronological age, sexual maturity, or height. The lifetime prevalence of prior fracture was 59.8% higher in those with AN as compared to controls (31.0% vs. 19.4%, p = 0.02), and the fracture incidence rate peaked in our cohort after the diagnosis of AN. Lower aBMD and lumbar BMAD were not associated with a higher prevalence of fracture in the AN or control group on univariate or multivariate analyses. Compared to controls, fracture prevalence was significantly higher in the subgroup of girls with AN who had normal aBMD or only modest reductions of aBMD (Z-scores > -1 or -1.5). This is the first study to show that the risk of fracture during childhood and adolescence is significantly higher in patients with AN than in normal-weight controls. Fracture prevalence is increased in this cohort of participants with AN even without significant reductions in aBMD. © 2014 Wiley Periodicals, Inc.
Solomon, Daniel H; Katz, Jeffrey N; Finkelstein, Joel S; Polinski, Jennifer M; Stedman, Margaret; Brookhart, M Alan; Arnold, Marilyn; Gauthier, Suzanne; Avorn, Jerry
2007-11-01
We conducted a randomized controlled trial within the setting of a large drug benefit plan for Medicare beneficiaries. Primary care physicians and their patients were randomized to usual care, patient intervention only, physician intervention only, or both interventions. There was no difference in the probability of the primary composite endpoint (BMD test or osteoporosis medication) or in either of its components comparing the combined intervention group with usual care (risk ratio = 1.04; 95% CI, 0.85-1.26). Fractures from osteoporosis are associated with substantial morbidity, mortality, and cost. However, only a minority of at-risk older adults receives screening and/or treatment for this condition. We evaluated the effect of educational interventions for osteoporosis targeting at-risk patients, primary care physicians, or both. We conducted a randomized controlled trial within the setting of a large drug benefit plan for Medicare beneficiaries. Primary care physicians and their patients were randomized to usual care, patient intervention only, physician intervention only, or both interventions. The at-risk patients were women >or=65 yr of age, men and women >or=65 yr of age with a prior fracture, and men and women >or=65 yr of age who used oral glucocorticoids. The primary outcome studied was a composite of either undergoing a BMD test or initiating a medication used for osteoporosis. The secondary outcome was a hip, humerus, spine, or wrist fracture. We randomized 828 primary care physicians and their 13,455 eligible at-risk patients into four study arms. Physician and patient characteristics were very similar across all four groups. Across all four groups, the rate of the composite outcome was 10.3 per 100 person-years and did not differ between the usual care and the combined intervention groups (p = 0.5). In adjusted Cox proportional hazards models, there was no difference in the probability of the primary composite endpoint comparing the combined intervention group with usual care (risk ratio = 1.04; 95% CI, 0.85-1.26). There was also no difference in either of the components of the composite endpoint. The probability of fracture during follow-up was 4.2 per 100 person-years and did not differ by treatment assignment (p = 0.9). In this trial, a relatively brief program of patient and/or physician education did not work to improve the management of osteoporosis. More intensive efforts should be considered for future quality improvement programs for osteoporosis.
Micro X-ray CT Imaging of Sediments under Confining Pressure
NASA Astrophysics Data System (ADS)
Schindler, M.; Prasad, M.
2016-12-01
We developed a pressure and temperature control system for use inside the micro X-ray CT scanner Xradia 400. We succeeded in building a pressure vessel that can be pressurized to 34.5 MPa (5000 psi) while being transparent to X-rays. The setup can currently be cooled to -5°C and heated to 40°C. We were able to observe grain damage and porosity reduction due to applied confining pressure in clean quartz sand samples and quartz sand and bentonite samples. By comparing micro CT images at atmospheric pressure and 13.8 MPa (2000 psi) confining pressure, we observed compaction of the samples resulting in grain damage and fracturing of sediment grains (Figure 1). When the confining pressure was decreased some grains experienced further fracturing. The grain damage appears irreversible. Further fracturing of grains in pre-compacted sediment was observed upon repeated confining pressure cycling. We are currently working on feed-throughs for fluid lines and electric wiring to use ultrasonic transducers and pressure control in combination. Further we plan to include pore pressure in addition to confining pressure into the system. The pressure control system in combination with ultrasonic transducers will allow us to visually observe pore scale changes in rock samples while simultaneously identifying their influence on ultrasonic velocities. Such pore-scale changes are usually not taken into account by rock physics models and could help to identify why laboratory data diverges from theoretical models. Further, it is possible to compute compressibility from mCT images at different stress states by image correlation
Dehghan, Niloofar; McKee, Michael D; Jenkinson, Richard J; Schemitsch, Emil H; Stas, Venessa; Nauth, Aaron; Hall, Jeremy A; Stephen, David J; Kreder, Hans J
2016-07-01
The aim of this study was to compare early weightbearing and range of motion (ROM) to nonweightbearing and immobilization in a cast after surgical fixation of unstable ankle fractures. Multicentre randomized controlled trial. Two-level one trauma centers. One hundred ten patients who underwent open reduction and internal fixation of an unstable ankle fracture were recruited and randomized. One of 2 rehabilitation protocols: (1) Early weightbearing (weightbearing and ROM at 2 weeks, Early WB) or (2) Late weightbearing (nonweightbearing and cast immobilization for 6 weeks, Late WB). The primary outcome measure was time to return to work (RTW). Secondary outcome measures included: ankle ROM, SF-36 heath outcome scores, Olerud/Molander ankle function score, and rates of complications. There was no difference in RTW. At 6 weeks postoperatively, patients in the Early WB group had significantly improved ankle ROM (41 vs. 29, P < 0.0001); Olerud/Molander ankle function scores (45 vs. 32, P = 0.0007), and SF-36 scores on both the physical (51 vs. 42, P = 0.008) and mental (66 vs. 54, P = 0.0008) components. There were no differences with regard to wound complications or infections and no cases of fixation failure or loss of reduction. Patients in the Late WB group had higher rates of planned/performed hardware removal due to plate irritation (19% vs. 2%, P = 0.005). Given the convenience for the patient, early improved functional outcome, and the lack of an increased complication rate, we recommend early postoperative weightbearing and ROM in patients with surgically treated ankle fractures. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.
Stress corrosion-controlled rates of mode I fracture propagation in calcareous bedrock
NASA Astrophysics Data System (ADS)
Voigtlaender, Anne; Leith, Kerry; Krautblatter, Michael
2014-05-01
Surface bedrock on natural rock slopes is subject to constant and cyclic environmental stresses (wind, water, wave, ice, seismic or gravitational). Studies indicate that these stresses range up to several hundred kPa, generally too low to cause macroscopic changes in intact rock, although clear evidence of fracture generation, crack propagation and weathering of bedrock illustrates the effect of environmental stresses at the Earth's surface. We suggest that material degradation and its extent, is likely to be controlled by the rate of stress corrosion cracking (SCC). Stress corrosion is a fluid-material reaction, where fluids preferentially react with strained atomic bonds at the tip of developing fractures. Stress corrosion in ferrous and siliceous materials is often accepted as the fracture propagation and degradation rate-controlling process where materials are subject to stresses and fluids. Although evidence for chemical weathering in propagating bedrock fractures is clear in natural environments, the physical system and quantification of stress corrosion in natural rocks is yet to be addressed. Here, we present preliminary data on the relationship between stresses at levels commonly present on natural rock slopes, and material damage resulting from stress corrosion under constant or cyclic tensile loading. We undertake single notch three-point bending tests (SNBT) on fresh calcareous bedrock specimens (1100x100x100mm) over a two-month period. Two beams containing an artificial notch are stressed to 75% of their ultimate strength, and a constant supply of weak acid is applied at the notch tip to enhance chemical reactions. A third, unloaded, beam is also exposed to weak acid in order to elucidate the contribution of stress corrosion cracking to the material degradation. Stresses at the tip of propagating cracks affect the kinetics of the chemical reaction in the specimen exposed to both loading and corrosion, leading to an increase in degradation, and greater stress relaxation. These changes in material properties are monitored using strain gauges, acoustic emission sensors, changes in P-wave velocity, and records of time to failure where appropriate. Our preliminary studies indicate changes in material properties are concentrated in the region of predicted tensile stress intensification. Reactions seem to favourably occur at the stressed bonds around the crack tip. The rate of chemical dissolution and further propagation of the fracture at the notch tip appears to be enhanced by the level of stress applied to the specimen. This provides the foundation for a suite of repeated experiments in which we plan to test corrosion-controlled rates of degradation across a range of loading conditions. The improved understanding into micro-mechanical controls, will contribute to the assessment of rock fall production rates and erosion processes in natural environments as well as natural building stones.
The value of preoperative planning.
Graves, Matt L
2013-10-01
"Better to throw your disasters into the waste paper basket than to consign your patients to the scrap heap" has been a proverb of Jeff Mast, one of the greatest fracture and deformity surgeons in the history of our specialty. Stated slightly more scientifically, one of the major values of simulation is that it allows one to make mistakes in a consequence-free environment. Preoperative planning is the focus of this article. The primary goal is not to provide you with a recipe of how to steps. Rather, the primary goal of this article is to explain why preoperative planning should be standard, to clarify what should be included, and to provide examples of what can happen when planning is ignored. At the end of this, we should all feel the need to approach fracture care more intellectually with forethought, both in our own practices and in our educational system.
NASA Astrophysics Data System (ADS)
Doungkaew, N.; Eichhubl, P.
2015-12-01
Processes of fracture formation control flow of fluid in the subsurface and the mechanical properties of the brittle crust. Understanding of fundamental fracture growth mechanisms is essential for understanding fracture formation and cementation in chemically reactive systems with implications for seismic and aseismic fault and fracture processes, migration of hydrocarbons, long-term CO2 storage, and geothermal energy production. A recent study on crack-seal veins in deeply buried sandstone of east Texas provided evidence for non-linear fracture growth, which is indicated by non-elliptical kinematic fracture aperture profiles. We hypothesize that similar non-linear fracture growth also occurs in other geologic settings, including under higher temperature where solution-precipitation reactions are kinetically favored. To test this hypothesis, we investigate processes of fracture growth in quartzitic sandstone of the Campito Formation, eastern California, by combining field structural observations, thin section petrography, and fluid inclusion microthermometry. Fracture aperture profile measurements of cemented opening-mode fractures show both elliptical and non-elliptical kinematic aperture profiles. In general, fractures that contain fibrous crack-seal cement have elliptical aperture profiles. Fractures filled with blocky cement have linear aperture profiles. Elliptical fracture aperture profiles are consistent with linear-elastic or plastic fracture mechanics. Linear aperture profiles may reflect aperture growth controlled by solution-precipitation creep, with the aperture distribution controlled by solution-precipitation kinetics. We hypothesize that synkinematic crack-seal cement preserves the elliptical aperture profiles of elastic fracture opening increments. Blocky cement, on the other hand, may form postkinematically relative to fracture opening, with fracture opening accommodated by continuous solution-precipitation creep.
Rossol, Melanie; Gygax, Diego; Andritzky-Waas, Juliane; Zheng, Guoyan; Lischer, Christoph J; Zhang, Xuan; Auer, Joerg A
2008-01-01
To (1) evaluate and compare computer-assisted surgery (CAS) with conventional screw insertion (conventional osteosynthesis [COS]) for treatment of equine abaxial distal phalanx fractures; (2) compare planned screw position with actual postoperative position; and (3) determine preferred screw insertion direction. Experimental study. Cadaveric equine limbs (n=32). In 8 specimens each, a 4.5 mm cortex bone screw was inserted in lag fashion in dorsopalmar (plantar) direction using CAS or COS. In 2 other groups of 8, the screws were inserted in opposite direction. Precision of CAS was determined by comparison of planned and actual screw position. Preferred screw direction was also assessed for CAS and COS. In 4 of 6 direct comparisons, screw positioning was significantly better with CAS. Results of precision analysis for screw position were similar to studies published in human medicine. None of evaluated criteria identified a preferred direction for screw insertion. For abaxial fractures of the distal phalanx, superior precision in screw position is achieved with CAS technique compared with COS technique. Abaxial fractures of the distal phalanx lend themselves to computer-assisted implantation of 1 screw in a dorsopalmar (plantar) direction. Because of the complex anatomic relationships, and our results, we discourage use of COS technique for repair of this fracture type.
Use of Organic Nitrates and the Risk of Hip Fracture: A Population-Based Case-Control Study
Pouwels, Sander; Lalmohamed, Arief; van Staa, Tjeerd; Cooper, Cyrus; Souverein, Patrick; Leufkens, Hubertus G.; Rejnmark, Lars; de Boer, Anthonius; Vestergaard, Peter; de Vries, Frank
2010-01-01
Context: Use of organic nitrates has been associated with increased bone mineral density. Moreover, a large Danish case-control study reported a decreased fracture risk. However, the association with duration of nitrate use, dose frequency, and impact of discontinuation has not been extensively studied. Objective: Our objective was to evaluate the association between organic nitrates and hip fracture risk. Methods: A case-control study was conducted using the Dutch PHARMO Record Linkage System (1991–2002, n = 6,763 hip fracture cases and 26,341 controls). Cases had their first admission for hip fracture, whereas controls had not sustained any fracture after enrollment. Current users of organic nitrates were patients who had received a prescription within 90 d before the index date. The analyses were adjusted for disease and drug history. Results: Current use of nitrates was not associated with a decreased risk of hip fracture [adjusted odds ratio (OR) = 0.93; 95% confidence interval (CI) = 0.83–1.04]. Those who used as-needed medication only had a lower risk of hip fracture (adjusted OR = 0.83; 95% CI = 0.63–1.08) compared with users of maintenance medication only (adjusted OR = 1.17; 95% CI = 0.97–1.40). No association was found between duration of nitrate use and fracture risk. Conclusions: Our overall analyses showed that risk of a hip fracture was significantly lower among users of as-needed organic nitrates, when compared with users of maintenance medication. Our analyses of hip fracture risks with duration of use did not further support a beneficial effect of organic nitrates on hip fracture, although residual confounding may have masked beneficial effects. PMID:20130070
Use of organic nitrates and the risk of hip fracture: a population-based case-control study.
Pouwels, Sander; Lalmohamed, Arief; van Staa, Tjeerd; Cooper, Cyrus; Souverein, Patrick; Leufkens, Hubertus G; Rejnmark, Lars; de Boer, Anthonius; Vestergaard, Peter; de Vries, Frank
2010-04-01
Use of organic nitrates has been associated with increased bone mineral density. Moreover, a large Danish case-control study reported a decreased fracture risk. However, the association with duration of nitrate use, dose frequency, and impact of discontinuation has not been extensively studied. Our objective was to evaluate the association between organic nitrates and hip fracture risk. A case-control study was conducted using the Dutch PHARMO Record Linkage System (1991-2002, n = 6,763 hip fracture cases and 26,341 controls). Cases had their first admission for hip fracture, whereas controls had not sustained any fracture after enrollment. Current users of organic nitrates were patients who had received a prescription within 90 d before the index date. The analyses were adjusted for disease and drug history. Current use of nitrates was not associated with a decreased risk of hip fracture [adjusted odds ratio (OR) = 0.93; 95% confidence interval (CI) = 0.83-1.04]. Those who used as-needed medication only had a lower risk of hip fracture (adjusted OR = 0.83; 95% CI = 0.63-1.08) compared with users of maintenance medication only (adjusted OR = 1.17; 95% CI = 0.97-1.40). No association was found between duration of nitrate use and fracture risk. Our overall analyses showed that risk of a hip fracture was significantly lower among users of as-needed organic nitrates, when compared with users of maintenance medication. Our analyses of hip fracture risks with duration of use did not further support a beneficial effect of organic nitrates on hip fracture, although residual confounding may have masked beneficial effects.
Savaridas, T; Wallace, R J; Salter, D M; Simpson, A H R W
2013-09-01
Fracture repair occurs by two broad mechanisms: direct healing, and indirect healing with callus formation. The effects of bisphosphonates on fracture repair have been assessed only in models of indirect fracture healing. A rodent model of rigid compression plate fixation of a standardised tibial osteotomy was used. Ten skeletally mature Sprague-Dawley rats received daily subcutaneous injections of 1 µg/kg ibandronate (IBAN) and ten control rats received saline (control). Three weeks later a tibial osteotomy was rigidly fixed with compression plating. Six weeks later the animals were killed. Fracture repair was assessed with mechanical testing, radiographs and histology. The mean stress at failure in a four-point bending test was significantly lower in the IBAN group compared with controls (8.69 Nmm(-2) (sd 7.63) vs 24.65 Nmm(-2) (sd 6.15); p = 0.017). On contact radiographs of the extricated tibiae the mean bone density assessment at the osteotomy site was lower in the IBAN group than in controls (3.7 mmAl (sd 0.75) vs 4.6 mmAl (sd 0.57); p = 0.01). In addition, histological analysis revealed progression to fracture union in the controls but impaired fracture healing in the IBAN group, with predominantly cartilage-like and undifferentiated mesenchymal tissue (p = 0.007). Bisphosphonate treatment in a therapeutic dose, as used for risk reduction in fragility fractures, had an inhibitory effect on direct fracture healing. We propose that bisphosphonate therapy not be commenced until after the fracture has united if the fracture has been rigidly fixed and is undergoing direct osteonal healing.
Kanna, Rishi Mugesh; Schroeder, Gregory D.; Oner, Frank Cumhur; Vialle, Luiz; Chapman, Jens; Dvorak, Marcel; Fehlings, Michael; Shetty, Ajoy Prasad; Schnake, Klaus; Kandziora, Frank; Vaccaro, Alexander R.
2017-01-01
Study Design: Prospective survey-based study. Objectives: The AO Spine thoracolumbar injury classification has been shown to have good reproducibility among clinicians. However, the influence of spine surgeons’ clinical experience on fracture classification, stability assessment, and decision on management based on this classification has not been studied. Furthermore, the usefulness of varying imaging modalities including radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) in the decision process was also studied. Methods: Forty-one spine surgeons from different regions, acquainted with the AOSpine classification system, were provided with 30 thoracolumbar fractures in a 3-step assessment: first radiographs, followed by CT and MRI. Surgeons classified the fracture, evaluated stability, chose management, and identified reasons for any changes. The surgeons were divided into 2 groups based on years of clinical experience as <10 years (n = 12) and >10 years (n = 29). Results: There were no significant differences between the 2 groups in correctly classifying A1, B2, and C type fractures. Surgeons with less experience had more correct diagnosis in classifying A3 (47.2% vs 38.5% in step 1, 73.6% vs 60.3% in step 2 and 77.8% vs 65.5% in step 3), A4 (16.7% vs 24.1% in step 1, 72.9% vs 57.8% in step 2 and 70.8% vs 56.0% in step3) and B1 injuries (31.9% vs 20.7% in step 1, 41.7% vs 36.8% in step 2 and 38.9% vs 33.9% in step 3). In the assessment of fracture stability and decision on treatment, the less and more experienced surgeons performed equally. The selection of a particular treatment plan varied in all subtypes except in A1 and C type injuries. Conclusion: Surgeons’ experience did not significantly affect overall fracture classification, evaluating stability and planning the treatment. Surgeons with less experience had a higher percentage of correct classification in A3 and A4 injuries. Despite variations between them in classification, the assessment of overall stability and management decisions were similar between the 2 groups. PMID:28815158
Rajasekaran, Shanmuganathan; Kanna, Rishi Mugesh; Schroeder, Gregory D; Oner, Frank Cumhur; Vialle, Luiz; Chapman, Jens; Dvorak, Marcel; Fehlings, Michael; Shetty, Ajoy Prasad; Schnake, Klaus; Kandziora, Frank; Vaccaro, Alexander R
2017-06-01
Prospective survey-based study. The AO Spine thoracolumbar injury classification has been shown to have good reproducibility among clinicians. However, the influence of spine surgeons' clinical experience on fracture classification, stability assessment, and decision on management based on this classification has not been studied. Furthermore, the usefulness of varying imaging modalities including radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) in the decision process was also studied. Forty-one spine surgeons from different regions, acquainted with the AOSpine classification system, were provided with 30 thoracolumbar fractures in a 3-step assessment: first radiographs, followed by CT and MRI. Surgeons classified the fracture, evaluated stability, chose management, and identified reasons for any changes. The surgeons were divided into 2 groups based on years of clinical experience as <10 years (n = 12) and >10 years (n = 29). There were no significant differences between the 2 groups in correctly classifying A1, B2, and C type fractures. Surgeons with less experience had more correct diagnosis in classifying A3 (47.2% vs 38.5% in step 1, 73.6% vs 60.3% in step 2 and 77.8% vs 65.5% in step 3), A4 (16.7% vs 24.1% in step 1, 72.9% vs 57.8% in step 2 and 70.8% vs 56.0% in step3) and B1 injuries (31.9% vs 20.7% in step 1, 41.7% vs 36.8% in step 2 and 38.9% vs 33.9% in step 3). In the assessment of fracture stability and decision on treatment, the less and more experienced surgeons performed equally. The selection of a particular treatment plan varied in all subtypes except in A1 and C type injuries. Surgeons' experience did not significantly affect overall fracture classification, evaluating stability and planning the treatment. Surgeons with less experience had a higher percentage of correct classification in A3 and A4 injuries. Despite variations between them in classification, the assessment of overall stability and management decisions were similar between the 2 groups.
Sjöberg, Christina; Wallerstedt, Susanna M
2013-09-01
To investigate whether medication reviews increase treatment with fracture-preventing drugs and decrease treatment with fall-risk-increasing drugs. Randomized controlled trial (1:1). Departments of orthopedics, geriatrics, and medicine at Sahlgrenska University Hospital, Gothenburg, Sweden. One hundred ninety-nine consecutive individuals with hip fracture aged 65 and older. Medication reviews, based on assessments of risks of falls and fractures, regarding fracture-preventing and fall-risk-increasing drugs, performed by a physician, conveyed orally and in written form to hospital physicians during the hospital stay, and to general practitioners after discharge. Primary outcomes were changes in treatment with fracture-preventing and fall-risk-increasing drugs 12 months after discharge. Secondary outcomes were falls, fractures, deaths, and physicians' attitudes toward the intervention. At admission, 26% of intervention and 29% of control participants were taking fracture-preventing drugs, and 12% and 11%, respectively, were taking bone-active drugs, predominantly bisphosphonates. After 12 months, 77% of intervention and 58% of control participants were taking fracture-preventing drugs (P = .01), and 29% and 15%, respectively, were taking bone-active drugs (P = .04). Mean number of fall-risk-increasing drugs per participants was 3.1 (intervention) and 3.1 (control) at admission and 2.9 (intervention) and 3.1 (control) at 12 months (P = .62). No significant differences in hard endpoints were found. The responding physicians (n = 65) appreciated the intervention; on a scale from 1 (very bad) to 6 (very good), the median rating was 5 (interquartile range (IQR) 4-6) for the oral part and 5 (IQR 4-5.5) for the text part. Medication reviews performed and conveyed by a physician increased treatment with fracture-preventing drugs but did not significantly decrease treatment with fall-risk-increasing drugs in older adults with hip fracture. Prescribing physicians appreciated this intervention. © 2013, Copyright the Authors Journal compilation © 2013, The American Geriatrics Society.
NASA Astrophysics Data System (ADS)
Earnest, E. J.; Boutt, D. F.; Murdoch, L.; Hisz, D. B.; Ebenhack, J.; Kieft, T. L.; Onstott, T. C.; Wang, H. F.
2011-12-01
Mine-based ecohydrology studies provide unique access to deep flow systems at multiple crustal depths. Mass and energy transfer in such deep flow systems is typically dominated by localized flow through discrete features such as fractures and faults, of which only a small percentage contribute to both local and regional flow systems. Predicting which fractures are contributing to flow and transport in these networks has proven extremely difficult. Researchers working at deeper crustal levels (Barton et al., 1995) have successfully predicted fracture network permeability using relationships between fracture aperture (i.e. transmissivity) and in-situ stress. Observations suggest that compared to porous media, fractured rocks have flow systems that operate across large spatial scales and may contain clusters that are hydraulically isolated. . This point is important as these flow systems can house fluids and microbes in isolated clusters and are minimally impacted by the presence of a mine. One example of this is the the former Homestake gold mine in the northern Black Hills, South Dakota, which is being considered as a location for an underground science laboratory. Mine workings cover several km2 in plan and extend to a depth 2.4 km. The area is dominantly Proterozoic metamorphic rocks, forming regional-scale folds with plunge axes oriented ~40o to the SSE. Prior analysis of the hydrogeology of the area indicates that permeability is strongly dependent on effective stress; an increase in permeability with decreasing depth appears to be an important factor controlling the development of a shallow ground water flow systems. In this contribution we examine a set of factors contributing to permeability distribution at the site with a specific focus on: 1) refining permeability-depth models for fractured rock to include the influence of both normal and shear fracture deformation on permeability-depth trends, 2) promote the development and testing of a stress-path fracture permeability hypothesis to examine space-time fracture permeability evolution at various depths, and 3) evaluate factors necessary to create and sustain isolated fracture clusters that could be targets for studies of ecohydrology. Preliminary field work in fractured rocks of Eastern Massachusetts suggest that the stress-path hypothesis, in which fracture permeability undergoes spatial and temporal changes due to erosion and rotatation of the in situ stress field, can be used to explain depth-dependent permeability trends, and is particularly significant for flow systems at depths significant for deep ecohydrology studies.
Rib fractures in trauma patients: does operative fixation improve outcome?
Majak, Peter; Næss, Pål A
2016-12-01
Renewed interest in surgical fixation of rib fractures has emerged. However, conservative treatment is still preferred at most surgical departments. We wanted to evaluate whether operative treatment of rib fractures may benefit severely injured patients. Several studies report a reduction in mechanical ventilation time, ICU length of stay (LOS), hospital LOS, pneumonia, need for tracheostomy, pain and costs in operatively treated patients with multiple rib fractures compared with patients treated nonoperatively. Although patient selection and timing of the operation seem crucial for successful outcome, no consensus exists. Mortality reduction has only been shown in a few studies. Most studies are retrospective cohort and case-control studies. Only four randomized control trials exist. Conservative treatment, consisting of respiratory assistance and pain control, is still the treatment of choice in the vast majority of patients with multiple rib fractures. In selected patients, operative fixation of fractured ribs within 72 h postinjury may lead to better outcome. More randomized control trials are needed to further determine who benefits from surgical fixation of rib fractures.
Fractures in sport: Optimising their management and outcome
Robertson, Greg AJ; Wood, Alexander M
2015-01-01
Fractures in sport are a specialised cohort of fracture injuries, occurring in a high functioning population, in which the goals are rapid restoration of function and return to play with the minimal symptom profile possible. While the general principles of fracture management, namely accurate fracture reduction, appropriate immobilisation and timely rehabilitation, guide the treatment of these injuries, management of fractures in athletic populations can differ significantly from those in the general population, due to the need to facilitate a rapid return to high demand activities. However, despite fractures comprising up to 10% of all of sporting injuries, dedicated research into the management and outcome of sport-related fractures is limited. In order to assess the optimal methods of treating such injuries, and so allow optimisation of their outcome, the evidence for the management of each specific sport-related fracture type requires assessment and analysis. We present and review the current evidence directing management of fractures in athletes with an aim to promote valid innovative methods and optimise the outcome of such injuries. From this, key recommendations are provided for the management of the common fracture types seen in the athlete. Six case reports are also presented to illustrate the management planning and application of sport-focussed fracture management in the clinical setting. PMID:26716081
Displaced mid-shaft clavicular fractures: is conservative treatment still preferred?
Brin, Yaron S; Palmanovich, Ezequiel; Dolev, Eran; Nyska, Meir; Kish, Benyamin J
2014-12-01
A clavicular fracture accounts for 2.6%-5% of adult fractures. Fractures in the middle-third (OTA 15-B) represent 69%-82% of all clavicular fractures. There is no consensus among orthopedic surgeons regarding treatment for these fractures: many support conservative treatment even for displaced middle-third clavicular fractures, while others choose operative treatment. To assess the attitudes of orthopedic surgeons regarding treatment of displaced mid-shaft clavicular fractures. We conducted a survey in which we interviewed orthopedic surgeons from various countries during the 2012 EFORT meeting in Berlin. The questionnaire included an X-ray of a displaced middle-third clavicular fracture, as well as questions regarding the surgeon's proposed treatment plan. A total of 177 orthopedic surgeons completed the questionnaire; 49% preferred operative treatment for a displaced middle-third clavicular fracture. Among the orthopedic trauma specialists, 58% suggested operative treatment, as did 82% of shoulder specialists. Most surgeons preferred a locking plate for fixation. The treatment approach for a displaced middle-third clavicular fracture seems to be evenly split between conservative and operative approaches. The tendency toward operative treatment was.even more remarkable among orthopedic trauma specialists and shoulder specialists who completed the questionnaire. Most surgeons prefer a locking plate as a fixation system for this type of fracture.
Hanusch, B C; Tuck, S P; McNally, R J Q; Wu, J J; Prediger, M; Walker, J; Tang, J; Piec, I; Fraser, W D; Datta, H K; Francis, R M
2017-10-01
The pathogenesis of low trauma wrist fractures in men is not fully understood. This study found that these men have lower bone mineral density at the forearm itself, as well as the hip and spine, and has shown that forearm bone mineral density is the best predictor of wrist fracture. Men with distal forearm fractures have reduced bone density at the lumbar spine and hip sites, an increased risk of osteoporosis and a higher incidence of further fractures. The aim of this case-control study was to investigate whether or not there is a regional loss of bone mineral density (BMD) at the forearm between men with and without distal forearm fractures. Sixty-one men with low trauma distal forearm fracture and 59 age-matched bone healthy control subjects were recruited. All subjects underwent a DXA scan of forearm, hip and spine, biochemical investigations, health questionnaires, SF-36v2 and Fracture Risk Assessment Tool (FRAX). The non-fractured arm was investigated in subjects with fracture and both forearms in control subjects. BMD was significantly lower at the ultradistal forearm in men with fracture compared to control subjects, in both the dominant (mean (SD) 0.386 g/cm 2 (0.049) versus 0.436 g/cm 2 (0.054), p < 0.001) and non-dominant arm (mean (SD) 0.387 g/cm 2 (0.060) versus 0.432 g/cm 2 (0.061), p = 0.001). Fracture subjects also had a significantly lower BMD at hip and spine sites compared with control subjects. Logistic regression analysis showed that the best predictor of forearm fracture was ultradistal forearm BMD (OR = 0.871 (0.805-0.943), p = 0.001), with the likelihood of fracture decreasing by 12.9% for every 0.01 g/cm 2 increase in ultradistal forearm BMD. Men with low trauma distal forearm fracture have significantly lower regional BMD at the ultradistal forearm, which contributes to an increased forearm fracture risk. They also have generalised reduction in BMD, so that low trauma forearm fractures in men should be considered as indicator fractures for osteoporosis.
Content-based image retrieval from a database of fracture images
NASA Astrophysics Data System (ADS)
Müller, Henning; Do Hoang, Phuong Anh; Depeursinge, Adrien; Hoffmeyer, Pierre; Stern, Richard; Lovis, Christian; Geissbuhler, Antoine
2007-03-01
This article describes the use of a medical image retrieval system on a database of 16'000 fractures, selected from surgical routine over several years. Image retrieval has been a very active domain of research for several years. It was frequently proposed for the medical domain, but only few running systems were ever tested in clinical routine. For the planning of surgical interventions after fractures, x-ray images play an important role. The fractures are classified according to exact fracture location, plus whether and to which degree the fracture is damaging articulations to see how complicated a reparation will be. Several classification systems for fractures exist and the classification plus the experience of the surgeon lead in the end to the choice of surgical technique (screw, metal plate, ...). This choice is strongly influenced by the experience and knowledge of the surgeons with respect to a certain technique. Goal of this article is to describe a prototype that supplies similar cases to an example to help treatment planning and find the most appropriate technique for a surgical intervention. Our database contains over 16'000 fracture images before and after a surgical intervention. We use an image retrieval system (GNU Image Finding Tool, GIFT) to find cases/images similar to an example case currently under observation. Problems encountered are varying illumination of images as well as strong anatomic differences between patients. Regions of interest are usually small and the retrieval system needs to focus on this region. Results show that GIFT is capable of supplying similar cases, particularly when using relevance feedback, on such a large database. Usual image retrieval is based on a single image as search target but for this application we have to select images by case as similar cases need to be found and not images. A few false positive cases often remain in the results but they can be sorted out quickly by the surgeons. Image retrieval can well be used for the planning of operations by supplying similar cases. A variety of challenges has been identified and partly solved (varying luminosity, small region of interested, case-based instead of image-based). This article mainly presents a case study to identify potential benefits and problems. Several steps for improving the system have been identified as well and will be described at the end of the paper.
Siletz, Anaar; Childers, Christopher P; Faltermeier, Claire; Singer, Emily S; Hu, Q Lina; Ko, Clifford Y; Kates, Stephen L; Maggard-Gibbons, Melinda; Wick, Elizabeth
2018-01-01
Enhanced recovery pathways (ERPs) have been shown to improve patient outcomes in a variety of contexts. This review summarizes the evidence and defines a protocol for perioperative care of patients with hip fracture and was conducted for the Agency for Healthcare Research and Quality safety program for improving surgical care and recovery. Perioperative care was divided into components or "bins." For each bin, a semisystematic review of the literature was conducted using MEDLINE with priority given to systematic reviews, meta-analyses, and randomized controlled trials. Observational studies were included when higher levels of evidence were not available. Existing guidelines for perioperative care were also incorporated. For convenience, the components of care that are under the auspices of anesthesia providers will be reported separately. Recommendations for an evidence-based protocol were synthesized based on review of this evidence. Eleven bins were identified. Preoperative risk factor bins included nutrition, diabetes mellitus, tobacco use, and anemia. Perioperative management bins included thromboprophylaxis, timing of surgery, fluid management, drain placement, early mobilization, early alimentation, and discharge criteria/planning. This review provides the evidence basis for an ERP for perioperative care of patients with hip fracture.
The use of 3D-printed titanium mesh tray in treating complex comminuted mandibular fractures
Ma, Junli; Ma, Limin; Wang, Zhifa; Zhu, Xiongjie; Wang, Weijian
2017-01-01
Abstract Rationale: Precise bony reduction and reconstruction of optimal contour in treating comminuted mandibular fractures is very difficult using traditional techniques and devices. The aim of this report is to introduce our experiences in using virtual surgery and three-dimensional (3D) printing technique in treating this clinical challenge. Patient concerns: A 26-year-old man presented with severe trauma in the maxillofacial area due to fall from height. Diagnosis: Computed tomography images revealed middle face fractures and comminuted mandibular fracture including bilateral condyles. Interventions and outcomes: The computed tomography data was used to construct the 3D cranio-maxillofacial models; then the displaced bone fragments were virtually reduced. On the basis of the finalized model, a customized titanium mesh tray was designed and fabricated using selective laser melting technology. During the surgery, a submandibular approach was adopted to repair the mandibular fracture. The reduction and fixation were performed according to preoperative plan, the bone defects in the mental area were reconstructed with iliac bone graft. The 3D-printed mesh tray served as an intraoperative template and carrier of bone graft. The healing process was uneventful, and the patient was satisfied with the mandible contour. Lessons: Virtual surgical planning combined with 3D printing technology enables surgeon to visualize the reduction process preoperatively and guide intraoperative reduction, making the reduction less time consuming and more precise. 3D-printed titanium mesh tray can provide more satisfactory esthetic outcomes in treating complex comminuted mandibular fractures. PMID:28682875
Tewari, Deepshikha; Khan, Mohd Parvez; Sagar, Nitin; China, Shyamsundar P; Singh, Atul K; Kheruka, Subhash C; Barai, Sukanta; Tewari, Mahesh C; Nagar, Geet K; Vishwakarma, Achchhe L; Ogechukwu, Omeje E; Bellare, Jayesh R; Gambhir, Sanjay; Chattopadhyay, Naibedya
2015-04-01
We investigated deleterious changes that take place in mesenchymal stem cells (MSC) and its fracture healing competence in ovariectomy (Ovx)-induced osteopenia. MSC from bone marrow (BM) of ovary intact (control) and Ovx rats was isolated. (99m)Tc-HMPAO (Technitium hexamethylpropylene amine oxime) labeled MSC was systemically transplanted to rats and fracture tropism assessed by SPECT/CT. PKH26 labeled MSC (PKH26-MSC) was bound in scaffold and applied to fracture site (drill-hole in femur metaphysis). Osteoinduction was quantified by calcein binding and microcomputed tomography. Estrogen receptor (ER) antagonist, fulvestrant was used to determine ER dependence of osteo-induction by MSC. BM-MSC number was strikingly reduced and doubling time increased in Ovx rats compared to control. SPECT/CT showed reduced localization of (99m)Tc-HMPAO labeled MSC to the fracture site, 3 h post-transplantation in Ovx rats as compared with controls. Post-transplantation, Ovx MSC labeled with PKH26 (Ovx PKH26-MSC) localized less to fracture site than control PKH26-MSC. Transplantation of either control or Ovx MSC enhanced calcein binding and bone volume at the callus of control rats over placebo group however Ovx MSC had lower efficacy than control MSC. Fulvestrant blocked osteoinduction by control MSC. When scaffold bound MSC was applied to fracture, osteoinduction by Ovx PKH26-MSC was less than control PKH26-MSC. In Ovx rats, control MSC/E2 treatment but not Ovx MSC showed osteoinduction. Regenerated bone was irregularly deposited in Ovx MSC group. In conclusion, Ovx is associated with diminished BM-MSC number and its growth, and Ovx MSC displays impaired engraftment to fracture and osteoinduction besides disordered bone regeneration.
Halpern, Rachel; Becker, Laura; Iqbal, Sheikh Usman; Kazis, Lewis E; Macarios, David; Badamgarav, Enkhjargal
2011-01-01
Osteoporosis affects approximately 10 million people in the United States and is associated with increased fracture risk and fracture-related costs. Poor adherence to osteoporosis medications is associated with higher general burden of illness compared with optimal adherence. To examine the associations of adherence to osteoporosis therapies with (a) occurrence of closed fracture, (b) all-cause medical costs, and (c) all-cause hospitalizations. This retrospective analysis of administrative claims data examined women with osteoporosis initiating therapy with alendronate, risedronate, ibandronate, or raloxifene from July 1, 2002, to March 10, 2006. Data were from a large, geographically diverse U.S. health plan that covered about 12.6 million females during the identification period. Commercially insured and Medicare Advantage plan enrollees were observed for 1 year before (baseline period) and 540 days after therapy initiation (follow-up period). Outcomes included closed fractures, all-cause medical costs, and all-cause hospitalizations; all outcomes were measured starting 180 days after therapy initiation through follow-up. All subjects had at least 2 pharmacy claims for any of the targeted osteoporosis medications. Adherence was measured with a medication possession ratio (MPR) and accounted for all osteoporosis treatment. High adherence was MPR of at least 0.80; low adherence was MPR less than 0.50. Covariates included baseline fracture, "early" fracture (in the first 180 days of follow-up), baseline corticosteroid or thyroid hormone use, health status indicators, and demographic characteristics. Outcome fractures were modeled with Cox survival regression with time-dependent cumulative MPR. All-cause medical costs and all-cause hospitalizations were modeled, respectively, with generalized linear model regression (gamma distribution, log link) and negative binomial regression. The sample comprised 21,655 patients--16,295 (75.2%) commercial and 5,360 (24.8%) Medicare Advantage. During the entire follow-up period, 5,406 (33.2%) and 2,253 (42.0%) of commercial and Medicare Advantage patients, respectively, had low adherence. Adherence tended to decrease over the follow-up period. The Cox regression showed that commercial plan patients with low versus high adherence had 37% higher risk of fracture (hazard ratio = 1.37, 95% CI = 1.12-1.68). Adherence was not significantly associated with fracture in the Medicare Advantage cohort. Commercial and Medicare Advantage patients with low versus high adherence had 12% (exponentiated coefficient = 1.12, 95% CI = 1.02-1.24) and 18% (exponentiated coefficient = 1.18, 95% CI = 1.04-1.35) higher all-cause medical costs during months 7 through 18 of follow-up. Commercial and Medicare Advantage patients with low versus high adherence had 59% (incidence rate ratio [IRR] = 1.59, 95% CI = 1.38-1.83) and 34% (IRR = 1.34, 95% CI = 1.13-1.58) more all-cause hospitalizations during months 7 through 18 of follow-up, respectively. Low adherence to osteoporosis pharmacotherapy was associated with higher risk of fracture for commercially insured but not Medicare Advantage patients and with higher all-cause medical costs and more all-cause hospitalizations in both groups. These results are consistent with the literature and highlight the importance of promoting better adherence among patients with osteoporosis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wright, C.A.; Conant, R.A.; Golich, G.M.
1995-12-31
This paper summarizes the (preliminary) findings from extensive field studies of hydraulic fracture orientation in diatomite waterfloods and related efforts to monitor the induced surface subsidence. Included are case studies from the Belridge and Lost Hills diatomite reservoirs. The primary purpose of the paper is to document a large volume of tiltmeter hydraulic fracture orientation data that demonstrates waterflood-induced fracture reorientation--a phenomenon not previously considered in waterflood development planning. Also included is a brief overview of three possible mechanisms for the observed waterflood fracture reorientation. A discussion section details efforts to isolate the operative mechanism(s) from the most extensive casemore » study, as well as suggesting a possible strategy for detecting and possibly mitigating some of the adverse effects of production/injection induced reservoir stress changes--reservoir compaction and surface subsidence as well as fracture reorientation.« less
Development of stimulation diagnostic technology. Annual report, May 1990--December 1991
DOE Office of Scientific and Technical Information (OSTI.GOV)
Warpinski, N.R.; Lorenz, J.C.
The objective of this project is to apply Sandia`s expertise and technology towards the development of stimulation diagnostic technology in the areas of in situ stress, natural fracturing, stimulation processes and instrumentation systems. Initial work has concentrated on experiment planning for a site where hydraulic fracturing could be evaluated and design models and fracture diagnostics could be validated and improved. Important issues have been defined and new diagnostics, such as inclinometers, identified. In the area of in situ stress, circumferential velocity analysis is proving to be a useful diagnostic for stress orientation. Natural fracture studies of the Frontier formation aremore » progressing; two fracture sets have been found and their relation to tectonic events have been hypothesized. Analyses of stimulation data have been performed for several sites, primarily for in situ stress information. Some new ideas in stimulation diagnostics have been proposed; these ideas may significantly improve fracture diagnostic capabilities.« less
Development of stimulation diagnostic technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Warpinski, N.R.; Lorenz, J.C.
The objective of this project is to apply Sandia's expertise and technology towards the development of stimulation diagnostic technology in the areas of in situ stress, natural fracturing, stimulation processes and instrumentation systems. Initial work has concentrated on experiment planning for a site where hydraulic fracturing could be evaluated and design models and fracture diagnostics could be validated and improved. Important issues have been defined and new diagnostics, such as inclinometers, identified. In the area of in situ stress, circumferential velocity analysis is proving to be a useful diagnostic for stress orientation. Natural fracture studies of the Frontier formation aremore » progressing; two fracture sets have been found and their relation to tectonic events have been hypothesized. Analyses of stimulation data have been performed for several sites, primarily for in situ stress information. Some new ideas in stimulation diagnostics have been proposed; these ideas may significantly improve fracture diagnostic capabilities.« less
Esmaeilzadeh, Sina; Cesme, Fatih; Oral, Aydan; Yaliman, Ayse; Sindel, Dilsad
2016-08-01
Dual-energy X-ray absorptiometry (DXA) is considered the "gold standard" in predicting osteoporotic fractures. Calcaneal quantitative ultrasound (QUS) variables are also known to predict fractures. Fracture risk assessment tools may also guide us for the detection of individuals at high risk for fractures. The aim of this case-control study was to evaluate the utility of DXA bone mineral density (BMD), calcaneal QUS parameters, FRAX® (Fracture Risk Assessment Tool), and Osteoporosis Risk Assessment Instrument (ORAI) for the discrimination of women with distal forearm or hip fractures. This case-control study included 20 women with a distal forearm fracture and 18 women with a hip fracture as cases and 76 age-matched women served as controls. BMD at the spine, proximal femur, and radius was measured using DXA and acoustic parameters of bone were obtained using a calcaneal QUS device. FRAX® 10-year probability of fracture and ORAI scores were also calculated in all participants. Receiver operating characteristic (ROC) analysis was used to assess fracture discriminatory power of all the tools. While all DXA BMD, and QUS variables and FRAX® fracture probabilities demonstrated significant areas under the ROC curves for the discrimination of hip-fractured women and those without, only 33% radius BMD, broadband ultrasound attenuation (BUA), and FRAX® major osteoporotic fracture probability calculated without BMD showed significant discriminatory power for distal forearm fractures. It can be concluded that QUS variables, particularly BUA, and FRAX® major osteoporotic fracture probability without BMD are good candidates for the identification of both hip and distal forearm fractures.
Mydriasis during Orbital Floor Fracture Reconstruction: A Novel Diagnostic and Treatment Algorithm
Yeo, Matthew S.; Al-Mousa, Radwan; Sundar, Gangadhara; Lim, Thiam Chye
2010-01-01
Orbital floor fractures are the most commonly encountered traumatic fractures in the facial skeleton. Mydriasis that is detected during orbital floor fracture reconstruction may cause significant distress to surgeons, as it may be associated with sinister events such as visual loss. It is not an uncommon problem; previous studies have shown the incidence of mydriasis to be 2.1%. The combination of careful preoperative evaluation and planning, as well as specific intraoperative investigations when mydriasis is encountered, can be immensely valuable in allaying surgeons' anxiety during orbital floor fracture reconstruction. In this review article, the authors discuss the common causes of mydriasis and present a novel systematic approach to its diagnostic evaluation devised by our unit that has been successfully implemented since 2008. PMID:22132259
DOE Office of Scientific and Technical Information (OSTI.GOV)
Advani, S.H.; Lee, T.S.; Moon, H.
1992-10-01
The analysis of pertinent energy components or affiliated characteristic times for hydraulic stimulation processes serves as an effective tool for fracture configuration designs optimization, and control. This evaluation, in conjunction with parametric sensitivity studies, provides a rational base for quantifying dominant process mechanisms and the roles of specified reservoir properties relative to controllable hydraulic fracture variables for a wide spectrum of treatment scenarios. Results are detailed for the following multi-task effort: (a) Application of characteristic time concept and parametric sensitivity studies for specialized fracture geometries (rectangular, penny-shaped, elliptical) and three-layered elliptic crack models (in situ stress, elastic moduli, and fracturemore » toughness contrasts). (b) Incorporation of leak-off effects for models investigated in (a). (c) Simulation of generalized hydraulic fracture models and investigation of the role of controllable vaxiables and uncontrollable system properties. (d) Development of guidelines for hydraulic fracture design and optimization.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Advani, S.H.; Lee, T.S.; Moon, H.
1992-10-01
The analysis of pertinent energy components or affiliated characteristic times for hydraulic stimulation processes serves as an effective tool for fracture configuration designs optimization, and control. This evaluation, in conjunction with parametric sensitivity studies, provides a rational base for quantifying dominant process mechanisms and the roles of specified reservoir properties relative to controllable hydraulic fracture variables for a wide spectrum of treatment scenarios. Results are detailed for the following multi-task effort: (a) Application of characteristic time concept and parametric sensitivity studies for specialized fracture geometries (rectangular, penny-shaped, elliptical) and three-layered elliptic crack models (in situ stress, elastic moduli, and fracturemore » toughness contrasts). (b) Incorporation of leak-off effects for models investigated in (a). (c) Simulation of generalized hydraulic fracture models and investigation of the role of controllable vaxiables and uncontrollable system properties. (d) Development of guidelines for hydraulic fracture design and optimization.« less
NASA Astrophysics Data System (ADS)
Ibrahim, Mohamed I. M.; Hariri, Mustafa M.; Abdullatif, Osman M.; Makkawi, Mohammad H.; Elzain, Hussam
2017-09-01
The basal Qusaiba hot shale member of Qalibah Formation is considered to be an important source rock in the Paleozoic petroleum system of Saudi Arabia and an exploration target for tight shale as one of the Unconventional resources of petroleum. This work has been carried out to understand the fractures network of Qusaiba shale member in outcrops located to the west of Qusayba' village in Al-Qasim area, Central Saudi Arabia. The main objective of this study is to understand the distribution of natural fractures over different lithological units. Description data sheets were used for the detailed lithological description of Qusaiba shale member on two outcrops. Spot-7 and Landsat ETM+ satellite images were used for lineament mapping and analyses on a regional scale in a GIS environment. Fractures characterization in outcrop-scale was conducted by using linear scanline method. Qusaiba shale member in the study area consists of 5 main lithofacies, divided based on their sedimentary structures and petrographical properties, from base to top in the outcrops, the lithofacies are; fissile shale, very fine-grained micaceous siltstone, bioturbated mudstone, very fine to fine-grained hummocky cross-stratified sandstone, and fine to medium-grained low/high angle cross-stratified sandstone lithofacies. Lineaments interpretation of the Spot-7 and Landsat ETM+ satellite images showed two major directions in the study area; 320° that could be related to Najd fault system and 20° that could be related to the extensional activities which took place after Amar collision. Fractures are much denser in the fissile shale and mudstone lithofacies than sandstones lithofacies, and average spacing is smaller in the fissile shale and mudstone lithofacies than sandstones lithofacies. Lineaments and large-scale fractures are Non-Stratabound fractures and they deal with the area as one big mechanical unit, but small-scale fractures are Stratabound fractures that propose different mechanical units within Qusaiba shale member in the study area. The fractures network in the study area has a wide range of properties related to fractures density, length, spacing, height, and termination degree. The conceptual multi-scale model divides the fractures in the study area into 4 orders depending on the available data that have been observed from satellite images and field. The multi-scale fractures model that was generated in this study could help to understand the distribution of stratigraphically controlled fractures when integrated with flow simulation models. Overall, this work could have a significant contribution to tight shale exploration plans in the subsurface by providing some knowledge about the fractures mechanical behavior of the lower part of Qusaiba shale member of Qalibah Formation.
NASA Astrophysics Data System (ADS)
Davy, P.; Darcel, C.; Le Goc, R.; Bour, O.
2011-12-01
We discuss the parameters that control fracture density on the Earth. We argue that most of fracture systems are spatially organized according to two main regimes. The smallest fractures can grow independently of each others, defining a "dilute" regime controlled by nuclei occurrence rate and individual fracture growth law. Above a certain length, fractures stop growing due to mechanical interactions between fractures. For this "dense" regime, we derive the fracture density distribution by acknowledging that, statistically, fractures do not cross a larger one. This very crude rule, which expresses the inhibiting role of large fractures against smaller ones but not the reverse, actually appears be a very strong control on the eventual fracture density distribution since it results in a self-similar distribution whose exponents and density term are fully determined by the fractal dimension D and a dimensionless parameter γ that encompasses the details of fracture correlations and orientations. The range of values for D and γ appears to be extremely limited, which makes this model quite universal. This theory is supported by quantitative data on either fault or joint networks. The transition between the dilute and dense regimes occurs at about a few tenths of kilometers for faults systems, and a few meters for joints. This remarkable difference between both processes is likely due to a large-scale control (localization) of the fracture growth for faulting that does not exist for jointing. Finally, we discuss the consequences of this model on both flow and mechanical properties. In the dense regime, networks appears to be very close to a critical state.
[Is Mapuche ethnicity a risk factor for hip fracture in aged?].
Sapunar, Jorge; Bravo, Paulina; Schneider, Hermann; Jiménez, Marcela
2003-10-01
Ethnic factors are involved in the risk for osteoporosis and hip fracture. To assess the effect of Mapuche ethnicity on the risk of hip fracture. A case control study. Cases were subjects over 55 years of age admitted, during one year, for hip fracture not associated to major trauma or tumors. Controls were randomly chosen from other hospital services and paired for age with cases. The magnitude of the association between ethnicity and hip fracture was expressed as odds ratio in a logistic regression model. In the study period, 156 cases with hip fracture were admitted. The proportion of subjects with Mapuche origin was significantly lower among cases than controls (11.8 and 26.5% respectively, p < 0.001). In the logistic regression model, Mapuche ethnicity was associated with hip fracture with an odds radio of 0.14 (p = 0.03, 95% CI 0.03-0.8). In this sample, Mapuche ethnicity is a protective factor for hip fracture.
Wang, Ching-Jen; Liu, Hao-Chen; Fu, Te-Hu
2007-02-01
High-energy long bone fractures of the lower extremity are at risk of poor fracture healing and high rate of non-union. Extracorporeal shockwave was shown effective to heal non-union of long bone fracture. However, the effect of shockwave on acute fractures is unknown. The purpose of this study was to investigate the effects of shockwave on acute high-energy fractures of the lower extremity. Between January and October 2004, 56 patients with 59 acute high-energy fractures were enrolled in this study. Patients were randomly divided into two groups with 28 patients with 28 fractures in the study group and 28 patients with 31 fractures in the control group. Both groups showed similar age, gender, type of fracture and follow-up time. Patients in the study group received open reduction and internal fixation and shockwave treatment immediately after surgery on odd-numbered days of the week, whereas, patients in the control group received open reduction and internal fixation without shockwave treatment on even-numbered days of the week. Postoperative managements were similarly performed in both groups including crutch walking with non-weight bearing on the affected limb until fracture healing shown on radiographs. The evaluation parameters included clinical assessments of pain score and weight bearing status of the affected leg and serial radiographs at 3, 6 and 12 months. The primary end-point is the rate of non-union at 12 months, and the secondary end point is the rate of fracture healing at 3, 6 and 12 months. At 12 months, the rate of non-union was 11% for the study group versus 20% for the control group (P < 0.001). Significantly, better rate of fracture healing was noted in the study group than the control group at 3, 6 and 12 months (P < 0.001). Extracorporeal shockwave is effective on promoting fracture healing and decreasing the rate of non-union in acute high-energy fractures of the lower extremity.
Eipeldauer, Stefan; Thomas, Anita; Hoechtl-Lee, Leonard; Kecht, Mathias; Binder, Harald; Koettstorfer, Julia; Gregori, Markus; Sarahrudi, Kambiz
2014-01-01
Sonic Hedgehog (SHH) is a new signalling pathway in bone repair. Evidence exist that SHH pathway plays a significant role in vasculogenesis and limb development during embryogenesis. Some in vitro and animal studies has already proven its potential for bone regeneration. However, no data on the role of SHH in the human fracture healing have been published so far. Seventy-five patients with long bone fractures were included into the study and divided in 2 groups. First group contained 69 patients with normal fracture healing. Four patients with impaired fracture healing formed the second group. 34 volunteers donated blood samples as control. Serum samples were collected over a period of 1 year following a standardized time schedule. In addition, SHH levels were measured in fracture haematoma and serum of 16 patients with bone fractures. Fracture haematoma and patients serum both contained lower SHH concentrations compared to control serum. The comparison between the patients' serum SHH level and the control serum revealed lower levels for the patients at all measurement time points. Significantly lower concentrations were observed at weeks 1 and 2 after fracture. SHH levels were slightly decreased in patients with impaired fracture healing without statistical significance. This is the first study to report local and systemic concentration of SHH in human fracture healing and SHH serum levels in healthy adults. A significant reduction of the SHH levels during the inflammatory phase of fracture healing was found. SHH concentrations in fracture haematoma and serum were lower than the concentration in control serum for the rest of the healing period. Our findings indicate that there is no relevant involvement of SHH in human fracture healing. Fracture repair process seem to reduce the SHH level in human. Further studies are definitely needed to clarify the underlying mechanisms.
Madanat, Rami; Moritz, Niko; Aro, Hannu T
2007-01-01
Physical phantom models have conventionally been used to determine the accuracy and precision of radiostereometric analysis (RSA) in various orthopaedic applications. Using a phantom model of a fracture of the distal radius it has previously been shown that RSA is a highly accurate and precise method for measuring both translation and rotation in three-dimensions (3-D). The main shortcoming of a physical phantom model is its inability to mimic complex 3-D motion. The goal of this study was to create a realistic computer model for preoperative planning of RSA studies and to test the accuracy of RSA in measuring complex movements in fractures of the distal radius using this new model. The 3-D computer model was created from a set of tomographic scans. The simulation of the radiographic imaging was performed using ray-tracing software (POV-Ray). RSA measurements were performed according to standard protocol. Using a two-part fracture model (AO/ASIF type A2), it was found that for simple movements in one axis, translations in the range of 25microm-2mm could be measured with an accuracy of +/-2microm. Rotations ranging from 16 degrees to 2 degrees could be measured with an accuracy of +/-0.015 degrees . Using a three-part fracture model the corresponding values of accuracy were found to be +/-4microm and +/-0.031 degrees for translation and rotation, respectively. For complex 3-D motion in a three-part fracture model (AO/ASIF type C1) the accuracy was +/-6microm for translation and +/-0.120 degrees for rotation. The use of 3-D computer modelling can provide a method for preoperative planning of RSA studies in complex fractures of the distal radius and in other clinical situations in which the RSA method is applicable.
Davey, Trish; Lanham-New, Susan A; Shaw, Anneliese M; Cobley, Rosalyn; Allsopp, Adrian J; Hajjawi, Mark O R; Arnett, Timothy R; Taylor, Pat; Cooper, Cyrus; Fallowfield, Joanne L
2015-04-01
Stress fracture is a common overuse injury within military training, resulting in significant economic losses to the military worldwide. Studies to date have failed to fully identify the bone density and bone structural differences between stress fractured personnel and controls due to inadequate adjustment for key confounding factors; namely age, body size and physical fitness; and poor sample size. The aim of this study was to investigate bone differences between male Royal Marine recruits who suffered a stress fracture during the 32 weeks of training and uninjured control recruits, matched for age, body weight, height and aerobic fitness. A total of 1090 recruits were followed through training and 78 recruits suffered at least one stress fracture. Bone mineral density (BMD) was measured at the lumbar spine (LS), femoral neck (FN) and whole body (WB) using Dual X-ray Absorptiometry in 62 matched pairs; tibial bone parameters were measured using peripheral Quantitative Computer Tomography in 51 matched pairs. Serum C-terminal peptide concentration was measured as a marker of bone resorption at baseline, week-15 and week-32. ANCOVA was used to determine differences between stress fractured recruits and controls. BMD at the LS, WB and FN sites was consistently lower in the stress fracture group (P<0.001). Structural differences between the stress fracture recruits and controls were evident in all slices of the tibia, with the most prominent differences seen at the 38% tibial slice. There was a negative correlation between the bone cross-sectional area and BMD at the 38% tibial slice. There was no difference in serum CTx concentration between stress fracture recruits and matched controls at any stage of training. These results show evidence of fundamental differences in bone mass and structure in stress fracture recruits, and provide useful data on bone risk factor profiles for stress fracture within a healthy military population. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.
Evolution of Friction and Permeability in a Propped Fracture under Shear
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Fengshou; Fang, Yi; Elsworth, Derek
We explore the evolution of friction and permeability of a propped fracture under shear. We examine the effects of normal stress, proppant thickness, proppant size, and fracture wall texture on the frictional and transport response of proppant packs confined between planar fracture surfaces. The proppant-absent and proppant-filled fractures show different frictional strength. For fractures with proppants, the frictional response is mainly controlled by the normal stress and proppant thickness. The depth of shearing-concurrent striations on fracture surfaces suggests that the magnitude of proppant embedment is controlled by the applied normal stress. Under high normal stress, the reduced friction implies thatmore » shear slip is more likely to occur on propped fractures in deeper reservoirs. The increase in the number of proppant layers, from monolayer to triple layers, significantly increases the friction of the propped fracture due to the interlocking of the particles and jamming. Permeability of the propped fracture is mainly controlled by the magnitude of the normal stress, the proppant thickness, and the proppant grain size. Permeability of the propped fracture decreases during shearing due to proppant particle crushing and related clogging. Proppants are prone to crushing if the shear loading evolves concurrently with the normal loading.« less
Evolution of Friction and Permeability in a Propped Fracture under Shear
Zhang, Fengshou; Fang, Yi; Elsworth, Derek; ...
2017-12-04
We explore the evolution of friction and permeability of a propped fracture under shear. We examine the effects of normal stress, proppant thickness, proppant size, and fracture wall texture on the frictional and transport response of proppant packs confined between planar fracture surfaces. The proppant-absent and proppant-filled fractures show different frictional strength. For fractures with proppants, the frictional response is mainly controlled by the normal stress and proppant thickness. The depth of shearing-concurrent striations on fracture surfaces suggests that the magnitude of proppant embedment is controlled by the applied normal stress. Under high normal stress, the reduced friction implies thatmore » shear slip is more likely to occur on propped fractures in deeper reservoirs. The increase in the number of proppant layers, from monolayer to triple layers, significantly increases the friction of the propped fracture due to the interlocking of the particles and jamming. Permeability of the propped fracture is mainly controlled by the magnitude of the normal stress, the proppant thickness, and the proppant grain size. Permeability of the propped fracture decreases during shearing due to proppant particle crushing and related clogging. Proppants are prone to crushing if the shear loading evolves concurrently with the normal loading.« less
Principles of pediatric mandibular fracture management.
Cole, Patrick; Kaufman, Yoav; Izaddoost, Shayan; Hatef, Daniel A; Hollier, Larry
2009-03-01
Mandible fractures are commonplace in today's craniofacial practice; however, managing the infrequent, operative pediatric mandible injury requires a thorough knowledge base and thoughtful approach. Not only do these patients demonstrate variable anatomy due to differing stages of dental eruption, but condylar disruption may translate into long-term growth disturbance. In addition, patient immaturity often complicates cooperation, and both fixation strategies and postoperative planning must take this into account. As a supplement to the authors' video presentation, the present article focuses on repair of the symphyseal fracture and bilateral condylar injuries in the pediatric patient.
Periprosthetic fracture of the proximal tibia after lateral unicompartmental knee arthroplasty.
Kumar, Arun; Chambers, Iain; Wong, Paul
2008-06-01
We report a case of periprosthetic fracture of the proximal tibia after lateral unicompartmental knee arthroplasty following a trivial fall. At the time of surgery, the components were found to be loose; and there was a large uncontained tibial defect with bone loss and communition at the fracture site. The patient was treated by revision total knee arthroplasty and proximal structural tibial allograft, with a satisfactory result at 5-year follow up. Our case illustrates that a bone-conserving unicompartmental knee arthroplasty, if complicated by a periprosthetic fracture, can also present with a difficult surgical problem. Attention to preoperative planning and to availability of structural allograft for such difficult cases is recommended.
NASA Astrophysics Data System (ADS)
Bisdom, Kevin; Bertotti, Giovanni; Nick, Hamidreza M.
2016-10-01
Aperture has a controlling impact on porosity and permeability and is a source of uncertainty in modeling of naturally fractured reservoirs. This uncertainty results from difficulties in accurately quantifying aperture in the subsurface and from a limited fundamental understanding of the mechanical and diagenetic processes that control aperture. In the absence of cement bridges and high pore pressure, fractures in the subsurface are generally considered to be closed. However, experimental work, outcrop analyses and subsurface data show that some fractures remain open, and that aperture varies even along a single fracture. However, most fracture flow models consider constant apertures for fractures. We create a stress-dependent heterogeneous aperture by combining Finite Element modeling of discrete fracture networks with an empirical aperture model. Using a modeling approach that considers fractures explicitly, we quantify equivalent permeability, i.e. combined matrix and stress-dependent fracture flow. Fracture networks extracted from a large outcropping pavement form the basis of these models. The results show that the angle between fracture strike and σ1 has a controlling impact on aperture and permeability, where hydraulic opening is maximum for an angle of 15°. At this angle, the fracture experiences a minor amount of shear displacement that allows the fracture to remain open even when fluid pressure is lower than the local normal stress. Averaging the heterogeneous aperture to scale up permeability probably results in an underestimation of flow, indicating the need to incorporate full aperture distributions rather than simplified aperture models in reservoir-scale flow models.
Im, So-Min; Huh, Yoon-Hyuk; Cho, Lee-Ra; Park, Chan-Jin
2017-02-01
The aim of this study was to investigate the effect of reinforcing materials on the fracture resistances of glass fiber mesh- and Cr-Co metal mesh-reinforced maxillary complete dentures under fatigue loading. Glass fiber mesh- and Cr-Co mesh-reinforced maxillary complete dentures were fabricated using silicone molds and acrylic resin. A control group was prepared with no reinforcement (n = 15 per group). After fatigue loading was applied using a chewing simulator, fracture resistance was measured by a universal testing machine. The fracture patterns were analyzed and the fractured surfaces were observed by scanning electron microscopy. After cyclic loading, none of the dentures showed cracks or fractures. During fracture resistance testing, all unreinforced dentures experienced complete fracture. The mesh-reinforced dentures primarily showed posterior framework fracture. Deformation of the all-metal framework caused the metal mesh-reinforced denture to exhibit the highest fracture resistance, followed by the glass fiber mesh-reinforced denture ( P <.05) and the control group ( P <.05). The glass fiber mesh-reinforced denture primarily maintained its original shape with unbroken fibers. River line pattern of the control group, dimples and interdendritic fractures of the metal mesh group, and radial fracture lines of the glass fiber group were observed on the fractured surfaces. The glass fiber mesh-reinforced denture exhibits a fracture resistance higher than that of the unreinforced denture, but lower than that of the metal mesh-reinforced denture because of the deformation of the metal mesh. The glass fiber mesh-reinforced denture maintains its shape even after fracture, indicating the possibility of easier repair.
Vaile, J H; Sullivan, L; Connor, D; Bleasel, J F
2013-10-01
Our fracture liaison service identifies patients with low trauma fractures, determines the need for osteoporosis therapy and instigates therapy if necessary. We describe the tracking and outcome of 768 patients attending our emergency department over 1 year and discuss the problems we encountered and potential solutions. Osteoporotic fractures result in substantial morbidity, mortality and economic cost, and patients sustaining a first fracture are known to be at higher risk of sustaining future fracture. Treatment of at-risk patients has been shown to assist in prevention of future fracture including hip fracture. We established a "First Fracture Project" to identify and treat these patients in 2003. We assessed "A Year of Fractures": the logistics, outcome and problems in tracking patients presenting to our emergency department with a low trauma fracture by our fracture liaison service, over 1 year from July 2008 to June 2009. Patients were tracked by our osteoporosis nurse and offered assessment, and treatment where necessary. In 1 year, 768 patients aged 50 or over were identified from emergency department records as attending with a low trauma fracture. About 84 % of patients eventually received assessment. Of the162 patients progressing through the entire process, 74 % had osteoporosis treatment planned and/or commenced. Our fracture liaison service was effective at identifying most low trauma fracture patients at risk of further fracture and providing access to osteoporosis assessment. There were many difficulties: we outline logistic and practical issues in delivering our service and suggest potential improvements.
NASA Astrophysics Data System (ADS)
Ukar, Estibalitz; Eichhubl, Peter; Fall, Andras; Hooker, John
2013-04-01
In tight gas reservoirs, understanding the characteristics, orientation and distribution of natural open fractures, and how these relate to the structural and stratigraphic setting are important for exploration and production. Outcrops provide the opportunity to sample fracture characteristics that would otherwise be unknown due to the limitations of sampling by cores and well logs. However, fractures in exhumed outcrops may not be representative of fractures in the reservoir because of differences in burial and exhumation history. Appropriate outcrop analogs of producing reservoirs with comparable geologic history, structural setting, fracture networks, and diagenetic attributes are desirable but rare. The Jurassic to Lower Cretaceous Nikanassin Formation from the Alberta Foothills produces gas at commercial rates where it contains a network of open fractures. Fractures from outcrops have the same diagenetic attributes as those observed in cores <100 km away, thus offering an ideal opportunity to 1) evaluate the distribution and characteristics of opening mode fractures relative to fold cores, hinges and limbs, 2) compare the distribution and attributes of fractures in outcrop vs. core samples, 3) estimate the timing of fracture formation relative to the evolution of the fold-and-thrust belt, and 4) estimate the degradation of fracture porosity due to postkinematic cementation. Cathodoluminescence images of cemented fractures in both outcrop and core samples reveal several generations of quartz and ankerite cement that is synkinematic and postkinematic relative to fracture opening. Crack-seal textures in synkinematic quartz are ubiquitous, and well-developed cement bridges abundant. Fracture porosity may be preserved in fractures wider than ~100 microns. 1-D scanlines in outcrop and core samples indicate fractures are most abundant within small parasitic folds within larger, tight, mesoscopic folds. Fracture intensity is lower away from parasitic folds; intensity progressively decreases from the faulted cores of mesoscopic folds to their forelimbs, with lowest intensities within relatively undeformed backlimb strata. Fracture apertures locally increase adjacent to reverse faults without an overall increase in fracture frequency. Fluid inclusion analyses of crack-seal quartz cement indicate both aqueous and methane-rich inclusions are present. Homogenization temperatures of two-phase inclusions indicate synkinematic fracture cement precipitation and fracture opening under conditions at or near maximum burial of 190-210°C in core samples, and 120-160°C in outcrop samples. In comparison with the fracture evolution in other, less deformed tight-gas sandstone reservoirs such as the Piceance and East Texas basins where fracture opening is primarily controlled by gas generation, gas charge, and pore fluid pressure, these results suggest a strong control of regional tectonic processes on fracture generation. In conjunction with timing and rate of gas charge, rates of fracture cement growth, and stratigraphic-lithological controls, these processes determine the overall distribution of open fractures in these reservoirs.
NASA Astrophysics Data System (ADS)
Ukar, E.; Eichhubl, P.; Fall, A.; Hooker, J. N.
2012-12-01
In tight gas reservoirs, understanding the characteristics, orientation and distribution of natural open fractures, and how these relate to the structural and stratigraphic setting are important for exploration and production. Outcrops provide the opportunity to sample fracture characteristics that would otherwise be unknown due to the limitations of sampling by cores and well logs. However, fractures in exhumed outcrops may not be representative of fractures in the reservoir because of differences in burial and exhumation history. Appropriate outcrop analogs of producing reservoirs with comparable geologic history, structural setting, fracture networks, and diagenetic attributes are desirable but rare. The Jurassic to Lower Cretaceous Nikanassin Formation from the Alberta Foothills produces gas at commercial rates where it contains a network of open fractures. Fractures from outcrops have the same diagenetic attributes as those observed in cores <100 km away, thus offering an ideal opportunity to 1) evaluate the distribution and characteristics of opening mode fractures relative to fold cores, hinges and limbs, 2) compare the distribution and attributes of fractures in outcrop vs. core samples, 3) estimate the timing of fracture formation relative to the evolution of the fold-and-thrust belt, and 4) estimate the degradation of fracture porosity due to postkinematic cementation. Cathodoluminescence images of cemented fractures in both outcrop and core samples reveal several generations of quartz and ankerite cement that is synkinematic and postkinematic relative to fracture opening. Crack-seal textures in synkinematic quartz are ubiquitous, and well-developed cement bridges abundant. Fracture porosity may be preserved in fractures wider than ~100 microns. 1-D scanlines in outcrop and core samples indicate fractures are most abundant within small parasitic folds within larger, tight, mesoscopic folds. Fracture intensity is lower away from parasitic folds; intensity progressively decreases from the faulted cores of mesoscopic folds to their forelimbs, with lowest intensities within relatively undeformed backlimb strata. Fracture apertures locally increase adjacent to reverse faults without an overall increase in fracture frequency. Fluid inclusion analyses of crack-seal quartz cement indicate both aqueous and methane-rich inclusions are present. Homogenization temperatures of two-phase inclusions indicate synkinematic fracture cement precipitation and fracture opening under conditions at or near maximum burial of 190-210°C in core samples, and 120-160°C in outcrop samples. In comparison with the fracture evolution in other, less deformed tight-gas sandstone reservoirs such as the Piceance and East Texas basins where fracture opening is primarily controlled by gas generation, gas charge, and pore fluid pressure, these results suggest a strong control of regional tectonic processes on fracture generation. In conjunction with timing and rate of gas charge, rates of fracture cement growth, and stratigraphic-lithological controls, these processes determine the overall distribution of open fractures in these reservoirs.
Fracture epidemiology and control in a developmental center.
Lohiya, G S; Crinella, F M; Tan-Figueroa, L; Caires, S; Lohiya, S
1999-01-01
During 3.5 years, 182 fractures occurred among 994 residents of a developmental center. The fracture rate was 5.2 per 100 person-years (1.7 times greater than the rate in the US population). Fracture rate was significantly greater in residents with: epilepsy, older age, male gender, white race, independent ambulation, osteoporosis, and residence in intermediate care (versus skilled nursing) units; it was not affected by severity of mental retardation. Hand and foot bones were fractured in 58% of cases. Femur fracture occurred in 13 cases (7%). Fracture was caused by a fall in 41 cases (23%); its cause was indeterminable in 105 cases (58%). Fractures, occurring without significant injury, may be an important cause of preventable disability in this population. Control measures are suggested. Images Figure 1. Figure 2. PMID:10344173
AN INTEGRATED VIEW OF GROUNDWATER FLOW CHARACTERIZATION AND MODELING IN FRACTURED GEOLOGIC MEDIA
The particular attributes of fractured geologic media pertaining to groundwater flow characterization and modeling are presented. These cover the issues of fracture network and hydraulic control of fracture geometry parameters, major and minor fractures, heterogeneity, anisotrop...
Dovjak, Peter; Föger-Samwald, Ursula; Konrad, Maarit; Bichler, Bernhard; Pietschmann, Peter
2015-10-01
With respect to the pathogenesis of osteoporosis, primary and secondary forms of the disease can be distinguished. It has been recognized that the incidence of primary and secondary osteoporosis differs in women and men. The aim of the present study was to assess the incidence and gender distribution of factors contributing to osteoporosis in older hip fracture patients. In this cross-sectional study 404 patients with hip fractures and controls referred to an acute geriatric care department over a period of 15 months were included. The medical history was recorded and blood samples were analyzed for routine laboratory parameters. A total of 249 patients with hip fractures and 155 matched controls were studied. The Tinetti test and the Barthel index were found to show highly significant differences in both groups mainly because of the postoperative state of patients with fractures. Vitamin D deficiency was found in 94.1% of male fracture patients and 94.6% of female fracture patients. On average 2.4 secondary contributors of osteoporosis were present in male fracture patients versus 2.9 in male controls and 2.3 in female fracture patients versus 2.3 in female controls. For most parameters no significant gender differences of possible secondary contributors to osteoporosis were found. Secondary osteoporosis was diagnosed in all male fracture patients and in 56.2% of all female fracture patients. Based on the findings of this study it is recommended that hip fracture patients should be assessed for secondary contributors of osteoporosis. Although the overall distribution of secondary contributors was similar in women and men, the prevalence of secondary osteoporosis was higher in men.
Remote ballistic fractures in a gelatine model - aetiology and surgical implications
2013-01-01
Background Remote ballistic femoral fractures are rare fractures reported in the literature but still debated as to their existence and, indeed, their treatment. This study aimed to prove their existence, understand how they occur and determine which ammunition provides the greatest threat. In addition, fracture patterns, soft tissue disruption and contamination were assessed to aid in treatment planning. Method We filmed 42 deer femora embedded in ballistic gelatine and shot with four different military (5.56 × 45 mm, 7.62 × 39 mm) and civilian (9 × 19 mm, .44 in.) bullets, at varying distances off the bone (0–10 cm). Results Two remote ballistic fractures occurred, both with .44 in. hollow-point bullets shot 3 cm off the bone. These fractures occurred when the leading edge of the expanding temporary cavity impacted the femur's supracondylar region, producing a wedge-shaped fracture with an undisplaced limb, deceivingly giving the appearance of a spiral fracture. No communication was seen between the fracture and permanent cavity, despite the temporary cavity encasing the fracture and stripping periosteum from its base. Conclusion These fractures occur with civilian ammunition, but cannot prove their existence with military rounds. They result from the expanding temporary cavity affecting the weakest part of the bone, creating a potentially contaminated wedge-shaped fracture, important for surgeons considering operative intervention. PMID:23721113
Federal Aviation Administration Plan for Research, Engineering & Development, 1998.
1998-02-01
release rate. • Improved fracture toughness of non-combustible geopolymer composite fire barriers to enable use as interior and secondary composites ...Fire Resistant, Non-Toxic Interior Panels for Evaluation of Heat Release Rate ♦ Improved Fracture Toughness of Non-Combustible Geopolymer Composite ... composites , atmospheric hazards, crash worthiness, fire safety, and forensics capabilities to support accident investigations. Aviation Security R,E&D
Computerized fracture critical and specialized bridge inspection program with NDE applications
NASA Astrophysics Data System (ADS)
Fish, Philip E.
1998-03-01
Wisconsin Department of Transportation implemented a Fracture Critical & Specialized Inspection Program in 1987. The program has a strong emphasis on Nondestructive Testing (NDT). The program is also completely computerized, using laptop computers to gather field data, digital cameras for pictures, and testing equipment with download features. Final inspection reports with detailed information can be delivered within days of the inspection. The program requires an experienced inspection team and qualified personnel. Individuals performing testing must be licensed ASNT (American Society for Nondestructive Testing) Level III and must be licensed Certified Weld Inspectors (American Welding Society). Several critical steps have been developed to assure that each inspection identifies all possible deficiencies that may be possible on a Fracture Critical or Unique Bridge. They include; review of all existing plans and maintenance history; identification of fracture critical members, identification of critical connection details, welds, & fatigue prone details, development of visual and NDE inspection plan; field inspection procedures; and a detailed formal report. The program has found several bridges with critical fatigue conditions which have resulted in replacement or major rehabilitation. In addition, remote monitoring systems have been installed on structures with serious cracking to monitor for changing conditions.
NASA Astrophysics Data System (ADS)
Song, Jie; Dong, Mei; Koltuk, Serdar; Hu, Hui; Zhang, Luqing; Azzam, Rafig
2018-05-01
Construction works associated with the building of reservoirs in mountain areas can damage the stability of adjacent valley slopes. Seepage processes caused by the filling and drawdown operations of reservoirs also affect the stability of the reservoir banks over time. The presented study investigates the stability of a fractured-rock slope subjected to seepage forces in the lower basin of a planned pumped-storage hydropower (PSH) plant in Blaubeuren, Germany. The investigation uses a hydro-mechanically coupled finite-element analyses. For this purpose, an equivalent continuum model is developed by using a representative elementary volume (REV) approach. To determine the minimum required REV size, a large number of discrete fracture networks are generated using Monte Carlo simulations. These analyses give a REV size of 28 × 28 m, which is sufficient to represent the equivalent hydraulic and mechanical properties of the investigated fractured-rock mass. The hydro-mechanically coupled analyses performed using this REV size show that the reservoir operations in the examined PSH plant have negligible effect on the adjacent valley slope.
Coutinho, Evandro S F; Fletcher, Astrid; Bloch, Katia V; Rodrigues, Laura C
2008-08-26
Fracture after falling has been identified as an important problem in public health. Most studies of risk factors for fractures due to falls have been carried out in developed countries, although the size of the elderly population is increasing fast in middle income countries. The objective of this paper is to identify risk factors for fall related to severe fractures in those aged 60 or more in a middle-income country. A case-control study was carried out in Rio de Janeiro-Brazil based general hospitals between 2002-2003. Two hundred-fifty hospitalised cases of fracture were matched with 250 community controls by sex, age group and living area. Data were collected for socio-demographic variables, health status and drugs used before the fall. A conditional logistic regression model was fitted to identify variables associated with the risk of fall related severe fracture. Low body mass index, cognitive impairment, stroke and lack of urine control were associated with increased risk of severe fall related fractures. Benzodiazepines and muscle relaxants were also related to an increased risk of severe fractures while moderate use of alcohol was associated with reduced risk. Although the association between benzodiazepines and fractures due to fall has been consistently demonstrated for old people, this has not been the case for muscle relaxant drugs. The decision to prescribe muscle relaxants for elderly people should take into account the risk of severe fracture associated with these drugs.
Attractive results obtained in Mexico cementing with turbulent flow and in fracturing marginal wells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1970-02-01
The cementing with turbulent flow and the fracturing at high rates of injection have borne appreciable fruit in a gas-producing region of Mexico, known as the NE. Front District, with headquarters in Reynosa. By cementing with turbulent flow, Petroleos Mexicanos (Pemex) has increased to nearly 90% the success ratio of casing cementing. In the same general area, due to hydraulic fracturing, gas fields which before were considered marginal, have become good producers. The fracturing jobs must be well-planned and well-executed. The results in these Eocene formations show considerable variance, from good to extraordinary. The results show a low productivity ofmore » increase of 66.3% and a high productivity of 326%, following frac treatment. Graphical representations show cementing with turbulent flow; and the effect of fracturing.« less
Depressive symptoms are associated with reduced neutrophil function in hip fracture patients☆
Duggal, Niharika Arora; Upton, Jane; Phillips, Anna C.; Hampson, Peter; Lord, Janet M.
2013-01-01
Hip fracture is a common trauma in older adults with a high incidence of depression, which relates to poorer prognosis including increased risk of infection. Ageing is accompanied by reduced immunity, termed immunesenescence, resulting in increased susceptibility to infection. We examined whether physical trauma (hip fracture) and psychological distress (depressive symptoms) had additive effects upon the aged immune system that might contribute to poor outcomes after injury. Neutrophil function was assessed in 101 hip fracture patients (81 female) 6 weeks and 6 months after injury and 43 healthy age-matched controls (28 female). Thirty eight fracture patients had depressive symptoms at 6 weeks. No difference in neutrophil phagocytosis of Escherichia coli was observed between controls and hip fracture patients, but superoxide production was significantly reduced in hip fracture patients with depressive symptoms compared with patients without symptoms (p = .001) or controls (p = .004) at 6 weeks. Superoxide production improved 6 months following fracture to the level seen in controls. We detected elevated serum cortisol, reduced dehydroepiandrosterone sulphate (DHEAS) and an increased cortisol:DHEAS ratio in fracture patients with depressive symptoms compared with patients without depressive symptoms or controls at 6 weeks and 6 months after injury. Serum IL6, TNFα and IL10 were higher among patients with depressive symptoms at 6 weeks. The cortisol:DHEAS ratio and IL6 levels related to depressive symptom scores but not to neutrophil function. In conclusion, depressive symptoms related to poorer neutrophil function after hip fracture, but this was not driven by changes in stress hormone or cytokine levels. PMID:23876747
NASA Astrophysics Data System (ADS)
Zhao, Xinglong; Huang, Bingxiang; Wang, Zhen
2018-06-01
Directional rupture is a significant and routine problem for ground control in mines. Directional hydraulic fracturing controlled by dense linear multi-hole drilling was proposed. The physical model experiment, performed by the large-scale true triaxial hydraulic fracturing experimental system, aims to investigate the basic law of directional hydraulic fracturing controlled by dense linear multi-hole drilling, the impact of three different pumping modes on the initiation and propagation of hydraulic fractures among boreholes are particular investigated. The experimental results indicated that there are mutual impacts among different boreholes during crack propagation, which leads to a trend of fracture connection. Furthermore, during propagation, the fractures not only exhibit an overall bias toward the direction in which the boreholes are scattered but also partially offset against the borehole axes and intersect. The directional fracturing effect of equivalent pumping rate in each borehole is better than the other two pumping modes. In practical applications, because of rock mass heterogeneity, there may be differences in terms of filtration rate and effective input volume in different boreholes; thus, water pressure increase and rupture are not simultaneous in different boreholes. Additionally, if the crack initiation directions of different boreholes at different times are not consistent with each other, more lamellar failure planes will occur, and the mutual influences of these lamellar failure planes cause fractures to extend and intersect.
Distinct hip and rearfoot kinematics in female runners with a history of tibial stress fracture.
Milner, Clare E; Hamill, Joseph; Davis, Irene S
2010-02-01
Cross-sectional controlled laboratory study. To investigate the kinematics of the hip, knee, and rearfoot in the frontal and transverse planes in female distance runners with a history of tibial stress fracture. Tibial stress fractures are a common overuse injury in runners, accounting for up to half of all stress fractures. Abnormal kinematics of the lower extremity may contribute to abnormal musculoskeletal load distributions, leading to an increased risk of stress fractures. Thirty female runners with a history of tibial stress fracture were compared to 30 age-matched and weekly-running-distance-matched control subjects with no previous lower extremity bony injuries. Kinematic and kinetic data were collected using a motion capture system and a force platform, respectively, as subjects ran in the laboratory. Selected variables of interest were compared between the groups using a multivariate analysis of variance (MANOVA). Peak hip adduction and peak rearfoot eversion angles were greater in the stress fracture group compared to the control group. Peak knee adduction and knee internal rotation angles and all joint angles at impact peak were similar between the groups. Runners with a previous tibial stress fracture exhibited greater peak hip adduction and rearfoot eversion angles during the stance phase of running compared to healthy controls. A consequence of these mechanics may be altered load distribution within the lower extremity, predisposing individuals to stress fracture.
Fractures in Kidney Transplant Recipients: A Comparative Study Between England and New York State.
Arnold, Julia; Mytton, Jemma; Evison, Felicity; Gill, Paramjit S; Cockwell, Paul; Sharif, Adnan; Ferro, Charles J
2017-11-15
Fractures are associated with high morbidity and are a major concern for kidney transplant recipients. No comparative analysis has yet been conducted between countries in the contemporary era to inform future international prevention trials. Data were obtained from the Hospital Episode Statistics and the Statewide Planning and Research Cooperative databases on all adult kidney transplants performed in England and New York State from 2003 to 2013, respectively, and on posttransplant fracture-related hospitalization from 2003 to 2014. Our analysis included 18 493 English and 11 602 New York State kidney transplant recipients. Overall, 637 English recipients (3.4%) and 398 New York State recipients (3.4%) sustained a fracture, giving an unadjusted event rate of 7.0 and 5.9 per 1000 years, respectively (P = .948). Of these, 147 English (0.8%) and 101 New York State recipients (0.9%) sustained a hip fracture, giving an unadjusted event rate of 1.6 and 1.5 per 1000 years, respectively (P = .480). There were no differences in the cumulative incidence of all fractures or hip fractures. One-year mortality rates after any fracture (9% and 11%) or after a hip fracture (15% and 17%) were not different between cohorts. Contemporaneous English and New York State kidney transplant recipients have similar fracture rates and mortality rates postfracture.
2017-01-01
PURPOSE The aim of this study was to investigate the effect of reinforcing materials on the fracture resistances of glass fiber mesh- and Cr–Co metal mesh-reinforced maxillary complete dentures under fatigue loading. MATERIALS AND METHODS Glass fiber mesh- and Cr–Co mesh-reinforced maxillary complete dentures were fabricated using silicone molds and acrylic resin. A control group was prepared with no reinforcement (n = 15 per group). After fatigue loading was applied using a chewing simulator, fracture resistance was measured by a universal testing machine. The fracture patterns were analyzed and the fractured surfaces were observed by scanning electron microscopy. RESULTS After cyclic loading, none of the dentures showed cracks or fractures. During fracture resistance testing, all unreinforced dentures experienced complete fracture. The mesh-reinforced dentures primarily showed posterior framework fracture. Deformation of the all-metal framework caused the metal mesh-reinforced denture to exhibit the highest fracture resistance, followed by the glass fiber mesh-reinforced denture (P<.05) and the control group (P<.05). The glass fiber mesh-reinforced denture primarily maintained its original shape with unbroken fibers. River line pattern of the control group, dimples and interdendritic fractures of the metal mesh group, and radial fracture lines of the glass fiber group were observed on the fractured surfaces. CONCLUSION The glass fiber mesh-reinforced denture exhibits a fracture resistance higher than that of the unreinforced denture, but lower than that of the metal mesh-reinforced denture because of the deformation of the metal mesh. The glass fiber mesh-reinforced denture maintains its shape even after fracture, indicating the possibility of easier repair. PMID:28243388
Bakhtiyarova, S; Lesnyak, O; Kyznesova, N; Blankenstein, M A; Lips, P
2006-01-01
Vitamin D deficiency leads to secondary hyperparathyroidism and osteomalacia, and both conditions are associated with fractures, the most severe being hip fracture. The serum 25-hydroxyvitamin D level depends on latitude and season. Yekaterinburg is situated at a high latitude and the duration of winter is about 5 months. In this study, the serum 25(OH)D and PTH concentrations, and the prevalence of hypovitaminosis D in elderly people, inhabitants of Yekaterinburg, were investigated. The study was performed on 63 people with hip fracture (mean age, 68.8 years) and 97 independently living elderly people (mean age, 70.2 years). Serum 25(OH)D (mean+/-SD) in the hip fracture group was 22.4+/-11.4 nmol/L, significantly lower than in control group, which was 28.1+/-10.1 nmol/L. The percentage of patients with severe hypovitaminosis D (<25 nmol/L) in the hip fracture group was 65%, compared to 47% in the control group (p<0.05). The prevalence of hypovitaminosis D among hip fracture patients, as well as among independently living elderly people in Yekaterinburg, was high. Supplementation of vitamin D in elderly people with and without fracture might prevent secondary hyperparathyroidism, osteomalacia and fractures.
Self-Reported Fractures in Dermatitis Herpetiformis Compared to Coeliac Disease
Pasternack, Camilla; Mansikka, Eriika; Kaukinen, Katri; Hervonen, Kaisa; Reunala, Timo; Collin, Pekka; Mattila, Ville M.
2018-01-01
Dermatitis herpetiformis (DH) is a cutaneous manifestation of coeliac disease. Increased bone fracture risk is known to associate with coeliac disease, but this has been only scantly studied in DH. In this study, self-reported fractures and fracture-associated factors in DH were investigated and compared to coeliac disease. Altogether, 222 DH patients and 129 coeliac disease-suffering controls were enrolled in this study. The Disease Related Questionnaire and the Gastrointestinal Symptom Rating Scale and Psychological General Well-Being questionnaires were mailed to participants; 45 out of 222 (20%) DH patients and 35 out of 129 (27%) of the coeliac disease controls had experienced at least one fracture (p = 0.140). The cumulative lifetime fracture incidence did not differ between DH and coeliac disease patients, but the cumulative incidence of fractures after diagnosis was statistically significantly higher in females with coeliac disease compared to females with DH. The DH patients and the coeliac disease controls with fractures reported more severe reflux symptoms compared to those without, and they also more frequently used proton-pump inhibitor medication. To conclude, the self-reported lifetime bone fracture risk is equal for DH and coeliac disease. After diagnosis, females with coeliac disease have a higher fracture risk than females with DH. PMID:29538319
Lisiecki, Jeffrey; Zhang, Peng; Wang, Lu; Rinkinen, Jacob; De La Rosa, Sara; Enchakalody, Binu; Brownley, Robert Cameron; Wang, Stewart C; Buchman, Steven R; Levi, Benjamin
2013-09-01
Patients with mandibular fracture often have comorbidities and concomitant injuries making the decision for when and how to operate a challenge. Physicians describe "temporalis wasting" as a finding that indicates frailty; however, this is a subjective finding without quantitative values. In this study, we demonstrate that decreased morphomic values of the temporalis muscle and zygomatic bone are an objective measure of frailty associated with increased injury-induced morbidity as well as negative impact on overall hospital-based clinical outcomes in patients with mandible fracture. Computed tomographic (CT) scans from all patients with a diagnosis of a mandible fracture in the University of Michigan trauma registry and with a hospital admission were collected from the years 2004 to 2011. Automated, high-throughput CT analysis was used to reconstruct the anatomy and quantify morphomic values (temporalis volume, area and thickness, and zygomatic thickness) in these patients using MATLAB v13.0 (MathWorks Inc, Natick, MA, USA). Subsequently, a subset of 16 individuals with a Glasgow Coma Scale of 14 or 15 was analyzed to control for brain injury. Clinical data were obtained, and the association between morphomic measurements and clinical outcomes was evaluated using Pearson correlation for unadjusted analysis and multiple regression for adjusted analysis. The mean age of patients in the study was 47.1 years. Unadjusted analysis using Pearson correlation revealed that decreases in zygomatic bone thickness correlated strongly with increases in hospital, intensive care unit, and ventilator days (P < 0.0001, P = 0.0003, and P = 0.0017, respectively). Furthermore, we found that decreases in temporalis mean thickness correlated with increases in hospital and ventilator days (P = 0.0264 and P = 0.0306, respectively). Similarly, decreases in temporalis local mean thickness are significantly correlated with increases in hospital and ventilator days (P = 0.0232 and P = 0.0472, respectively). Decreased thicknesses of the zygomatic bone and temporalis muscle are significantly correlated with higher hospital, ventilator, and intensive care unit days in patients with mandibular fracture receiving reconstructive operations. This morphomic methodology provides an accurate, quantitative means to evaluate craniofacial trauma patient frailty, injury, and outcomes using routinely obtained CT scans. In the future, we plan to apply this approach to determine preoperative risk stratification and assist in surgical planning.
Hayashi, Hiroyuki; Nakashima, Daiki; Matsuoka, Hiroka; Iwai, Midori; Nakamura, Shugo; Kubo, Ayumi; Tomiyama, Naoki
2017-11-06
Upper-limb function is important in patients with hip fracture so they can perform activities of daily living and participate in leisure activities. Upper-limb function of these patients, however, has not been thoroughly investigated. The aim of this study was to evaluate the upper-limb motor and sensory functions in patients with hip fracture by comparing these functions with those of community-dwelling older adults (control group). We compared the results of motor and sensory function tests of upper-limb function - range of motion, strength, sensibility, finger dexterity, comprehensive hand function - between patients with hip fracture (n= 32) and the control group (n= 32). Patients with hip fracture had significantly reduced grip strength, pinch strength, finger dexterity, and comprehensive hand function compared with the control group. Most upper-limb functions are impaired in the patients with hip fracture. Thus, upper-limb function of patients with hip fracture should be considered during treatment.
FracPaQ: a MATLAB™ Toolbox for the Quantification of Fracture Patterns
NASA Astrophysics Data System (ADS)
Healy, D.; Rizzo, R. E.; Cornwell, D. G.; Timms, N.; Farrell, N. J.; Watkins, H.; Gomez-Rivas, E.; Smith, M.
2016-12-01
The patterns of fractures in deformed rocks are rarely uniform or random. Fracture orientations, sizes, shapes and spatial distributions often exhibit some kind of order. In detail, there may be relationships among the different fracture attributes e.g. small fractures dominated by one orientation, larger fractures by another. These relationships are important because the mechanical (e.g. strength, anisotropy) and transport (e.g. fluids, heat) properties of rock depend on these fracture patterns and fracture attributes. This presentation describes an open source toolbox to quantify fracture patterns, including distributions in fracture attributes and their spatial variation. Software has been developed to quantify fracture patterns from 2-D digital images, such as thin section micrographs, geological maps, outcrop or aerial photographs or satellite images. The toolbox comprises a suite of MATLAB™ scripts based on published quantitative methods for the analysis of fracture attributes: orientations, lengths, intensity, density and connectivity. An estimate of permeability in 2-D is made using a parallel plate model. The software provides an objective and consistent methodology for quantifying fracture patterns and their variations in 2-D across a wide range of length scales. Our current focus for the application of the software is on quantifying the fracture patterns in and around fault zones. There is a large body of published work on the quantification of relatively simple joint patterns, but fault zones present a bigger, and arguably more important, challenge. The method presented is inherently scale independent, and a key task will be to analyse and integrate quantitative fracture pattern data from micro- to macro-scales. Planned future releases will incorporate multi-scale analyses based on a wavelet method to look for scale transitions, and combining fracture traces from multiple 2-D images to derive the statistically equivalent 3-D fracture pattern.
Initiation and propagation of mixed mode fractures in granite and sandstone
NASA Astrophysics Data System (ADS)
Rück, Marc; Rahner, Roman; Sone, Hiroki; Dresen, Georg
2017-10-01
We investigate mixed mode fracture initiation and propagation in experimentally deformed granite and sandstone. We performed a series of asymmetric loading tests to induce fractures in cylindrical specimens at confining pressures up to 20 MPa. Loading was controlled using acoustic emission (AE) feedback control, which allows studying quasi-static fracture propagation for several hours. Location of acoustic emissions reveals distinct differences in spatial-temporal fracture evolution between granite and sandstone samples. Before reaching peak stress in experiments performed on granite, axial fractures initiate first at the edge of the indenter and then propagate through the entire sample. Secondary inclined fractures develop during softening of the sample. In sandstone, inclined shear fractures nucleate at peak stress and propagate through the specimen. AE source type analysis shows complex fracturing in both materials with pore collapse contributing significantly to fracture growth in sandstone samples. We compare the experimental results with numerical models to analyze stress distribution and energy release rate per unit crack surface area in the samples at different stages during fracture growth. We thereby show that for both rock types the energy release rate increases approximately linearly during fracture propagation. The study illuminates how different material properties modify fracture initiation direction under similar loading conditions.
Barr, R J; Stewart, A; Torgerson, D J; Reid, D M
2010-04-01
Randomised control trial of osteoporosis screening in 4,800 women aged 45-54 years was carried out. Screened group observed an increase of 7.9% in hormone replacement therapy (HRT) use (p < 0.001), 15% in other osteoporosis treatments (p < 0.001) and a 25.9% reduction in fracture risk compared with control. Screening for osteoporosis significantly increases treatment use and reduces fracture incidence. Population screening programmes can identify menopausal women with low bone mineral density (BMD) and elevated risk of future fracture but require to be proven effective by a randomised control trial. A total of 4,800 women, 45-54 years, were randomised in equal numbers to screening or no screening (control) groups. Following screening, those in the lowest quartile of BMD were advised to consider HRT. Nine years later, the effect of screening on the uptake of treatment and the incidence of fractures were assessed by postal questionnaire. Categorical differences were assessed using chi(2) test. Cox regression was used to assess hazard ratio (HR). Of the screened and the control groups, 52.4% vs 44.5%, respectively, reported taking HRT (p < 0.001). In addition, 36.6% of the screened vs 21.6% of the control groups reported the use of vitamin D, calcium, alendronate, etidronate or raloxifene (p < 0.001). In a per protocol analysis of verified incident fractures, a 25.9% reduction in risk of fractures (of any site) in the screened group was observed (HR = 0.741, 95% CI = 0.551-0.998 adjusted age, weight and height). Screening for osteoporosis as assessed by low bone density significantly increases the use of HRT and other treatments for osteoporosis and reduces fracture incidence.
Systemic Delivery of Free Chitosan Accelerates Femur Fracture Healing in Rats.
Shao, Peng; Wei, Yongzhong; Dass, Crispin R; Zhang, Guoying; Wu, Zhisheng
2018-01-01
Chitosan-containing compounds have been shown to be suitable for bone replacement, but few studies demonstrate the impact of the chitosan as a free drug on the fracture.In this study, we aimed to evaluate possible effects of free chitosan on fracture healing. Thirty adult male Sprague-Dawley rats with a mean body weight of 205 g (range from 200g to 210g) were randomly and equally divided into two groups. Standardized femur fractures were created in all rats. Treatments were administered intraperitoneally twice weekly at 1 mg chitosan per injection and the controls were administered physiological saline. The site of the fracture was compared with the control group at 1, 2 and 4 weeks after surgery (n=5 in each group). The weight, activity and reaction of the rats were observed at all the timepoints. Anterior-posterior radiographs and micro-CT scans of all fractures were taken after surgery, and the parameters included: the volume of callus that was calculated using the Perkins volume formula, BV/TV, BV, BMD of cortical bone, cortical thickness, and cortical number at the fracture sites. After sacrifice, fractured femurs from rats were dissected and carefully cleaned of muscle around the fracture callus to preserve callus integrity. Sections were stained with haematoxylin and eosin for histological evaluation of healing. Radiological (X-ray and micro-CT) evaluation showed that fracture healing of the experimental group was better than control group at the second week and fourth week. Histological evaluation revealed fracture healing of the experimental group was better than control group at the same time. There was no statistically significant difference in fracture healing between the two groups at the first week. Systemic delivery of free chitosan can accelerate the bone healing process in rat femur fracture at the early-middle stage. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Ou, S-M; Chen, Y-T; Shih, C-J; Tarng, D-C
2015-04-01
Urinary calculi were associated with higher risk of vertebral and upper limb fracture. Therefore, patients with urinary calculi should be evaluated carefully because they may have a higher risk of subsequent fracture later in life. The contribution of urinary calculi to reduced bone mineral density has been recognized. However, the association of urinary calculi with the risk of fracture remains inconclusive. The aim of the study was to determine the risk of overall fracture and fractures at different anatomic sites in patients with urinary calculi. The records of inpatients and outpatients with urinary calculi were retrieved from the Taiwan National Health Insurance Database from 2000 to 2010. Among patients with urinary calculi at the cohort entry, controls were matched using propensity scores on a 1:1 ratio. All subjects were followed up from the date of enrollment until fracture occurrence, death, or December 31, 2010. There were 46,243 Medicare beneficiaries with a diagnosis of urinary calculi and 46,243 controls without calculi enrolled. Among these patients, 6005 patients with a diagnosis of urinary calculi and 5339 controls developed fractures during a median follow-up period of 5.3 years. Patients with urinary calculi had a higher incidence of fracture compared with controls (23.9 versus 22.1 per 1000 person-years) and a greater risk of overall fractures (adjusted hazard ratio [aHR] 1.08, 95 % confidence interval [CI], 1.04-1.12), mainly located at the vertebrae (aHR 1.15, 95 % CI, 1.06-1.25) and upper limb (aHR 1.07, 95 % CI, 1.01-1.14), but the risk for hip fracture was not increased (aHR 1.09, 95 % CI, 0.96-1.22). Urinary calculus is independently associated with higher risk of subsequent fracture. Patients with urinary calculi should pay attention to the future vertebral and upper limb fractures.
Durmuş, Kasım; Turgut, Nergiz Hacer; Doğan, Mehtap; Tuncer, Ersin; Özer, Hatice; Altuntaş, Emine Elif; Akyol, Melih
2017-10-01
Mandibular fractures are the most common facial fractures. They can be treated by conservative techniques or by surgery. The authors hypothesized that the application of a single local dose of strontium chloride would accelerate the healing of subcondylar mandibular fractures, shorten the recovery time and prevent complications. The aim of the present pilot study was to evaluate the effects of a single local dose of strontium chloride on the healing of subcondylar mandibular fractures in rats. This randomized experimental study was carried out on 24 male Wistar albino rats. The rats were randomly divided into 3 groups: experimental group 1, receiving 3% strontium chloride; experimental group 2, receiving 5% strontium chloride; and the control group. A full thickness surgical osteotomy was created in the subcondylar area. A single dose of strontium solution (0.3 cc/site) was administered locally by injection on the bone surfaces of the fracture line created. Nothing was administered to the control group. The mandibles were dissected on postoperative day 21. The fractured hemimandibles were submitted to histopathological examination. The median bone fracture healing score was 9 (range: 7-9) in experimental group 1; 8 (range: 7-10) in experimental group 2; and 7.50 (range: 7-8) in the control group. When the groups were compared in terms of bone healing scores, there was a statistically significant difference between experimental group 1 and the control group (p < 0.05). This study is the first to show that local strontium may have positive effects on the healing of subcondylar mandibular fractures. In the authors' opinion, 3% strontium was beneficial for accelerating facial skeleton consolidation and bone regeneration in rat subcondylar mandibular fractures. This treatment procedure may be combined with closed fracture treatment or a conservative approach.
Women with previous stress fractures show reduced bone material strength
Duarte Sosa, Daysi; Fink Eriksen, Erik
2016-01-01
Background and purpose — Bone fragility is determined by bone mass, bone architecture, and the material properties of bone. Microindentation has been introduced as a measurement method that reflects bone material properties. The pathogenesis of underlying stress fractures, in particular the role of impaired bone material properties, is still poorly understood. Based on the hypothesis that impaired bone material strength might play a role in the development of stress fractures, we used microindentation in patients with stress fractures and in controls. Patients and methods — We measured bone material strength index (BMSi) by microindentation in 30 women with previous stress fractures and in 30 normal controls. Bone mineral density by DXA and levels of the bone markers C-terminal cross-linking telopeptide of type-1 collagen (CTX) and N-terminal propeptide of type-1 procollagen (P1NP) were also determined. Results — Mean BMSi in stress fracture patients was significantly lower than in the controls (SD 72 (8.7) vs. 77 (7.2); p = 0.02). The fracture subjects also had a significantly lower mean bone mineral density (BMD) than the controls (0.9 (0.02) vs. 1.0 (0.06); p = 0.03). Bone turnover—as reflected in serum levels of the bone marker CTX—was similar in both groups, while P1NP levels were significantly higher in the women with stress fractures (55 μg/L vs. 42 μg/L; p = 0.03). There was no correlation between BMSi and BMD or bone turnover. Interpretation — BMSi was inferior in patients with previous stress fracture, but was unrelated to BMD and bone turnover. The lower values of BMSi in patients with previous stress fracture combined with a lower BMD may contribute to the increased propensity to develop stress fractures in these patients. PMID:27321443
Lai, Shih-Wei; Liao, Kuan-Fu; Liao, Chien-Chang; Muo, Chih-Hsin; Liu, Chiu-Shong; Sung, Fung-Chang
2010-09-01
Few studies have addressed the association between polypharmacy and hip fracture using population data. We conducted a population-based case-control study to investigate whether polypharmacy increases the risk for hip fracture in the elderly. We used insurance claims data from the Taiwan Bureau of National Health Insurance, a universal insurance program with a coverage rate of more than 98% of the population in Taiwan. We identified 2328 elderly patients with newly diagnosed hip fracture during the period 2005-2007. We randomly selected 9312 individuals without hip fracture to serve as the control group. Patient characteristics, drugs prescribed by physicians, and all types of hip fracture were ascertained. The odds ratio (OR) of hip fracture in association with the number of medications used per day in previous years was assessed.We found that patients were older than controls, predominantly female, and more likely to use 5 or more drugs (22.2% vs. 9.3%, p < 0.0001). The OR of hip fracture increased with the number of medications used per day and with age. Multivariate logistic regression analysis revealed that the overall OR for patients using 10 or more drugs was 8.42 (95% confidence interval [CI], 4.73-15.0) compared with patients who used 0-1 drug per day. However, age-specific analysis revealed that the risk for hip fracture was 23 times greater for patients aged > or = 85 years who used 10 or more drugs than for those aged 65-74 years who used 0-1 drug after controlling for covariates (OR, 23.0; 95% CI, 3.77-140).We conclude that the risk of hip fracture in older people increases with the number of medications used, especially in women. Age interacts with the daily medications for the risk of hip fracture.
Loughridge, A B; Hess, A M; Parkin, T D; Kawcak, C E
2017-03-01
Changes in subchondral bone density, induced by the repetitive cyclical loading of exercise, may potentiate fatigue damage and the risk of fracture. To use computed tomography (CT) to characterise bone density patterns at the articular surface of the third metacarpal bone in racehorses with and without lateral condylar fractures. Case control METHODS: Computed tomographic images of the distal articulating surface of the third metacarpal bone were obtained from Thoroughbred racehorses subjected to euthanasia in the UK. Third metacarpal bones were divided into 3 groups based on lateral condyle status; fractured (FX, n = 42), nonfractured contralateral condyle (NFX, n = 42) and control condyles from horses subjected to euthanasia for reasons unrelated to the third metacarpal bone (control, n = 94). Colour CT images were generated whereby each colour represented a range of pixel values and thus a relative range of bone density. A density value was calculated qualitatively by estimating the percentage of each colour within a specific region. Subchondral bone density was assessed in 6 regions from dorsal to palmar and 1 mm medial and lateral to the centre of the lateral parasagittal groove in NFX and control condyles and 1 mm medial and lateral to the fracture in FX condyles. Bone density was significantly higher in the FX and NFX condyles compared with control condyles for all 6 regions. A significantly higher bone density was observed in FX condyles relative to NFX condyles in the lateral middle and lateral palmar regions. Fractured condyles had increased heterogeneity in density among the 6 regions of interest compared with control and NFX condyles. Adjacent to the fracture, a focal increase in bone density and increased heterogeneity of density were characteristic of limbs with lateral condylar fractures compared with control and NFX condyles. These differences may represent pathological changes in bone density that increase the risk for lateral condylar fractures in racehorses. © 2015 EVJ Ltd.
Complications of ankle fracture in patients with diabetes.
Chaudhary, Saad B; Liporace, Frank A; Gandhi, Ankur; Donley, Brian G; Pinzur, Michael S; Lin, Sheldon S
2008-03-01
Ankle fractures in patients with diabetes mellitus have long been recognized as a challenge to practicing clinicians. Complications of impaired wound healing, infection, malunion, delayed union, nonunion, and Charcot arthropathy are prevalent in this patient population. Controversy exists as to whether diabetic ankle fractures are best treated noninvasively or by open reduction and internal fixation. Patients with diabetes are at significant risk for soft-tissue complications. In addition, diabetic ankle fractures heal, but significant delays in bone healing exist. Also, Charcot ankle arthropathy occurs more commonly in patients who were initially undiagnosed and had a delay in immobilization and in patients treated nonsurgically for displaced ankle fractures. Several techniques have been described to minimize complications associated with diabetic ankle fractures (eg, rigid external fixation, use of Kirschner wires or Steinmann pins to increase rigidity). Regardless of the specifics of treatment, adherence to the basic principles of preoperative planning, meticulous soft-tissue management, and attention to stable, rigid fixation with prolonged, protected immobilization are paramount in minimizing problems and yielding good functional outcomes.
RSRM nozzle actuator bracket/lug fracture mechanics qualification test
NASA Technical Reports Server (NTRS)
Kelley, Peggy
1993-01-01
This is the final report for the actuator bracket/lug fracture mechanics qualification test. The test plan (CTP-0071) outlined a two-phase test program designed to answer questions about the fracture criticality of the redesigned solid rocket motor (RSRM) nozzle actuator bracket. An analysis conducted using the NASA/FLAGRO fracture mechanics computer program indicated that the actuator bracket might be a fracture critical component. In the NASA/FLAGRO analysis, a simple lug model was used to represent the actuator bracket. It was calculated that the bracket would fracture if subjected to an actuator stall load in the presence of a 0.10 in. corner crack at the actuator attachment hole. The 0.10 in. crack size corresponds to the nondestructive inspection detectability limit for the actuator bracket. The inspection method used is the dye penetrant method. The actuator stall load (103,424 lb) is the maximum load which the actuator bracket is required to withstand during motor operation. This testing was designed to establish the accuracy of the analytical model and to directly determine whether the actuator bracket is capable of meeting fracture mechanics safe-life requirements.
NASA Astrophysics Data System (ADS)
Poszwa, A. C.; Coleman, M. L.; Pouya, A.; Ader, M.; Bounenni, A.
2003-04-01
Planning oil production from a chalk reservoir oilfield is difficult because the matrix usually has low permeability despite its high porosity. Most oil is thought to come from fracture porosity but the matrix contribution should increase as compaction occurs during production. To better understand the respective contributions from matrix and fracture, we studied the geochemical characteristics of fluids using high-pressure brine flow experiments on chalk cores. During the experiment axial load was changed relative to confining pressure to induce fractures and to close them again. We used chlorine stable isotope variations to study fluid pathway, because chlorine is a chemically conservative element in sedimentary systems and its isotopes fractionate only with physical processes like diffusion or adsorption that could occur mainly in the chalk matrix. A first experiment was performed on a very porous chalk from Henley (on-shore UK) and using a low-salinity brine. Large variations of brine Cl isotope composition were observed (from -0.56 to +0.08 per mil). The variations were correlated positively with the brine flux through the chalk and the permeability of the rock, both parameters controlled by the rock fracturing. A second experiment used brine with salinity similar to that of seawater. In this case, chemical and isotopic variations were not significant. From the beginning, the chalk structure seems to have been destroyed very quickly (induced fracture porosity collapsed) possibly because of the fluid nature, so that whatever pressure was applied, the permeability did not change significantly. Using Valhall reservoir chalk (offshore Norwegian North Sea) and fluid half the salinity of seawater in a third experiment, we obtained a large range of permeabilities. Brine isotopic trends were very similar on average to those of the first experiment even though variations were smaller (Cl isotopes from -0.09 to +0.29 per mil) and not significantly correlated simply to permeability values. The highest isotopic values were in brine flowed through chalk when the permeability was high and fractures opened; the lowest values were in brine flowed through the chalk when its permeability was reduced by closing fractures and increasing the relative contribution from matrix flow where diffusion processes fractionated chlorine isotopes. From this work it seems that the relative contributions from fracture and matrix permeability in reservoirs can be estimated from the geochemical compositions of brines that flowed from them.
High prevalence of radiological vertebral fractures in HIV-infected males.
Torti, Carlo; Mazziotti, Gherardo; Soldini, Pier Antonio; Focà, Emanuele; Maroldi, Roberto; Gotti, Daria; Carosi, Giampiero; Giustina, Andrea
2012-06-01
Age-related co-morbidities including osteoporosis are relevant in patients responding to combination antiretroviral therapy (cART). Vertebral fractures are common osteoporotic fractures and their diagnosis is useful for managing at-risk individuals. However, there are few data from HIV-infected patients. Therefore, the aim of this study was to determine the prevalence of and factors associated with vertebral fractures in a population of HIV-infected males. A cross-sectional study of 160 HIV-infected patients with available chest X-rays was conducted from 1998 to 2010. One hundred and sixty-three males with comparable age and with no history of HIV infection were recruited as controls. Semi-quantitative evaluation of vertebral heights in lateral chest X-rays and quantitative morphometry assessment of centrally digitized images using dedicated morphometry software were utilized to detect prevalent vertebral fractures. The result showed that the vertebral fractures were detected in 43/160 (26.9%) HIV-infected patients and in 21/163 (12.9%) controls (P = 0.002). In HIV-infected patients with fractures, 27 had two or more fractures and ten patients had severe fractures. The prevalence of any fractures and multiple fractures in HIV-infected patients receiving cART (29.6 and 20.0%) was slightly higher than in HIV-infected patients not exposed to cART (17.1 and 5.7%), but significantly higher than control subjects (12.9 and 3.7%). At multivariable analyses, body mass index and diabetes mellitus were independently correlated with vertebral fractures in HIV-infected patients. We concluded that a significant proportion of HIV-infected males receiving cART showed vertebral fractures. Furthermore, proactive diagnosis of vertebral fragility fractures is particularly relevant in patients who are overweight or suffer from diabetes.
Rehabilitation Practitioners' Prioritized Care Processes in Hip Fracture Post-Acute Care
Kim, Lauren H.; Leland, Natalie E.
2017-01-01
Aims Occupational and physical therapy in post-acute care (PAC) has reached the point where quality indicators for hip fracture are needed. This study characterizes the practitioners' prioritized hip fracture rehabilitation practices, which can guide future quality improvement initiatives. Methods Ninety-two practitioners participating in a parent mixed methods study were asked to rank a series of evidence-based best practices across five clinical domains (assessment, intervention, discharge planning, caregiver training and patient education). Results Prioritized practices reflected patient-practitioner collaboration, facilitating an effective discharge, and preventing adverse events. The highest endorsed care processes include: developing meaningful goals with patient input (84%) in assessment, using assistive devices in intervention (75%) and patient education (65%), engaging the patient and caregiver (50%) in discharge planning, and fall prevention (60%) in caregiver education. Conclusions Practitioners identified key care priorities. This study lays the foundation for future work evaluating the extent to which these practices are delivered in PAC. PMID:28989216
Fracture control procedures for aircraft structural integrity
NASA Technical Reports Server (NTRS)
Wood, H. A.
1972-01-01
The application of applied fracture mechanics in the design, analysis, and qualification of aircraft structural systems are reviewed. Recent service experiences are cited. Current trends in high-strength materials application are reviewed with particular emphasis on the manner in which fracture toughness and structural efficiency may affect the material selection process. General fracture control procedures are reviewed in depth with specific reference to the impact of inspectability, structural arrangement, and material on proposed analysis requirements for safe crack growth. The relative impact on allowable design stress is indicated by example. Design criteria, material, and analysis requirements for implementation of fracture control procedures are reviewed together with limitations in current available data techniques. A summary of items which require further study and attention is presented.
Controlled shear/tension fixture
Hsueh, Chun-Hway [Knoxville, TN; Liu, Chain-tsuan [Knoxville, TN; George, Easo P [Knoxville, TN
2012-07-24
A test fixture for simultaneously testing two material test samples is provided. The fixture provides substantially equal shear and tensile stresses in each test specimens. By gradually applying a load force to the fixture only one of the two specimens fractures. Upon fracture of the one specimen, the fixture and the load train lose contact and the second specimen is preserved in a state of upset just prior to fracture. Particular advantages of the fixture are (1) to control the tensile to shear load on the specimen for understanding the effect of these stresses on the deformation behavior of advanced materials, (2) to control the location of fracture for accessing localized material properties including the variation of the mechanical properties and residual stresses across the thickness of advanced materials, (3) to yield a fractured specimen for strength measurement and an unfractured specimen for examining the microstructure just prior to fracture.
Do Tibial Plateau Fractures Worsen Outcomes of Knee Ligament Injuries? A Matched Cohort Analysis
Cinque, Mark E.; Godin, Jonathan A.; Moatshe, Gilbert; Chahla, Jorge; Kruckeberg, Bradley M.; Pogorzelski, Jonas; LaPrade, Robert F.
2017-01-01
Background: Tibial plateau fractures account for a small portion of all fractures; however, these fractures can pose a surgical challenge when occurring concomitantly with ligament injuries. Purpose/Hypothesis: The purpose of this study was to compare 2-year outcomes of soft tissue reconstruction with or without a concomitant tibial plateau fracture and open reduction internal fixation. We hypothesized that patients with a concomitant tibial plateau fracture at the time of soft tissue surgery would have inferior outcomes compared with patients without an associated tibial plateau fracture. Study Design: Cohort study; Level of evidence, 3. Methods: Forty patients were included in this study: 8 in the fracture group and 32 in the matched control group. Inclusion criteria for the fracture group included patients who were at least 18 years old at the time of surgery and sustained a tibial plateau fracture and a concomitant injury of the anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament, or fibular collateral ligament in isolation or any combination of cruciate or collateral ligaments and who subsequently underwent isolated or combined ligament reconstruction. Patients were excluded if they underwent prior ipsilateral knee surgery, sustained additional bony injuries, or sustained an isolated extra-articular ligament injury at the time of injury. Each patient with a fracture was matched with 4 patients from a control group who had no evidence of a tibial plateau fracture but underwent the same soft tissue reconstruction procedure. Results: Patients in the fracture group improved significantly from preoperatively to postoperatively with respect to Short Form–12 (P < .05) and Western Ontario and McMaster Universities Osteoarthritis Index total scores (P < .05). The Lysholm (P = .075) and Tegner scores (P = .086) also improved, although this was not statistically significant. Patients in the control group improved significantly from preoperatively to postoperatively across all measured scores. A comparison of the postoperative results between the 2 groups showed no statistically significant difference. Conclusion: The presence of a tibial plateau fracture in conjunction with a ligamentous knee injury did not have a negative effect on postoperative patient-reported outcomes. Patient-reported outcome scores after surgery in both the fracture and control groups improved beyond the minimally clinically important difference, indicating that the presence of a fracture did not detract from the outcomes observed in patients without fractures undergoing concomitant ligament reconstruction. PMID:28840154
Levothyroxine treatment and occurrence of fracture of the hip.
Sheppard, Michael C; Holder, Roger; Franklyn, Jayne A
2002-02-11
Levothyroxine sodium is widely prescribed and has been implicated as a cause of reduction in bone mineral density and, therefore, suggested to be a major contributor to the risk of osteoporotic fractures. To investigate whether levothyroxine use increases the risk of developing osteoporotic fractures. We conducted a population-based, case-control analysis of the risk of a femur fracture in a large cohort of patients who had been prescribed levothyroxine. We used the United Kingdom General Practice (primary care) Research Database to identify 23,183 patients who had been prescribed long-term thyroid hormone therapy and to identify for each patient taking levothyroxine 4 controls matched for age, sex, primary care practice, and duration of registration on the database. The number of patients who had sustained a fracture of the proximal femur was ascertained for each group, together with drug therapies and medical diagnoses likely to affect fracture risk. Of the 23,183 patients prescribed thyroid hormone, a mean +/- SE of 1.61% +/- 0.08% had sustained a fracture of the femur, compared with 1.44% +/- 0.04% of 92,732 controls (P =.06). When analyzed according to sex, a significant difference in rate of fracture between patients taking levothyroxine and controls was found in males (P =.008). Compared with controls, patients taking levothyroxine had higher reported rates of medical diagnoses and therapies, potentially confounding the fracture risk. Independent predictors of the occurrence of fracture after adjustment for other factors were age (adjusted odds ratio [AOR], 1.11; 95% confidence interval [CI], 1.10-1.11; P<.001), medical diagnoses including rheumatoid arthritis (AOR in females, 1.69; 95% CI, 1.27-2.26; P<.001), excessive use of alcohol (AOR in females, 3.05; 95% CI, 1.94-4.76; P<.001), and prescription of drugs (eg, anticonvulsants; AOR in females, 2.49; 95% CI, 2.00-3.09; P<.001). Prescription of levothyroxine was an independent predictor of fracture occurrence in males (AOR, 1.69; 95% CI, 1.12-2.56; P =.01) but not females (AOR, 1.03; 95% CI, 0.92-1.16; P =.60). The lack of association between fracture and levothyroxine prescription in the whole cohort is reassuring, although an independent association between levothyroxine prescription and fracture occurrence in male patients suggests that levothyroxine may contribute to fracture risk in this specific group.
NASA Astrophysics Data System (ADS)
Ozkaya, Sait I.
2018-03-01
Fracture corridors are interconnected large fractures in a narrow sub vertical tabular array, which usually traverse entire reservoir vertically and extended for several hundreds of meters laterally. Fracture corridors with their huge conductivities constitute an important element of many fractured reservoirs. Unlike small diffuse fractures, actual fracture corridors must be mapped deterministically for simulation or field development purposes. Fracture corridors can be identified and quantified definitely with borehole image logs and well testing. However, there are rarely sufficient image logs or well tests, and it is necessary to utilize various fracture corridor indicators with varying degrees of reliability. Integration of data from many different sources, in turn, requires a platform with powerful editing and layering capability. Available commercial reservoir characterization software packages, with layering and editing capabilities, can be cost intensive. CAD packages are far more affordable and may easily acquire the versatility and power of commercial software packages with addition of a small software toolbox. The objective of this communication is to present FRACOR, a software toolbox which enables deterministic 2D fracture corridor mapping and modeling on AutoCAD platform. The FRACOR toolbox is written in AutoLISPand contains several independent routines to import and integrate available fracture corridor data from an oil field, and export results as text files. The resulting fracture corridor maps consists mainly of fracture corridors with different confidence levels from combination of static and dynamic data and exclusion zones where no fracture corridor can exist. The exported text file of fracture corridors from FRACOR can be imported into an upscaling programs to generate fracture grid for dual porosity simulation or used for field development and well planning.
BURGOYNE, L. L.; PEREIRAS, L. A.; BERTANI, L. A.; KADDOUM, R. N.; NEEL, M.; FAUGHNAN, L. G.; ANGHELESCU, D. L.
2013-01-01
SUMMARY We report three cases of children with osteosarcoma and pathologic fractures treated with long-term continuous nerve blocks for preoperative pain control. One patient with a left distal femoral diaphysis fracture had a femoral continuous nerve block catheter for 41 days without complications. Another with a fractured left proximal femoral shaft had three femoral continuous nerve block catheters for 33, 26 and 22 days respectively. The third patient, whose right proximal humerus was fractured, had a brachial plexus continuous nerve block catheter for 36 days without complication. In our experience, prolonged use of continuous nerve block is safe and effective in children with pathologic fractures for preoperative pain control. PMID:22813501
Pure Varus Injury to the Knee Joint.
Yoo, Jae Ho; Lee, Jung Ha; Chang, Chong Bum
2015-06-01
A 30-year-old male was involved in a car accident. Radiographs revealed a depressed marginal fracture of the medial tibial plateau and an avulsion fracture of the fibular head. Magnetic resonance imaging showed avulsion fracture of Gerdy's tubercle, injury to the posterior cruciate ligament (PCL), posterior horn of the medial meniscus, and the attachments of the lateral collateral ligament and the biceps femoris tendon. The depressed fracture of the medial tibial plateau was elevated and stabilized using a cannulated screw and washer. The injured lateral and posterolateral corner (PLC) structures were repaired and augmented by PLC reconstruction. However, the avulsion fracture of Gerdy's tubercle was not fixed because it was minimally displaced and the torn PCL was also not repaired or reconstructed. We present a unique case of pure varus injury to the knee joint. This case contributes to our understanding of the mechanism of knee injury and provides insight regarding appropriate treatment plans for this type of injury.
Fracture resistance of Kevlar-reinforced poly(methyl methacrylate) resin: a preliminary study.
Berrong, J M; Weed, R M; Young, J M
1990-01-01
The reinforcing effect of Kevlar fibers incorporated in processed poly(methyl methacrylate) resin samples was studied using 0% (controls), 0.5%, 1%, and 2% by weight of the added fibers. The samples were subjected to impact testing to determine fracture resistance, and sample groups were statistically compared using an ANOVA. Each reinforced sample had significantly greater fracture resistance (P less than 0.05) than the control, and no difference was found either within or between control groups. The use of reinforcing Kevlar fibers appears to enhance the fracture resistance of acrylic resin denture base materials.
Park, Moon Seok; Chung, Chin Youb; Choi, In Ho; Kim, Tae Won; Sung, Ki Hyuk; Lee, Seung Yeol; Lee, Sang Hyeong; Kwon, Dae Gyu; Park, Jung Woo; Kim, Tae Gyun; Choi, Young; Cho, Tae-Joon; Yoo, Won Joon; Lee, Kyoung Min
2013-09-01
Fractures which need urgent or emergency treatment are common in children and adolescents. This study investigated the incidence patterns of pediatric and adolescent orthopaedic fractures according to age groups and seasons in South Korea based on population data. Data on the number of pediatric and adolescent patients under the age of 18 years who utilized medical services due to fractures were retrieved from the Health Insurance Review and Assessment service in South Korea. The data included four upper extremity and two lower extremity fractures according to four age groups (0-4 years, 5-9 years, 10-14 years, and 15-18 years). Incidences of the fractures were calculated as the incidence per 10,000 per year, and patterns according to age groups and seasons were demonstrated. The annual incidence of clavicle, distal humerus, both forearm bone, distal radius, femoral shaft and tibial shaft fractures were 27.5, 34.6, 7.7, 80.1, 2.5, and 9.6 per 10,000 per year in children and adolescents, respectively. Clavicle and distal radius fractures showed significant seasonal variation for all age groups but femoral shaft fracture showed no significant seasonal variation for any of the age groups. The four upper extremity fractures tended to show greater variations than the two lower extremity fractures in the nationwide database in South Korea. The study results are believed to be helpful in the planning and assignment of medical resources for fracture management in children and adolescents.
Siletz, Anaar; Faltermeier, Claire; Singer, Emily S.; Hu, Q. Lina; Ko, Clifford Y.; Kates, Stephen L.; Maggard-Gibbons, Melinda; Wick, Elizabeth
2018-01-01
Background: Enhanced recovery pathways (ERPs) have been shown to improve patient outcomes in a variety of contexts. This review summarizes the evidence and defines a protocol for perioperative care of patients with hip fracture and was conducted for the Agency for Healthcare Research and Quality safety program for improving surgical care and recovery. Study Design: Perioperative care was divided into components or “bins.” For each bin, a semisystematic review of the literature was conducted using MEDLINE with priority given to systematic reviews, meta-analyses, and randomized controlled trials. Observational studies were included when higher levels of evidence were not available. Existing guidelines for perioperative care were also incorporated. For convenience, the components of care that are under the auspices of anesthesia providers will be reported separately. Recommendations for an evidence-based protocol were synthesized based on review of this evidence. Results: Eleven bins were identified. Preoperative risk factor bins included nutrition, diabetes mellitus, tobacco use, and anemia. Perioperative management bins included thromboprophylaxis, timing of surgery, fluid management, drain placement, early mobilization, early alimentation, and discharge criteria/planning. Conclusions: This review provides the evidence basis for an ERP for perioperative care of patients with hip fracture. PMID:29844947
Risk Assessment of Bone Fracture During Space Exploration Missions to the Moon and Mars
NASA Technical Reports Server (NTRS)
Lewandowski, Beth E.; Myers, Jerry G.; Nelson, Emily S.; Licatta, Angelo; Griffin, Devon
2007-01-01
The possibility of a traumatic bone fracture in space is a concern due to the observed decrease in astronaut bone mineral density (BMD) during spaceflight and because of the physical demands of the mission. The Bone Fracture Risk Module (BFxRM) was developed to quantify the probability of fracture at the femoral neck and lumbar spine during space exploration missions. The BFxRM is scenario-based, providing predictions for specific activities or events during a particular space mission. The key elements of the BFxRM are the mission parameters, the biomechanical loading models, the bone loss and fracture models and the incidence rate of the activity or event. Uncertainties in the model parameters arise due to variations within the population and unknowns associated with the effects of the space environment. Consequently, parameter distributions were used in Monte Carlo simulations to obtain an estimate of fracture probability under real mission scenarios. The model predicts an increase in the probability of fracture as the mission length increases and fracture is more likely in the higher gravitational field of Mars than on the moon. The resulting probability predictions and sensitivity analyses of the BFxRM can be used as an engineering tool for mission operation and resource planning in order to mitigate the risk of bone fracture in space.
NASA Technical Reports Server (NTRS)
Lewandowski, Beth E.; Myers, Jerry G.; Sulkowski, C.; Ruehl, K.; Licata, A.
2008-01-01
The possibility of bone fracture in space is a concern due to the negative impact it could have on a mission. The Bone Fracture Risk Module (BFxRM) developed at the NASA Glenn Research Center is a statistical simulation that quantifies the probability of bone fracture at specific skeletal locations for particular activities or events during space exploration missions. This paper reports fracture probability predictions for the proximal femur and wrist resulting from a fall to the side during an extravehicular activity (EVA) on specific days of lunar and Martian exploration missions. The risk of fracture at the proximal femur on any given day of the mission is small and fairly constant, although it is slightly greater towards the end of the mission, due to a reduction in proximal femur bone mineral density (BMD). The risk of wrist fracture is greater than the risk of hip fracture and there is an increased risk on Mars since it has a higher gravitational environment than the moon. The BFxRM can be used to help manage the risk of bone fracture in space as an engineering tool that is used during mission operation and resource planning.
Risk Assessment of Bone Fracture During Space Exploration Missions to the Moon and Mars
NASA Technical Reports Server (NTRS)
Lewandowski, Beth E.; Myers, Jerry G.; Nelson, Emily S.; Griffin, Devon
2008-01-01
The possibility of a traumatic bone fracture in space is a concern due to the observed decrease in astronaut bone mineral density (BMD) during spaceflight and because of the physical demands of the mission. The Bone Fracture Risk Module (BFxRM) was developed to quantify the probability of fracture at the femoral neck and lumbar spine during space exploration missions. The BFxRM is scenario-based, providing predictions for specific activities or events during a particular space mission. The key elements of the BFxRM are the mission parameters, the biomechanical loading models, the bone loss and fracture models and the incidence rate of the activity or event. Uncertainties in the model parameters arise due to variations within the population and unknowns associated with the effects of the space environment. Consequently, parameter distributions were used in Monte Carlo simulations to obtain an estimate of fracture probability under real mission scenarios. The model predicts an increase in the probability of fracture as the mission length increases and fracture is more likely in the higher gravitational field of Mars than on the moon. The resulting probability predictions and sensitivity analyses of the BFxRM can be used as an engineering tool for mission operation and resource planning in order to mitigate the risk of bone fracture in space.
Modelling Laccoliths: Fluid-Driven Fracturing in the Lab
NASA Astrophysics Data System (ADS)
Ball, T. V.; Neufeld, J. A.
2017-12-01
Current modelling of the formation of laccoliths neglects the necessity to fracture rock layers for propagation to occur [1]. In magmatic intrusions at depth the idea of fracture toughness is used to characterise fracturing, however an analogue for near surface intrusions has yet to be explored [2]. We propose an analytical model for laccolith emplacement that accounts for the energy required to fracture at the tip of an intrusion. For realistic physical parameters we find that a lag region exists between the fluid magma front and the crack tip where large negative pressures in the tip cause volatiles to exsolve from the magma. Crucially, the dynamics of this tip region controls the spreading due to the competition between viscous forces and fracture energy. We conduct a series of complementary experiments to investigate fluid-driven fracturing of adhered layers and confirm the existence of two regimes: viscosity dominant spreading, controlled by the pressure in the lag region, and fracture energy dominant spreading, controlled by the energy required to fracture layers. Our experiments provide the first observations, and evolution, of a vapour tip. These experiments and our simplified model provide insight into the key physical processes in near surface magmatic intrusions with applications to fluid-driven fracturing more generally. Michaut J. Geophys. Res. 116(B5), B05205. Bunger & Cruden J. Geophys. Res. 116(B2), B02203.
Bone density of the radius, spine, and proximal femur in osteoporosis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mazess, R.B.; Barden, H.; Ettinger, M.
1988-02-01
Bone mineral density (BMD) was measured in 140 normal young women (aged 20 to 39 years) and in 423 consecutive women over age 40 referred for evaluation of osteoporosis. Lumbar spine and proximal femur BMD was measured using dual-photon absorptiometry (/sup 153/Gd), whereas the radius shaft measurement used single-photon absorptiometry (/sup 125/I). There were 324 older women with no fractures, of which 278 aged 60 to 80 years served as age-matched controls. There were 99 women with fractures including 32 with vertebral and 22 with hip fractures. Subsequently, another 25 women with hip fractures had BMD measured in another laboratory;more » their mean BMD was within 2% of that of the original series. The mean age in both the nonfracture and fracture groups was 70 +/- 5 years. The BMD in the age-matched controls was 20% to 25% below that of normal young women for the radius, spine, and femur, but the Ward's triangle region of the femur showed even greater loss (35%). The mean BMD at all sites in the crush fracture cases was about 10% to 15% below that of age-matched controls. Spinal abnormality was best discriminated by spine and femoral measurements (Z score about 0.9). In women with hip fractures, the BMD was 10% below that of age-matched controls for the radius and the spine, and the BMD for the femoral sites was about 25% to 30% below that of age-matched control (Z score about 1.6). Femoral densities gave the best discrimination of hip fracture cases and even reflected spinal osteopenia. In contrast, neither the spine nor the radius reflected the full extent of femoral osteopenia in hip fracture.« less
Nordvall, Helena; Glanberg-Persson, Gunhild; Lysholm, Jack
2007-04-01
A fracture of the distal radius is considered to indicate an increased risk of future fractures, especially a hip fracture. The main causes may be osteoporosis or a tendency to fall, separately or in combination. 93 women and 5 men with a recent radius fracture and the same number of controls were measured with a heel-DXL and asked to complete one questionnaire on their quality of life (SF-36), and one on risk factors. The mean T-score of the patients was -2.1, and for the controls it was -1.9 (p = 0.3). The patients aged over 64 years had a history of falling more often than the corresponding controls (p = 0.01), but there was no difference in T-score. By contrast, patients 45-64 years of age showed a non-significant, lower T-score (p = 0.09), but there was no difference concerning their history of falling. For all other risk factors, no differences were found between the patients and the controls. There were significant differences between the patients and the controls in some of the functions in the SF-36, due to the radius fracture. This study indicates that the underlying cause of a distal radius fracture may be different in patients aged 45-64 years and those who are more than 64 years old.
Distinct Element Method modelling of fold-related fractures in a multilayer sequence
NASA Astrophysics Data System (ADS)
Kaserer, Klemens; Schöpfer, Martin P. J.; Grasemann, Bernhard
2017-04-01
Natural fractures have a significant impact on the performance of hydrocarbon systems/reservoirs. In a multilayer sequence, both the fracture density within the individual layers and the type of fracture intersection with bedding contacts are key parameters controlling fluid pathways. In the present study the influence of layer stacking and interlayer friction on fracture density and connectivity within a folded sequence is systematically investigated using 2D Distinct Element Method modelling. Our numerical approach permits forward modelling of both fracture nucleation/propagation/arrest and (contemporaneous) frictional slip along bedding planes in a robust and mechanically sound manner. Folding of the multilayer sequence is achieved by enforcing constant curvature folding by means of a velocity boundary condition at the model base, while a constant overburden pressure is maintained at the model top. The modelling reveals that with high bedding plane friction the multilayer stack behaves mechanically as a single layer so that the neutral surface develops in centre of the sequence and fracture spacing is controlled by the total thickness of the folded sequence. In contrast, low bedding plane friction leads to decoupling of the individual layers (flexural slip folding) so that a neutral surface develops in the centre of each layer and fracture spacing is controlled by the thickness of the individual layers. The low interfacial friction models illustrate that stepping of fractures across bedding planes is a common process, which can however have two contrasting origins: The mechanical properties of the interface cause fracture stepping during fracture propagation. Originally through-going fractures are later offset by interfacial slip during folding. A combination of these two different origins may lead to (apparently) inconsistent fracture offsets across bedding planes within a flexural slip fold.
Lv, Jiang-Tao; Zhang, Ying-Ying; Tian, Shao-Qi; Sun, Kang
2016-05-01
To assess the serum of 25-hydroxyvitamin D (25(OH)D) and intact parathyroid hormone (iPTH) levels in postmenopausal women from northern China with hip and upper limb fractures. Case-control. Affiliated Hospital of Qingdao University. Postmenopausal women diagnosed with hip fracture (n = 335) and matched controls without fracture (n = 335). Between 2011 and 2013, fasting venous samples were analyzed for 25(OH)D, iPTH, alkaline phosphatase (ALP), calcium, and phosphorus. All women completed a standardized questionnaire designed to document putative risk factors for fractures. Eight percent of participants had vitamin D deficiency, and 66.0% had secondary hyperparathyroidism. Serum 25(OH)D levels were significantly (P < .001) lower in women with hip fracture than in controls. Multivariate logistic regression analysis adjusted for common risk factors showed that serum 25(OH)D of 20 ng/mL or less was an independent indicator of hip fracture (odds ratio (OR) = 2.98, 95% confidence interval (CI) = 2.11-4.20) and concomitant upper limb fracture in those with existing hip fractures (OR = 4.77, 95% CI = 1.60-10.12). The area under the receiver operating characteristic curve of 25(OH)D was 0.77 (95% CI = 0.68-0.84) for hip fracture and 0.80 (95% CI = 0.72-0.89) for hip and upper limb fractures. Vitamin D insufficiency and secondary hyperparathyroidism were a common problem in postmenopausal women who presented with concomitant hip and upper limb fractures, suggesting that they might contribute to the pathophysiology of fractures in postmenopausal women. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.
Wang, Ching-Yi; Graham, James E; Karmarkar, Amol M; Reistetter, Timothy A; Protas, Elizabeth J; Ottenbacher, Kenneth J
2014-06-01
To assess the utility of functional status in classifying patients by discharge setting after inpatient rehabilitation for hip fracture. Retrospective cohort study. A total of 1257 inpatient rehabilitation facilities in the United States. Medicare beneficiaries (N = 117,168) receiving inpatient rehabilitation for hip fracture from 2007 to 2009. Receiver operating characteristic curve analyses to assess the overall discriminatory ability of functional status scores (Functional Independence Measure [FIM] total, FIM cognition, and FIM motor) and to identify the functioning threshold that best differentiates patients by discharge setting. Discharge setting (community versus institutional). Approximately 68% of patients were discharged to the community after inpatient rehabilitation for hip fracture. Receiver operating characteristic curve analyses indicate that discharge FIM motor ratings (area under the curve: 0.84) alone are as effective as a multivariable model (area under the curve: 0.85), including sociodemographic and clinical factors, in discriminating patients discharged to the community from those discharged to an institution. A discharge FIM motor rating of 58 yielded the best balance in sensitivity and specificity for classifying patients by discharge setting. Discharge FIM motor ratings demonstrated good discriminatory ability for classifying discharge setting. An FIM motor rating of 58 may serve as a clinical tool to guide treatment plans and/or as additional information in complex discharge planning decisions for patients with hip fracture. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
[Effects of Surgically Treated Pelvic Ring and Acetabular Fractures on Postural Control].
Lang, P; Schnegelberger, A; Riesner, H-J; Stuby, F; Friemert, B; Palm, H-G
2016-04-01
The aim of surgical treatment of pelvic ring and acetabular fractures is to allow rapid mobilisation of patients in order to restore stance and gait stability (postural control), as this significantly correlates with a positive outcome. The regulation of postural stability is mainly controlled by transmission of proprioceptive stimuli. In addition, the pelvis serves as a connection between the legs and the spine and thus is also of great importance for mechanical stabilisation. It remains unclear whether surgical treatment of pelvic ring and acetabular fractures affects the regulation of postural control. Therefore, the aim of this study was to examine the impact of surgically treated pelvic ring and acetabular fractures on postural stability by means of computerised dynamic posturography (CDP) after a mean of 35 months and to compare the results with a healthy control group. A retrospective case control study of 38 patients with surgically treated pelvic ring and acetabular fractures and 38 healthy volunteers was carried out using CDP. The average time of follow-up was 35 (12-78) months. The most important outcome parameter in this investigation was the overall stability index (OSI). Hip joint mobility, the health-related quality of life (SF-12) and pain were supplementary outcome parameters. It was found that surgically treated pelvic ring and acetabular fractures had no influence on postural stability. The OSI was 2.1 ° in the patient group and 1.9 ° in the control group. There was no significant difference between the groups in hip joint mobility. A total of 52 % of patients showed no or only mild pain. Mean health-related quality of life was the same as in the total population. Surgically treated pelvic ring and acetabular fractures do not lead to deterioration in postural control in the mid term. This is of high prognostic importance for rapid mobilisation of the patients. Therefore no increase in the risk of falling is expected after successfully treatment of fractures. Georg Thieme Verlag KG Stuttgart · New York.
Another fractured neck of femur: do we need a lateral X-ray?
Almazedi, B; Smith, C D; Morgan, D; Thomas, G; Pereira, G
2011-05-01
This study aimed to define the role of the lateral X-ray in the assessment and treatment planning of proximal femoral fractures. Occult fractures were not included. Radiographs from 359 consecutive patients with proximal femoral fractures admitted to our emergency department over a 12 month period were divided into anteroposterior (AP) views and lateral views. Three blinded reviewers independently assessed the radiographs, first AP views alone then AP plus lateral views, noting the fracture classification for each radiograph. These assessments were then compared with the intra-operative diagnosis, which was used as the gold standard. A 2 × 2 contingency square table was created and Pearson's χ(2) test was used for statistical analysis. The rate of correct classification by the reviewers was improved by the assessment of the lateral X-ray in addition to the AP view for intracapsular fractures (p<0.013) but not for extracapsular fractures (p=0.27). However, the only advantage obtained by assessing the lateral view in intracapsular fractures was the detection of displacement where the fracture appeared undisplaced on the initial AP view. This study provides statistical evidence that one view is adequate and safe for the majority of hip fractures. The lateral radiograph should not be performed routinely in order to make considerable savings in money and time and to avoid unnecessary patient discomfort.
Diabetes, bone and glucose-lowering agents: clinical outcomes.
Schwartz, Ann V
2017-07-01
Older adults with diabetes are at higher risk of fracture and of complications resulting from a fracture. Hence, fracture risk reduction is an important goal in diabetes management. This review is one of a pair discussing the relationship between diabetes, bone and glucose-lowering agents; an accompanying review is provided in this issue of Diabetologia by Beata Lecka-Czernik (DOI 10.1007/s00125-017-4269-4 ). Specifically, this review discusses the challenges of accurate fracture risk assessment in diabetes. Standard tools for risk assessment can be used to predict fracture but clinicians need to be aware of the tendency for the bone mineral density T-score and the fracture risk assessment tool (FRAX) to underestimate risk in those with diabetes. Diabetes duration, complications and poor glycaemic control are useful clinical markers of increased fracture risk. Glucose-lowering agents may also affect fracture risk, independent of their effects on glycaemic control, as seen with the negative skeletal effects of the thiazolidinediones; in this review, the potential effects of glucose-lowering medications on fracture risk are discussed. Finally, the current understanding of effective fracture prevention in older adults with diabetes is reviewed.
Le traitement chirurgical des fractures du cotyle: à propos de 22 cas
Mahdane, Hicham; Elghazi, Amine; Shimi, Mohamed; Elibrahimi, Abdelhalim; Elmrini, Abdelmajid
2014-01-01
Vingt deux patients présentant une fracture incongruente de l'acétabulum ont été opérés et revues avec un recul moyen de 2 ans. Le but de cette étude est d'analyser les résultats fonctionnels et radiologiques des fractures de l'acétabulum après traitement chirurgical. La population était constituée de 17 hommes et 5 femmes, avec un âge moyen de 42,5 ans. Les fractures de l'acétabulum étaient répertoriées selon la classification de Judet et Letournel: 11 fractures de la paroi postérieure, une fracture de la colonne postérieure, six fractures transversales, quatre fractures transversales associées à une paroi postérieure, et une seule fracture de la colonne postérieure avec fracture de la paroi postérieure. Quatre patients présentaient des lésions associées du bassin, sept patients avaient une luxation postérieur de la hanche, deux une luxation centrale et deux avaient un traumatisme crânien associée. Deux voies d'abords ont été utilisées dans ce travail: la voie de Kocher Langenbeck (19 cas), et la voie de Dana Mears (4 cas). A partir du bilan radiologique initial (bassin face, ¾ alaire, ¾ obturateur et tomodensitomértie) on évaluer le déplacement, la congruence, tête/toit et tête/acétabulum ainsi que le degré de comminution. La qualité de réduction était évaluée selon les critères de Matta et les résultats fonctionnels selon la cotation de Merle D'Aubigné. Sur le Plan radiologique nous avons obtenu 56,52% de réduction anatomique, alors que sur le plan fonctionnel 78% patient avaient de bons et très bon résultats. Parmi les complications postopératoires, on a noté un seul cas d'infection cutanée superficielle, cinq ossifications héterotopiques. A distance un cas d'ostéonécrose aseptique de la tête fémorale et un cas de coxarthrose. PMID:25374628
Pain conditions ranked by healthcare costs for members of a national health plan.
Pasquale, Margaret K; Dufour, Robert; Schaaf, David; Reiners, Andrew T; Mardekian, Jack; Joshi, Ashish V; Patel, Nick C
2014-02-01
Healthcare resource utilization (HCRU) and associated costs specific to pain are a growing concern, as increasing dollar amounts are spent on pain-related conditions. Understanding which pain conditions drive the highest utilization and cost burden to the healthcare system would enable providers and payers to better target conditions to manage pain adequately and efficiently. The current study focused on 36 noncancer chronic and 14 noncancer acute pain conditions and measured the HCRU and costs per member over 365 days. These conditions were ranked by per-member costs and total adjusted healthcare costs to determine the most expensive conditions to a national health plan. The top 5 conditions for the commercial line of business were back pain, osteoarthritis (OA), childbirth, injuries, and non-hip, non-spine fractures (adjusted annual total costs for the commercial members were $119 million, $98 million, $69 million, $61 million, and $48 million, respectively). The top 5 conditions for Medicare members were OA, back pain, hip fractures, injuries, and non-hip, non-spine fractures (adjusted annual costs for the Medicare members were $327 million, $218 million, $117 million, $82 million, and $67 million, respectively). The conditions ranked highest for both per-member and total healthcare costs were hip fractures, childbirth, and non-hip, non-spine fractures. Among these, hip fractures in the Medicare member population had the highest mean cost per member (adjusted per-member cost was $21,058). Further examination specific to how pain is managed in these high-cost conditions will enable providers and payers to develop strategies to improve patient outcomes through appropriate pain management. © 2013 Humana Inc. and Pfizer Inc. Pain Practice © 2013 World Institute of Pain.
Survivorship and complications of total hip arthroplasty in patients with dwarfism.
Modi, Ronuk M; Kheir, Michael M; Tan, Timothy L; Penny, Gregory S; Chen, Chi-Lung; Shao, Hongyi; Chen, Antonia F
2017-09-19
Total hip arthroplasty (THA) is a common procedure used to treat bony hip deformities and skeletal dysplasia in dwarfism. These surgeries are often more difficult than conventional THA as they may involve malformed joints and poor bone quality, and may require smaller prostheses. This study aims to investigate whether implant survivorship and revision rates vary among patients with and without dwarfism undergoing THA. A retrospective case-control study was performed for 102 THAs completed between 1997 and 2014 in patients under the height threshold of 147.32 cm. This cohort was matched 1:1.5 with patients of normal height with respect to age, gender, year of surgery, and Charlson comorbidities. All cases had a minimum follow-up of 1 year. A chart review was performed to identify patient and surgical characteristics, including outcomes. Radiographs were assessed for deformity, loosening, and periprosthetic fractures among other factors. The 2-, 5-, and 10-year survivorship of THA in patients with dwarfism was 92.9%, 92.9%, and 80.7%, respectively; and 94.4%, 86.4%, and 86.4% for controls, respectively (p = 0.95). The dwarfism cohort demonstrated an OR of 3.81 and 3.02 for revision for periprosthetic fractures (p = 0.11) and mechanical wear (p = 0.21), respectively. THA in patients with dwarfism achieves comparable results to a non-dwarfism population with regards to implant survivorship; however, there is a trend toward increased periprosthetic fractures and wear-related failures. Surgeons should be aware of this potentially higher risk in this population and take morphological differences into account during surgical planning and technique.
Operative Fixation of Rib Fractures Indications, Techniques, and Outcomes.
Galos, David; Taylor, Benjamin; McLaurin, Toni
2017-01-01
Rib fractures are extremely common injuries and vary in there severity from single nondisplaced fractures to multiple segmental fractures resulting in flail chest and respiratory compromise. Historically, rib fractures have been treated conservatively with pain control and respiratory therapy. However this method may not be the best treatment modality in all situations. Operative fixation of select rib fractures has been increasing in popularity especially in patients with flail chest and respiratory compromise. Newer techniques use muscle sparing approaches and precontoured locking plate technology to obtain stable fixation and allow improved respiration. Current reports shows that rib fracture fixation offers the benefits of improved respiratory mechanics and improved pain control in the severe chest wall injury with resultant improvement in patient outcomes by decreasing time on the ventilator, time in the intensive care unit, and overall hospital length of stay.
Non-linear relationship between serum 25-hydroxyvitamin D concentration and subsequent hip fracture.
de Koning, L; Henne, D; Hemmelgarn, B R; Woods, P; Naugler, C
2013-07-01
Serum 25-OH vitamin D levels were compared in 254 hip fracture subjects and 2,402 matched control subjects. There was a significant inverse association between 25-OH vitamin D and hip fracture only between 0 and 70 nmol/L. Vitamin D is integral to bone metabolism, however the utility of serum 25-OH vitamin D as a risk marker for hip fractures is controversial. We conducted a case-control study of patients admitted to the hospitals with hip fractures in Calgary, Alberta, (catchment population 1.4 million) between January 1, 2007 and August 31, 2011. We searched the laboratory information system of Calgary Laboratory Services for serum 25-OH vitamin D levels within 6 months prior to admission on patients admitted to hospital with hip fractures. Cases were identified through the Calgary Laboratory Services laboratory information system and were matched to controls for age, sex, and month of testing. The hip fracture-25-OH vitamin D association was examined using multiple linear and spline regression. Of 305 subjects initially identified with hip fractures, serum 25-OH vitamin D levels were available for 254 (83 %). These were matched to 2,402 control subjects. We observed a significant (p < 0.01) non-linear relationship such that 25-OH vitamin D was inversely associated with hip fracture only below 70 nmol/L (odds ratio = 0.81 per 10 nmol/L increase; 95 % CI 0.86-0.93). The utility of 25-OH vitamin D level as a risk marker for hip fracture depends on the cut-off level used and was of potential use only for lower levels of 25-OH vitamin D.
Use of acid-suppressive drugs and risk of fracture: a meta-analysis of observational studies.
Eom, Chun-Sick; Park, Sang Min; Myung, Seung-Kwon; Yun, Jae Moon; Ahn, Jeong-Soo
2011-01-01
Previous studies have reported inconsistent findings regarding the association between the use of acid-suppressive drugs such as proton pump inhibitors (PPIs) and histamine 2 receptor antagonists (H(2)RAs) and fracture risk. We investigated this association using meta-analysis. We searched MEDLINE (PubMed), EMBASE, and the Cochrane Library from inception through December 2010 using common key words. We included case-control, nested case-control, and cohort studies. Two evaluators independently reviewed and selected articles. We determined pooled effect estimates by using random-effects meta-analysis, because of heterogeneity. Of 1,809 articles meeting our initial inclusion criteria, 5 case-control studies, 3 nested case-control studies, and 3 cohort studies were included in the final analyses. The pooled odds ratio (OR) for fracture was 1.29 (95% confidence interval [CI], 1.18-1.41) with use of PPIs and 1.10 (95% CI, 0.99-1.23) with use of H(2)RAs when compared with nonuse of the respective medications. Long-term use of PPIs increased the risk of any fracture (adjusted OR = 1.30; 95% CI, 1.15-1.48) and hip fracture risk (adjusted OR = 1.34; 95% CI, 1.09-1.66), whereas long-term H(2)RA use was not significantly associated with fracture risk. We found possible evidence linking PPI use to an increased risk of fracture, but no association between H(2)RA use and fracture risk. Widespread use of PPIs with the potential risk of fracture is of great importance to public health. Clinicians should carefully consider their decision to prescribe PPIs for patients already having an elevated risk of fracture because of age or other factors.
Greater Polar Moment of Inertia at the Tibia in Athletes Who Develop Stress Fractures
Weidauer, Lee A.; Binkley, Teresa; Vukovich, Matt; Specker, Bonny
2014-01-01
Background: Several previous investigations have determined potential risk factors for stress fractures in athletes and military personnel. Purpose: To determine factors associated with the development of stress fractures in female athletes. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 88 female athletes (cross-country, n = 29; soccer, n = 15; swimming, n = 9; track and field, n = 14; volleyball, n = 12; and basketball, n = 9) aged 18 to 24 years were recruited to participate in a longitudinal bone study and had their left distal tibia at the 4%, 20%, and 66% sites scanned by peripheral quantitative computed tomography (pQCT). Patients included 23 athletes who developed stress fractures during the following year (cases). Whole body, hip, and spine scans were obtained using dual-energy x-ray absorptiometry (DXA). Analysis of covariance was used to determine differences in bone parameters between cases and controls after adjusting for height, lower leg length, lean mass, fat mass, and sport. Results: No differences were observed between cases and controls in any of the DXA measurements. Cases had significantly greater unadjusted trabecular bone mineral content (BMC), greater polar moment of inertia (PMI) at the 20% site, and greater cortical BMC at the 66% site; however, after adjusting for covariates, the differences became nonsignificant. When analyses were repeated using all individuals who had ever had a stress fracture as cases (n = 31) and after controlling for covariates, periosteal circumference was greater in the cases than the controls (71.1 ± 0.7 vs 69.4 ± 0.5 mm, respectively; P = .04). Conclusion: A history of stress fractures is associated with larger bones. These findings are important because larger bones were previously reported to be protective against fractures and stress fractures, but study findings indicate that may not always be true. One explanation could be that individuals who sustain stress fractures have greater loading that results in greater periosteal circumference but also results in the development of stress fractures. PMID:26535343
Greater Polar Moment of Inertia at the Tibia in Athletes Who Develop Stress Fractures.
Weidauer, Lee A; Binkley, Teresa; Vukovich, Matt; Specker, Bonny
2014-07-01
Several previous investigations have determined potential risk factors for stress fractures in athletes and military personnel. To determine factors associated with the development of stress fractures in female athletes. Case-control study; Level of evidence, 3. A total of 88 female athletes (cross-country, n = 29; soccer, n = 15; swimming, n = 9; track and field, n = 14; volleyball, n = 12; and basketball, n = 9) aged 18 to 24 years were recruited to participate in a longitudinal bone study and had their left distal tibia at the 4%, 20%, and 66% sites scanned by peripheral quantitative computed tomography (pQCT). Patients included 23 athletes who developed stress fractures during the following year (cases). Whole body, hip, and spine scans were obtained using dual-energy x-ray absorptiometry (DXA). Analysis of covariance was used to determine differences in bone parameters between cases and controls after adjusting for height, lower leg length, lean mass, fat mass, and sport. No differences were observed between cases and controls in any of the DXA measurements. Cases had significantly greater unadjusted trabecular bone mineral content (BMC), greater polar moment of inertia (PMI) at the 20% site, and greater cortical BMC at the 66% site; however, after adjusting for covariates, the differences became nonsignificant. When analyses were repeated using all individuals who had ever had a stress fracture as cases (n = 31) and after controlling for covariates, periosteal circumference was greater in the cases than the controls (71.1 ± 0.7 vs 69.4 ± 0.5 mm, respectively; P = .04). A history of stress fractures is associated with larger bones. These findings are important because larger bones were previously reported to be protective against fractures and stress fractures, but study findings indicate that may not always be true. One explanation could be that individuals who sustain stress fractures have greater loading that results in greater periosteal circumference but also results in the development of stress fractures.
Hip fracture patients in India have vitamin D deficiency and secondary hyperparathyroidism.
Dhanwal, D K; Sahoo, S; Gautam, V K; Saha, R
2013-02-01
This study evaluated the parameters of bone mineral homeostasis including 25(OH)D and PTH in 90 Indian patients with hip fracture and 90 controls. Hypovitaminosis D, secondary hyperparathyroidism, and biochemical osteomalacia was present in 77, 69, and 50 % patients, respectively, significantly higher compared to controls. Vitamin D deficiency is an important risk factor for hip fracture. The prevalence of vitamin D deficiency is not well known in hip fracture patients from India. Therefore, the present study was conducted to evaluate the parameters of bone mineral homeostasis including 25(OH)D and intact PTH in hip fracture from North India. Ninety consecutive patients with hip fracture and similar number of age- and sex-matched controls were enrolled in the study. The fasting venous samples were analyzed for 25-hydroxyvitamin D (25-OHD), intact parathyroid hormone (PTH), alkaline phosphatase (ALP), calcium, and phosphorus. Vitamin D deficiency was defined as serum 25-OHD of <20 ng/dl. The mean age of hip fracture subjects was 65.9 ± 12.6 which was comparable in men and women. Majority of study subjects were women (70 women and 20 men). The serum 25(OH)D and calcium levels were significantly lower, whereas the intact PTH and ALP levels were significantly higher in patients compared to controls. There was significant negative correlation between serum 25(OH)D and PTH. In the hip fracture group, 76.7 % of the subjects had vitamin D deficiency, and 68.9 % had secondary hyperparathyroidism. In the control group, vitamin D deficiency and elevated PTH levels were seen in 32.3 and 42.2 %, respectively. About three fourths of hip fracture patients have vitamin D deficiency, and two thirds have secondary hyperparathyroidism. Therefore, the serum 25-OHD level may be a useful index for the assessment of risk of hip fracture in India.
Jenkins, Thomas; Coutts, Louise V; D'Angelo, Stefania; Dunlop, Douglas G; Oreffo, Richard O C; Cooper, Cyrus; Harvey, Nicholas C; Thurner, Phillipp J
2016-01-01
In contrast to traditional approaches to fracture risk assessment using clinical risk factors and bone mineral density (BMD), a new technique, reference point microindentation (RPI), permits direct assessment of bone quality; in vivo tibial RPI measurements appear to discriminate patients with a fragility fracture from controls. However, it is unclear how this relates to the site of the most clinically devastating fracture, the femoral neck, and whether RPI provides information complementary to that from existing assessments. Femoral neck samples were collected at surgery after low-trauma hip fracture (n = 46; 17 male; aged 83 [interquartile range 77-87] years) and compared, using RPI (Biodent Hfc), with 16 cadaveric control samples, free from bone disease (7 male; aged 65 [IQR 61-74] years). A subset of fracture patients returned for dual-energy X-ray absorptiometry (DXA) assessment (Hologic Discovery) and, for the controls, a micro-computed tomography setup (HMX, Nikon) was used to replicate DXA scans. The indentation depth was greater in femoral neck samples from osteoporotic fracture patients than controls (p < 0.001), which persisted with adjustment for age, sex, body mass index (BMI), and height (p < 0.001) but was site-dependent, being less pronounced in the inferomedial region. RPI demonstrated good discrimination between fracture and controls using receiver-operating characteristic (ROC) analyses (area under the curve [AUC] = 0.79 to 0.89), and a model combining RPI to clinical risk factors or BMD performed better than the individual components (AUC = 0.88 to 0.99). In conclusion, RPI at the femoral neck discriminated fracture cases from controls independent of BMD and traditional risk factors but dependent on location. The clinical RPI device may, therefore, supplement risk assessment and requires testing in prospective cohorts and comparison between the clinically accessible tibia and the femoral neck. © 2015 American Society for Bone and Mineral Research. © 2015 American Society for Bone and Mineral Research.
Majumdar, Sumit R; Beaupre, Lauren A; Harley, Charles H; Hanley, David A; Lier, Douglas A; Juby, Angela G; Maksymowych, Walter P; Cinats, John G; Bell, Neil R; Morrish, Donald W
2007-10-22
Patients who survive hip fracture are at high risk of recurrent fractures, but rates of osteoporosis treatment 1 year after sustaining a fracture are less than 10% to 20%. We have developed an osteoporosis case manager intervention. The case manager educated patients, arranged bone mineral density tests, provided prescriptions, and communicated with primary care physicians. The intervention was compared with usual care in a randomized controlled trial. We recruited from all hospitals that participate in the Capital Health system (Alberta, Canada), including patients 50 years or older who had sustained a hip fracture and excluding those who were receiving osteoporosis treatment or who lived in a long-term care facility. Primary outcome was bisphosphonate therapy 6 months after fracture; secondary outcomes included bone mineral density testing, appropriate care (bone mineral density testing and treatment if bone mass was low), and intervention costs. We screened 2219 patients and allocated 220, as follows: 110 to the intervention group and 110 to the control group. Median age was 74 years, 60% were women, and 37% reported having had previous fractures. Six months after hip fracture, 56 patients in the intervention group (51%) were receiving bisphosphonate therapy compared with 24 patients in the control group (22%) (adjusted odds ratio, 4.7; 95% confidence interval, 2.4-8.9; P < .001). Bone mineral density tests were performed in 88 patients in the intervention group (80%) vs 32 patients in the control group (29%) (P < .001). Of the 120 patients who underwent bone mineral density testing, 25 (21%) had normal bone mass. Patients in the intervention group were more likely to receive appropriate care than were patients in the control group (67% vs 26%; P < .001). The average intervention cost was $50.00 per patient. For a modest cost, a case manager was able to substantially increase rates of osteoporosis treatment in a vulnerable elderly population at high risk of future fractures.
Machado-Duque, Manuel E; Castaño-Montoya, Juan Pablo; Medina-Morales, Diego A; Castro-Rodríguez, Alejandro; González-Montoya, Alexandra; Machado-Alba, Jorge E
2018-03-01
To determine the association between the use of anticholinergic drugs and the risk of falls with hip fracture in a population older than 60 years. A case-control study in patients older than 60 years with a diagnosis of hip fracture. All drugs dispensed during the previous 30 days were identified. Sociodemographic, clinical, pharmacological (drugs according to the Anticholinergic Risk Scale [ARS]), and polypharmacy variables were analyzed. Falls with hip fracture and type of drug according to the ARS. A total of 300 patients with hip fracture and 600 controls were included. The mean age was 81.6 ± 8.9 years, with female predominance (71.3%). The use of drugs with moderate (odds ratio [OR]: 1.97, 95% confidence interval [CI]: 1.19-3.27) or high ARS scores (OR: 1.83, 95% CI: 1.13-2.96) increased the probability of fracture. There was an association between the use of drugs with anticholinergic properties and the probability of hip fracture in elderly patients and it was possible to establish the level of risk.
Impact of a community-based osteoporosis and fall prevention program on fracture incidence.
Grahn Kronhed, Ann-Charlotte; Blomberg, Carina; Karlsson, Nadine; Löfman, Owe; Timpka, Toomas; Möller, Margareta
2005-06-01
Associations between a 10-year community-based osteoporosis and fall prevention program and fracture incidence amongst middle-aged and elderly residents in an intervention community are studied, and comparisons are made with a control community. A health-education program was provided to all residents in the intervention community, which addressed dietary intake, physical activity, smoking habits and environmental risk factors for osteoporosis and falls. Both communities are small, semi-rural and situated in Ostergotland County in southern Sweden. The analysis is based on incidences of forearm fractures in the population 40 years of age or older, and hip fractures in the population 50 years of age or older. Data for three 5-year periods (pre-, early and late intervention) are accumulated and compared. In the intervention community, forearm fracture incidence decreased in women. There are also tendencies towards decreasing forearm fracture incidence in men, and towards decreasing trochanteric hip fracture incidences in women and in men in the late intervention period. No such changes in fracture incidences are found in the control community. Cervical hip fracture incidence did not change in the intervention and the control communities. Although the reported numbers of fractures are small (a total of 451 forearm and 357 hip fractures), the numbers are based on total community populations and thus represent a true difference. The decrease in forearm fracture incidence among women, and the tendency towards decreasing trochanteric hip fractures, in contrast to the absence of change in cervical hip fractures, might be mainly due to a more rapid effect of fall preventive measures than an increase in bone strength in the population. For the younger age groups an expected time lag between intervention and effect might invalidate the short follow-up period for outcome measurements. Thus, the effect of the 10-year intervention program on fracture incidence should be followed during an extended post-intervention period.
Temperament and fracture in preschool-aged children.
Ryckman, Kandace; Richmond, Sarah A; Anderson, Laura N; Birken, Catherine S; Parkin, Patricia C; Macarthur, Colin; Maguire, Jonathon L; Howard, Andrew W
2017-07-01
Approximately one-half of all children will sustain a fracture before adulthood. Understanding the factors that place a child at increased risk of fracture is necessary to inform effective injury prevention strategies. The purpose of this study was to examine the association between temperament and fracture risk in preschool-aged children. Children aged 3 to 6 years who were diagnosed with a fracture were recruited from the Hospital for Sick Children Fracture Clinic. Using a retrospective case-control study design, the 148 cases were frequency-matched by age and sex to 426 controls from the TARGet Kids primary care paediatric cohort. The Childhood Behaviour Questionnaire, a 36-item caregiver response questionnaire was used to assess three of the following temperament factors: surgency (e.g., high activity level), negative affect (e.g., anger, fear, discomfort) and effortful control (e.g., attentional focusing). Unadjusted logistic models demonstrated no association between children with previous fracture and higher scores of surgency (unadjusted odds ratio [OR]=1.06, 95% confidence interval [CI]: 0.84, 1.34), negative affect (unadjusted OR=1.15, 95% CI: 0.93, 1.42) or effortful control (unadjusted OR=0.80, 95% CI: 0.63, 1.03). Further, models adjusted for covariates also demonstrated no significant association with surgency (1.00, 95% CI: 0.78, 1.29), negative affect (1.09, 95% CI: 0.86, 1.37) and effortful control (0.80, 95% CI: 0.61, 1.05). None of the three main temperament types identified by the Childhood Behaviour Questionnaire were associated with an increase in fracture risk.
Vitamin D and Fracture Risk in Early Childhood: A Case-Control Study
Anderson, Laura N.; Heong, Sze Wing; Chen, Yang; Thorpe, Kevin E.; Adeli, Khosrow; Howard, Andrew; Sochett, Etienne; Birken, Catherine S.; Parkin, Patricia C.; Maguire, Jonathon L.; Abdullah, Kawsari; Anderson, Laura N.; Birken, Catherine S.; Borkhoff, Cornelia M.; Carsley, Sarah; Chen, Yang; Katz-Lavigne, Mikael; Kavikondala, Kanthi; Kowal, Christine; Maguire, Jonathon L.; Mason, Dalah; Omand, Jessica; Parkin, Patricia C.; Persaud, Navindra; van den Heuvel, Meta; Baker, Jillian; Barozzino, Tony; Bonifacio, Joey; Campbell, Douglas; Cheema, Sohail; Chisamore, Brian; Danayan, Karoon; Das, Paul; Derocher, Mary Beth; Do, Anh; Dorey, Michael; Freeman, Sloane; Fung, Keewai; Guiang, Charlie; Handford, Curtis; Hatch, Hailey; Jacobson, Sheila; Kiran, Tara; Knowles, Holly; Kwok, Bruce; Lakhoo, Sheila; Lam-Antoniades, Margarita; Lau, Eddy; Leung, Fok-Han; Loo, Jennifer; Mahmoud, Sarah; Moodie, Rosemary; Morinis, Julia; Naymark, Sharon; Neelands, Patricia; Owen, James; Peer, Michael; Perlmutar, Marty; Persaud, Navindra; Pinto, Andrew; Porepa, Michelle; Ramji, Nasreen; Ramji, Noor; Rosenthal, Alana; Saunderson, Janet; Saxena, Rahul; Sgro, Michael; Shepherd, Susan; Smiltnieks, Barbara; Taylor, Carolyn; Weisdors, Thea; Wijayasinghe, Sheila; Wong, Peter; Ying, Ethel; Young, Elizabeth
2017-01-01
Abstract The objective of this study was to evaluate the association of vitamin D intake and serum levels with fracture risk in children under 6 years of age. A case-control study was conducted in Toronto, Ontario, Canada. Cases were recruited from the fracture clinic at the Hospital for Sick Children, and matched controls were obtained from the TARGet Kids! primary-care research network. Controls were matched to cases on age, sex, height, and season. Fracture risk was estimated from conditional logistic regression, with adjustment for skin type, fracture history, waist circumference, outdoor free play, neighborhood income, soda consumption, and child's birth weight. A total of 206 cases were recruited during May 2009–April 2013 and matched to 343 controls. Serum 25-hydroxyvitamin D concentration (per 10-nmol/L increment: adjusted odds ratio (aOR) = 0.95, 95% confidence interval (CI): 0.88, 1.03) and intake of cow's milk (<2 cups/day vs. 2 cups/day: aOR = 0.95 (95% CI: 0.60, 1.52); >2 cups/day vs. 2 cups/day: aOR = 1.39 (95% CI: 0.85, 2.23)) were not significantly associated with reduced odds of fracture. A statistically significant association was observed between child use of vitamin D supplements and decreased odds of fracture (yes vs. no: aOR = 0.42, 95% CI: 0.25, 0.69). Vitamin D supplementation, but not serum 25-hydroxyvitamin D level or milk intake, was associated with reduced fracture risk among these healthy young children. PMID:28459987
Bi, Hong-zheng; Yang, Mao-qing; Tan, Yuan-chao; Fu, Song
2008-07-01
To study the curative effect and safety of rotatory manual reduction with forceps holder and retrograde percutaneous pinning transfixation in treating clavicular fracture. All 201 cases of clavicular fractures were randomly divided into treatment group (101 cases) and control group (100 cases). The treatment group was treated by rotatory manual reduction with forceps holder and retrograde percutaneous pinning transfixation. The control group was treated by open reduction and internal fixation with Kirschner pin. All cases were followed up for 4 to 21 months (mean 10.6 months). SPSS was used to analyze clinic healing time of fracture and shoulder-joint function in both two groups. After operation, 101 cases of treatment group achieved union of fracture and the clinical healing time was 28 to 49 days (mean 34.5+/-2.7 days). In control group,there were 4 cases with nonunion of fracture,the other 96 cases were union,the clinical healing time was 36 to 92 days (mean 55.3+/-4.8 days). The excellent and good rate of shoulder-joint function was 100% in treatment group and 83% in control group. By t-test and chi2-test, there was significant difference between the two groups in curative effect (P<0.05). Rotatory manual reduction with forceps holder and retrograde pinning transfixation can be used in various kinds of clavicular shaft fracture, with many virtues such as easy operation, reliable fixation, short union time of fracture, good functional recovery of shoulder-joint and no incision scar affecting appearance.
Naumann, Michael; Sterzenbach, Guido; Dietrich, Thomas; Bitter, Kerstin; Frankenberger, Roland; von Stein-Lausnitz, Manja
2017-11-01
This is the first long-term randomized controlled trial to evaluate dentin-like glass fiber posts (GFPs) compared with rather rigid titanium posts (TPs) for post-endodontic restoration of severely damaged endodontically treated teeth with 2 or fewer remaining cavity walls. Ninety-one subjects in need of post-endodontic restorations were randomly assigned to receive either a tapered GFP (n = 45) or TP (n = 46). Posts were adhesively luted by using self-adhesive resin cement, followed by composite core build-up and preparation of 2-mm ferrule design. Primary end point was loss of restoration for any reason. Kaplan-Meier curves were constructed, and log-rank test was calculated (P < .05). After a follow-up of 132 months, 17 GFP and 20 TP restorations survived, and 19 failed (12 GFP, 7 TP). Failure modes for GFP were root fracture (n = 4), core fracture (n = 1), secondary caries (n = 1), endodontic failure (n = 2), extraction because of tooth mobility grade III associated with insufficient design of removable partial denture (n = 1), tooth fracture (n = 1), and changes in treatment plan (n = 2); failure modes for TP were endodontic failure (n = 5), root fracture (n = 1), and 1 extraction for other reasons. Cumulative survival probability was 58.7% for GFP and 74.2% for TP. When using self-adhesively luted prefabricated posts, resin composite core build-up, and 2-mm ferrule to reconstruct severely damaged endodontically treated teeth, tooth survival is not influenced by post rigidity. Survival decreased rapidly after 8 years of observation in both groups. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Tung, P. P. (Editor); Agrawal, S. P.; Kumar, A.; Katcher, M.
1981-01-01
Papers are presented on the application of fracture mechanics to spacecraft design, fracture control applications on the Space Shuttle reaction control thrusters, and an assessment of fatigue crack growth rate relationships for metallic airframe materials. Also considered are fracture mechanisms and microstructural relationships in Ni-base alloy systems, the use of surface deformation markings to determine crack propagation directions, case histories of metallurgical failures in the electronics industry, and a failure analysis of silica phenolic nozzle liners.
The yerba mate intake has a neutral effect on bone: A case-control study in postmenopausal women.
da Veiga, Denise T A; Bringhenti, Raísa; Bolignon, Aline A; Tatsh, Etiane; Moresco, Rafael N; Comim, Fabio V; Premaor, Melissa O
2018-01-01
Nutritional factors have been associated with osteoporosis and fractures. The intake of coffee may increase the risk of fracture whereas the intake of black and green tea is associated with its reduction. Recently, consumption of yerba mate was associated with increased bone mineral density in postmenopausal women. Nonetheless, its influence on fracture is not known. The aim of this study was to evaluate the effect of yerba mate tea intake on fractures, bone markers, calcium homeostasis, and oxidative stress in postmenopausal women. A case-control study was carried out in South Brazil, 46 women with fractures and 49 controls completed the study. There was no significant difference between the frequency of fractures in women who drank mate tea and women who did not (48.3% vs. 48.5%, p = .99). Moreover, there was no significant difference concerning the serum levels of total calcium, phosphorus, PTH, vitamin D, P1NP, and CTX in the subjects with the history of yerba mate use when compared to controls. Higher serum levels of NOx were found in women who drank the yerba mate infusion. In conclusion, the yerba mate intake is not associated with fracture, and it appears to have a neutral effect on the bone metabolism. Copyright © 2017 John Wiley & Sons, Ltd.
Shepstone, L; Fordham, R; Lenaghan, E; Harvey, I; Cooper, C; Gittoes, N; Heawood, A; Peters, T J; O'Neill, T; Torgerson, D; Holland, R; Howe, A; Marshall, T; Kanis, J A; McCloskey, E
2012-10-01
SCOOP is a UK seven-centre, pragmatic, randomised controlled trial with 5-year follow-up, including 11,580 women aged 70 to 85 years, to assess the effectiveness and cost-effectiveness of a community-based screening programme to reduce fractures. It utilises the FRAX algorithm and DXA to assess the 10-year probability of fracture. Introduction Osteoporotic, or low-trauma, fractures present a considerable burden to the National Health Service and have major adverse effects on quality of life, disability and mortality for the individual. Methods Given the availability of efficacious treatments and a risk assessment tool based upon clinical risk factors and bone mineral density, a case exists to undertake a community-based controlled evaluation of screening for subjects at high risk of fracture, under the hypothesis that such a screening programme would reduce fractures in this population. Results This study is a UK seven-centre, unblinded, pragmatic, randomised controlled trial with a 5-year follow-up period. A total of 11,580 women, aged 70 to 85 years and not on prescribed bone protective therapy will be consented to the trial by post via primary care providing 90% power to detect an 18% decrease in fractures. Conclusions Participants will be randomised to either a screening arm or control. Those undergoing screening will have a 10-year fracture probability computed from baseline risk factors together with bone mineral density measured by DXA in selected subjects. Individuals above an age-dependent threshold of fracture probability will be recommended for treatment for the duration of the trial. Subjects in the control arm will receive 'usual care'. Participants will be followed up 6 months after randomisation and annually by postal questionnaires with independent checking of hospital and primary care records. The primary outcome will be the proportion of individuals sustaining fractures in each group. An economic analysis will be carried out to assess cost-effectiveness of screening. A qualitative evaluation will be conducted to examine the acceptability of the process to participants.
Patterns of Maxillofacial Fractures in Uttar Pradesh, India
Agarwal, Padmanidhi; Mehrotra, Divya; Agarwal, Rajul; Kumar, Sumit; Pandey, Rahul
2016-01-01
This study aimed to obtain dependable epidemiologic data of the variation in cause and characteristics of maxillofacial fractures by identifying, describing, and quantifying trauma. This retrospective study was conducted in the state of Uttar Pradesh, India, over 1 year, based on a systematic computer-assisted database search from March 2015 to March 2016 for maxillofacial fractures. The demographics, etiology, geographic distribution, date of injury, site and number of fractures, and type of intervention were recorded for each. The study population consisted of 1,000 patients with 1,543 fractures. The male:female ratio was 8:1. A peak incidence of fractures was seen in the third decade (mean age: 30.3) with maximum patients younger than 40 years (80.8%). The incidence of fractures was highest in spring (42.9%). Road traffic accidents were the most common cause of trauma (64.4%) and mainly involved two wheelers (60.2%). Single-site fractures were most common. Mostly zygomatic (45.1%) and mandibular fractures (44.4%) were encountered, accounting for approximately 90% of all fractures. The main site of mandibular fractures was the body (34.4%); 46.2% of fractures underwent open reduction and internal fixation (ORIF) while 53.8% were treated by closed methods. The study provides important data to contrive future plans for injury prevention. The trend of most traffic-related injuries continues with the increasing traffic on roads. Zygomatic complex and mandibular fractures remain the most frequent. The major populations at risk are young men and those driving two wheelers. The use of helmets could achieve a large reduction in maxillofacial fractures. Awareness for preventive measures and safety guidelines should be propagated and legislation on traffic rules strictly reinforced. PMID:28210408
Lower limb stress fractures in sport: Optimising their management and outcome
Robertson, Greg A J; Wood, Alexander M
2017-01-01
Stress fractures in sport are becoming increasing more common, comprising up to 10% of all of sporting injuries. Around 90% of such injuries are located in the lower limb. This articles aims to define the optimal management of lower limb stress fractures in the athlete, with a view to maximise return rates and minimise return times to sport. Treatment planning of this condition is specific to the location of the injury. However, there remains a clear division of stress fractures by “high” and “low” risk. “Low risk” stress fractures are those with a low probability of fracture propagation, delayed union, or non-union, and so can be managed reliably with rest and exercise limitation. These include stress fractures of the Postero-Medial Tibial Diaphysis, Metatarsal Shafts, Distal Fibula, Medial Femoral Neck, Femoral Shaft and Calcaneus. “High risk” stress fractures, in contrast, have increased rates of fracture propagation, displacement, delayed and non-union, and so require immediate cessation of activity, with orthopaedic referral, to assess the need for surgical intervention. These include stress fractures of the Anterior Tibial Diaphysis, Fifth Metatarsal Base, Medial Malleolus, Lateral Femoral Neck, Tarsal Navicular and Great Toe Sesamoids. In order to establish the optimal methods for managing these injuries, we present and review the current evidence which guides the treatment of stress fractures in athletes. From this, we note an increased role for surgical management of certain high risk stress fractures to improve return times and rates to sport. Following this, key recommendations are provided for the management of the common stress fracture types seen in the athlete. Five case reports are also presented to illustrate the application of sport-focussed lower limb stress fracture treatment in the clinical setting. PMID:28361017
Davis, Sarah; Martyn-St James, Marrissa; Sanderson, Jean; Stevens, John; Goka, Edward; Rawdin, Andrew; Sadler, Susi; Wong, Ruth; Campbell, Fiona; Stevenson, Matt; Strong, Mark; Selby, Peter; Gittoes, Neil
2016-10-01
Fragility fractures are fractures that result from mechanical forces that would not ordinarily result in fracture. To evaluate the clinical effectiveness and safety of bisphosphonates [alendronic acid (Fosamax ® and Fosamax ® Once Weekly, Merck Sharp & Dohme Ltd), risedronic acid (Actonel ® and Actonel Once a Week ® , Warner Chilcott UK Ltd), ibandronic acid (Bonviva ® , Roche Products Ltd) and zoledronic acid (Aclasta ® , Novartis Pharmaceuticals UK Ltd)] for the prevention of fragility fracture and to assess their cost-effectiveness at varying levels of fracture risk. For the clinical effectiveness review, six electronic databases and two trial registries were searched: MEDLINE, EMBASE, The Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, Web of Science and BIOSIS Previews, Clinicaltrials.gov and World Health Organization International Clinical Trials Registry Platform. Searches were limited by date from 2008 until September 2014. A systematic review and network meta-analysis (NMA) of effectiveness studies were conducted. A review of published economic analyses was undertaken and a de novo health economic model was constructed. Discrete event simulation was used to estimate lifetime costs and quality-adjusted life-years (QALYs) for each bisphosphonate treatment strategy and a strategy of no treatment for a simulated cohort of patients with heterogeneous characteristics. The model was populated with effectiveness evidence from the systematic review and NMA. All other parameters were estimated from published sources. A NHS and Personal Social Services perspective was taken, and costs and benefits were discounted at 3.5% per annum. Fracture risk was estimated from patient characteristics using the QFracture ® (QFracture-2012 open source revision 38, Clinrisk Ltd, Leeds, UK) and FRAX ® (web version 3.9, University of Sheffield, Sheffield, UK) tools. The relationship between fracture risk and incremental net benefit (INB) was estimated using non-parametric regression. Probabilistic sensitivity analysis (PSA) and scenario analyses were used to assess uncertainty. Forty-six randomised controlled trials (RCTs) were included in the clinical effectiveness systematic review, with 27 RCTs providing data for the fracture NMA and 35 RCTs providing data for the femoral neck bone mineral density (BMD) NMA. All treatments had beneficial effects on fractures versus placebo, with hazard ratios varying from 0.41 to 0.92 depending on treatment and fracture type. The effects on vertebral fractures and percentage change in BMD were statistically significant for all treatments. There was no evidence of a difference in effect on fractures between bisphosphonates. A statistically significant difference in the incidence of influenza-like symptoms was identified from the RCTs for zoledronic acid compared with placebo. Reviews of observational studies suggest that upper gastrointestinal symptoms are frequently reported in the first month of oral bisphosphonate treatment, but pooled analyses of placebo-controlled trials found no statistically significant difference. A strategy of no treatment was estimated to have the maximum INB for patients with a 10-year QFracture risk under 1.5%, whereas oral bisphosphonates provided maximum INB at higher levels of risk. However, the PSA suggested that there is considerable uncertainty regarding whether or not no treatment is the optimal strategy until the QFracture score is around 5.5%. In the model using FRAX, the mean INBs were positive for all oral bisphosphonate treatments across all risk categories. Intravenous bisphosphonates were estimated to have lower INBs than oral bisphosphonates across all levels of fracture risk when estimated using either QFracture or FRAX. We assumed that all treatment strategies are viable alternatives across the whole population. Bisphosphonates are effective in preventing fragility fractures. However, the benefit-to-risk ratio in the lowest-risk patients may be debatable given the low absolute QALY gains and the potential for adverse events. We plan to extend the analysis to include non-bisphosphonate therapies. This study is registered as PROSPERO CRD42013006883. The National Institute for Health Research Health Technology Assessment programme.
Fernandez, Carlos A.; Heldebrant, David J.; Bonneville, Alain H. R.; Jung, Hun Bok; Carroll, Kenneth
2016-09-20
An electrophilic acid gas-reactive fracturing and recovery fluid, proppant, and process are detailed. The fluid expands in volume to provide rapid and controlled increases in pressure that enhances fracturing in subterranean bedrock for recovery of energy-producing materials. Proppants stabilize openings in fractures and fissures following fracturing.
Spatially offset raman spectroscopy for non-invasive assessment of fracture healing
NASA Astrophysics Data System (ADS)
Ding, Hao; Lu, Guijin; West, Christopher; Gogola, Gloria; Kellam, James; Ambrose, Catherine; Bi, Xiaohong
2016-02-01
Fracture non-unions and bone re-fracture are common challenges for post-fracture management. To achieve better prognosis and treatment evaluation, it is important to be able to assess the quality of callus over the time course of healing. This study evaluated the potential of spatially offset Raman spectroscopy for assessing the fracture healing process in situ. We investigated a rat model of fracture healing at two weeks and 4 weeks post fracture with a fractured femur and a contralateral control in each animal. Raman spectra were collected from the depilated thighs on both sides transcutaneously in situ with various source/detection offsets. Bone signals were recovered from SORS spectra, and then compared with those collected from bare bones. The relative intensity of mineral from fractured bone was markedly decreased compared to the control. The fractured bones demonstrated lower mineral and carbonate level and higher collagen content in the callus at the early time point. Compared to week 2, collagen mineralization and mineral carbonation increased at 4 weeks post fracture. Similarly, the material properties of callus determined by reference point indentation also increased in the 4-week group, indicating improved callus quality with time. The results from Raman analysis are in agreement with radiographic and material testing, indicating the potential of this technique in assessing fracture healing in vivo.
Seismic Characterizations of Fractures: Dynamic Diagnostics
NASA Astrophysics Data System (ADS)
Pyrak-Nolte, L. J.
2017-12-01
Fracture geometry controls fluid flow in a fracture, affects mechanical stability and influences energy partitioning that affects wave scattering. Our ability to detect and monitor fracture evolution is controlled by the frequency of the signal used to probe a fracture system, i.e. frequency selects the scales. No matter the frequency chosen, some set of discontinuities will be optimal for detection because different wavelengths sample different subsets of fractures. The select subset of fractures is based on the stiffness of the fractures which in turn is linked to fluid flow. A goal is obtaining information from scales outside the optimal detection regime. Fracture geometry trajectories are a potential approach to drive a fracture system across observation scales, i.e. moving systems between effective medium and scattering regimes. Dynamic trajectories (such as perturbing stress, fluid pressure, chemical alteration, etc.) can be used to perturb fracture geometry to enhance scattering or give rise to discrete modes that are intimately related to the micro-structural evolution of a fracture. However, identification of these signal features will require methods for identifying these micro-structural signatures in complicated scattered fields. Acknowledgment: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Geosciences Research Program under Award Number (DE-FG02-09ER16022).
[Petrous bone fracture. Our experience: 1999-2004].
Ramírez Sabio, J B; de Paula Vernetta, C; García Sanchís, J M; Callejo García, F J; Cortés Andrés, O; Quilis Quesada, V; Dualde Beltrán, D; Marco Algarra, J
2006-12-01
To review the petrous bone fractures during the last five years (1999-2004) in our hospital, its manage, control, and analysis onf the associated factors. To analyse the managing protocoles and current bibliography. We review 266 temporal bone fractures, 74 with petrous bone association. We analyse these fractures by sex distribution, injurie severity, otorhinolaryngological clinical findings, production mechanism and radiological findings. The cases are discussed and compared with current bibliography. Petrous bone fractures must be always suspected in patients with head trauma, specially if it associates severity and otorrhagia. It is necessary a deep colaboration between neurosurgeons, radiologists and otorhinolaryngologists to obtain a good management, control and follow up of the patients.
Roussy, J-P; Bessette, L; Bernatsky, S; Rahme, E; Lachaine, J
2013-09-01
Prevention of bone mineral density loss in rheumatoid arthritis (RA) has been associated with use of biologic disease-modifying anti-rheumatic drugs (DMARDs). However, in this study, we could not demonstrate a reduction in the risk of non-vertebral fractures. Additional research is required to clarify the impact of biologic DMARDs on fracture risk in RA. Small studies have suggested biologic DMARDs preserve bone mineral density at 6-12 months. Our objective was to determine the association between biologic DMARD use and the risk of non-vertebral osteoporotic fractures in RA subjects aged ≥50 years. A nested case-control study was conducted using Quebec physician billing and hospital discharge data. RA subjects were identified from International Classification of Disease-9/10 codes in billing and hospitalisation data and followed from cohort entry until the earliest of non-vertebral osteoporotic fracture, death, or end of study period. Controls were matched to cases (4:1 ratio) on age, sex, and date of cohort entry. Biologic DMARD exposure was defined as being on treatment for ≥180 days pre-fracture (index). Conditional logistic regression was used, adjusting for indicators of RA severity, comorbidity, drugs influencing fracture risk, and measures of health care utilisation. Over the study period, 1,515 cases were identified (6,023 controls). The most frequent fracture site was hip/femur (42.3%). In total, 172 subjects (49 cases and 123 controls) were exposed to biologic DMARDs. The median duration of exposure was 735 (interquartile range (IQR), 564) and 645 (IQR, 903) days in cases and controls, respectively. We were unable to demonstrate an association between biologic DMARDs and fracture risk (odds ratio, 1.03; 95% confidence interval, 0.42-2.53). RA duration significantly increased the fracture risk. Despite the positive impact of biologic DMARDs on bone remodelling observed in small studies, we were unable to demonstrate a reduction in the risk of non-vertebral osteoporotic fractures in older adults with RA.
Usala, Rachel L; Fernandez, Stephen J; Mete, Mihriye; Cowen, Laura; Shara, Nawar M; Barsony, Julianna; Verbalis, Joseph G
2015-08-01
The significance of studies suggesting an increased risk of bone fragility fractures with hyponatremia through mechanisms of induced bone loss and increased falls has not been demonstrated in large patient populations with different types of hyponatremia. This matched case-control study evaluated the effect of hyponatremia on osteoporosis and fragility fractures in a patient population of more than 2.9 million. Osteoporosis (n = 30 517) and fragility fracture (n = 46 256) cases from the MedStar Health database were matched on age, sex, race, and patient record length with controls without osteoporosis (n = 30 517) and without fragility fractures (n = 46 256), respectively. Cases without matched controls or serum sodium (Na(+)) data or with Na(+) with a same-day blood glucose greater than 200 mg/dL were excluded. Incidence of diagnosis of osteoporosis and fragility fractures of the upper or lower extremity, pelvis, and vertebrae were the outcome measures. Multivariate conditional logistic regression models demonstrated that hyponatremia was associated with osteoporosis and/or fragility fractures, including chronic [osteoporosis: odds ratio (OR) 3.97, 95% confidence interval (CI) 3.59-4.39; fracture: OR 4.61, 95% CI 4.15-5.11], recent (osteoporosis: OR 3.06, 95% CI 2.81-3.33; fracture: OR 3.05, 95% CI 2.83-3.29), and combined chronic and recent hyponatremia (osteoporosis: OR 12.09, 95% CI 9.34-15.66; fracture: OR 11.21, 95% CI 8.81-14.26). Odds of osteoporosis or fragility fracture increased incrementally with categorical decrease in median serum Na(+). These analyses support the hypothesis that hyponatremia is a risk factor for osteoporosis and fracture. Additional studies are required to evaluate whether correction of hyponatremia will improve patient outcomes.
Controls on fracture distribution in the Giddings Austin Chalk
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wagner, D.T.
1990-09-01
Fracture distribution in the Giddings Austin Chalk is controlled by both structure and the stratigraphy of the Austin Group. Parameters that most affect reservoir performance include fracture width, height, and spacing, as well as the number of fracture sets and their orientations. Lateral variance of these parameters is a function of structural position, while vertical change is related to stratigraphy. The Austin Chalk productive trend is thought to coincide with the hingeline of the Gulf Coast basin, where extension has been concentrated during subsidence of the basin. Fracturing is attributed to a number of mechanisms including normal faulting, bending overmore » buried structures, gravity creep, differential compaction, and aquathermal pressuring. A change in structural style from faulting to flexure takes place from west to east across the Giddings field, accompanied by a change in fracture distribution. In the west, fractures develop only in close proximity to faults whereas in the east they are more widely distributed over broad warps. Stratigraphic controls include lithology, porosity, bed thickness, and ductility contrast between adjacent beds. The Austin Chalk consists of sparse biomicrite interbedded with marls, shales, and clay seams. In general, thin beds are more highly fractured than thick beds, and clean limestone is more highly fractured than marl or shale. Where the more ductile marls and clays exceed a critical thickness, fractures tend to terminate within individual chalk beds, resulting in barriers to vertical flow within the reservoir.« less
NASA Astrophysics Data System (ADS)
Gehne, Stephan; Benson, Philip; Koor, Nick; Enfield, Mark
2017-04-01
The finding of considerable volumes of hydrocarbon resources within tight sedimentary rock formations in the UK led to focused attention on the fundamental fracture properties of low permeability rock types and hydraulic fracturing. Despite much research in these fields, there remains a scarcity of available experimental data concerning the fracture mechanics of fluid driven fracturing and the fracture properties of anisotropic, low permeability rock types. In this study, hydraulic fracturing is simulated in a controlled laboratory environment to track fracture nucleation (location) and propagation (velocity) in space and time and assess how environmental factors and rock properties influence the fracture process and the developing fracture network. Here we report data on employing fluid overpressure to generate a permeable network of micro tensile fractures in a highly anisotropic shale ( 50% P-wave velocity anisotropy). Experiments are carried out in a triaxial deformation apparatus using cylindrical samples. The bedding planes are orientated either parallel or normal to the major principal stress direction (σ1). A newly developed technique, using a steel guide arrangement to direct pressurised fluid into a sealed section of an axially drilled conduit, allows the pore fluid to contact the rock directly and to initiate tensile fractures from the pre-defined zone inside the sample. Acoustic Emission location is used to record and map the nucleation and development of the micro-fracture network. Indirect tensile strength measurements at atmospheric pressure show a high tensile strength anisotropy ( 60%) of the shale. Depending on the relative bedding orientation within the stress field, we find that fluid induced fractures in the sample propagate in two of the three principal fracture orientations: Divider and Short-Transverse. The fracture progresses parallel to the bedding plane (Short-Transverse orientation) if the bedding plane is aligned (parallel) with the direction of σ1. Conversely, the crack plane develops perpendicular to the bedding plane, if the bedding plane is orientated normal to σ1. Fracture initiation pressures are higher in the Divider orientation ( 24MPa) than in the Short-Transverse orientation ( 14MPa) showing a tensile strength anisotropy ( 42%) comparable to ambient tensile strength results. We then use X-Ray Computed Tomography (CT) 3D-images to evaluate the evolved fracture network in terms of fracture pattern, aperture and post-test water permeability. For both fracture orientations, very fine, axial fractures evolve over the entire length of the sample. For the fracturing in the Divider orientation, it has been observed, that in some cases, secondary fractures are branching of the main fracture. Test data from fluid driven fracturing experiments suggest that fracture pattern, fracture propagation trajectories and fracturing fluid pressure (initiation and propagation pressure) are predominantly controlled by the interaction between the anisotropic mechanical properties of the shale and the anisotropic stress environment. The orientation of inherent rock anisotropy relative to the principal stress directions seems to be the main control on fracture orientation and required fracturing pressure.
NASA Astrophysics Data System (ADS)
Sidborn, M.; Neretnieks, I.
2008-08-01
Processes that control the redox conditions in deep groundwaters have been studied. The understanding of such processes in a long-term perspective is important for the safety assessment of a deep geological repository for high-level nuclear waste. An oxidising environment at the depth of the repository would increase the solubility and mobility of many radionuclides, and increase the potential risk for radioactive contamination at the ground surface. Proposed repository concepts also include engineered barriers such as copper canisters, the corrosion of which increases considerably in an oxidising environment compared to prevailing reducing conditions. Swedish granitic rocks are typically relatively sparsely fractured and are best treated as a dual-porosity medium with fast flowing channels through fractures in the rock with a surrounding porous matrix, the pores of which are accessible from the fracture by diffusive transport. Highly simplified problems have been explored with the aim to gain understanding of the underlying transport processes, thermodynamics and chemical reaction kinetics. The degree of complexity is increased successively, and mechanisms and processes identified as of key importance are included in a model framework. For highly complex models, analytical expressions are not fully capable of describing the processes involved, and in such cases the solutions are obtained by numerical calculations. Deep in the rock the main source for reducing capacity is identified as reducing minerals. Such minerals are found inside the porous rock matrix and as infill particles or coatings in fractures in the rock. The model formulation also allows for different flow modes such as flow along discrete fractures in sparsely fractured rocks and along flowpaths in a fracture network. The scavenging of oxygen is exemplified for these cases as well as for more comprehensive applications, including glaciation considerations. Results show that chemical reaction kinetics control the scavenging of oxygen during a relatively short time with respect to the lifetime of the repository. For longer times the scavenging of oxygen is controlled by transport processes in the porous rock matrix. The penetration depth of oxygen along the flowpath depends largely on the hydraulic properties, which may vary significantly between different locations and situations. The results indicate that oxygen, in the absence of easily degradable organic matter, may reach long distances along a flow path during the life-time of the repository (hundreds to thousands of metres in a million years depending on e.g. hydraulic properties of the flow path and the availability of reducing capacity). However, large uncertainties regarding key input parameters exist leading to the conclusion that the results from the model must be treated with caution pending more accurate and validated data. Ongoing and planned experiments are expected to reduce these uncertainties, which are required in order to make more reliable predictions for a safety assessment of a nuclear waste repository.
My Experience as a Foot and Ankle Trauma Surgeon in Montreal, Canada: What's Not in the Books.
Leduc, Stéphane; Nault, Marie-Lyne; Rouleau, Dominique M; Hebert-Davies, Jonah
2016-06-01
Foot and ankle fractures are sometimes seen as routine and easy to treat. However, many fractures vary from typical patterns and require more complex management. Obtaining good outcomes in these situations can be challenging. Often, the difference between average and good results has to do with preoperative planning and good surgical technique. This article outlines numerous techniques and tricks that are not always mentioned in classic textbooks. It focuses on ankle, talus, calcaneus, and midfoot fractures, and discusses numerous techniques and aids to avoid potential problems that may be encountered intraoperatively. Copyright © 2016 Elsevier Inc. All rights reserved.
Kristoffersen, M; Hetzel, U; Parkin, T D H; Singer, E R
2010-01-01
To investigate whether microfractures and alterations in the trabecular bone area are associated with catastrophic bi-axial proximal sesamoid bone fractures (PSBF). Proximal sesamoid bones (PSB) from 10 racehorses with PSBF and from 10 control racehorses without musculoskeletal injury were examined using the bulk basic fuchsin method. Bone histomorphometric and microfracture analysis was performed, and cases and controls compared using two-sample t-test, paired t-test, and Mann-Whitney U test. There was no significant difference in the microfracture density and the trabecular bone area between bones from case and control horses, and between fractured and non-fractured bones in case horses. Microfracture density was low in the areas of the PSB examined. Microfracture density was not significantly different between groups, indicating that propagation of micro-cracks is an unlikely predisposing pathologic alteration in PSBF in British racehorses. There was no significant difference in the bone surface area between groups, which one would expect if modelling, adaptation and an increase in bone density were associated with PSBF fracture in the case horses. Therefore, PSBF in the British racehorse does not appear to be associated with microfractures of the trabecular bone of the PSB. The PSB fractures might represent an acute monotonic fracture; however, the aetiology of the fractures remains unknown with additional research required.
LaCroix, Andrea Z; Jackson, Rebecca D; Aragaki, Aaron; Kooperberg, Charles; Cauley, Jane A; Chen, Zhao; Leboff, Meryl S; Duggan, David; Wactawski-Wende, Jean
2013-10-01
The osteoprotogerin/receptor activator of NF-kappa β/receptor activator of NF-kappa β ligand (OPG/RANK/RANKL) pathway plays a critical role in bone remodeling. This study investigated associations between serum levels of OPG, soluble RANKL (sRANKL), and the ratio of OPG/sRANKL to risk of incident hip fracture. A nested case-control study was conducted among postmenopausal, Caucasian women aged 50-79 at baseline (1993-1998), followed for hip fracture through March 2005 in the Women's Health Initiative Observational Study. 400 incident hip fracture cases were selected and individually matched to 400 controls with no prior fracture or incident hip fracture. Matching factors were baseline age, enrollment date and hormone therapy (HT) exposure. Baseline serum OPG and sRANKL levels were measured using high sensitivity ELISA. Odds ratios were computed for quartiles of each biomarker adjusting for matching factors and hip fracture risk factors. Serum OPG was significantly associated with older age, low physical activity and poorer physical function in control women. sRANKL was inversely associated with total calcium intake in control women, but not associated with age or other fracture risk factors. The odds ratio for hip fracture comparing the highest to lowest quartiles of OPG was 2.28 (95% confidence interval (CI), 1.45-3.61) after adjusting for the matching variables (p-value for linear trend <0.001), and 1.87 (95% CI, 1.15-3.04; p for linear trend=0.02) after adjusting for self-rated health status, physical activity and physical functioning. No significant associations between sRANKL or the ratio of OPG/sRANKL and hip fracture risk were observed. Serum OPG levels were independently associated with a nearly twofold increased risk of hip fracture in postmenopausal women. Copyright © 2013 Elsevier Inc. All rights reserved.
LaCroix, Andrea Z.; Jackson, Rebecca D.; Aragaki, Aaron; Kooperberg, Charles; Cauley, Jane A.; Chen, Zhao; LeBoff, Meryl S.; Duggan, David; Wactawski-Wende, Jean
2013-01-01
Purpose The osteoprotogerin/receptor activator of NF-kappa β/receptor activator of NF-kappa β ligand (OPG/RANK/RANKL) pathway plays a critical role in bone remodeling. This study investigated associations between serum levels of OPG, soluble RANKL (sRANKL), and the ratio of OPG/sRANKL to risk of incident hip fracture. Methods A nested case–control study was conducted among postmenopausal, Caucasian women aged 50–79 at baseline (1993–1998), followed for hip fracture through March 2005 in the Women's Health Initiative Observational Study. 400 incident hip fracture cases were selected and individually matched to 400 controls with noprior fracture or incident hip fracture. Matching factors were baseline age, enrollment date and hormone therapy (HT) exposure. Baseline serum OPG and sRANKL levels were measured using high sensitivity ELISA. Odds ratios were computed for quartiles of each biomarker adjusting for matching factors and hip fracture risk factors. Results Serum OPG was significantly associated with older age, low physical activity and poorer physical function in control women. sRANKL was inversely associated with total calcium intake in control women, but not associated with age or other fracture risk factors. The odds ratio for hip fracture comparing the highest to lowest quartiles of OPG was 2.28 (95% confidence interval (CI), 1.45–3.61) after adjusting for the matching variables (p-value for linear trend <0.001), and 1.87 (95% CI, 1.15–3.04; p for linear trend = 0.02) after adjusting for self-rated health status, physical activity and physical functioning. No significant associations between sRANKL or the ratio of OPG/sRANKL and hip fracture risk were observed. Conclusion Serum OPG levels were independently associated with a nearly twofold increased risk of hip fracture in postmenopausal women. PMID:23735608
Keyak, J H; Sigurdsson, S; Karlsdottir, G S; Oskarsdottir, D; Sigmarsdottir, A; Kornak, J; Harris, T B; Sigurdsson, G; Jonsson, B Y; Siggeirsdottir, K; Eiriksdottir, G; Gudnason, V; Lang, T F
2013-11-01
Proximal femoral (hip) strength computed by subject-specific CT scan-based finite element (FE) models has been explored as an improved measure for identifying subjects at risk of hip fracture. However, to our knowledge, no published study has reported the effect of loading condition on the association between incident hip fracture and hip strength. In the present study, we performed a nested age- and sex-matched case-control study in the Age Gene/Environment Susceptibility (AGES) Reykjavik cohort. Baseline (pre-fracture) quantitative CT (QCT) scans of 5500 older male and female subjects were obtained. During 4-7years follow-up, 51 men and 77 women sustained hip fractures. Ninety-seven men and 152 women were randomly selected as controls from a pool of age- and sex-matched subjects. From the QCT data, FE models employing nonlinear material properties computed FE-strength of the left hip of each subject in loading from a fall onto the posterolateral (FPL), posterior (FP) and lateral (FL) aspects of the greater trochanter (patent pending). For comparison, FE strength in stance loading (FStance) and total femur areal bone mineral density (aBMD) were also computed. For all loading conditions, the reductions in strength associated with fracture in men were more than twice those in women (p≤0.01). For fall loading specifically, posterolateral loading in men and posterior loading in women were most strongly associated with incident hip fracture. After adjusting for aBMD, the association between FP and fracture in women fell short of statistical significance (p=0.08), indicating that FE strength provides little advantage over aBMD for identifying female hip fracture subjects. However, in men, after controlling for aBMD, FPL was 424N (11%) less in subjects with fractures than in controls (p=0.003). Thus, in men, FE models of posterolateral loading include information about incident hip fracture beyond that in aBMD. © 2013.
Freedberg, D E; Haynes, K; Denburg, M R; Zemel, B S; Leonard, M B; Abrams, J A; Yang, Y-X
2015-10-01
Proton pump inhibitors (PPIs) are associated with risk for fracture in osteoporotic adults. In this population-based study, we found a significant association between PPIs and fracture in young adults, with evidence of a dose-response effect. Young adults who use PPIs should be cautioned regarding risk for fracture. Proton pump inhibitors (PPIs) are associated with fracture in adults with osteoporosis. Because PPI therapy may interfere with bone accrual and attainment of peak bone mineral density, we studied the association between use of PPIs and fracture in children and young adults. We conducted a population-based, case-control study nested within records from general medical practices from 1994 to 2013. Participants were 4-29 years old with ≥ 1 year of follow-up who lacked chronic conditions associated with use of long-term acid suppression. Cases of fracture were defined as the first incident fracture at any site. Using incidence density sampling, cases were matched with up to five controls by age, sex, medical practice, and start of follow-up. PPI exposure was defined as 180 or more cumulative doses of PPIs. Conditional logistic regression was used to estimate the odds ratio and confidence interval for use of PPIs and fracture. We identified 124,799 cases and 605,643 controls. The adjusted odds ratio for the risk of fracture associated with PPI exposure was 1.13 (95% CI 0.92 to 1.39) among children aged < 18 years old and 1.39 (95% CI 1.26 to 1.53) among young adults aged 18-29 years old. In young adults but not children, we observed a dose-response effect with increased total exposure to PPIs (p for trend <0.001). PPI use was associated with fracture in young adults, but overall evidence did not support a PPI-fracture relationship in children. Young adults who use PPIs should be cautioned regarding potentially increased risk for fracture, even if they lack traditional fracture risk factors.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-17
... Science Advisory Board can be found on the SAB Web site at http://www.epa.gov/sab . SUPPLEMENTARY...: (1) The SAB Environmental Engineering Committee Hydraulic Fracturing Research Plan Review; (2) the... regarding the planned research. The SAB Environmental Engineering Committee discussed its advice on April 7...
Hand grip strength and its correlation with vitamin D in Indian patients with hip fracture.
Dhanwal, Dinesh K; Dharmshaktu, Pramila; Gautam, V K; Gupta, N; Saxena, Alpana
2013-01-01
This case-control study was performed to evaluate 25-hydroxyvitamin D [25(OH)D] deficiency and its correlation with hand grip strength in 95 Indian hip fracture subjects and 95 controls. 25(OH)D deficiency was found in 88.4 % of hip fracture subjects that was significantly higher as compared to controls. Hand grip strength as measured by hand held dynamometer was significantly lower in patients, and there was a significant positive correlation between 25(OH)D and hand grip strength. The present study was conducted to assess correlation between 25(OH) D and hand grip strength in hip fracture subjects residing in North India. Ninety-five patients with hip fracture and similar number of controls were enrolled in the study. Fasting venous samples were analyzed for 25(OH)D, intact parathyroid hormone (PTH), alkaline phosphatase, calcium, and phosphate. Hand grip strength of study subjects was measured using Jamar dynamometer. Correlation between vitamin D levels and hand grip strength was analyzed in study population. The mean age of hip fracture subjects was 61.4 ± 12.6 years which was comparable in men and women. Out of 95 subjects, 57 were men and 38 were women. Mean 25(OH)D levels were significantly lower whereas intact PTH levels were significantly higher in patient group compared controls (10.29 ± 6.53 vs 13.6 ± 4.01 ng/ml; 62.6 ± 59.3 vs 37.7 ± 28.8 pg/ml, respectively). The number of subjects with 25(OH)D deficiency and secondary hyperparathyroidism was significantly higher in hip fracture group. The mean hand grip strength among hip fracture subjects was significantly lower compared to that of controls (16.57 ± 5.74 vs 26.74 ± 5.23 kg). There was a significant positive correlation between 25(OH)D and hand grip strength ( r = 0.482, p value <0.01) in hip fracture population. Majority of hip fracture patients in India have vitamin D deficiency, secondary hyperparathyroidism, and lower hand grip strength compared to controls. Further, there is significant positive correlation between 25(OH)D and hand grip strength.
Cheung, Wing-Hoi; Shen, Wan-Yiu; Dai, David Lok-Kwan; Lee, Kin Bong; Zhu, Tracy Y; Wong, Ronald Man-Yeung; Leung, Kwok-Sui
2018-02-28
To investigate the effectiveness and cost of an 18-month multi-disciplinary Comprehensive Fragility Fracture Management Program (CFFMP) for fragility hip fracture patients. Prospective cohort study. Elderly patients with hip fracture were recruited at their first postoperative follow-up in 2 district hospitals. The intervention group comprised patients from the hospital undergoing CFFMP, and the control group comprised patients from another hospital undergoing conventional care. CFFMP provided geri-orthopaedic co-management, physician consultations, group-exercise and vibration-therapy. Timed-up-and-go test (TUG), Elderly Mobility Scale (EMS), Berg Balance Scale (BBS) and fall risk screening (FS) were used to assess functional performance. Incidences of falls and secondary fractures, the cost of the programme and related healthcare resources were recorded. A total of 76 patients were included in the intervention group (mean age 77.9 years ((standard deviation; SD) 6.1) ) and 77 in the control group (79.9 (SD 7.2)), respectively. The re-fracture rate in the control group (10.39%) was significantly higher than in the intervention group (1.32%) (p = 0.034). The intervention group improved significantly in TUG, EMS and FS after a 1-year programme. The overall healthcare costs per patient in the intervention and control groups were US$22,450 and US$25,313, respectively. Multi-disciplinary CFFMP is effective, with reduced overall cost, reduced length of hospital stay and reduced secondary fracture rate. The rehabilitation community service favours rehabilitation and improved quality of life of hip fracture patients.
Sato, Yoshihiro; Kanoko, Tomohiro; Satoh, Kei; Iwamoto, Jun
A high incidence of fractures, particularly of the hip, represents an important problem in patients with Alzheimer disease (AD), who are prone to falls and have osteoporosis. We previously found that deficiency of 25-hydroxyvitamin D and compensatory hyperparathyroidism cause reduced bone mineral density in female patients with AD. We address the possibility that treatment with risedronate sodium and ergocalciferol plus calcium supplementation may reduce the incidence of nonvertebral fractures in elderly women with AD. A total of 500 elderly women with AD were randomly assigned to daily treatment with 2.5 mg of risedronate sodium or a placebo, combined with 1000 IU of ergocalciferol and 1200 mg of elementary calcium, and followed up for 18 months. At baseline, patients of both groups showed 25-hydroxyvitamin D deficiency with compensatory hyperparathyroidism. During the study period, bone mineral density in the risedronate group increased by 4.1% and decreased by 0.9% in the control group. Vertebral fractures occurred in 29 patients (24 hip fractures) in the control group and 8 patients (5 hip fractures) in the risedronate group. The relative risk in the risedronate group compared with the control group was 0.28 (95% confidence interval, 0.13-0.59). Elderly patients with AD hypovitaminosis D are at increased risk for hip fracture. Treatment with risedronate and ergocalciferol may be safe and effective in reducing the risk of a fracture in elderly patients with AD.
Bhola, Nitin; Jadhav, Anendd; Borle, Rajiv; Khemka, Gaurav; Adwani, Nitin; Bhattad, Mayur
2014-03-01
Mandibular fractures are relatively less frequent in children when compared to adults. Pediatric patients present a unique challenge to maxillofacial surgeons in terms of their treatment planning and in their functional needs. We currently describe our experience with lateral compression open cap splint with circummandibular wiring as a treatment modality which involves fewer risks in treating pediatric symphysis/parasymphysis/body mandibular fractures. A retrospective analysis of pediatric patients with mandibular symphysis/parasymphysis/body fractures operated from January 2007 to January 2012 was performed. Clinical photographs and orthopantomogram assessment at the time of presentation, after treatment, and at 6 months postoperatively were evaluated. All the 10 patients were followed up until the period of 6 months, and none of them had any major complications. Postoperatively, there was satisfactory healing and union of fracture fragments in all the patients. Only one patient developed infection at submental region. The 6-month follow-up showed good occlusion, without interference in teeth eruption and no signs of temporomandibular joint problems. Lateral compression open cap splints for treatment of pediatric mandibular symphysis/parasymphysis/body fractures are reliable treatment modalities with regard to occlusion-guided fracture reduction.
Rate of displacement for Jakob Type 1 lateral condyle fractures treated with a cast.
Zale, C; Winthrop, Z A; Hennrikus, W
2018-04-01
The aim of this retrospective study is to report the rate of displacement of Jakob Type 1 lateral condyle fractures that were initially treated in a cast. We performed a retrospective review of all patients that were treated for a non-displaced (Jakob Type 1 < 2 mm) lateral condyle fracture of the humerus at our institution between 2002 and 2015. A total of 59 patients were initially treated with casting. Five fractures displaced and were converted to a closed pinning treatment plan with a conversion rate of 8.5%. There was a mean of 13.2 days (4 to 21) between treatment by initial casting and closed pinning. This study demonstrates an 8.5% displacement and conversion rate from cast treatment to closed pinning for initially non-displaced Jakob Type 1 lateral condyle fractures of the humerus. The internal oblique radiograph is most accurate to determine displacement. We recommend obtaining an internal oblique view at initial evaluation and at follow-up in the cast for lateral condyle fractures. To minimize movement at the fracture site, we recommend treating Jakob Type 1 lateral condyle fractures with a long arm cast with the elbow at 90° and the forearm in the supine position with a sling-loop design. IV - retrospective therapeutic study.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phillips, W.S.; Rutledge, J.T.; Gardner, T.L.
1996-11-01
Patterns of microearthquakes detected downhole defined fracture orientation and extent in the Austin chalk, Giddings field, TX and the 76 field, Clinton Co., KY. We collected over 480 and 770 microearthquakes during hydraulic stimulation at two sites in the Austin chalk, and over 3200 during primary production in Clinton Co. Data were of high enough quality that 20%, 31% and 53% of the events could be located, respectively. Reflected waves constrained microearthquakes to the stimulated depths at the base of the Austin chalk. In plan view, microearthquakes defined elongate fracture zones extending from the stimulation wells parallel to the regionalmore » fracture trend. However, widths of the stimulated zones differed by a factor of five between the two Austin chalk sites, indicating a large difference in the population of ancillary fractures. Post-stimulation production was much higher from the wider zone. At Clinton Co., microearthquakes defined low-angle, reverse-fault fracture zones above and below a producing zone. Associations with depleted production intervals indicated the mapped fractures had been previously drained. Drilling showed that the fractures currently contain brine. The seismic behavior was consistent with poroelastic models that predicted slight increases in compressive stress above and below the drained volume.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phillips, W.S.; Rutledge, J.T.; Fairbanks, T.D.
1996-12-31
Patterns of microearthquakes detected downhole defined fracture orientation and extent in the Austin chalk, Giddings field, TX and the 76 field, Clinton Co., KY. We collected over 480 and 770 microearthquakes during hydraulic stimulation at two sites in the Austin chalk, and over 3200 during primary production in Clinton Co. Data were of high enough quality that 20%, 31% and 53% of the events could be located, respectively. Reflected waves constrained microearthquakes to the stimulated depths at the base of the Austin chalk. In plan view, microearthquakes defined elongate fracture zones extending from the stimulation wells parallel to the regionalmore » fracture trend. However, widths of the stimulated zones differed by a factor of live between the two Austin chalk sites, indicating a large difference in the population of ancillary fractures. Post-stimulation production was much higher from the wider zone. At Clinton Co., microearthquakes defined low-angle, reverse-fault fracture zones above and below a producing zone. Associations with depleted production intervals indicated the mapped fractures had been previously drained. Drilling showed that the fractures currently contain brine. The seismic behavior was consistent with poroelastic models that predicted slight increases in compressive stress above and below the drained volume.« less
Delayed union and nonunions: epidemiology, clinical issues, and financial aspects.
Hak, David J; Fitzpatrick, Daniel; Bishop, Julius A; Marsh, J Lawrence; Tilp, Susanne; Schnettler, Reinhard; Simpson, Hamish; Alt, Volker
2014-06-01
Fracture healing is a critically important clinical event for fracture patients and for clinicians who take care of them. The clinical evaluation of fracture healing is based on both radiographic findings and clinical findings. Risk factors for delayed union and nonunion include patient dependent factors such as advanced age, medical comorbidities, smoking, non-steroidal anti-inflammatory use, various genetic disorders, metabolic disease and nutritional deficiency. Patient independent factors include fracture pattern, location, and displacement, severity of soft tissue injury, degree of bone loss, quality of surgical treatment and presence of infection. Established nonunions can be characterised in terms of biologic capacity, deformity, presence or absence of infection, and host status. Hypertrophic, oligotrophic and atrophic radiographic appearances allow the clinician to make inferences about the degree of fracture stability and the biologic viability of the fracture fragments while developing a treatment plan. Non-unions are difficult to treat and have a high financial impact. Indirect costs, such as productivity losses, are the key driver for the overall costs in fracture and non-union patients. Therefore, all strategies that help to reduce healing time with faster resumption of work and activities not only improve medical outcome for the patient, they also help reduce the financial burden in fracture and non-union patients. Copyright © 2014 Elsevier Ltd. All rights reserved.
Temporal distribution of alcohol related facial fractures.
Lee, Kai H; Qiu, Michael; Sun, Jiandong
2017-11-01
This study aimed to address 2 important aspects of temporal pattern in alcohol-related facial fractures: (1) comparison of temporal pattern of alcohol-related facial fracture (alcohol group) presentation with non-alcohol-related fracture (non-alcohol group) presentation; (2) temporal pattern of patient demographic characteristics, injury characteristics, and surgical management in the alcohol group presentation. This study retrospectively examined the Victorian admitted episodes data set (VAED) for the years 2010 to 2013. VAED is a standardized set of data collected during all hospital presentations in Victoria. The study found higher incidence of alcohol-related facial fracture presentations during weekends and during the summer and spring months compared with non-alcohol-related fractures (statistically significant). Alcohol-related facial fractures are more likely to involve male patients in the 20- to 29-year age group, occur as a result of interpersonal violence, and require shorter hospital stays during weekend admissions (statistically significant). No statistically significant relationship has been observed in seasonal variation across all variables. This study found distinct characteristics in temporal distribution of alcohol-related facial fractures. These characteristics are, in particular, significant in weekend trauma admissions. Such information is important in workforce planning, resource distribution, and implementation of injury prevention programs. Copyright © 2017 Elsevier Inc. All rights reserved.
Segmentation of radiographic images under topological constraints: application to the femur.
Gamage, Pavan; Xie, Sheng Quan; Delmas, Patrice; Xu, Wei Liang
2010-09-01
A framework for radiographic image segmentation under topological control based on two-dimensional (2D) image analysis was developed. The system is intended for use in common radiological tasks including fracture treatment analysis, osteoarthritis diagnostics and osteotomy management planning. The segmentation framework utilizes a generic three-dimensional (3D) model of the bone of interest to define the anatomical topology. Non-rigid registration is performed between the projected contours of the generic 3D model and extracted edges of the X-ray image to achieve the segmentation. For fractured bones, the segmentation requires an additional step where a region-based active contours curve evolution is performed with a level set Mumford-Shah method to obtain the fracture surface edge. The application of the segmentation framework to analysis of human femur radiographs was evaluated. The proposed system has two major innovations. First, definition of the topological constraints does not require a statistical learning process, so the method is generally applicable to a variety of bony anatomy segmentation problems. Second, the methodology is able to handle both intact and fractured bone segmentation. Testing on clinical X-ray images yielded an average root mean squared distance (between the automatically segmented femur contour and the manual segmented ground truth) of 1.10 mm with a standard deviation of 0.13 mm. The proposed point correspondence estimation algorithm was benchmarked against three state-of-the-art point matching algorithms, demonstrating successful non-rigid registration for the cases of interest. A topologically constrained automatic bone contour segmentation framework was developed and tested, providing robustness to noise, outliers, deformations and occlusions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moon, H.Y.; Advani, S.H.; Lee, T.S.
1992-11-01
Hydraulic fracturing plays a pivotal role in the enhancement of oil and gas production recovery from low permeability reservoirs. The process of hydraulic fracturing entails the generation of a fracture by pumping fluids blended with special chemicals and proppants into the payzone at high injection rates and pressures to extend and wedge fractures. The mathematical modeling of hydraulically induced fractures generally incorporates coupling between the formation elasticity, fracture fluid flow, and fracture mechanics equations governing the formation structural responses, fluid pressure profile, and fracture growth. Two allied unsymmetric elliptic fracture models are developed for fracture configuration evolutions in three-layered rockmore » formations. The first approach is based on a Lagrangian formulation incorporating pertinent energy components associated with the formation structural responses and fracture fluid flow. The second model is based on a generalized variational principle, introducing an energy rate related functional. These models initially simulate a penny-shaped fracture, which becomes elliptic if the crack tips encounters (upper and/or lower) barriers with differential reservoir properties (in situ stresses, 16 elastic moduli, and fracture toughness-contrasts and fluid leak-off characteristics). The energy rate component magnitudes are determined to interpret the governing hydraulic fracture mechanisms during fracture evolution. The variational principle is extended to study the phenomenon and consequences of fluid lag in fractures. Finally, parametric sensitivity and energy rate investigations to evaluate the roles of controllable hydraulic treatment variables and uncontrollable reservoir property characterization parameters are performed. The presented field applications demonstrate the overall capabilities of the developed models. These studies provide stimulation treatment guidelines for fracture configuration design, control, and optimization.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wendberg, B.
1961-01-01
A study was made of 51 adult patients with tibial fractures by external counting with scintillation detectors over the thighs, knees, and tibias during a 14-day period after intravenous injection of 25 to 50 mu c Sr/sup 85/. The pattern of activity curves recorded over the fractured leg compared to those recorded over the control leg varied significantly with the age of the fracture (2 days to 9 yr). Increased uptake of Sr/sup 85/ was observed in all cases. The activity ratio fracture/control tibia obtained 14 days after injection rose during the 1st months after fracture to reach a peakmore » value 6 to 8 months after fracture. The mean 14-day fracture/ control ratios obtained 5 to 10 months after fracture was 15.5 plus or minus 7.2; then it dropped. Even 6 to 9 yr after fracture the counting rate over the fracture was higher than that over the intact tibia. No differences in activity uptake were observed between normally healing fractures and fractures showing delayed or nonunion. Activity curves obtained over the thigh, knee, and tibia of the fractured and intact legs 1 to l4 days after injection of Sr/sup 85/ could be simulated on the basis of a 2-compartment model for the kinetics of Sr in the body. Based on this kinetic analysis the externally recorded Sr/sup 85/ activity values may be interpreted as follows: The activity ratios fractured/intact leg obtained during early intervals after injection are mainly related to differences in the size of the exchangeable mineral spaces under the detector. The 14-day activity ratio of 2 anatomically comparable locations may be used as a relative index of the difference in the accretion rate (rate of irreversible deposition of bone mineral) in these locations, but is somewhat lower than the absolute dfference in the accretion rate. The bone salt laid down in the fracture callus is derived from the body fluids. The accretion rate in the fracture region is increased within a week of the fracture. It rapidly increases during the first months after fracture to reach a peak value at 6 to 8 months after fracture. The accretion rate in the entire fractured leg is increased some months after fracture. The traumatic osteopenia is caused by increased resorption and not by decreased accretion. (H.H.D.)« less
NASA Astrophysics Data System (ADS)
Sun, Shuai; Hou, Guiting; Zheng, Chunfang
2017-11-01
Stress variation associated with folding is one of the controlling factors in the development of tectonic fractures, however, little attention has been paid to the influence of neutral surfaces during folding on fracture distribution in a fault-related fold. In this study, we take the Cretaceous Bashijiqike Formation in the Kuqa Depression as an example and analyze the distribution of tectonic fractures in fault-related folds by core observation and logging data analysis. Three fracture zones are identified in a fault-related fold: a tensile zone, a transition zone and a compressive zone, which may be constrained by two neutral surfaces of fold. Well correlation reveals that the tensile zone and the transition zone reach the maximum thickness at the fold hinge and get thinner in the fold limbs. A 2D viscoelastic stress field model of a fault-related fold was constructed to further investigate the mechanism of fracturing. Statistical and numerical analysis reveal that the tensile zone and the transition zone become thicker with decreasing interlimb angle. Stress variation associated with folding is the first level of control over the general pattern of fracture distribution while faulting is a secondary control over the development of local fractures in a fault-related fold.
Environmental controls on micro fracture processes in shelf ice
NASA Astrophysics Data System (ADS)
Sammonds, Peter
2013-04-01
The recent retreat and collapse of the ice shelves on the Antarctic Peninsula has been associated with regional atmospheric warming, oceanic warming, increased summer melt and shelf flexure. Although the cause of collapse is a matter of active discussion, the process is that of fracture of a creep-brittle material, close to its melting point. The environmental controls on how fracturing initiates, at a micro-scale, strongly determine the macroscopic disintegration of ice shelves. In particular the shelf temperature profile controls the plasticity of the ice shelf; the densification of shelf ice due to melting and re-freezing affects the crack tip stress intensity; the accretion of marine ice at the bottom of the shelf imposes a thermal/mechanical discontinuity; saline environments control crack tip stress corrosion; cyclic loading promotes sub-critical crack propagation. These strong environmental controls on shelf ice fracture means that assessing shelf stability is a non-deterministic problem. How these factors may be parameterized in ice shelf models, through the use of fracture mechanisms maps, is discussed. The findings are discussed in relation to the stability of Larsen C.
Fracture Strength of Fused Silica From Photonic Signatures Around Collision Sites
NASA Technical Reports Server (NTRS)
Yost, William T.; Cramer, K Elliott
2015-01-01
Impact sites in glass affect its fracture strength. An analytical model that predicts fracture strength from grey-field polariscope (GFP) readings (photoelastic retardations) has been developed and reported in the literature. The model is suggestive that stress fields, resulting from impact damage, destablizes sites within the glass, which lead to pathways that cause strength degradation. Using data collected from fused silica specimens fabricated from outer window panes that were designed for the space shuttle, the model was tested against four categories of inflicted damage. The damage sites were cored from the window carcasses, examined with the GFP and broken using the ASTM Standard C1499-09 to measure the fracture strength. A correlation is made between the fracture strength and the photoelastic retardation measured at the damage site in each specimen. A least-squares fit is calculated. The results are compared with the predictions from the model. A plausible single-sided NDE damage site inspection method (a version of which is planned for glass inspection in the Orion Project) that relates photoelastic retardation in glass components to its fracture strength is presented.
Fracture Reactivation in Chemically Reactive Rock Systems
NASA Astrophysics Data System (ADS)
Eichhubl, P.; Hooker, J. N.
2013-12-01
Reactivation of existing fractures is a fundamental process of brittle failure that controls the nucleation of earthquake ruptures, propagation and linkage of hydraulic fractures in oil and gas production, and the evolution of fault and fracture networks and thus of fluid and heat transport in the upper crust. At depths below 2-3 km, and frequently shallower, brittle processes of fracture growth, linkage, and reactivation compete with chemical processes of fracture sealing by mineral precipitation, with precipitation rates similar to fracture opening rates. We recently found rates of fracture opening in tectonically quiescent settings of 10-20 μm/m.y., rates similar to euhedral quartz precipitation under these conditions. The tendency of existing partially or completely cemented fractures to reactivate will vary depending on strain rate, mineral precipitation kinetics, strength contrast between host rock and fracture cement, stress conditions, degree of fracture infill, and fracture network geometry. Natural fractures in quartzite of the Cambrian Eriboll Formation, NW Scotland, exhibit a complex history of fracture formation and reactivation, with reactivation involving both repeated crack-seal opening-mode failure and shear failure of fractures that formed in opening mode. Fractures are partially to completely sealed with crack-seal or euhedral quartz cement or quartz cement fragmented by shear reactivation. Degree of cementation controls the tendency of fractures for later shear reactivation, to interact elastically with adjacent open fractures, and their intersection behavior. Using kinematic, dynamic, and diagenetic criteria, we determine the sequence of opening-mode fracture formation and later shear reactivation. We find that sheared fracture systems of similar orientation display spatially varying sense of slip We attribute these inconsistent directions of shear reactivation to 1) a heterogeneous stress field in this highly fractured rock unit and 2) variations in the degree of fracture cement infill in fractures of same orientation, allowing fractures to reactivate at times when adjacent, more cemented fractures remain dormant. The observed interaction of chemical and mechanical fracture growth and sealing processes in this chemically reactive and heavily deformed rock unit results in a complex fracture network geometry not generally observed in less chemically reactive, shallower crustal environments.
Ferriero, Giorgio; Brunetto, Alessandro; Sartorio, Francesco; Vercelli, Stefano
2004-12-01
This article reports a 1-yr prospective study related to a bedridden patient with rotator cuff tear arthropathy featuring severe erosion of the proximal part of the humerus. To prevent spontaneous humeral fracture, a comprehensive intervention was planned. This included drug therapy for osteoporosis and pain, nurse team training on patient handling techniques, and patient and caregiver education. After 1 yr, clinical and radiologic findings are stable.
2012-03-01
18 3.3.7 Fractography ... Fractography : The fracture surfaces of the fractured fatigue specimens will be examined optically and in the scanning electron microscope to measure the size...scanned and added to the report containing the results from these fatigue tests. 3.3.7 Fractography Once a specimen has been tested, and assuming
Bhandari, Mohit; Sprague, Sheila; Schemitsch, Emil H
2009-07-01
Hip fractures are a significant cause of morbidity and mortality worldwide and the burden of disability associated with hip fractures globally vindicate the need for high-quality research to advance the care of patients with hip fractures. Historically, large, multi-centre randomized controlled trials have been rare in the orthopaedic trauma literature. Similar to other medical specialties, orthopaedic research is currently undergoing a paradigm shift from single centre initiatives to larger collaborative groups. This is evident with the establishment of several collaborative groups in Canada, in the United States, and in Europe, which has proven that multi-centre trials can be extremely successful in orthopaedic trauma research.Despite ever increasing literature on the topic of his fractures, the optimal treatment of hip fractures remains unknown and controversial. To resolve this controversy large multi-national collaborative randomized controlled trials are required. In 2005, the International Hip Fracture Research Collaborative was officially established following funding from the Canadian Institute of Health Research International Opportunity Program with the mandate of resolving controversies in hip fracture management. This manuscript will describe the need, the information, the organization, and the accomplishments to date of the International Hip Fracture Research Collaborative.
Evolution of a fracture network in an elastic medium with internal fluid generation and expulsion
NASA Astrophysics Data System (ADS)
Kobchenko, Maya; Hafver, Andreas; Jettestuen, Espen; Renard, François; Galland, Olivier; Jamtveit, Bjørn; Meakin, Paul; Dysthe, Dag Kristian
2014-11-01
A simple and reproducible analog experiment was used to simulate fracture formation in a low-permeability elastic solid during internal fluid/gas production, with the objective of developing a better understanding of the mechanisms that control the dynamics of fracturing, fracture opening and closing, and fluid transport. In the experiment, nucleation, propagation, and coalescence of fractures within an elastic gelatin matrix, confined in a Hele-Shaw cell, occurred due to CO2 production via fermentation of sugar, and it was monitored by optical means. We first quantified how a fracture network develops, and then how intermittent fluid transport is controlled by the dynamics of opening and closing of fractures. The gas escape dynamics exhibited three characteristic behaviors: (1) Quasiperiodic release of gas with a characteristic frequency that depends on the gas production rate but not on the system size. (2) A 1 /f power spectrum for the fluctuations in the total open fracture area over an intermediate range of frequencies (f ), which we attribute to collective effects caused by interaction between fractures in the drainage network. (3) A 1 /f2 power spectrum was observed at high frequencies, which can be explained by the characteristic behavior of single fractures.
Shah, Sheerin; Uppal, Sanjeev K.; Mittal, Rajinder K.; Garg, Ramneesh; Saggar, Kavita; Dhawan, Rishi
2016-01-01
Introduction: Because of its functional and cosmetic importance, facial injuries, especially bony fractures are clinically very significant. Missed and maltreated fractures might result in malocclusion and disfigurement of the face, thus making accurate diagnosis of the fracture very essential. In earlier times, conventional radiography along with clinical examination played a major role in diagnosis of maxillofacial fractures. However, it was noted that the overlapping nature of bones and the inability to visualise soft tissue swelling and fracture displacement, especially in face, makes radiography less reliable and useful. Computed tomography (CT), also called as X-ray computed radiography, has helped in solving this problem. This clinical study is to compare three-dimensional (3D) CT reconstruction with conventional radiography in evaluating the maxillofacial fractures preoperatively and effecting the surgical management, accordingly. Materials and Methods: Fifty patients, with suspected maxillofacial fractures on clinical examination, were subjected to conventional radiography and CT face with 3D reconstruction. The number and site of fractures in zygoma, maxilla, mandible and nose, detected by both the methods, were enumerated and compared. The final bearing of these additional fractures, on the management protocol, was analysed. Results: CT proved superior to conventional radiography in diagnosing additional number of fractures in zygoma, maxilla, mandible (subcondylar) and nasal bone. Coronal and axial images were found to be significantly more diagnostic in fracture sites such as zygomaticomaxillary complex, orbital floor, arch, lateral maxillary wall and anterior maxillary wall. Conclusion: 3D images gave an inside out picture of the actual sites of fractures. It acted as mind's eye for pre-operative planning and intra-operative execution of surgery. Better surgical treatment could be given to 33% of the cases because of better diagnostic ability of CT. PMID:27833286
Shah, Sheerin; Uppal, Sanjeev K; Mittal, Rajinder K; Garg, Ramneesh; Saggar, Kavita; Dhawan, Rishi
2016-01-01
Because of its functional and cosmetic importance, facial injuries, especially bony fractures are clinically very significant. Missed and maltreated fractures might result in malocclusion and disfigurement of the face, thus making accurate diagnosis of the fracture very essential. In earlier times, conventional radiography along with clinical examination played a major role in diagnosis of maxillofacial fractures. However, it was noted that the overlapping nature of bones and the inability to visualise soft tissue swelling and fracture displacement, especially in face, makes radiography less reliable and useful. Computed tomography (CT), also called as X-ray computed radiography, has helped in solving this problem. This clinical study is to compare three-dimensional (3D) CT reconstruction with conventional radiography in evaluating the maxillofacial fractures preoperatively and effecting the surgical management, accordingly. Fifty patients, with suspected maxillofacial fractures on clinical examination, were subjected to conventional radiography and CT face with 3D reconstruction. The number and site of fractures in zygoma, maxilla, mandible and nose, detected by both the methods, were enumerated and compared. The final bearing of these additional fractures, on the management protocol, was analysed. CT proved superior to conventional radiography in diagnosing additional number of fractures in zygoma, maxilla, mandible (subcondylar) and nasal bone. Coronal and axial images were found to be significantly more diagnostic in fracture sites such as zygomaticomaxillary complex, orbital floor, arch, lateral maxillary wall and anterior maxillary wall. 3D images gave an inside out picture of the actual sites of fractures. It acted as mind's eye for pre-operative planning and intra-operative execution of surgery. Better surgical treatment could be given to 33% of the cases because of better diagnostic ability of CT.
Bonaccorsi, Gloria; Fila, Enrica; Messina, Carmelo; Maietti, Elisa; Ulivieri, Fabio Massimo; Caudarella, Renata; Greco, Pantaleo; Guglielmi, Giuseppe
2017-10-01
To evaluate (a) the performance in predicting the presence of bone fractures of trabecular bone score (TBS) and hip structural analysis (HSA) in type 2 diabetic postmenopausal women compared to a control group and (b) the fracture prediction ability of TBS versus Fracture Risk Calculator (FRAX ® ) as well as whether TBS can improve the fracture prediction ability of FRAX ® in diabetic women. Eighty diabetic postmenopausal women were matched with 88 controls without major diseases for age and body mass index. The individual 10-year fracture risk was assessed by FRAX ® tool for Europe-Italy; bone mineral density (BMD) at lumbar spine, femoral neck and total hip was evaluated through dual-energy X-ray absorptiometry; TBS measurements were taken using the same region of interest as the BMD measurements; HSA was performed at proximal femur with the HSA software. Regarding variables of interest, the only significant difference between diabetic and control groups was observed for the value of TBS (median value: 1.215; IQR 1.138-1.285 in controls vs. 1.173; IQR 1.082-1.217 in diabetic; p = 0.002). The prevalence of fractures in diabetic women was almost tripled than in controls (13.8 vs. 3.4 %; p = 0.02). The receiver operator characteristic curve analysis showed that TBS alone (AUC = 0.71) had no significantly lower discriminative power for fracture prediction in diabetic women than FRAX major adjusted for TBS (AUC = 0.74; p = 0.65). In diabetic postmenopausal women TBS is an excellent tool in identifying fragility fractures.
Dipyrone has no effects on bone healing of tibial fractures in rats
Gali, Julio Cesar; Sansanovicz, Dennis; Ventin, Fernando Carvalho; Paes, Rodrigo Henrique; Quevedo, Francisco Carlos; Caetano, Edie Benedito
2014-01-01
OBJECTIVE: To evaluate the effect of dipyrone on healing of tibial fractures in rats. METHODS: Fourty-two Wistar rats were used, with mean body weight of 280g. After being anesthetized, they were submitted to closed fracture of the tibia and fibula of the right posterior paw through manual force. The rats were randomly divided into three groups: the control group that received a daily intraperitoneal injection of saline solution; group D-40, that received saline injection containing 40mg/Kg dipyrone; and group D-80, that received saline injection containing 80mg/Kg dipyrone. After 28 days the rats were sacrificed and received a new label code that was known by only one researcher. The fractured limbs were then amputated and X-rayed. The tibias were disarticulated and subjected to mechanical, radiological and histological evaluation. For statistical analysis the Kruskal-Wallis test was used at a significance level of 5%. RESULTS: There wasn't any type of dipyrone effect on healing of rats tibial fractures in relation to the control group. CONCLUSION: Dipyrone may be used safely for pain control in the treatment of fractures, without any interference on bone healing. Level of Evidence II, Controlled Laboratory Study. PMID:25246852
Merle, B; Chapurlat, R; Vignot, E; Thomas, T; Haesebaert, J; Schott, A-M
2017-05-01
We conducted a multicenter, randomized controlled trial to evaluate the impact of a population-based patient-centered post-fracture care program with a dedicated case manager, PREVention of OSTeoporosis (PREVOST), on appropriate post-fracture osteoporosis management. We showed that, compared to usual care, BMD investigation post-fracture was significantly improved (+20%) by our intervention program. Our study aims to evaluate the impact of a population-based patient-centered post-fracture care program, PREVOST, on appropriate post-fracture care. Multicenter, randomized controlled trial enrolling 436 women aged 50 to 85 years and attending a French hospital, for a low-energy fracture of the wrist or humerus. Randomization was stratified by age, hospital department, and site of fracture. The intervention was performed by a trained case manager who interacted only with the patients, with repeated oral and written information about fragility fractures and osteoporosis management, and prompting them to visit their primary care physicians. Control group received usual care. The primary outcome was the initiation of an appropriate post-fracture care defined by Bone Mineral Density (BMD) and/or anti-osteoporotic treatment prescription at 6 months. At 6 months, 53% of women in intervention group initiated a post-fracture care versus 33% for usual care (adjOR 2.35, 95%CI [1.58-3.50], p < 0.001). Post-fracture care was more frequent after wrist than humerus fracture (adjOR 1.93, 95%CI [1.14-3.30], p = 0.015) and decreased with age (adjOR for 10 years increase 0.76, 95%CI [0.61-0.96], p = 0.02). The intervention resulted in BMD prescription in 50% of patients (adjOR 2.10, 95%CI [1.41-3.11], p < 0.001) and in BMD performance in 41% of patients (adjOR 2.12, 95%CI [1.40-3.20], p < 0.001) versus 33 and 25% for usual care, respectively. Having performed a BMD increased treatment prescription; however, only 46% of women with a low BMD requiring a treatment according to the French guidelines received a prescription. A patient-centered care program with a dedicated case manager can significantly improve post-fracture BMD investigation.
Effect of Control Mode and Test Rate on the Measured Fracture Toughness of Advanced Ceramics
NASA Technical Reports Server (NTRS)
Hausmann, Bronson D.; Salem, Jonathan A.
2018-01-01
The effects of control mode and test rate on the measured fracture toughness of ceramics were evaluated by using chevron-notched flexure specimens in accordance with ASTM C1421. The use of stroke control gave consistent results with about 2% (statistically insignificant) variation in measured fracture toughness for a very wide range of rates (0.005 to 0.5 mm/min). Use of strain or crack mouth opening displacement (CMOD) control gave approx. 5% (statistically significant) variation over a very wide range of rates (1 to 80 µm/m/s), with the measurements being a function of rate. However, the rate effect was eliminated by use of dry nitrogen, implying a stress corrosion effect rather than a stability effect. With the use of a nitrogen environment during strain controlled tests, fracture toughness values were within about 1% over a wide range of rates (1 to 80 micons/m/s). CMOD or strain control did allow stable crack extension well past maximum force, and thus is preferred for energy calculations. The effort is being used to confirm recommendations in ASTM Test Method C1421 on fracture toughness measurement.
Otete, Harmony; Deleuran, Thomas; Fleming, Kate M; Card, Tim; Aithal, Guru P; Jepsen, Peter; West, Joe
2018-04-17
Cirrhosis, the prevalence of which is increasing, is a risk factor for osteoporosis and fractures. However, little is known of the actual risk of hip fractures in patients with alcoholic cirrhosis. Using linked primary and secondary care data from the English and Danish nationwide registries, we quantified the hip fracture risk in two national cohorts of patients with alcoholic cirrhosis. We followed 3,706 English and 17,779 Danish patients with a diagnosis of alcoholic cirrhosis, and we identified matched controls from the general populations. We estimated hazard ratios (HR) of hip fracture for patients vs. controls, adjusted for age, sex and comorbidity. The five-year hip fracture risk was raised both in England (2.9% vs. 0.8% for controls) and Denmark (4.6% vs. 0.9% for controls). With confounder adjustment, patients with cirrhosis had fivefold (adjusted HR 5.5; 95% CI 4.3-6.9), and 8.5-fold (adjusted HR 8.5; 95% CI 7.8-9.3) increased rates of hip fracture, in England and Denmark, respectively. This association between alcoholic cirrhosis and risk of hip fracture showed significant interaction with age (p <0.001), being stronger in younger age groups (under 45 years, HR 17.9 and 16.6 for English and Danish patients, respectively) than in patients over 75 years (HR 2.1 and 2.9, respectively). In patients with alcoholic cirrhosis, 30-day mortality following a hip fracture was 11.1% in England and 10.0% in Denmark, giving age-adjusted post-fracture mortality rate ratios of 2.8(95% CI 1.9-3.9) and 2.0(95% CI 1.5-2.7), respectively. Patients with alcoholic cirrhosis have a markedly increased risk of hip fracture and post-hip fracture mortality compared with the general population. These findings support the need for more effort towards fracture prevention in this population, to benefit individuals and reduce the societal burden. Alcoholic cirrhosis creates a large public health burden and is a risk factor for bone fractures. Based on data from England and Denmark, we found that hip fractures occur more than five times more frequently in people with alcoholic cirrhosis than in people without the disease. Additionally, the aftermath of the hip fracture is severe, such that up to 11% of patients with alcoholic cirrhosis die within 30 days after their hip fracture. These results suggest that efforts directed towards fracture prevention in people with alcoholic cirrhosis could be beneficial. Copyright © 2018 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
Kandemir, Nurgun; Slattery, Meghan; Ackerman, Kathryn E; Tulsiani, Shreya; Bose, Amita; Singhal, Vibha; Baskaran, Charumathi; Ebrahimi, Seda; Goldstein, Mark; Eddy, Kamryn; Klibanski, Anne; Misra, Madhusmita
2018-04-05
We have reported low bone mineral density (BMD), impaired bone structure, and increased fracture risk in anorexia nervosa (AN) and normal-weight, oligo-amenorrheic athletes (OA). However, data directly comparing compartment-specific bone parameters in AN, OA and controls are lacking. 426 females 14-21.9 years old were included; 231 AN, 94 OA and 101 normal-weight eumenorrheic controls. Dual energy x-ray absorptiometry was used to assess areal BMD (aBMD) of the whole body less head (WBLH), spine, and hip. High resolution peripheral quantitative CT was used to assess volumetric BMD (vBMD), bone geometry and structure at the non-weight bearing distal radius and weight-bearing distal tibia. AN had lower WBLH and hip aBMD Z-scores than OA and controls (p<0.0001). AN and OA had lower spine aBMD Z-scores than controls (p<0.01). At the radius, total and cortical vBMD, percent cortical area and thickness were lower in AN and OA vs. controls (p≤0.04); trabecular vBMD was lower in AN than controls. At the tibia, AN had lower measures for most parameters vs. OA and controls (p<0.05); OA had lower cortical vBMD than controls (p=0.002). AN and OA had higher fracture rates vs. controls. Stress fracture prevalence was highest in OA (p<0.0001); non-stress fracture prevalence was highest in AN (p<0.05). AN is deleterious to bone at all sites and both bone compartments. A high stress fracture rate in OA, who have comparable WBLH and hip aBMD measures to controls, indicates that BMD in these women may need to be even higher to avoid fractures.
Butezloff, Mariana Maloste; Zamarioli, Ariane; Leoni, Graziela Bianchi; Sousa-Neto, Manoel Damião; Volpon, Jose Batista
2015-11-01
To investigate the effect of vibration therapy on the bone callus of fractured femurs and the bone quality of intact femurs in ovariectomized rats. Fifty-six rats aged seven weeks were divided into four groups: control with femoral fracture (CON, n=14), ovariectomized with femoral fracture (OVX, n=14), control with femoral fracture plus vibration therapy (CON+VT, n=14), and ovariectomized with femoral fracture plus vibration therapy (OVX+VT, n=14). Three months after ovariectomy or sham surgery, a complete fracture was produced at the femoral mid-diaphysis and stabilized with a 1-mm-diameter intramedullary Kirschner wire. X-rays confirmed the fracture alignment and fixation. Three days later, the VT groups underwent vibration therapy (1 mm, 60 Hz for 20 minutes, three times per week for 14 or 28 days). The bone and callus quality were assessed by densitometry, three-dimensional microstructure, and mechanical test. Ovariectomized rats exhibited a substantial loss of bone mass and severe impairment in bone microarchitecture, both in the non-fractured femur and the bone callus. Whole-body vibration therapy exerted an important role in ameliorating the bone and fracture callus parameters in the osteoporotic bone. Vibration therapy improved bone quality and the quality of the fracture bone callus in ovariectomized rats.
Femoral neck shaft angle in men with fragility fractures.
Tuck, S P; Rawlings, D J; Scane, A C; Pande, I; Summers, G D; Woolf, A D; Francis, R M
2011-01-01
Introduction. Femoral neck shaft angle (NSA) has been reported to be an independent predictor of hip fracture risk in men. We aimed to assess the role of NSA in UK men. Methods. The NSA was measured manually from the DXA scan printout in men with hip (62, 31 femoral neck and 31 trochanteric), symptomatic vertebral (91), and distal forearm (67) fractures and 389 age-matched control subjects. Age, height, weight, and BMD (g/cm(2): lumbar spine, femoral neck, and total femur) measurements were performed. Results. There was no significant difference in mean NSA between men with femoral neck and trochanteric hip fractures, so all further analyses of hip fractures utilised the combined data. There was no difference in NSA between those with hip fractures and those without (either using the combined data or analysing trochanteric and femoral neck shaft fractures separately), nor between fracture subjects as a whole and controls. Mean NSA was smaller in those with vertebral fractures (129.2° versus 131°: P = 0.001), but larger in those with distal forearm fractures (129.8° versus 128.5°: P = 0.01). Conclusions. The conflicting results suggest that femoral NSA is not an important determinant of hip fracture risk in UK men.
Hydro-fracture in the laboratory: matching diagnostic seismic signals to fracture networks
NASA Astrophysics Data System (ADS)
Gehne, S.; Benson, P. M.; Koor, N.; Dobson, K. J.; Enfield, M.; Barber, A.
2017-12-01
Hydraulic fracturing is a key process in both natural (e.g. dyke intrusion) and engineered environments (e.g. shale gas). To better understand this process, we present new data from simulated hydraulic fracturing in a controlled laboratory environment in order to track fracture nucleation (location) and propagation (velocity) in space and time to assess the fracture mechanics and developing fracture network. Fluid overpressure is used to generate a permeable network of micro tensile fractures in an anisotropic sandstone and a highly anisotropic shale. A newly developed technique, using a steel guide arrangement to direct pressurised fluid into a sealed section of an axially drilled conduit, allows the pore fluid to contact the rock directly and to initiate tensile fractures from a pre-defined zone inside the sample. Acoustic emission location is used to record and map the nucleation and development of the micro-fracture network. For both rock types, fractures progresses parallel to the bedding plane (short-transverse) if the bedding plane is aligned with the direction of σ1 requiring breakdown pressures of approximately 7 and 13MPa respectively at a confining pressure of 8MPa. The data also indicates a more ductile behaviour of the shale than expected. We use X-Ray Computed Tomography (CT) to evaluate the evolved fracture network in terms of fracture pattern and aperture. Hydraulic fracturing produces very planar fractures in the shale, with axial fractures over the entire length of the sample broadly following the bedding. In contrast, fractures in the sandstone are more diffuse, linking pore spaces as they propagate. However, secondary micro cracking, branching of the main fracture, are also observed. These new experiments suggest that fracture pattern, fracture propagation trajectories, and fracturing fluid pressures are predominantly controlled by the interaction between the anisotropic mechanical properties of the rock and the anisotropic stress environment.
Forefoot Adduction Is a Risk Factor for Jones Fracture.
Fleischer, Adam E; Stack, Rebecca; Klein, Erin E; Baker, Jeffrey R; Weil, Lowell; Weil, Lowell Scott
Jones fractures are among the most common fractures of the foot; however, much remains unknown about their etiology. The purpose of the present study was to further examine the risk factors of forefoot and hindfoot alignment on Jones fractures using an epidemiologic study design. We used a retrospective, matched, case-control study design. Cases consisted of patients with acute, isolated Jones fractures confirmed on plain film radiographs seen at our institute from January 2009 to December 2013. Patients presenting with pain unrelated to metatarsal fractures served as controls. Controls were matched to cases by age (±2 years), gender, and year of presentation. Weightbearing foot radiographs were assessed for 13 angular relationships by a single rater. Conditional multivariable logistic regression was used to identify important risk factors. Fifty patients with acute Jones fractures and 200 controls were included. The only significant variables in the final multivariable model were the metatarsus adductus angle (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.08 to 1.25) and fourth/fifth intermetatarsal angle (OR 0.69, 95% CI 0.57 to 0.83)-both measures of static forefoot adduction. The presence of metatarsus adductus (defined as >15°) on foot radiographs was associated with a 2.4 times greater risk of a Jones fracture (adjusted OR 2.4, 95% CI 1.2 to 4.8). We have concluded that the risk of Jones fracture increases with an adducted forefoot posture. In our population, which consisted primarily of patients presenting after a fall (10 of 50; 20%) or misstep/inversion injury (19 of 50; 38%), the hindfoot alignment appeared to be a less important factor. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.
Bipolar disorder and the risk of fracture: A nationwide population-based cohort study.
Su, Jian-An; Cheng, Bi-Hua; Huang, Yin-Cheng; Lee, Chuan-Pin; Yang, Yao-Hsu; Lu, Mong-Liang; Hsu, Chung-Yao; Lee, Yena; McIntyre, Roger S; Chin Lin, Tzu; Chin-Hung Chen, Vincent
2017-08-15
The co-primary aims are: 1) to compare the risk of fracture between adults with bipolar disorder and those without bipolar disorder; and 2) to assess whether lithium, anticonvulsants and antipsychotics reduce risk of fracture among individuals with bipolar disorder. The analysis herein is a population-based retrospective cohort study, utilizing the National Health Insurance (NHI) medical claims data collected between 1997 and 2013 in Taiwan. We identified 3705 cases with incident diagnoses of bipolar disorder during study period and 37,050 matched controls without bipolar diagnoses. Incident diagnosis of fracture was operationalized as any bone fracture after the diagnosis of bipolar disorder or after the matched index date for controls. Bipolar patients had significantly higher risk of facture when compared to matched controls (17.6% versus 11.7%, respectively p<0.001). The hazard ratio (HR) was 1.33 (95% confidence interval [CI]=1.23-1.48, p<0.001) after adjusting for covariates. Persons with bipolar disorder and a prior history of psychiatric hospitalization were had higher risk for bone fracture than those without prior history of psychiatric hospitalization when compared to match controls. Higher cumulative dose of antipsychotics or mood stabilizers did not increase the risk of fracture. The diagnoses of bipolar disorder were not confirmed with structured clinical interview. Drug adherence, exact exposure dosage, smoking, lifestyle, nutrition and exercise habits were unable to be assessed in our dataset. Bipolar disorder is associated with increased risk of fracture, and higher cumulative dose of mood stabilizers and antipsychotics did not further increase the risk of fracture. Copyright © 2017 Elsevier B.V. All rights reserved.
The evolution of fracture surface roughness and its dependence on slip
NASA Astrophysics Data System (ADS)
Wells, Olivia L.
Under effective compression, impingement of opposing rough surfaces of a fracture can force the walls of the fracture apart during slip. Therefore, a fracture's surface roughness exerts a primary control on the amount of dilation that can be sustained on a fracture since the opposing surfaces need to remain in contact. Previous work has attempted to characterize fracture surface roughness through topographic profiles and power spectral density analysis, but these metrics describing the geometry of a fracture's surface are often non-unique when used independently. However, when combined these metrics are affective at characterizing fracture surface roughness, as well as the mechanisms affecting changes in roughness with increasing slip, and therefore changes in dilation. These mechanisms include the influence of primary grains and pores on initial fracture roughness, the effect of linkage on locally increasing roughness, and asperity destruction that limits the heights of asperities and forms gouge. This analysis reveals four essential stages of dilation during the lifecycle of a natural fracture, whereas previous slip-dilation models do not adequately address the evolution of fracture surface roughness: (1) initial slip companied by small dilation is mediated by roughness controlled by the primary grain and pore dimensions; (2) rapid dilation during and immediately following fracture growth by linkage of formerly isolated fractures; (3) wear of the fracture surface and gouge formation that minimizes dilation; and (4) between slip events cementation that modifies the mineral constituents in the fracture. By identifying these fundamental mechanisms that influence fracture surface roughness, this new conceptual model relating dilation to slip has specific applications to Enhanced Geothermal Systems (EGS), which attempt to produce long-lived dilation in natural fractures by inducing slip.
NASA Astrophysics Data System (ADS)
Xie, Fei; Wang, Dan; Wu, Ming; Yu, Chengxiang; Sun, Dongxu; Yang, Xu; Xu, Changhao
2018-04-01
The stress corrosion cracking (SCC) of X80 pipeline steel in simulated alkaline soil solution under different temperatures was investigated by slow-strain-rate testing, scanning electron microscopy and energy-dispersive spectroscopy. Results showed that the fracture was transgranular and brittle at 273 K to 278 K (0 °C to 5 °C), and the metal surface was dissolved by a large number of chloride ions. Furthermore, hydrogen embrittlement was caused by the hydrogen atom extended to the high-stress region. The fracture process was controlled by hydrogen-induced cracking, and SCC was highly sensitive at this stage. At 288 K to 298 K (15 °C to 25 °C), the fracture morphology was attributed to the mixed mode of ductile and brittle fractures, the fracture process was controlled by the mechanism of hydrogen-induced cracking and anodic dissolution, and the susceptibility to SCC decreased. When the temperature reached 308 K to 318 K (35 °C to 45 °C), the fracture was mainly intergranular and ductile, the fracture process was controlled by anodic dissolution, and SCC sensitivity was the smallest in this temperature range.
Hannemann, P F W; Mommers, E H H; Schots, J P M; Brink, P R G; Poeze, M
2014-08-01
The aim of this systematic review and meta-analysis was to evaluate the best currently available evidence from randomized controlled trials comparing pulsed electromagnetic fields (PEMF) or low-intensity pulsed ultrasound (LIPUS) bone growth stimulation with placebo for acute fractures. We performed a systematic literature search of the medical literature from 1980 to 2013 for randomized clinical trials concerning acute fractures in adults treated with PEMF or LIPUS. Two reviewers independently determined the strength of the included studies by assessing the risk of bias according to the criteria in the Cochrane Handbook for Systematic Reviews of Interventions. Seven hundred and thirty-seven patients from 13 trials were included. Pooled results from 13 trials reporting proportion of nonunion showed no significant difference between PEMF or LIPUS and control. With regard to time to radiological union, we found heterogeneous results that significantly favoured PEMF or LIPUS bone growth stimulation only in non-operatively treated fractures or fractures of the upper limb. Furthermore, we found significant results that suggest that the use of PEMF or LIPUS in acute diaphyseal fractures may accelerate the time to clinical union. Current evidence from randomized trials is insufficient to conclude a benefit of PEMF or LIPUS bone growth stimulation in reducing the incidence of nonunions when used for treatment in acute fractures. However, our systematic review and meta-analysis suggest that PEMF or LIPUS can be beneficial in the treatment of acute fractures regarding time to radiological and clinical union. PEMF and LIPUS significantly shorten time to radiological union for acute fractures undergoing non-operative treatment and acute fractures of the upper limb. Furthermore, PEMF or LIPUS bone growth stimulation accelerates the time to clinical union for acute diaphyseal fractures.
Use of Proton Pump inhibitors is Associated with Fractures in Young Adults: A Population-Based Study
Freedberg, Daniel E.; Haynes, Kevin; Denburg, Michelle R.; Zemel, Babette S.; Leonard, Mary B.; Abrams, Julian A.; Yang, Yu-Xiao
2015-01-01
Purpose Proton pump inhibitors (PPIs) are associated with fracture in adults with osteoporosis. Because PPI therapy may interfere with bone accrual and attainment of peak bone mineral density, we studied the association between use of PPIs and fracture in children and young adults. Methods We conducted a population-based, case-control study nested within records from general medical practices from 1994 to 2013. Participants were 4–29 years old with ≥1 year of follow-up who lacked chronic conditions associated with use of long-term acid suppression. Cases of fracture were defined as the first incident fracture at any site. Using incidence density sampling, cases were matched with up to 5 controls by age, sex, medical practice, and start of follow-up. PPI exposure was defined as 180 or more cumulative doses of PPIs. Conditional logistic regression was used to estimate the odds ratio and confidence interval for use of PPIs and fracture. Results We identified 124,799 cases and 605,643 controls. The adjusted odds ratio for the risk of fracture associated with PPI exposure was 1.13 (95% CI 0.92 to 1.39) among children aged < 18 years old and 1.39 (95% CI 1.26 to 1.53) among young adults aged 18–29 years old. In young adults but not children, we observed a dose-response effect with increased total exposure to PPIs (p for trend <.001). Conclusions PPI use was associated with fracture in young adults but overall evidence did not support a PPI-fracture relationship in children. Young adults who use PPIs should be cautioned regarding potentially increased risk for fracture, even if they lack traditional fracture risk factors. PMID:25986385
Gourion-Arsiquaud, Samuel; Lukashova, Lyudmilla; Power, Jon; Loveridge, Nigel; Reeve, Jonathan; Boskey, Adele L.
2012-01-01
After age 60 hip fracture risk strongly increases, but only a fifth of this increase is attributable to reduced mineral density (BMD, measured clinically). Changes in bone quality, specifically bone composition as measured by Fourier Transform Infrared spectroscopic imaging (FTIRI), also contribute to fracture risk. Here, FTIRI was applied to study the femoral neck and provide spatially derived information on its mineral and matrix properties in age-matched fractured and non-fractured bones. Whole femoral neck cross sections, divided into quadrants along the neck’s axis, from 10 women with hip fracture and 10 cadaveric controls were studied using FTIRI and micro-computed Tomography. Although 3-dimensional micro-CT bone mineral densities were similar, the mineral-to-matrix ratio was reduced in the cases of hip fracture, confirming previous reports. New findings were that the FTIRI microscopic variation (heterogeneity) of the mineral-to-matrix ratio was substantially reduced in the fracture group as was the heterogeneity of the carbonate-to-phosphate ratio. Conversely, the heterogeneity of crystallinity was increased. Increased variation of crystallinity was statistically associated with reduced variation of the carbonate-to-phosphate ratio. Anatomical variation in these properties between the different femoral neck quadrants was reduced in the fracture group compared to controls. While our treatment-naïve patients had reduced rather than increased bending resistance, these changes in heterogeneity associated with hip fracture are in another way comparable to the effects of experimental bisphosphonate therapy, which decreases heterogeneity and other indicators of bone’s toughness as a material. PMID:22865771
Formosa, Melissa M; Xuereb-Anastasi, Angela
2016-01-01
Osteoporosis and fractures are complex conditions influenced by an interplay of genetic and environmental factors. The aim of the study was to investigate three biochemical parameters including total serum calcium, total serum alkaline phosphatase (sALP) and albumin in relation to bone mineral density (BMD) at the lumbar spine and femoral neck (FN), and with all-type of low-trauma fractures in Maltese postmenopausal women. Levels were also correlated with age and physical activity. A case-control study of 1045 women was performed. Women who suffered a fracture were classified as cases whereas women without a fracture history were included as controls subdivided into normal, osteopenic, or osteoporotic according to their BMD measurements. Blood specimens were collected following good standard practice and testing was performed by spectrophotometry. Calcium and sALP levels were weakly correlated with FN BMD levels (calcium: r = -0.111, p = 0.002; sALP: r = 0.089, p = 0.013). Fracture cases had the lowest serum levels of calcium, sALP and albumin relative to all other control groups, which decreased with increasing age, possibly increasing fracture risk. Biochemical levels were lowest in women who sustained a hip fracture and more than one fracture. Biochemical parameters decreased with reduced physical activity; however, this was most evident for fracture cases. Reduced physical activity was associated with lower BMD levels at the hip, and to a lower extent at the spine. In conclusion, results suggest that levels of serum calcium and albumin could be indicative of fracture risk, whereas calcium levels and to lower extent sALP levels could be indicators of hip BMD.
Wu, Chi-Shin; Chang, Chia-Ming; Tsai, Yu-Ting; Huang, Ya-Wen; Tsai, Hui-Ju
2015-09-01
To investigate the association between antipsychotic treatment and risk of hip fracture in subjects with schizophrenia. Among patients with schizophrenia (ICD-9-CM code 295), 605 cases with hip fracture and 2,828 matched controls were identified from 2002 to 2011 using the National Health Insurance Research Database in Taiwan. The authors conducted a nested case-control study to investigate the association between antipsychotic treatment and risk of hip fracture in subjects with schizophrenia. The modifiable effects of age and gender were evaluated by stratified analysis. In addition, the effects of antipsychotic use, antipsychotic classes, and receptor-binding profiles of antipsychotics, individually, on hip fracture were estimated, and potential confounding factors were adjusted in subsequent analysis. Conditional logistic regressions were applied to determine the effect of antipsychotic treatment on hip fracture. Current antipsychotic use was associated with an increased risk for hip fracture (adjusted odds ratio [AOR] = 1.61; 95% CI, 1.24-2.10). Among current users, new users had a higher risk of hip fracture (AOR = 4.28; 95% CI, 1.76-10.36) than past users (AOR = 1.11; 95% CI, 0.79-1.56). In addition, a significant increased risk of hip fracture was noted in schizophrenia subjects with first-generation antipsychotic use (AOR = 1.59; 95%CI, 1.15-2.20) but not in those with second-generation antipsychotic use (AOR = 1.16; 95% CI, 0.91-1.48). These results extend previous findings and demonstrate an increased risk of hip fracture associated with antipsychotic use in schizophrenia subjects. Further investigation is needed to dissect the underlying mechanisms related to the effect of antipsychotic use on hip fracture in subjects at risk. © Copyright 2015 Physicians Postgraduate Press, Inc.
Fracture Strength of Endodontically Treated Teeth with Different Access Cavity Designs.
Plotino, Gianluca; Grande, Nicola Maria; Isufi, Almira; Ioppolo, Pietro; Pedullà, Eugenio; Bedini, Rossella; Gambarini, Gianluca; Testarelli, Luca
2017-06-01
The purpose of this study was to compare in vitro the fracture strength of root-filled and restored teeth with traditional endodontic cavity (TEC), conservative endodontic cavity (CEC), or ultraconservative "ninja" endodontic cavity (NEC) access. Extracted human intact maxillary and mandibular premolars and molars were selected and assigned to control (intact teeth), TEC, CEC, or NEC groups (n = 10/group/type). Teeth in the TEC group were prepared following the principles of traditional endodontic cavities. Minimal CECs and NECs were plotted on cone-beam computed tomographic images. Then, teeth were endodontically treated and restored. The 160 specimens were then loaded to fracture in a mechanical material testing machine (LR30 K; Lloyd Instruments Ltd, Fareham, UK). The maximum load at fracture and fracture pattern (restorable or unrestorable) were recorded. Fracture loads were compared statistically, and the data were examined with analysis of variance and the Student-Newman-Keuls test for multiple comparisons. The mean load at fracture for TEC was significantly lower than the one for the CEC, NEC, and control groups for all types of teeth (P < .05), whereas no difference was observed among CEC, NEC, and intact teeth (P > .05). Unrestorable fractures were significantly more frequent in the TEC, CEC, and NEC groups than in the control group in each tooth type (P < .05). Teeth with TEC access showed lower fracture strength than the ones prepared with CEC or NEC. Ultraconservative "ninja" endodontic cavity access did not increase the fracture strength of teeth compared with the ones prepared with CEC. Intact teeth showed more restorable fractures than all the prepared ones. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Peeters, N; Lemkens, P; Leach, R; Gemels B; Schepers, S; Lemmens, W
Facial trauma. Patients with facial trauma must be assessed in a systematic way so as to avoid missing any injury. Severe and disfiguring facial injuries can be distracting. However, clinicians must first focus on the basics of trauma care, following the Advanced Trauma Life Support (ATLS) system of care. Maxillofacial trauma occurs in a significant number of severely injured patients. Life- and sight-threatening injuries must be excluded during the primary and secondary surveys. Special attention must be paid to sight-threatening injuries in stabilized patients through early referral to an appropriate specialist or the early initiation of emergency care treatment. The gold standard for the radiographic evaluation of facial injuries is computed tomography (CT) imaging. Nasal fractures are the most frequent isolated facial fractures. Isolated nasal fractures are principally diagnosed through history and clinical examination. Closed reduction is the most frequently performed treatment for isolated nasal fractures, with a fractured nasal septum as a predictor of failure. Ear, nose and throat surgeons, maxillofacial surgeons and ophthalmologists must all develop an adequate treatment plan for patients with complex maxillofacial trauma.
2012-01-01
Calcaneal fractures are common injuries involving the hind foot and often a source of significant long-term morbidity. Treatment options have changed throughout the ages from periods of preferred nonoperative management to closed reduction with a mallet, and more recently, open reduction and anatomic internal fixation. The current treatment of choice; however, is often debated, as open management of these fractures carries many risks to include wound breakdown and infection. A less invasive form of surgical management through small incisions, while maintaining the ability to obtain joint congruency, anatomic alignment, and restore calcaneal height and width would be ideal. We propose a novel form of fracture reduction using an inflatable bone tamp and percutaneous fracture fixation. Preoperative planning and experienced fluoroscopy is crucial to successful management using this method. Although we achieved successful radiographic outcome in this case, long-term functional outcome of this technique are yet to be published. PMID:22420710
Intra-articular fractures of the distal tibia
Sitnik, Alexandre; Beletsky, Aleksander; Schelkun, Steven
2017-01-01
Results of the treatment of intra-articular fractures of the distal tibia have improved significantly during the last two decades. Recognition of the role of soft tissues has led to the development of a staged treatment strategy. At the first stage, joint-bridging external fixation and fibular fixation are performed. This leads to partial reduction of the distal tibial fracture and allows time for the healing of soft tissues and detailed surgical planning. Definitive open reduction and internal fixation of the tibial fracture is performed at a second stage, when the condition of the soft tissues is safe. The preferred surgical approach(es) is chosen based on the fracture morphology as determined from standard radiographic views and computed tomography. Meticulous atraumatic soft-tissue handling and the use of modern fixation techniques for the metaphyseal component such as minimally invasive plate osteosynthesis further facilitate healing. Cite this article: EFORT Open Rev 2017;2:352-361. DOI: 10.1302/2058-5241.2.150047 PMID:28932487
Potential of hydraulically induced fractures to communicate with existing wellbores
NASA Astrophysics Data System (ADS)
Montague, James A.; Pinder, George F.
2015-10-01
The probability that new hydraulically fractured wells drilled within the area of New York underlain by the Marcellus Shale will intersect an existing wellbore is calculated using a statistical model, which incorporates: the depth of a new fracturing well, the vertical growth of induced fractures, and the depths and locations of existing nearby wells. The model first calculates the probability of encountering an existing well in plan view and combines this with the probability of an existing well-being at sufficient depth to intersect the fractured region. Average probability estimates for the entire region of New York underlain by the Marcellus Shale range from 0.00% to 3.45% based upon the input parameters used. The largest contributing parameter on the probability value calculated is the nearby density of wells meaning that due diligence by oil and gas companies during construction in identifying all nearby wells will have the greatest effect in reducing the probability of interwellbore communication.
de Avila, Érica Dorigatti; de Molon, Rafael Scaf; Cardoso, Mauricio de Almeida; Capelozza Filho, Leopoldino; Campos Velo, Marilia Mattar de Amoêdo; Mollo, Francisco de Assis; Borelli Barros, Luiz Antonio
2014-01-01
The aim of this paper is to present a complex rehabilitation, of fractured tooth, with implants in anterior region considering the orthodontics extrusion to clinical success. At 7 years old, the patient fractured the maxillary left central incisor and the dentist did a crown with the fragment. Twenty years later, the patient was referred to a dental clinic for orthodontic treatment, with the chief complaint related to an accentuated deep bite, and a professional started an orthodontic treatment. After sixteen months of orthodontic treatment, tooth 21 fractured. The treatment plan included an orthodontic extrusion of tooth 21 and implant placement. This case has been followed up and the clinical and radiographic examinations show excellence esthetic results and satisfaction of patient. The forced extrusion can be a viable treatment option in the management of crown root fracture of an anterior tooth to gain bone in a vertical direction. This case emphasizes that to achieve the esthetic result a multidisciplinary approach is necessary. PMID:24872900
2013-01-22
This image from NASA 2001 Mars Odyssey spacecraft of the Claritas Fossae region illustrates how fractures affect other features. In this instance, the fractures control the path of several channels from upper right towards lower left.
Geissler, Joseph R.; Bajaj, Devendra; Fritton, J. Christopher
2015-01-01
The biomechanics literature contains many well-understood mechanisms behind typical fracture types that have important roles in treatment planning. The recent association of “atypical” fractures with long-term use of drugs designed to prevent osteoporosis has renewed interest in the effects of agents on bone tissue-level quality. While this class of fracture was recognized prior to the introduction of the anti-resorptive bisphosphonate drugs and recently likened to stress fractures, the mechanism(s) that lead to atypical fractures have not been definitively identified. Thus, a causal relationship between these drugs and atypical fracture has not been established. Physicians, bioengineers and others interested in the biomechanics of bone are working to improve fracture-prevention diagnostics, and the design of treatments to avoid this serious side-effect in the future. This review examines the mechanisms behind the bone tissue damage that may produce the atypical fracture pattern observed increasingly with long-term bisphosphonate use. Our recent findings and those of others reviewed support that the mechanisms behind normal, healthy excavation and tunnel filling by bone remodeling units within cortical tissue strengthen mechanical integrity. The ability of cortical bone to resist the damage induced during cyclic loading may be altered by the reduced remodeling and increased tissue age resulting from long-term bisphosphonate treatment. Development of assessments for such potential fractures would restore confidence in pharmaceutical treatments that have the potential to spare millions in our aging population from the morbidity and death that often follow bone fracture. PMID:25683519
Hip fracture in hospitalized medical patients.
Zapatero, Antonio; Barba, Raquel; Canora, Jesús; Losa, Juan E; Plaza, Susana; San Roman, Jesús; Marco, Javier
2013-01-08
The aim of the present study is to analyze the incidence of hip fracture as a complication of admissions to internal medicine units in Spain. We analyzed the clinical data of 2,134,363 adults who had been admitted to internal medicine wards. The main outcome was a diagnosis of hip fracture during hospitalization.Outcome measures included rates of in-hospital fractures, length of stay and cost. A total of 1127 (0.057%) admittances were coded with an in-hospital hip fracture. In hospital mortality rate was 27.9% vs 9.4%; p < 0.001, and the mean length of stay was significantly longer for patients with a hip fracture (20.7 days vs 9.8 days; p < 0.001). Cost were higher in hip-fracture patients (6927€ per hospitalization vs 3730€ in non fracture patients). Risk factors related to fracture were: increasing age by 10 years increments (OR 2.32 95% CI 2.11-2.56), female gender (OR 1.22 95% CI 1.08-1.37), admission from nursing home (OR 1.65 95% CI 1.27-2.12), dementia (1.55 OR 95% CI1.30-1.84), malnutrition (OR 2.50 95% CI 1.88-3.32), delirium (OR 1.57 95% CI 1.16-2.14), and anemia (OR 1.30 95%CI 1.12-1.49). In-hospital hip fracture notably increased mortality during hospitalization, doubling the mean length of stay and mean cost of admission. These are reasons enough to stress the importance of designing and applying multidisciplinary plans focused on reducing the incidence of hip fractures in hospitalized patients.
Iolascon, Giovanni; Moretti, Antimo; Giamattei, Maria Teresa; Migliaccio, Silvia; Gimigliano, Francesca
2015-10-01
Fragility fractures are a major burden for health and social care in elderly people. In order to identify earlier the "frail elders", new concepts of "dysmobility syndrome" and skeletal muscle function deficit (SMFD), including sarcopenia, osteoporosis, obesity, and mobility limitation, leading to a higher risk of fractures, have been recently introduced. There are very few studies investigating the association between fragility fractures and both the dysmobility syndrome and the SMFD. The objective of our study is to investigate the role of previous fragility fractures as a risk factor in determining the dysmobility syndrome and/or the SMFD in post-menopausal women. In this case-control study, we retrospectively examined data from the medical records of post-menopausal women aged 50 or older. We divided the study population in two groups. The first group includes women with a previous fragility fracture (cases) and the other group includes women without any previous osteoporotic fracture (controls). We identified the subjects with "dysmobility syndrome", "dynapenic SMFD", "sarcopenic SMFD", and "mixed SMFD" in both groups. Data collected refer to a 6-month period. We retrieved data of 121 post-menopausal women, 77 (63.64%) had already sustained a fragility fracture at any site (cases). The risk for dysmobility syndrome was significantly higher (adjusted OR for age and serum 25-OH vitamin D3 of 2.46) in the cases compared with the controls. An early diagnosis of conditions limiting mobility, including dysmobility syndrome, might be useful to identify, among patients with osteoporotic fractures, those who might have a higher risk of a new fragility fracture.
Celiac disease is not increased in women with hip fractures and low vitamin D levels.
Leboff, M S; Cobb, H; Gao, L Y; Hawkes, W; Yu-Yahiro, J; Kolatkar, N S; Magaziner, J
2013-01-01
Celiac disease is associated with decreased bone density; however, the risk of fractures in celiac disease patients is unclear. We compared the prevalence of celiac disease between a group of women with hip fractures and a group of women undergoing elective joint replacement surgery and the association between celiac disease and vitamin D levels. Two hundred eight community dwelling and postmenopausal women were recruited from Boston, MA (n=81) and Baltimore, MD (n=127). We measured tissue transglutaminase IgA by ELISA to diagnose celiac disease and 25-hydroxyvitamin D (25(OH)D) levels by radioimmunoassay in both women with hip fractures (n=157) and a control group (n=51) of total hip replacement subjects from Boston. Subjects were excluded if they took any medications or had medical conditions that might affect bone. Median serum 25(OH)D levels were significantly lower (p< 0.0001) in the hip fracture cohorts compared to the elective joint replacement cohort (14.1 ng/ml vs. 21.3 ng/ml, respectively). There were no differences in the percentage of subjects with a positive tissue transglutaminase in the women with hip fractures versus the control group (1.91% vs. 1.96%, respectively). Vitamin D levels are markedly reduced in women with hip fractures, however hip fracture patients did not show a higher percentage of positive tissue transglutaminase levels compared with controls. These data suggest that routine testing for celiac disease among hip fracture patients may not be necessary in the absence of clinical signs and symptoms, although data from larger studies among hip fracture subjects are needed.
Fleming, Brandon J.; Hammond, Patrick A.; Stranko, Scott A.; Duigon, Mark T.; Kasraei, Saeid
2012-01-01
The fractured rock region of Maryland, which includes land areas north and west of the Interstate 95 corridor, is the source of water supply for approximately 4.4 million Marylanders, or approximately 76 percent of the State's population. Whereas hundreds of thousands of residents rely on wells (both domestic and community), millions rely on surface-water sources. In this region, land use, geology, topography, water withdrawals, impoundments, and other factors affect water-flow characteristics. The unconfined groundwater systems are closely interconnected with rivers and streams, and are affected by seasonal and climatic variations. During droughts, groundwater levels drop, thereby decreasing well yields, and in some cases, wells have gone dry. Low ground-water levels contribute to reduced streamflows, which in turn, can lead to reduced habitat for aquatic life. Increased demand, over-allocation, population growth, and climate change can affect the future sustainability of water supplies in the region of Maryland underlain by fractured rock. In response to recommendations of the 2008 Advisory Committee on the Management and Protection of the State's Water Resources report, the Maryland Department of the Environment's Water Supply Program, the Maryland Geological Survey, the Maryland Department of Natural Resources, Monitoring and Non-Tidal Assessment (MANTA) Division, and the U.S. Geological Survey have developed a science plan for a comprehensive assessment that will provide new scientific information, new data analysis, and new tools for the State to better manage water resources in the fractured rock region of Maryland. The science plan lays out five goals for the comprehensive assessment: (1) develop tools for the improved management and investigation of groundwater and surface-water resources; (2) characterize factors affecting reliable yields of individual groundwater and surface-water supplies; (3) investigate impacts on nearby water withdrawal users caused by groundwater and surface-water withdrawals; (4) assess the role of streamflow and water withdrawals on the ecological integrity of streams; and (5) improve understanding of the distribution of water-quality conditions in fractured rock aquifers. To accomplish these goals, accurate data collection, review, and analysis are needed, including the study of "Research Watersheds" that can provide detailed information about the potential effects that climate change and water withdrawals may have on groundwater, streamflow, and aquatic life. The assessment planning started in 2009 and is being conducted with close interagency coordination. A Fractured Rock Aquifer Information System is currently (2012) undergoing initial development. Other major tasks that will be performed include the development of work plans for each science goal, the estimation of daily streamflow at ungaged streams, and the design and implementation of Research Watersheds. Finally, scenarios will be modeled to evaluate current water allocation permitting methodologies, investigate effects on nearby water withdrawal users caused by groundwater and surface-water withdrawals, and assess the potential impacts of climate change on water resources. Desktop and Web-based tools will be developed in order to meet the diverse research needs of the assessment. These tools, including the Fractured Rock Aquifer Information System will be continuously improved during the assessment to store relevant groundwater and surface-water data in spatially referenced databases, estimate streamflows, locate higher-yielding wells, estimate the impacts of withdrawals on nearby users, and assess the cumulative impacts of withdrawals on the aquatic resource. Tools will be developed to serve the needs of many audiences, including water resource managers, water suppliers, planners, policymakers, and other scientific investigators.
The effect of long-term bisphosphonate therapy on trabecular bone strength and microcrack density
Jin, A.; Cobb, J.; Hansen, U.; Bhattacharya, R.; Reinhard, C.; Vo, N.; Atwood, R.; Li, J.; Karunaratne, A.; Wiles, C.
2017-01-01
Objectives Bisphosphonates (BP) are the first-line treatment for preventing fragility fractures. However, concern regarding their efficacy is growing because bisphosphonate is associated with over-suppression of remodelling and accumulation of microcracks. While dual-energy X-ray absorptiometry (DXA) scanning may show a gain in bone density, the impact of this class of drug on mechanical properties remains unclear. We therefore sought to quantify the mechanical strength of bone treated with BP (oral alendronate), and correlate data with the microarchitecture and density of microcracks in comparison with untreated controls. Methods Trabecular bone from hip fracture patients treated with BP (n = 10) was compared with naïve fractured (n = 14) and non-fractured controls (n = 6). Trabecular cores were synchrotron scanned and micro-CT scanned for microstructural analysis, including quantification of bone volume fraction, microarchitecture and microcracks. The specimens were then mechanically tested in compression. Results BP bone was 28% lower in strength than untreated hip fracture bone, and 48% lower in strength than non-fractured control bone (4.6 MPa vs 6.4 MPa vs 8.9 MPa). BP-treated bone had 24% more microcracks than naïve fractured bone and 51% more than non-fractured control (8.12/cm2 vs 6.55/cm2 vs 5.25/cm2). BP and naïve fracture bone exhibited similar trabecular microarchitecture, with significantly lower bone volume fraction and connectivity than non-fractured controls. Conclusion BP therapy had no detectable mechanical benefit in the specimens examined. Instead, its use was associated with substantially reduced bone strength. This low strength may be due to the greater accumulation of microcracks and a lack of any discernible improvement in bone volume or microarchitecture. This preliminary study suggests that the clinical impact of BP-induced microcrack accumulation may be significant. Cite this article: A. Jin, J. Cobb, U. Hansen, R. Bhattacharya, C. Reinhard, N. Vo, R. Atwood, J. Li, A. Karunaratne, C. Wiles, R. Abel. The effect of long-term bisphosphonate therapy on trabecular bone strength and microcrack density. Bone Joint Res 2017;6:602–609. DOI: 10.1302/2046-3758.610.BJR-2016-0321.R1. PMID:29066534
Fracture Fluid Additive and Formation Degradations
This presentation is on reactions that describe the degradation of fracturing fluids & formations during the hydraulic fracturing process & the clean‐up period. It contains a description of primary chemical reaction controls, & common degradation reactions
Shepstone, Lee; Lenaghan, Elizabeth; Cooper, Cyrus; Clarke, Shane; Fong-Soe-Khioe, Rebekah; Fordham, Richard; Gittoes, Neil; Harvey, Ian; Harvey, Nick; Heawood, Alison; Holland, Richard; Howe, Amanda; Kanis, John; Marshall, Tarnya; O'Neill, Terence; Peters, Tim; Redmond, Niamh; Torgerson, David; Turner, David; McCloskey, Eugene
2018-02-24
Despite effective assessment methods and medications targeting osteoporosis and related fractures, screening for fracture risk is not currently advocated in the UK. We tested whether a community-based screening intervention could reduce fractures in older women. We did a two-arm randomised controlled trial in women aged 70-85 years to compare a screening programme using the Fracture Risk Assessment Tool (FRAX) with usual management. Women were recruited from 100 general practitioner (GP) practices in seven regions of the UK: Birmingham, Bristol, Manchester, Norwich, Sheffield, Southampton, and York. We excluded women who were currently on prescription anti-osteoporotic drugs and any individuals deemed to be unsuitable to enter a research study (eg, known dementia, terminally ill, or recently bereaved). The primary outcome was the proportion of individuals who had one or more osteoporosis-related fractures over a 5-year period. In the screening group, treatment was recommended in women identified to be at high risk of hip fracture, according to the FRAX 10-year hip fracture probability. Prespecified secondary outcomes were the proportions of participants who had at least one hip fracture, any clinical fracture, or mortality; and the effect of screening on anxiety and health-related quality of life. This trial is registered with the International Standard Randomised Controlled Trial registry, number ISRCTN 55814835. 12 483 eligible women were identified and participated in the trial, and 6233 women randomly assigned to the screening group between April 15, 2008, and July 2, 2009. Treatment was recommended in 898 (14%) of 6233 women. Use of osteoporosis medication was higher at the end of year 1 in the screening group compared with controls (15% vs 4%), with uptake particularly high (78% at 6 months) in the screening high-risk subgroup. Screening did not reduce the primary outcome of incidence of all osteoporosis-related fractures (hazard ratio [HR] 0·94, 95% CI 0·85-1·03, p=0·178), nor the overall incidence of all clinical fractures (0·94, 0·86-1·03, p=0·183), but screening reduced the incidence of hip fractures (0·72, 0·59-0·89, p=0·002). There was no evidence of differences in mortality, anxiety levels, or quality of life. Systematic, community-based screening programme of fracture risk in older women in the UK is feasible, and could be effective in reducing hip fractures. Arthritis Research UK and Medical Research Council. Copyright © 2018 Elsevier Ltd. All rights reserved.
Sosa, Daysi Duarte; Eriksen, Erik Fink
2017-07-01
The aim of the study was to test, whether bone material strength differs between different subtypes of osteoporotic fracture and assess whether it relates to vertebral fracture severity. Cortical bone material strength index (BMSi) was measured by impact microindentation in 66 women with osteoporotic fracture and 66 age- and sex-matched controls without fracture. Bone mineral density (BMD) and bone turnover markers were also assessed. Vertebral fracture severity was graded by semiquantitative (SQ) grading. Receiver operator characteristic (ROC) curves were used to examine the ability of BMSi to discriminate fractures. Subjects with osteoporotic fractures exhibited lower BMSi than controls (71.5 ± 7.3 vs. 76.4 ± 6.2, p < 0.001). After adjusting for age and hip BMD, a significant negative correlation was seen between BMSi and vertebral fracture severity (r 2 = 0.19, p = 0.007). A decrease of one standard deviation (SD) in BMSi was associated with increased risk of fracture (OR 2.62; 95% CI 1.35, 5.10, p = 0.004). ROC curve areas under the curve (AUC) for BMSi in subjects with vertebral fracture (VF), hip fracture (HF), and non-vertebral non-hip fracture (NVNHFx), (mean; 95% CI) were 0.711 (0.608; 0.813), 0.712 (0.576; 0.843), 0.689 (0.576; 0.775), respectively. Combining BMSi and BMD provided further improvement in the discrimination of fractures with AUC values of 0.777 (0.695; 0.858), 0.789 (0.697; 0.882), and 0.821 (0.727; 0.914) for VFx, HFx, and NVNHFx, respectively. Low BMSi of the tibial cortex is associated with increased risk of all osteoporotic fractures and severity of vertebral fractures.
Sato, Yoshihiro; Honda, Yoshiaki; Umeno, Kazuo; Hayashida, Norimasa; Iwamoto, Jun; Takeda, Tsuyoshi; Matsumoto, Hideo
2011-01-01
A high incidence of fractures, particularly of the hip, represents an important problem in patients with Alzheimer disease (AD), who are prone to falls and have osteoporosis. We previously found that vitamin K deficiency and low 25-hydroxyvitamin D (25-OHD) with compensatory hyperparathyroidism cause reduced bone mineral density (BMD) in female patients with AD. This may modifiable by intervention with menatetrenone (vitamin K2) and risedronate sodium; we address the possibility that treatment with menatetrenone, risedronate and calcium may reduce the incidence of nonvertebral fractures in elderly patients with AD. A total of 231 elderly patients with AD were randomly assigned to daily treatment with 45 mg of menatetrenone or a placebo combined with once weekly risedronate sodium, and followed up for 12 months. At baseline, patients of both groups showed high undercarboxylated osteocalcin (ucOC) and low 25-OHD insufficiency with compensatory hyperparathyroidism. During the study period, BMD in the treatment group increased by 5.7% and increased by 2.1% in the control group. Nonvertebral fractures occurred in 15 patients (10 hip fractures) in the control group and 5 patients (2 hip fractures) in the treatment group. The relative risk in the treatment group compared with the control group was 0.31 (95% confidence interval, 0.12-0.81). Elderly AD patients with hypovitaminosis K and D are at increased risk for hip fracture. The study medications were well tolerated with relatively few adverse events and effective in reducing the risk of a fracture in elderly patients with AD.
Imaging in traumatic mandibular fractures
Gemal, Hugo; Reed, Duncan
2017-01-01
A fracture of the mandible is a common trauma presentation amongst young males and represents one of the most frequently encountered fractured bones within the viscerocranium. Historically, assault was the dominant contributing factor but now due to the increased number of vehicles used per capita, motor vehicle accidents are the primary cause. Mandibular fractures can be classified anatomically, by dentition, by muscle group and by severity. The fracture may also be closed, open, comminuted, displaced or pathological. It is important that the imaging modality used identifies the classification as this will decide definitive treatment. X-ray projections have typically been used to detect a mandibular fracture, but are limited to an anteroposterior (AP), lateral and oblique view in an unstable trauma patient. These views are inadequate to detail the level of fracture displacement and show poor detail of the condylar region. Computer tomography (CT) is the imaging modality of choice when assessing a traumatic mandibular injury and can demonstrate a 100% sensitivity in detecting a fracture. This is through use of a multidetector-row CT, which reduces motion blur and therefore produces accurate coronal and sagittal reconstructions. Furthermore, reconstructive three-dimensional CT images gained from planar views, allows a better understanding of the spatial relationship of the fracture with other anatomical landmarks. This ensures a better appreciation of the severity and classification of a mandibular fracture, which therefore influences operative planning. Ultrasound is another useful modality in detecting a mandibular fracture when the patient is too unstable to be transferred to a CT scanner. The sensitivity however is less in comparison to a CT series of images and provides limited detail on the fracture pattern. Magnetic resonance imaging demonstrates use in assessing soft tissue injury of the temporomandibular joint but this is unlikely to be of priority when initially assessing a trauma patient. PMID:28932703
Callus features of regenerate fracture cases in femoral lengthening in achondroplasia.
Devmurari, Kamlesh N; Song, Hae Ryong; Modi, Hitesh N; Venkatesh, K P; Ju, Kim Seung; Song, Sang Heon
2010-09-01
We studied the callus features seen in cases of regenerate fracture in femoral lengthening using a monolateral fixator in achondroplasia to determine whether callus types and shapes can predict the probability of callus fracture. The radiographs of 28 cases of femoral lengthening in 14 patients, 14 cases of callus fracture, and 14 cases without callus fracture were retrospectively analyzed by four observers and classified into different shapes and types in concordance with the Ru Li classification. The average lengthening of 9.4 cm (range 7.5-11.8 cm) was achieved, which was 41% (range 30-55%) of the original length and the average timing of callus fracture was 470 days (range 440-545 days) after surgery in the callus fracture group. While the average lengthening of 9.1 cm (range 8-9.7 cm) was achieved, this was 30% (range 28-32%) of the original length in the group of patients without callus fracture. The callus was atypically shaped, there was a 48% average (range 30-72%) reduction of the callus width compared with the natural width of the femur, and a lucent pathway was present in all cases of regenerate fracture. A lucent pathway was seen in all fracture cases with concave, lateral, and atypical shapes, and there was more than 30% lengthening and 30% reduction of the callus width compared with the natural width of the femur, which are the warning signs for regenerate fractures. These signs help the surgeon to predict the outcome and guide him in planning for any additional interventions. The Ru Li classification is an effective method for the evaluation of the chance of callus fracture.
A novel computer algorithm for modeling and treating mandibular fractures: A pilot study.
Rizzi, Christopher J; Ortlip, Timothy; Greywoode, Jewel D; Vakharia, Kavita T; Vakharia, Kalpesh T
2017-02-01
To describe a novel computer algorithm that can model mandibular fracture repair. To evaluate the algorithm as a tool to model mandibular fracture reduction and hardware selection. Retrospective pilot study combined with cross-sectional survey. A computer algorithm utilizing Aquarius Net (TeraRecon, Inc, Foster City, CA) and Adobe Photoshop CS6 (Adobe Systems, Inc, San Jose, CA) was developed to model mandibular fracture repair. Ten different fracture patterns were selected from nine patients who had already undergone mandibular fracture repair. The preoperative computed tomography (CT) images were processed with the computer algorithm to create virtual images that matched the actual postoperative three-dimensional CT images. A survey comparing the true postoperative image with the virtual postoperative images was created and administered to otolaryngology resident and attending physicians. They were asked to rate on a scale from 0 to 10 (0 = completely different; 10 = identical) the similarity between the two images in terms of the fracture reduction and fixation hardware. Ten mandible fracture cases were analyzed and processed. There were 15 survey respondents. The mean score for overall similarity between the images was 8.41 ± 0.91; the mean score for similarity of fracture reduction was 8.61 ± 0.98; and the mean score for hardware appearance was 8.27 ± 0.97. There were no significant differences between attending and resident responses. There were no significant differences based on fracture location. This computer algorithm can accurately model mandibular fracture repair. Images created by the algorithm are highly similar to true postoperative images. The algorithm can potentially assist a surgeon planning mandibular fracture repair. 4. Laryngoscope, 2016 127:331-336, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.
Beaton, Dorcas E; Mamdani, Muhammad; Zheng, Hong; Jaglal, Susan; Cadarette, Suzanne M; Bogoch, Earl R; Sale, Joanna E M; Sujic, Rebeka; Jain, Ravi
2017-12-01
We evaluated a system-wide impact of a health intervention to improve treatment of osteoporosis after a fragility fracture. The intervention consisted of assigning a screening coordinator to selected fracture clinics to identify, educate, and follow up with fragility fracture patients and inform their physicians of the need to evaluate bone health. Thirty-seven hospitals in the province of Ontario (Canada) were assigned a screening coordinator. Twenty-three similar hospitals were control sites. All hospitals had orthopedic services and handled moderate-to-higher volumes of fracture patients. Administrative health data were used to evaluate the impact of the intervention.Fragility fracture patients (≥50 years; hip, humerus, forearm, spine, or pelvis fracture) were identified from administrative health records. Cases were fractures treated at 1 of the 37 hospitals assigned a coordinator. Controls were the same types of fractures at the control sites. Data were assembled for 20 quarters before and 10 quarters after the implementation (from January 2002 to March 2010). To test for a shift in trends, we employed an interrupted time series analysis-a study design used to evaluate the longitudinal effects of interventions, through regression modelling. The primary outcome measure was bone mineral density (BMD) testing. Osteoporosis medication initiation and persistence rates were secondary outcomes in a subset of patients ≥66 years of age.A total of 147,071 patients were used in the analysis. BMD testing rates increased from 17.0% pre-intervention to 20.9% post-intervention at intervention sites (P < .01) compared with no change at control sites (14.9% and 14.9%, P = .33). Medication initiation improved significantly at intervention sites (21.6-23.97%; P = .02) but not at control sites (17.5-18.5%; P = .27). Persistence with bisphosphonates decreased at all sites, from 59.9% to 56.4% at intervention sites (P = .02) and more so from 62.3% to 54.2% at control sites (P < .01) using 50% proportion of days covered (PDC 50).Significant improvements in BMD testing and treatment initiation were observed after the initiation of a coordinator-based screening program to improve osteoporosis management following fragility fracture.
Beaton, Dorcas E.; Mamdani, Muhammad; Zheng, Hong; Jaglal, Susan; Cadarette, Suzanne M.; Bogoch, Earl R.; Sale, Joanna E. M.; Sujic, Rebeka; Jain, Ravi
2017-01-01
Abstract We evaluated a system-wide impact of a health intervention to improve treatment of osteoporosis after a fragility fracture. The intervention consisted of assigning a screening coordinator to selected fracture clinics to identify, educate, and follow up with fragility fracture patients and inform their physicians of the need to evaluate bone health. Thirty-seven hospitals in the province of Ontario (Canada) were assigned a screening coordinator. Twenty-three similar hospitals were control sites. All hospitals had orthopedic services and handled moderate-to-higher volumes of fracture patients. Administrative health data were used to evaluate the impact of the intervention. Fragility fracture patients (≥50 years; hip, humerus, forearm, spine, or pelvis fracture) were identified from administrative health records. Cases were fractures treated at 1 of the 37 hospitals assigned a coordinator. Controls were the same types of fractures at the control sites. Data were assembled for 20 quarters before and 10 quarters after the implementation (from January 2002 to March 2010). To test for a shift in trends, we employed an interrupted time series analysis—a study design used to evaluate the longitudinal effects of interventions, through regression modelling. The primary outcome measure was bone mineral density (BMD) testing. Osteoporosis medication initiation and persistence rates were secondary outcomes in a subset of patients ≥66 years of age. A total of 147,071 patients were used in the analysis. BMD testing rates increased from 17.0% pre-intervention to 20.9% post-intervention at intervention sites (P < .01) compared with no change at control sites (14.9% and 14.9%, P = .33). Medication initiation improved significantly at intervention sites (21.6–23.97%; P = .02) but not at control sites (17.5–18.5%; P = .27). Persistence with bisphosphonates decreased at all sites, from 59.9% to 56.4% at intervention sites (P = .02) and more so from 62.3% to 54.2% at control sites (P < .01) using 50% proportion of days covered (PDC 50). Significant improvements in BMD testing and treatment initiation were observed after the initiation of a coordinator-based screening program to improve osteoporosis management following fragility fracture. PMID:29310418
Mortality Following Periprosthetic Proximal Femoral Fractures Versus Native Hip Fractures.
Boylan, Matthew R; Riesgo, Aldo M; Paulino, Carl B; Slover, James D; Zuckerman, Joseph D; Egol, Kenneth A
2018-04-04
The number of periprosthetic proximal femoral fractures is expected to increase with the increasing prevalence of hip arthroplasties. While native hip fractures have a well-known association with mortality, there are currently limited data on this outcome among the subset of patients with periprosthetic proximal femoral fractures. Using the New York Statewide Planning and Research Cooperative System, we identified patients from 60 to 99 years old who were admitted to a hospital in the state with a periprosthetic proximal femoral fracture (n = 1,655) or a native hip (femoral neck or intertrochanteric) fracture (n = 97,231) between 2006 and 2014. Within the periprosthetic fracture cohort, the indication for the existing implant was not available in the data set. We used mixed-effects regression models to compare mortality at 1 and 6 months and 1 year for periprosthetic compared with native hip fractures. The risk of mortality for patients who sustained a periprosthetic proximal femoral fracture was no different from that for patients who sustained a native hip fracture at 1 month after injury (3.2% versus 4.6%; odds ratio [OR], 0.90; 95% confidence interval [CI], 0.68 to 1.19; p = 0.446), but was lower at 6 months (3.8% versus 6.5%; OR, 0.74; 95% CI, 0.57 to 0.95; p = 0.020) and 1 year (9.7% versus 15.9%; OR, 0.71; 95% CI, 0.60 to 0.85; p < 0.001). Among periprosthetic proximal femoral fractures, factors associated with a significantly increased risk of mortality at 1 year included advanced age, male sex, and higher Deyo comorbidity scores. In the acute phase, any type of hip fracture appears to confer a similar risk of death. Over the long term, however, periprosthetic proximal femoral fractures are associated with lower mortality rates than native hip fractures, even after accounting for age and comorbidities. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Yasa, E; Arslan, H; Yasa, B; Akcay, M; Alsancak, M; Hatirli, H
2017-10-01
To evaluate the effect of various materials as intra-orifice barriers on the force required fracture roots. One hundred-thirty five mandibular premolars were decoronated and prepared up to size #40. The root canals were filled and randomly divided into two control and seven experimental groups (n = 15), as follows: Positive control group (the intra-orifice barrier cavity was not prepared), negative control group (the intra-orifice barrier cavity was prepared, but not filled), filling using glass ionomer cement, nano-hybrid composite resin, short fiber-reinforced composite, bulk-fill flowable composite, MTA Angelus, Micro Mega MTA or Biodentine. A fracture strength test was performed, and the data were analyzed using one-way ANOVA and Tukey's post hoc tests. Nano-hybrid composite, short fiber-reinforced composite, bulk-fill flow able composite, and glass ionomer cement increased the force required fracture the roots compared to the positive and negative control groups (P < 0.05). While MTA groups did not increase the force required fracture the roots compared to the control groups, Biodentine increased significantly. Within the limitations of the present study, the use of nano-hybrid composite, short fiber-reinforced composite, bulk-fill flowable composite, and glass ionomer cement as an intra-orifice barrier may be useful in reinforcing roots. MTA placement (MTA Angelus or Micro Mega MTA) did not significantly increase the fracture resistance of endodontically treated roots compared to the control groups, however Biodentine did.
Turbine Engine Hot Section Technology, 1984
NASA Technical Reports Server (NTRS)
1984-01-01
Presentations were made concerning the hot section environment and behavior of combustion liners, turbine blades, and waves. The presentations were divided into six sessions: instrumentation, combustion, turbine heat transfer, structural analysis, fatigue and fracture, and surface properties. The principal objective of each session was to disseminate research results to date, along with future plans. Topics discussed included modeling of thermal and fluid flow phenomena, structural analysis, fatigue and fracture, surface protective coatings, constitutive behavior, stress-strain response, and life prediction methods.
Ma, Deqiong; Jones, Graeme
2003-11-01
The effect of physical activity on upper limb fractures was examined in this population-based case control study with 321 age- and gender-matched pairs. Sports participation increased fracture risk in boys and decreased risk in girls. Television viewing had a deleterious dose response association with wrist and forearm fractures while light physical activity was protective. The aim of this population-based case control study was to examine the association between television, computer, and video viewing; types and levels of physical activity; and upper limb fractures in children 9-16 years of age. A total of 321 fracture cases and 321 randomly selected individually matched controls were studied. Television, computer, and video viewing and types and levels of physical activity were determined by interview-administered questionnaire. Bone strength was assessed by DXA and metacarpal morphometry. In general, sports participation increased total upper limb fracture risk in boys and decreased risk in girls. Gender-specific risk estimates were significantly different for total, contact, noncontact, and high-risk sports participation as well as four individual sports (soccer, cricket, surfing, and swimming). In multivariate analysis, time spent television, computer, and video viewing in both sexes was positively associated with wrist and forearm fracture risk (OR 1.6/category, 95% CI: 1.1-2.2), whereas days involved in light physical activity participation decreased fracture risk (OR 0.8/category, 95% CI: 0.7-1.0). Sports participation increased hand (OR 1.5/sport, 95% CI: 1.1-2.0) and upper arm (OR 29.8/sport, 95% CI: 1.7-535) fracture risk in boys only and decreased wrist and forearm fracture risk in girls only (OR 0.5/sport, 95% CI: 0.3-0.9). Adjustment for bone density and metacarpal morphometry did not alter these associations. There is gender discordance with regard to sports participation and fracture risk in children, which may reflect different approaches to sport. Importantly, television, computer, and video viewing has a dose-dependent association with wrist and forearm fractures, whereas light physical activity is protective. The mechanism is unclear but may involve bone-independent factors, or less likely, changes in bone quality not detected by DXA or metacarpal morphometry.
Patsch, Janina M; Li, Xiaojuan; Baum, Thomas; Yap, Samuel P; Karampinos, Dimitrios C; Schwartz, Ann V; Link, Thomas M
2013-08-01
The goal of this magnetic resonance (MR) imaging study was to quantify vertebral bone marrow fat content and composition in diabetic and nondiabetic postmenopausal women with fragility fractures and to compare them with nonfracture controls with and without type 2 diabetes mellitus. Sixty-nine postmenopausal women (mean age 63 ± 5 years) were recruited. Thirty-six patients (47.8%) had spinal and/or peripheral fragility fractures. Seventeen fracture patients were diabetic. Thirty-three women (52.2%) were nonfracture controls. Sixteen women were diabetic nonfracture controls. To quantify vertebral bone marrow fat content and composition, patients underwent MR spectroscopy (MRS) of the lumbar spine at 3 Tesla. Bone mineral density (BMD) was determined by dual-energy X-ray absorptiometry (DXA) of the hip and lumbar spine (LS) and quantitative computed tomography (QCT) of the LS. To evaluate associations of vertebral marrow fat content and composition with spinal and/or peripheral fragility fractures and diabetes, we used linear regression models adjusted for age, race, and spine volumetric bone mineral density (vBMD) by QCT. At the LS, nondiabetic and diabetic fracture patients had lower vBMD than controls and diabetics without fractures (p = 0.018; p = 0.005). However, areal bone mineral density (aBMD) by DXA did not differ between fracture and nonfracture patients. After adjustment for age, race, and spinal vBMD, the prevalence of fragility fractures was associated with -1.7% lower unsaturation levels (confidence interval [CI] -2.8% to -0.5%, p = 0.005) and +2.9% higher saturation levels (CI 0.5% to 5.3%, p = 0.017). Diabetes was associated with -1.3% (CI -2.3% to -0.2%, p = 0.018) lower unsaturation and +3.3% (CI 1.1% to 5.4%, p = 0.004) higher saturation levels. Diabetics with fractures had the lowest marrow unsaturation and highest saturation. There were no associations of marrow fat content with diabetes or fracture. Our results suggest that altered bone marrow fat composition is linked with fragility fractures and diabetes. MRS of spinal bone marrow fat may therefore serve as a novel tool for BMD-independent fracture risk assessment. Copyright © 2013 American Society for Bone and Mineral Research.
Nemcok, M.; Moore, J.N.; Allis, R.; McCulloch, J.
2004-01-01
Karaha-Telaga Bodas, a vapour-dominated geothermal system located in an active volcano in western Java, is penetrated by more than two dozen deep geothermal wells reaching depths of 3 km. Detailed paragenetic and fluid-inclusion studies from over 1000 natural fractures define the liquid-dominated, transitional and vapour-dominated stages in the evolution of this system. The liquid-dominated stage was initiated by ashallow magma intrusion into the base of the volcanic cone. Lava and pyroclastic flows capped a geothermal system. The uppermost andesite flows were only weakly fractured due to the insulating effect of the intervening altered pyroclastics, which absorbed the deformation. Shear and tensile fractures that developed were filled with carbonates at shallow depths, and by quartz, epidote and actinolite at depths and temperatures over 1 km and 300??C. The system underwent numerous cycles of overpressuring, documented by subhorizontal tensile fractures, anastomosing tensile fracture patterns and implosion breccias. The development of the liquidsystem was interrupted by a catastrophic drop in fluid pressures. As the fluids boiled in response to this pressure drop, chalcedony and quartz were selectively deposited in fractures that had the largest apertures and steep dips. The orientations of these fractures indicate that the escaping overpressured fluids used the shortest possible paths to the surface. Vapour-dominated conditions were initiated at this time within a vertical chimney overlying the still hot intrusion. As pressures declined, these conditions spread outward to form the marginal vapour-dominated region encountered in the drill holes. Downward migration of the chimney, accompanied by growth of the marginal vapour-dominated regime, occurred as the intrusion cooled and the brittle-ductile transition migrated to greater depths. As the liquids boiled off, condensate that formed at the top of the vapour-dominated zone percolated downward and low-salinity meteoric water entered the marginal parts of the system. Calcite, anhydrite and fluorite precipitated in fractures on heating. Progressive sealing of the fractures resulted in the downward migration of the cap rock. In response to decreased pore pressure in the expanding vapour zone, walls of the fracture system within the vapour-dominated reservoir progressively collapsed. It left only residual permeability in the remaining fracture volume, with apertures supported only by asperities or propping breccia. In places where normal stresses acting on the fracture walls exceeded the compressive strength of the wall rock, the fractures have completely collapsed. Fractures within the present-day cap rock include strike- and oblique-slip faults, normal faults and tensile fractures, all controlled by a strike-slip stress regime. The reservoir is characterized by normal faults and tensile fractures controlled by a normal-fault stress regime. The fractures show no evidence that the orientation of the stress field has changed since fracture propagation began. Fluid migration in the lava and pyroclastic flows is controlled by fractures. Matrix permeability controls fluid flow in the sedimentary sections of the reservoir. Productive fractures are typically roughly perpendicular to the minimum compressive stress, ??3, and are prone to slip and dilation within the modern stress regime. ?? The Geological Society of London 2004.
Sensitivity Analysis of the Bone Fracture Risk Model
NASA Technical Reports Server (NTRS)
Lewandowski, Beth; Myers, Jerry; Sibonga, Jean Diane
2017-01-01
Introduction: The probability of bone fracture during and after spaceflight is quantified to aid in mission planning, to determine required astronaut fitness standards and training requirements and to inform countermeasure research and design. Probability is quantified with a probabilistic modeling approach where distributions of model parameter values, instead of single deterministic values, capture the parameter variability within the astronaut population and fracture predictions are probability distributions with a mean value and an associated uncertainty. Because of this uncertainty, the model in its current state cannot discern an effect of countermeasures on fracture probability, for example between use and non-use of bisphosphonates or between spaceflight exercise performed with the Advanced Resistive Exercise Device (ARED) or on devices prior to installation of ARED on the International Space Station. This is thought to be due to the inability to measure key contributors to bone strength, for example, geometry and volumetric distributions of bone mass, with areal bone mineral density (BMD) measurement techniques. To further the applicability of model, we performed a parameter sensitivity study aimed at identifying those parameter uncertainties that most effect the model forecasts in order to determine what areas of the model needed enhancements for reducing uncertainty. Methods: The bone fracture risk model (BFxRM), originally published in (Nelson et al) is a probabilistic model that can assess the risk of astronaut bone fracture. This is accomplished by utilizing biomechanical models to assess the applied loads; utilizing models of spaceflight BMD loss in at-risk skeletal locations; quantifying bone strength through a relationship between areal BMD and bone failure load; and relating fracture risk index (FRI), the ratio of applied load to bone strength, to fracture probability. There are many factors associated with these calculations including environmental factors, factors associated with the fall event, mass and anthropometric values of the astronaut, BMD characteristics, characteristics of the relationship between BMD and bone strength and bone fracture characteristics. The uncertainty in these factors is captured through the use of parameter distributions and the fracture predictions are probability distributions with a mean value and an associated uncertainty. To determine parameter sensitivity, a correlation coefficient is found between the sample set of each model parameter and the calculated fracture probabilities. Each parameters contribution to the variance is found by squaring the correlation coefficients, dividing by the sum of the squared correlation coefficients, and multiplying by 100. Results: Sensitivity analyses of BFxRM simulations of preflight, 0 days post-flight and 365 days post-flight falls onto the hip revealed a subset of the twelve factors within the model which cause the most variation in the fracture predictions. These factors include the spring constant used in the hip biomechanical model, the midpoint FRI parameter within the equation used to convert FRI to fracture probability and preflight BMD values. Future work: Plans are underway to update the BFxRM by incorporating bone strength information from finite element models (FEM) into the bone strength portion of the BFxRM. Also, FEM bone strength information along with fracture outcome data will be incorporated into the FRI to fracture probability.
NASA Technical Reports Server (NTRS)
Ehret, R. M.
1974-01-01
The concepts explored in a state of the art review of those engineering fracture mechanics considered most applicable to the space shuttle vehicle include fracture toughness, precritical flaw growth, failure mechanisms, inspection methods (including proof test logic), and crack growth predictive analysis techniques.
In vivo effect of shock-waves on the healing of fractured bone.
Augat, P; Claes, L; Suger, G
1995-10-01
In a controlled animal experiment we attempted to clarify the question of whether there is a stimulating effect of extracorporeal shock-waves on the repair process of fractured long bones. As a fracture model we used an osteotomy in the diaphysis of the ovine tibia and an external fixation device. Shock-wave treatment at two levels of intensity and with four different numbers of applied shocks was performed with an electromagnetic acoustic source. Healing of the osteotomized bone was evaluated by biomechanical and radiological investigations on the whole bone as well as on bone sections from areas of the fracture gap and the periosteal fracture callus. We found a non-significant tendency to deterioration of the fracture healing with increasing shock-wave intensities. The study of treatment parameters led neither to significantly different biomechanical outcomes nor to altered radiological results in comparison to the untreated control group. RELEVANCE:--While we cannot comment upon the effectiveness of extracorporeal shock-waves in the delayed treatment of fractures or pseudarthrosis, our results suggest that shock-waves have no beneficial effect in acute fracture repair.
A unified technology plan for fatigue and fracture design
NASA Technical Reports Server (NTRS)
Hardrath, H. F.
1973-01-01
An integrated research program is proposed that seeks to improve the technology of designing against fatigue and fracture and to develop a computerized capability for assessing the adequacy of a given design. Both fatigue life prediction and damage tolerance considerations are incorporated. The research for each of these considerations is organized to account for material behavior, the effect of structural configurations, the cumulative effects of the operating loadings, and for the effects of environment - temperature and corrosion. The goal is to achieve a viable fatigue and fracture design procedure for any practical problem. The overall program is outlined, assessments are made of the state of the art, subgoals are proposed, and means for achieving them are suggested.
Admittance Survey of Type 1 Coronae on Venus: Implications for Elastic Thickness
NASA Technical Reports Server (NTRS)
Hoogenboom, T.; Smrekar, S. E.; Anderson, F. S.; Houseman, G.
2003-01-01
Coronae are volcano-tectonic features on Venus which range from 60km to 2600km and are defined by their nearly circular patterns of fractures. Type 1 (regular) coronae are classified as having >50% complete fracture annuli. Previous work has examined the factors controlling the morphology, size, and fracture pattern of coronae, using lithospheric properties, loading signature and geologic characteristics. However, these studies have been limited to Type 2 (topographic) coronae (e.g. coronaes with <50% fracture annuli), and the factors controlling the formation of Type 1 coronae remain poorly understood. In this study, we apply the methodology of to survey the admittance signature for Type 1 coronae to determine the controlling parameters which govern Type 1 coronae formation.
Chen, Fu-hong; Chen, Ze; Duan, Heng-qiong; Wan, Zhong-xian
2008-10-01
To observe the influence of earthquake crush injury on postoperative wound healing of extremity fractures. The study involved 85 patients with extremities fracture underwent internal fixation operation in 3 group, including 28 earthquake casualties with crush injuries in observation group, 27 earthquake casualties without crush injuries in control I group and 30 local patients during the same period in control II group. Urine routine, blood creatine kinase (CK) and wound conditions of patients in 3 groups were observed respectively. There was no significant difference in Urine routine and blood CK between 3 groups and was significant difference in wound conditions between observation group and each control group. Earthquake crush injuries can influence the postoperative wound healing of extremity fractures.
Analysis of horse race videos to identify intra-race risk factors for fatal distal limb fracture.
Parkin, T D H; Clegg, P D; French, N P; Proudman, C J; Riggs, C M; Singer, E R; Webbon, P M; Morgan, K L
2006-04-17
The objective of this study was to identify risk factors, during racing, associated with imminent fatal distal limb fracture in Thoroughbreds. One hundred and nine cases of fatal distal limb fracture were identified from all 59 UK racecourses over a 2-year period (February 1999-January 2001). Three uninjured control horses were randomly selected from the same race as the case horse. Videos of races in which fractures occurred were viewed using a defined protocol. Fractures in flat races occurred at any time during the race, whereas 74% (45/61) of cases in national hunt type races occurred in the second half of races. More than 75% (79/103) of cases were spontaneous, i.e. there was no obvious external influence such as a fall at a fence or collision with another horse. Sixty-six percent (44/67) of horses, sustaining a forelimb fracture, fractured the forelimb they were using as lead leg at the time of fracture. When case and control horses were compared, horses that were: (a) making good progress through the race, (b) reluctant to start and (c) received encouragement in the final 10s before the time of fracture, were more likely to sustain a fracture.
Influence of fracture extension on in-situ stress in tight reservoir
NASA Astrophysics Data System (ADS)
Zhang, Yongping; Wei, Xu; Zhang, Ye; Xing, Libo; Xu, Jianjun
2018-01-01
Currently, hydraulic fracturing is an important way to develop low permeability reservoirs. The fractures produced during the fracturing process are the main influencing factors of changing in-situ stress. In this paper, the influence of fracture extension on in-situ stress is studied by establishing a mathematical model to describe the relationship between fracture length and in-situ stress. The results show that the growth rate gradually decreases after the fracture reaches a certain length with the increase of fracturing time; the continuous extension of the fracture is the main factor to change the in-situ stress. In order to reduce the impact on the subsequent fracture extension due to the changing of in-situ stress, controlling fracturing time and fracture length without affecting the stimulated reservoir effect is an important way. The results presented in this study can effectively reduce the impact of changing of in-situ stress on subsequent fracturing construction.
A controlled trial of glutamine effects on bone healing.
Polat, Onur; Kilicoglu, Sibel Serin; Erdemli, Esra
2007-01-01
Glutamine is considered a nonessential amino acid, but it may be conditionally essential in patients with catabolic conditions. For centuries, researchers have looked for ways to promote and accelerate fracture healing. This controlled animal study examines the effects of glutamine on fracture healing. The left tibias of 10 standardized albino rats were broken at the distal third to produce a closed fracture. L-glutamine/L-alanyl solution (2.0 mL/kg) was administered through the tail veins of half the rats for the first 7 d, and physiologic serum alone was given to the control group. On the 21st day, all rats were euthanized and their left legs removed; after histologic observation, the tibias were examined under light microscopy. In the glutamine-injected group, development of primary callus was quicker and more regular than in the control group. The control group produced insufficient fibrous callus, and the glutamine group attained formed cartilaginous callus. Glutamine was noted to have positive effects on healing of traumatically fractured bone through attainment of positive nitrogen balance. This effect was minimal in enhancing the quality of fracture healing under conditions of stress, but some effect was noted on the speed of healing. Further research is needed in this area.
2014-01-01
Background Fractures lead to reduced physical function and quality of life (QOL), but little is known about postmenopausal women with osteopenia and a healed wrist fracture. The purpose was to evaluate physical function in terms of quadriceps strength, dynamic balance, physical capacity and QOL in postmenopausal women with osteopenia and a healed wrist fracture compared to a matched, healthy control group with no previous fracture. Methods Eighteen postmenopausal women with osteopenia (patients) (mean age 59.1 years, range 54 – 65) and a healed wrist fracture were matched to 18 healthy control subjects on age (mean age 58.5 years, range 51 – 65), height, weight and body mass index (BMI). We measured quadriceps strength at 60°/sec and at 180°/sec with Biodex 6000, dynamic balance with the Four Square Step Test (FSST), physical capacity with the six-minute walk test (6MWT) followed by the Borg’s scale (BS), and QOL with the Short Form 36 (SF-36), bone mineral density (BMD) with dual x-ray absorptiometry (DXA) and physical activity level with the Physical Activity Scale for the Elderly. Results The patients had 17.6% lower quadriceps strength at 60°/sec (p = 0.025) at left limb and 18.5% at 180°/sec (p = 0.016) at right limb, and 21% lower at 180°/sec (p = 0.010) at left limb compared to the controls. Impaired performance for the patients was found with 2.4 seconds (p = 0.002) on the FSST, 74 metres (p < 0.001) on the 6MWT, and 1.4 points (p = 0.003) on the BS compared to the controls. The patients scored lower on the sub-scales on the SF-36 role limitations-physical (p = 0.014), bodily pain (p = 0.025) and vitality (p = 0.015) compared to the controls. Conclusions The patients with osteopenia and a healed wrist fracture scored significantly lower on quadriceps strength, dynamic balance, physical capacity and QOL compared to the matched controls. Greater focus should be put on this patient group in terms of rehabilitation and early prevention of subsequent fractures. PMID:25086601
Retardation of organo-bromides in a fractured chalk aquitard.
Ezra, Shai; Feinstein, Shimon; Yakirevich, Alex; Adar, Eilon; Bilkis, Itzhak
2006-08-10
This study investigates the mechanisms controlling the distribution of 3-bromo-2,2-bis(bromomethyl)propanol (TBNPA) and 2,2-bis(bromomethyl)propan-1,3-diol (DBNPG) in a fractured chalk aquitard. An extensive monitoring program showed a systematic decrease in the TBNPA/DBNPG ratio with distance from the contamination source. Sorption of TBNPA on the white and/or gray chalks comprising the aquitard is approximately one order of magnitude greater than that of DBNPG. This results in more efficient removal of TBNPA from the fracture into the porous matrix and thus decreases the TBNPA/DBNPG ratio in the fracture water. Mathematical modeling of solute transport in the fracture domain illustrates the probable importance of sorption in controlling the spatial variation in TBNPA and DBNPG ratio.
Visit from JAXA to NASA MSFC: The Engines Element & Ideas for Collaboration
NASA Technical Reports Server (NTRS)
Greene, William D.
2013-01-01
System Design, Development, and Fabrication: Design, develop, and fabricate or procure MB-60 component hardware compliant with the imposed technical requirements and in sufficient quantities to fulfill the overall MB-60 development effort. System Development, Assembly, and Test: Manage the scope of the development, assembly, and test-related activities for MB-60 development. This scope includes engine-level development planning, engine assembly and disassembly, test planning, engine testing, inspection, anomaly resolution, and development of necessary ground support equipment and special test equipment. System Integration: Provide coordinated integration in the realms of engineering, safety, quality, and manufacturing disciplines across the scope of the MB-60 design and associated products development Safety and Mission Assurance, structural design, fracture control, materials and processes, thermal analysis. Systems Engineering and Analysis: Manage and perform Systems Engineering and Analysis to provide rigor and structure to the overall design and development effort for the MB-60. Milestone reviews, requirements management, system analysis, program management support Program Management: Manage, plan, and coordinate the activities across all portions of the MB-60 work scope by providing direction for program administration, business management, and supplier management.
Hansen, Ann-Brit E; Gerstoft, Jan; Kronborg, Gitte; Larsen, Carsten S; Pedersen, Court; Pedersen, Gitte; Obel, Niels
2012-01-28
To compare fracture risk in persons with and without HIV infection and to examine the influence of highly active antiretroviral therapy (HAART) initiation on risk of fracture. Population-based nationwide cohort study using Danish registries. Outcome measures were time to first fracture at any site, time to first low-energy and high-energy fracture in HIV-infected patients (n = 5306) compared with a general population control cohort (n = 26 530) matched by sex and age during the study period 1995-2009. Cox regression analyses were used to estimate incidence rate ratios (IRRs). HIV-infected patients had increased risk of fracture [IRR 1.5, 95% confidence interval (CI) 1.4-1.7] compared with population controls. The relative risk was lower in HIV-monoinfected patients (IRR 1.3, 95% CI 1.2-1.4) than in HIV/hepatitis C virus (HCV)-coinfected patients (IRR 2.9, 95% CI 2.5-3.4).Both HIV-monoinfected and HIV/HCV-coinfected patients had increased risk of low-energy fracture, IRR of 1.6 (95% CI 1.4-1.8) and 3.8 (95% CI 3.0-4.9). However, only HIV/HCV-coinfected patients had increased risk of high-energy fracture, IRR of 2.4 (95% CI 2.0-2.9). Among HIV-monoinfected patients the risk of low-energy fracture was only significantly increased after HAART exposure, IRR of 1.8 (95% CI 1.5-2.1). The increased risk in HAART-exposed patients was not associated with CD4 cell count, prior AIDS, tenofovir or efavirenz exposure, but with comorbidity and smoking. HIV-infected patients had increased risk of fracture compared with population controls. Among HIV-monoinfected patients the increased risk was observed for low-energy but not for high-energy fractures, and the increased risk of low-energy fracture was only observed in HAART-exposed patients.
NASA Astrophysics Data System (ADS)
Benaafi, Mohammed; Hariri, Mustafa; Abdullatif, Osman; Makkawi, Mohammed; Korvin, Gabor
2016-04-01
The Cambro-Permian Wajid Group, SW Saudi Arabia, is the main groundwater aquifer in Wadi Al-Dawasir and Najran areas. In addition, it has a reservoir potentiality for oil and natural gas in Rub' Al-Khali Basin. Wajid Group divided into four formations, ascending Dibsiyah, Sanamah, Khussyayan and Juwayl. They are mainly sandstone and exposed in an area extend from Wadi Al-Dawasir southward to Najran city and deposited within fluvial, shallow marine and glacial environments. This study aims to investigate the sedimentological and stratigraphic controls on the distribution of natural fractures within Wajid Group outcrops. A scanline sampling method was used to study the natural fracture network within Wajid Group outcrops, where the natural fractures were measured and characterized in 12 locations. Four regional natural fracture sets were observed with mean strikes of 050o, 075o, 345o, and 320o. Seven lithofacies characterized the Wajid Group at these locations and include fine-grained sandstone, coarse to pebbly sandstone, cross-bedded sandstone, massive sandstone, bioturbated sandstone, conglomerate sandstone, and conglomerate lithofacies. We found that the fine-grained and small scale cross-bedded sandstones lithofacies are characterized by high fracture intensity. In contrast, the coarse-grained sandstone and conglomerate lithofacies have low fracture intensity. Therefore, the relative fracture intensity and spacing of natural fractures within Wajid Group in the subsurface can be predicted by using the lithofacies and their depositional environments. In terms of stratigraphy, we found that the bed thickness and the stratigraphic architecture are the main controls on fractures intensity. The outcomes of this study can help to understand and predict the natural fracture distribution within the subsurface fractured sandstone hosting groundwater and hydrocarbon in Wajid and Rub' Al-Khali Basins. Hence, the finding of this study might help to explore and develop the groundwater and hydrocarbon resources in the subsurface.
Hald, Jannie D; Evangelou, Evangelos; Langdahl, Bente L; Ralston, Stuart H
2015-05-01
Bisphosphonates are widely used off-label in the treatment of patients with osteogenesis imperfecta (OI) with the intention of reducing the risk of fracture. Although there is strong evidence that bisphosphonates increase bone mineral density in osteogenesis imperfecta, the effects on fracture occurrence have been inconsistent. The aim of this study was to gain a better insight into the effects of bisphosphonate therapy on fracture risk in patients with osteogenesis imperfecta by conducting a meta-analysis of randomized controlled trials in which fractures were a reported endpoint. We searched Medline, Embase, and the Cochrane Central Register of Controlled Trials in which the effects of bisphosphonates on fracture risk in osteogenesis imperfecta were compared with placebo and conducted a meta-analysis of these studies using standard methods. Heterogeneity was assessed using the I2 statistic. Six eligible studies were identified involving 424 subjects with 751 patient-years of follow-up. The proportion of patients who experienced a fracture was not significantly reduced by bisphosphonate therapy (Relative Risk [RR] = 0.83 [95% confidence interval 0.69-1.01], p = 0.06) with no heterogeneity between studies (I2 = 0). The fracture rate was reduced by bisphosphonate treatment when all studies were considered (RR = 0.71 [0.52-0.96], p = 0.02), but with considerable heterogeneity (I2 = 36%) explained by one study where a small number of patients in the placebo group experienced a large number of fractures. When this study was excluded, the effects of bisphosphonates on fracture rate was not significant (RR = 0.79 [0.61-1.02], p = 0.07, I2 = 0%). We conclude that the effects of bisphosphonates on fracture prevention in osteogenesis imperfecta are inconclusive. Adequately powered trials with a fracture endpoint are needed to further investigate the risks and benefits of bisphosphonates in this condition. © 2014 American Society for Bone and Mineral Research.
NASA Astrophysics Data System (ADS)
Cathles, L. M.; Sanford, W. E.; Hawkins, A.; Li, Y. V.
2017-12-01
The nature of flow in fractured porous media is important to almost all subsurface processes including oil and gas recovery, contaminant transport and remediation, CO2 sequestration, and geothermal heat extraction. One would like to know, under flowing conditions, the flow volume, surface area, effective aperture, and rectilinear spacing of fractures in a representative volume of rock away from the well bore, but no methods currently allow acquisition of this data. It could, however, be collected by deploying inert tracers with a wide range of aqueous diffusion constants (e.g., rapidly diffusing heat to non-diffusing nanoparticle) in the following fashion: The flow volume is defined by the heated volume measured by resistivity surveys. The fracture volume within this flow volume is indicate by the nanoparticle transit time. The average fracture spacing is indicated by the evolving thermal profile in the monitor and the production wells (measured by fiber optic cable), and by the retention of absorbing tracers. The average fracture aperture is determined by permeability measurements and the average fracture separation. We have proposed a field test to redundantly measure these fracture parameters in the fractured Dakota Sandstone where it approaches the surface in Ft Collins, Colorado. Five 30 m deep wells (an injection, production, and 3 monitor wells) cased to 20 m are proposed. The experiments will involve at least 9 different tracers. The planned field test and its potential significance will be described.
Hip fractures: incidence, risk factors, energy absorption, and prevention.
Lauritzen, J B
1996-01-01
The present review summarizes the pathogenic mechanisms leading to hip fracture based on epidemiological, experimental, and controlled clinical studies. The estimated lifetime risk of hip fracture is about 14% in postmenopausal women and 6% in men. The incidence of hip fractures increases exponentially with aging, but the time trend in increasing age-specific incidence may finally reach a plateau. Postmenopausal women suffering earlier non-hip fractures have an increased risk of later hip fracture. The relative risk is highest within the first years following the fracture. Nursing home residents have a high risk of hip fracture (annual rate of 5-6%), and their incidence of falls is about 1.5 falls/person per year. Most hip fractures are a result of a direct trauma against the hip. The incidence of falls on the hip among nursing home residents is about 0.29 falls/person per year and about 20% of these traumas lead to hip fracture. Women with hip fractures have a lower body weight compared with controls, and they may also have less soft tissue covering the hip, even when adjusted for body mass index, indicating a more android body habitus. Experimental studies show that the passive energy absorption in soft tissue covering the hip may influence the risk of hip fracture and be an important determinant for the development of hip fracture, perhaps even more important than bone strength. External hip protectors were developed and tested in an open randomized nursing home study. The rate of hip fracture was reduced by 50%, corresponding to 9 of 247 residents saved from sustaining a hip fracture. This review points to the essentials in the development of hip fracture: risk of fall; type of fall; type of impact; energy absorption; and last, bone strength, which is the final permissive factor leading to hip fracture. Risk estimation and prevention of hip fracture may prove realistic when these issues are taken into consideration.
Jones, Christopher; Aqil, Adeel; Clarke, Susannah; Cobb, Justin P
2015-09-01
Short femoral stems for uncemented total hip arthroplasty have been introduced as a safe alternative to traditional longer stem designs. However, there has been little biomechanical examination of the effects of stem length on complications of surgery. This study aims to examine the effect of femoral stem length on torsional resistance to peri-prosthetic fracture. We tested 16 synthetic and two paired cadaveric femora. Specimens were implanted and then rapidly rotated until fracture to simulate internal rotation on a planted foot, as might occur during stumbling. 3D planning software and custom-printed 3D cutting guides were used to enhance the accuracy and consistency of our stem insertion technique. Synthetic femora implanted with short stems fractured at a significantly higher torque (27.1 vs. 24.2 Nm, p = 0.03) and angle (30.3° vs. 22.3°, p = 0.002) than those implanted with long stems. Fracture patterns of the two groups were different, but showed remarkable consistency within each group. These characteristic fracture patterns were closely replicated in the pair of cadaveric femora. This new short-stemmed press-fit femoral component allows more femoral flexibility and confers a higher resistance to peri-prosthetic fracture from torsional forces than long stems.
Association between Nurse Staffing and In-Hospital Bone Fractures: A Retrospective Cohort Study.
Morita, Kojiro; Matsui, Hiroki; Fushimi, Kiyohide; Yasunaga, Hideo
2017-06-01
To determine if sufficient nurse staffing reduced in-hospital fractures in acute care hospitals. The Japanese Diagnosis Procedure Combination inpatient (DPC) database from July 2010 to March 2014 linked with the Surveys for Medical Institutions. We conducted a retrospective cohort study to examine the association of inpatient nurse-to-occupied bed ratio (NBR) with in-hospital fractures. Multivariable logistic regression with generalized estimating equations was performed, adjusting for patient characteristics and hospital characteristics. We identified 770,373 patients aged 50 years or older who underwent planned major surgery for some forms of cancer or cardiovascular diseases. We used ICD-10 codes and postoperative procedure codes to identify patients with in-hospital fractures. Hospital characteristics were obtained from the "Survey of Medical Institutions and Hospital Report" and "Annual Report for Functions of Medical Institutions." Overall, 662 (0.09 percent) in-hospital fractures were identified. Logistic regression analysis showed that the proportion of in-hospital fractures in the group with the highest NBR was significantly lower than that in the group with the lowest NBR (adjusted odd ratios, 0.67; 95 percent confidence interval, 0.44-0.99; p = .048). Sufficient nurse staffing may be important to reduce postsurgical in-hospital fractures in acute care hospitals. © Health Research and Educational Trust.
DOE Office of Scientific and Technical Information (OSTI.GOV)
George Witter; Robert Knoll; William Rehm
2005-09-29
This project was undertaken to demonstrate that oil and gas can be drilled and produced safely and economically from a fractured Monterey reservoir in the Santa Maria Basin of California by employing horizontal wellbores and underbalanced drilling technologies. Two vertical wells were previously drilled in this area with heavy mud and conventional completions; neither was commercially productive. A new well was drilled by the project team in 2004 with the objective of accessing an extended length of oil-bearing, high-resistivity Monterey shale via a horizontal wellbore, while implementing managed-pressure drilling (MPD) techniques to avoid formation damage. Initial project meetings were conductedmore » in October 2003. The team confirmed that the demonstration well would be completed open-hole to minimize productivity impairment. Following an overview of the geologic setting and local field experience, critical aspects of the application were identified. At the pre-spud meeting in January 2004, the final well design was confirmed and the well programming/service company requirements assigned. Various design elements were reduced in scope due to significant budgetary constraints. Major alterations to the original plan included: (1) a VSP seismic survey was delayed to a later phase; (2) a new (larger) surface hole would be drilled rather than re-enter an existing well; (3) a 7-in. liner would be placed into the top of the Monterey target as quickly as possible to avoid problems with hole stability; (4) evaluation activities were reduced in scope; (5) geosteering observations for fracture access would be deduced from penetration rate, cuttings description and hydrocarbon in-flow; and (6) rather than use nitrogen, a novel air-injection MPD system was to be implemented. Drilling operations, delayed from the original schedule by capital constraints and lack of rig availability, were conducted from September 12 to November 11, 2004. The vertical and upper curved sections were drilled and lined through the problematic shale member without major stability problems. The top of the targeted Monterey was thought to be seen at the expected TVD of 10,000 ft where the 7-in. liner was set at a 60{sup o} hole angle. Significant oil and gas shows suggested the fractured interval anticipated at the heel location had been penetrated. A total of 2572 ft of 6 1/8-in. near-horizontal interval was placed in the shale section, extending planned well length by approximately 470 ft. Very little hydrocarbon in-flow was observed from fractures along the productive interval. This may be a result of the well trajectory falling underneath the Monterey fractured zone. Hydrocarbon observations, cuttings analysis and gamma-ray response indicated additional fractured intervals were accessed along the last {+-}900 ft of well length. The well was completed with a 2 7/8-in. tubing string set in a production packer in preparation for flow and swab tests to be conducted later by a service rig. The planned well time was estimated as 39 days and overall cost as $2.4 million. The actual results are 66 days at a total cost of $3.4 million. Well productivity responses during subsequent flow and swabbing tests were negative. The well failed to inflow and only minor amounts (a few barrels) of light oil were recovered. The lack of production may suggest that actual sustainable reservoir pressure is far less than anticipated. Temblor is currently planning to re-enter and clean out the well and run an Array Induction log (primarily for resistivity and correlation purposes), and an FMI log (for fracture detection). Depending on the results of these logs, an acidizing or re-drill program will be planned.« less
Physical activity in middle-aged women and hip fracture risk: the UFO study.
Englund, U; Nordström, P; Nilsson, J; Bucht, G; Björnstig, U; Hallmans, G; Svensson, O; Pettersson, U
2011-02-01
In a population-based case-control study, we demonstrate that middle-aged women who were active with walking or in different physical spare time activities were at lower risk of later sustaining a hip fracture compared to more sedentary women. In middle-aged women participating in the Umeå Fracture and Osteoporosis (UFO) study, we investigated whether physical activity is associated with a subsequent decreased risk of sustaining a hip fracture. The UFO study is a nested case-control study investigating associations between bone markers, lifestyle, and osteoporotic fractures. We identified 81 female hip fracture cases that had reported lifestyle data before they sustained their fracture. Each case was compared with two female controls who were identified from the same cohort and matched for age and week of reporting data, yielding a total cohort of 237 subjects. Mean age at baseline was 57.2 ± 5.0 years, and mean age at fracture was 65.4 ± 6.4 years. Conditional logistic regression analysis with adjustments for height, weight, smoking, and menopausal status showed that subjects who were regularly active with walking or had a moderate or high frequency of physical spare time activities (i.e. berry/mushroom picking and snow shovelling) were at reduced risk of sustaining a hip fracture (OR 0.14; 95% CI; 0.05-0.53 for walking and OR 0.19; 95% CI; 0.08-0.46, OR 0.17, 95% CI; 0.05-0.64 for moderate and high frequency of spare time activities, respectively) compared to more sedentary women. An active lifestyle in middle age seems to reduce the risk of future hip fracture. Possible mechanisms may include improved muscle strength, coordination, and balance resulting in a decreased risk of falling and perhaps also direct skeletal benefits.
Gourion-Arsiquaud, Samuel; Lukashova, Lyudmilla; Power, Jon; Loveridge, Nigel; Reeve, Jonathan; Boskey, Adele L
2013-01-01
After the age of 60 years, hip fracture risk strongly increases, but only a fifth of this increase is attributable to reduced bone mineral density (BMD, measured clinically). Changes in bone quality, specifically bone composition as measured by Fourier transform infrared spectroscopic imaging (FTIRI), also contribute to fracture risk. Here, FTIRI was applied to study the femoral neck and provide spatially derived information on its mineral and matrix properties in age-matched fractured and nonfractured bones. Whole femoral neck cross sections, divided into quadrants along the neck's axis, from 10 women with hip fracture and 10 cadaveric controls were studied using FTIRI and micro-computed tomography. Although 3-dimensional micro-CT bone mineral densities were similar, the mineral-to-matrix ratio was reduced in the cases of hip fracture, confirming previous reports. New findings were that the FTIRI microscopic variation (heterogeneity) of the mineral-to-matrix ratio was substantially reduced in the fracture group as was the heterogeneity of the carbonate-to-phosphate ratio. Conversely, the heterogeneity of crystallinity was increased. Increased variation of crystallinity was statistically associated with reduced variation of the carbonate-to-phosphate ratio. Anatomical variation in these properties between the different femoral neck quadrants was reduced in the fracture group compared with controls. Although our treatment-naive patients had reduced rather than increased bending resistance, these changes in heterogeneity associated with hip fracture are in another way comparable to the effects of experimental bisphosphonate therapy, which decreases heterogeneity and other indicators of bone's toughness as a material. Copyright © 2013 American Society for Bone and Mineral Research.
Bits and Pieces: A Crowd-Sourced Series of 54 Cases of Fractured Hormonal Implants.
Crouthamel, Bonnie C; Schiff, Melissa A; Amies Oelschlager, Anne-Marie E; Prager, Sarah W; Debiec, Katherine E
2018-04-01
The fracture of hormonal implants, including Implanon, Nexplanon (both from Merck & Co, Inc), and histrelin acetate is rare. Our aim was to describe patient demographic characteristics, mechanisms, and consequences of fractured implants by surveying physicians' experience via listservs and social media. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: We developed a Research Electronic Data Capture survey for physicians regarding their experience with implant fracture, including patient characteristics, mechanism of fracture, changes in menstrual bleeding patterns, time from insertion to fracture, and time from fracture to seeking care. We distributed the survey to providers in listservs for the North American Society for Pediatric and Adolescent Gynecology, the Family Planning Fellowship, the Ryan Program, and the Facebook Physician Moms Group and Facebook OB-GYN Mom Group. We performed descriptive analyses. We received 42 survey responses, representing 54 discrete implant fractures of which 70% (n=14) were Nexplanon, 26% (n=38) were Implanon, and 4% (n=2) were histrelin acetate. Mechanisms of implant fracture included patient manipulation (23%, n=12), unintentional trauma (11%, n=6), interpersonal violence (8%, n=4), lifting/carrying (6%, n=3), fracture with removal (6%, n=3), and unknown (47%, n=25). Bleeding pattern was not altered in 78% (n=42) of cases. Time interval between placement and fracture was less than 2 years for 63% (n=34) of cases. Thirty-nine percent (n=21) of patients presented for care more than 1 month from the time of fracture. Patients should be counseled about potential for hormonal implant fracture, advised against excessive manipulation of implants, and counseled to present for care immediately upon noticing an implant fracture. Surveying physicians through listervs and social media is an effective strategy to increase the reporting of rare complications and events. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.
Economic analysis of surgical treatment of hip fracture in older adults
Loures, Fabiano Bolpato; Chaoubah, Alfredo; de Oliveira, Valdeci Manoel; Almeida, Alessandra Maciel; Campos, Estela Márcia de Saraiva; de Paiva, Elenir Pereira
2015-01-01
OBJECTIVE To analyze the incremental cost-utility ratio for the surgical treatment of hip fracture in older patients. METHODS This was a retrospective cohort study of a systematic sample of patients who underwent surgery for hip fracture at a central hospital of a macro-region in the state of Minas Gerais, Southeastern Brazil between January 1, 2009 and December 31, 2011. A decision tree creation was analyzed considering the direct medical costs. The study followed the healthcare provider’s perspective and had a one-year time horizon. Effectiveness was measured by the time elapsed between trauma and surgery after dividing the patients into early and late surgery groups. The utility was obtained in a cross-sectional and indirect manner using the EuroQOL 5 Dimensions generic questionnaire transformed into cardinal numbers using the national regulations established by the Center for the Development and Regional Planning of the State of Minas Gerais. The sample included 110 patients, 27 of whom were allocated in the early surgery group and 83 in the late surgery group. The groups were stratified by age, gender, type of fracture, type of surgery, and anesthetic risk. RESULTS The direct medical cost presented a statistically significant increase among patients in the late surgery group (p < 0.005), mainly because of ward costs (p < 0.001). In-hospital mortality was higher in the late surgery group (7.4% versus 16.9%). The decision tree demonstrated the dominance of the early surgery strategy over the late surgery strategy: R$9,854.34 (USD4,387.17) versus R$26,754.56 (USD11,911.03) per quality-adjusted life year. The sensitivity test with extreme values proved the robustness of the results. CONCLUSIONS After controlling for confounding variables, the strategy of early surgery for hip fracture in the older adults was proven to be dominant, because it presented a lower cost and better results than late surgery. PMID:25741654
Machado-Duque, Manuel E; Castaño-Montoya, Juan Pablo; Medina-Morales, Diego A; Castro-Rodríguez, Alejandro; González-Montoya, Alexandra; Machado-Alba, Jorge E
2017-12-10
To determine the association between the use of opioids and benzodiazepines and the risk of falls with hip fracture in populations older than 65 years in Colombia. A case-control study with patients older than 65 years with diagnosis of hip fracture. Two controls were obtained per case. The drugs dispensed in the previous 30 days were identified. Sociodemographic, diagnostic, pharmacological (opioids and benzodiazepines), and polypharmacy variables were analyzed. A logistic regression model was used to analyze the risk of fall with hip fracture while using these drugs. We included 287 patients with hip fractures and 574 controls. There was a female predominance (72.1%) and a mean age of 82.4 ± 8.0 years. Of the patients, 12.7% had been prescribed with opioids and 4.2% with benzodiazepines in the previous month. The adjusted multivariate analysis found that using opioids (OR:4.49; 95%CI:2.72-7.42) and benzodiazepines (OR:3.73; 95%CI:1.60-8.70) in the month prior to the event was significantly associated with a greater probability of suffering a fall with hip fracture. People who are taking opioids and benzodiazepines have increased risk for hip fracture in Colombia. Strategies to educate physicians regarding the pharmacology of older adults should be strengthened.
Hoff, Paula; Gaber, Timo; Strehl, Cindy; Jakstadt, Manuela; Hoff, Holger; Schmidt-Bleek, Katharina; Lang, Annemarie; Röhner, Eric; Huscher, Dörte; Matziolis, Georg; Burmester, Gerd-Rüdiger; Schmidmaier, Gerhard; Perka, Carsten; Duda, Georg N.; Buttgereit, Frank
2017-01-01
Immunologically restricted patients such as those with autoimmune diseases or malignancies often suffer from delayed or insufficient fracture healing. In human fracture hematomas and the surrounding bone marrow obtained from immunologically restricted patients, we analyzed the initial inflammatory phase on cellular and humoral level via flow cytometry and multiplex suspension array. Compared with controls, we demonstrated higher numbers of immune cells like monocytes/macrophages, natural killer T (NKT) cells, and activated T helper cells within the fracture hematomas and/or the surrounding bone marrow. Also, several pro-inflammatory cytokines such as Interleukin (IL)-6 and Tumor necrosis factor α (TNFα), chemokines (e.g., Eotaxin and RANTES), pro-angiogenic factors (e.g., IL-8 and Macrophage migration inhibitory factor: MIF), and regulatory cytokines (e.g., IL-10) were found at higher levels within the fracture hematomas and/or the surrounding bone marrow of immunologically restricted patients when compared to controls. We conclude here that the inflammatory activity on cellular and humoral levels at fracture sites of immunologically restricted patients considerably exceeds that of control patients. The initial inflammatory phase profoundly differs between these patient groups and is probably one of the reasons for prolonged or insufficient fracture healing often occurring within immunologically restricted patients. PMID:28282868
"Nutcracker Fracture" in a Ballet Dancer Performing in The Nutcracker.
Carsen, Sasha; Quinn, Bridget J; Beck, Elizabeth; Southwick, Heather; Micheli, Lyle J
2015-09-01
A 26-year-old female professional dancer sustained an acute injury to her mid-foot during a performance of The Nutcracker. An intra-articular, comminuted, minimally displaced fracture of the cuboid was found. The patient was treated non-operatively with cast and boot immobilization, modified weightbearing, and progressive rehabilitation. She was able to return to professional dance at 6 months post-injury and continues to dance professionally over 1 year out from injury without issue. The unique demands of classical ballet, especially dancing en pointe, increase the risk for mid-foot fractures, and clinicians should have a high-index of suspicion in dancers suffering an acute injury to the foot and ankle with greater than expected pain or swelling. Multiple imaging modalities can be used to make the diagnosis, to include plain film radiographs, MRI, and CT scan. Fracture characteristics and patient-specific factors should be taken into account when deciding on a treatment plan.
Active commuting reduces the risk of wrist fractures in middle-aged women-the UFO study.
Englund, U; Nordström, P; Nilsson, J; Hallmans, G; Svensson, O; Bergström, U; Pettersson-Kymmer, U
2013-02-01
Middle-aged women with active commuting had significantly lower risk for wrist fracture than women commuting by car/bus. Our purpose was to investigate whether a physically active lifestyle in middle-aged women was associated with a reduced risk of later sustaining a low-trauma wrist fracture. The Umeå Fracture and Osteoporosis (UFO) study is a population-based nested case-control study investigating associations between lifestyle and fragility fractures. From a cohort of ~35,000 subjects, we identified 376 female wrist fracture cases who had reported data regarding their commuting habits, occupational, and leisure physical activity, before they sustained their fracture. Each fracture case was compared with at least one control drawn from the same cohort and matched for age and week of reporting data, yielding a total of 778 subjects. Mean age at baseline was 54.3 ± 5.8 years, and mean age at fracture was 60.3 ± 5.8 years. Conditional logistic regression analysis with adjustments for height, body mass index, smoking, and menopausal status showed that subjects with active commuting (especially walking) were at significantly lower risk of sustaining a wrist fracture (OR 0.48; 95 % CI 0.27-0.88) compared with those who commuted by car or bus. Leisure time activities such as dancing and snow shoveling were also associated with a lower fracture risk, whereas occupational activity, training, and leisure walking or cycling were unrelated to fracture risk. This study suggests that active commuting is associated with a lower wrist fracture risk, in middle-aged women.
Lateral X-ray for proximal femoral fractures - Is it really necessary?
Riaz, Osman; Nisar, Sohail; Arshad, Rizwan; Vanker, Raees
2016-10-01
Historically routine work up of a patient with a proximal femoral fracture always included anterior-posterior (AP) and a lateral film of the hip. The aim was to define the role of the lateral X-ray in the assessment and surgical planning of proximal femur fractures. Radiographs of 320 consecutive patients with proximal femoral fractures who were admitted over a 12 months period were divided into lateral and AP views. Two blinded reviewers independently assessed the AP view alone and then the AP plus the lateral view. Fracture classification was noted for each X-ray and then compared with intraoperative diagnosis which was our study's gold standard. A 2 × 2 contingency square table and Pearson's x(2) test were used for statistical analysis. The rate of correct classification by the reviewers enhanced by the assessment of the lateral X-ray in addition to the AP view for intracapsular fractures (p = 0.018) but not for extracapsular fractures (p = 0.29). Operative management did not change for intracapsular fractures which appeared displaced on initial AP view after reviewing the lateral X-ray. The only advantage of obtaining a lateral view in intracapsular fracture was the detection of displacement were the fracture appeared to be undisplaced on initial AP view. This study provides statistical evidence that one view is adequate and safe for majority of proximal femoral fractures. The lateral radiograph should not be performed on a routine basis thus making considerable saving in time and money, and avoiding unnecessary radiation exposure and discomfort to the patient. Copyright © 2015 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.
Hip fracture in hospitalized medical patients
2013-01-01
Background The aim of the present study is to analyze the incidence of hip fracture as a complication of admissions to internal medicine units in Spain. Methods We analyzed the clinical data of 2,134,363 adults who had been admitted to internal medicine wards. The main outcome was a diagnosis of hip fracture during hospitalization. Outcome measures included rates of in-hospital fractures, length of stay and cost. Results A total of 1127 (0.057%) admittances were coded with an in-hospital hip fracture. In hospital mortality rate was 27.9% vs 9.4%; p < 0.001, and the mean length of stay was significantly longer for patients with a hip fracture (20.7 days vs 9.8 days; p < 0.001). Cost were higher in hip-fracture patients (6927€ per hospitalization vs 3730€ in non fracture patients). Risk factors related to fracture were: increasing age by 10 years increments (OR 2.32 95% CI 2.11-2.56), female gender (OR 1.22 95% CI 1.08-1.37), admission from nursing home (OR 1.65 95% CI 1.27-2.12), dementia (1.55 OR 95% CI1.30-1.84), malnutrition (OR 2.50 95% CI 1.88-3.32), delirium (OR 1.57 95% CI 1.16-2.14), and anemia (OR 1.30 95%CI 1.12-1.49). Conclusions In-hospital hip fracture notably increased mortality during hospitalization, doubling the mean length of stay and mean cost of admission. These are reasons enough to stress the importance of designing and applying multidisciplinary plans focused on reducing the incidence of hip fractures in hospitalized patients. PMID:23298165
A likely universal model of fracture scaling and its consequence for crustal hydromechanics
NASA Astrophysics Data System (ADS)
Davy, P.; Le Goc, R.; Darcel, C.; Bour, O.; de Dreuzy, J. R.; Munier, R.
2010-10-01
We argue that most fracture systems are spatially organized according to two main regimes: a "dilute" regime for the smallest fractures, where they can grow independently of each other, and a "dense" regime for which the density distribution is controlled by the mechanical interactions between fractures. We derive a density distribution for the dense regime by acknowledging that, statistically, fractures do not cross a larger one. This very crude rule, which expresses the inhibiting role of large fractures against smaller ones but not the reverse, actually appears be a very strong control on the eventual fracture density distribution since it results in a self-similar distribution whose exponents and density term are fully determined by the fractal dimension D and a dimensionless parameter γ that encompasses the details of fracture correlations and orientations. The range of values for D and γ appears to be extremely limited, which makes this model quite universal. This theory is supported by quantitative data on either fault or joint networks. The transition between the dilute and dense regimes occurs at about a few tenths of a kilometer for faults systems and a few meters for joints. This remarkable difference between both processes is likely due to a large-scale control (localization) of the fracture growth for faulting that does not exist for jointing. Finally, we discuss the consequences of this model on the flow properties and show that these networks are in a critical state, with a large number of nodes carrying a large amount of flow.
NASA Astrophysics Data System (ADS)
Lee, Saro; Dan, Nguyen Tu
2005-09-01
This study evaluates the susceptibility of landslides in the Lai Chau province of Vietnam using Geographic Information System (GIS) and remote sensing data to focus on the relationship between tectonic fractures and landslides. Landslide locations were identified from aerial photographs and field surveys. Topographic, geological data and satellite images were collected, processed, and constructed into a spatial database using GIS data and image-processing techniques. A scheme of the tectonic fracturing of crust in the Lai Chau region was established. Lai Chau was identified as a region with many crustal fractures, where the grade of tectonic fracture is closely related to landslide occurrence. The influencing factors of landslide occurrence were: distance from a tectonic fracture, slope, aspect, curvature, soil, and vegetative land cover. Landslide prone areas were analyzed and mapped using the landslide occurrence factors employing the probability-frequency ratio model. The results of the analysis were verified using landslide location data and showed 83.47% prediction accuracy. That emphasized a strong relationship between the susceptibility map and the existing landslide location data. The results of this study can form a basis stable development and land use planning for the region.
Effects of exercise on fracture reduction in older adults: a systematic review and meta-analysis.
Kemmler, W; Häberle, L; von Stengel, S
2013-07-01
In this meta-analysis, we evaluated the effect of exercise on fracture reduction in the elderly. Our results determined a significantly positive effect on overall fractures, whereas the possibility of a publication bias indicates the need for well-designed (multi-center) trials that generate enough power to focus on osteoporotic fractures. The preventive effect of exercise on fracture incidence has not been clearly determined yet. Thus, the purpose of this study is to evaluate the effectiveness of exercise in preventing overall and vertebral fractures in older adults by meta-analyses technique. This study followed the PRISMA recommendations for systematic reviews and meta-analyses. A systematic review of English articles between 1980 and March 2012 was performed. Terms used were: "exercise", "fractures", "bone", "falls", "osteoporosis", "BMD", "BMC", "bone turnover", while the search was limited to "clinical trial" and "humans". Controlled exercise trials that reported fracture number as endpoint or observation in subjects 45 years and older were included. Ten controlled exercise trials that reported overall fractures and three exercise trials that reported vertebral fractures met our inclusion criteria. Overall fracture number in the exercise group was 36 (n = 754) compared with 73 fractures in the CG (n = 670) (relative risk [RR] = 0.49; 95 % confidence interval [CI], 0.31-0.76). No significant heterogeneity of trial results (p = 0.28; I (2) = 17) was determined; however, there was some evidence to suggest a publication bias. The overall RR for vertebral fracture number (0.56; 95 % CI, 0.30-1.04) (EG: 19 fractures/103 subjects vs. CG: 31 fractures/102 subjects) was borderline non-significant while the heterogeneity of trial results also cannot be ruled out. Although there is evidence that exercise reduces overall and, to a lesser degree, vertebral fractures in the elderly, the possibility of publication bias weakens our result and demonstrates the imperative for large exercise studies with dedicated exercise protocols that focus on fractures as a primary endpoint.
Performance Outcomes After Hook of Hamate Fractures in Major League Baseball Players.
Guss, Michael S; Begly, John P; Ramme, Austin J; Taormina, David P; Rettig, Michael E; Capo, John T
2017-07-17
Major League Baseball (MLB) players are at risk of hook of hamate fractures. There is a paucity of data assessing the effect of a hook of hamate fracture on MLB players' future athletic performance. To determine if MLB players who sustain hook of hamate fractures demonstrate decreased performance upon return to competition when compared with their performance before injury and that of their control-matched peers. Retrospective Case-Control Design. Retrospective Database Study. 18 MLB players who sustained hook of hamate fractures. Data for 18 MLB players with hook of hamate fractures incurred over 26 seasons (1989 to 2014) were obtained from injury reports, press releases, and player profiles ( www.mlb.com and www.baseballreference.com ). Player age, position, number of years in the league, mechanism of injury and treatment were recorded. Individual season statistics for the two seasons immediately prior to injury and the two seasons after injury for the main performance variable - wins above replacement (WAR) were obtained. Eighteen controls matched by player position, age, and performance statistics were identified. A performance comparison of the cohorts was performed. Post-injury performance compared to pre-injury performance and matched-controls. Mean age at the time of injury was 25.1 years with a mean of 4.4 seasons of MLB experience prior to injury. All injuries were sustained to their nondominant batting hand. All players underwent operative intervention. There was no significant change in WAR or ISO when pre-injury and post-injury performance was compared. When compared with matched-controls, no significant decline in performance in WAR the first season and second season after injury was found. MLB players sustaining hook of hamate fractures can reasonably expect to return to their pre-injury performance levels following operative treatment.
Buschbaum, Jan; Fremd, Rainer; Pohlemann, Tim; Kristen, Alexander
2017-08-01
Reduction is a crucial step in the surgical treatment of bone fractures. Finding an optimal path for restoring anatomical alignment is considered technically demanding because collisions as well as high forces caused by surrounding soft tissues can avoid desired reduction movements. The repetition of reduction movements leads to a trial-and-error process which causes a prolonged duration of surgery. By planning an appropriate reduction path-an optimal sequence of target-directed movements-these problems should be overcome. For this purpose, a computer-based method has been developed. Using the example of simple femoral shaft fractures, 3D models are generated out of CT images. A reposition algorithm aligns both fragments by reconstructing their broken edges. According to the criteria of a deduced planning strategy, a modified A*-algorithm searches collision-free route of minimal force from the dislocated into the computed target position. Muscular forces are considered using a musculoskeletal reduction model (OpenSim model), and bone collisions are detected by an appropriate method. Five femoral SYNBONE models were broken into different fracture classification types and were automatically reduced from ten randomly selected displaced positions. Highest mean translational and rotational error for achieving target alignment is [Formula: see text] and [Formula: see text]. Mean value and standard deviation of occurring forces are [Formula: see text] for M. tensor fasciae latae and [Formula: see text] for M. semitendinosus over all trials. These pathways are precise, collision-free, required forces are minimized, and thus regarded as optimal paths. A novel method for planning reduction paths under consideration of collisions and muscular forces is introduced. The results deliver additional knowledge for an appropriate tactical reduction procedure and can provide a basis for further navigated or robotic-assisted developments.
Punjabi, Mansi; Dewan, Ruchika Gupta; Kochhar, Rohit
2017-01-01
Aim and Objectives: The aim of this study is to evaluate and compare the fracture resistance of root canals obturated with four different obturating systems in endodontically treated teeth. Materials and Methods: One hundred and twenty single-rooted teeth were selected and decoronated at cementoenamel junction. Instrumentation of teeth (except control group) was done with Mtwo rotary files up to size 25/0.06 using a step-back technique. All teeth were divided into four experimental groups (n = 25) and two control groups (n = 10). In Group I (negative control), teeth were neither instrumented nor obturated, in Group II (positive control), instrumentation was done, but no obturation was performed, in Group III, obturation was done with cold lateral compaction technique, in Group IV, obturation was done with cold free-flow compaction technique, in Group V, obturation was done with warm vertical compaction technique, and in Group VI, obturation was done with injection-molded thermoplasticized technique. All prepared teeth were embedded in an acrylic resin block, and their fracture strength was measured using Universal Testing Machine. Statistical data were analyzed using one-way analysis of variance and Tukey's honestly significant difference test. Results: Negative control Group I showed highest fracture resistance and positive control Group II had lowest fracture resistance. Among experimental groups, cold free-flow compaction technique with GuttaFlow2 (Group IV) showed higher fracture resistance as compared to the Group III, Group V, and Group VI. Conclusion: GuttaFlow2 has the potential to strengthen the endodontically treated roots to a level that is similar to that of intact teeth. PMID:29430099
Punjabi, Mansi; Dewan, Ruchika Gupta; Kochhar, Rohit
2017-01-01
The aim of this study is to evaluate and compare the fracture resistance of root canals obturated with four different obturating systems in endodontically treated teeth. One hundred and twenty single-rooted teeth were selected and decoronated at cementoenamel junction. Instrumentation of teeth (except control group) was done with Mtwo rotary files up to size 25/0.06 using a step-back technique. All teeth were divided into four experimental groups ( n = 25) and two control groups ( n = 10). In Group I (negative control), teeth were neither instrumented nor obturated, in Group II (positive control), instrumentation was done, but no obturation was performed, in Group III, obturation was done with cold lateral compaction technique, in Group IV, obturation was done with cold free-flow compaction technique, in Group V, obturation was done with warm vertical compaction technique, and in Group VI, obturation was done with injection-molded thermoplasticized technique. All prepared teeth were embedded in an acrylic resin block, and their fracture strength was measured using Universal Testing Machine. Statistical data were analyzed using one-way analysis of variance and Tukey's honestly significant difference test. Negative control Group I showed highest fracture resistance and positive control Group II had lowest fracture resistance. Among experimental groups, cold free-flow compaction technique with GuttaFlow2 (Group IV) showed higher fracture resistance as compared to the Group III, Group V, and Group VI. GuttaFlow2 has the potential to strengthen the endodontically treated roots to a level that is similar to that of intact teeth.
Fracture distribution and porosity in a fault-bound hydrothermal system (Grimsel Pass, Swiss Alps)
NASA Astrophysics Data System (ADS)
Egli, Daniel; Küng, Sulamith; Baumann, Rahel; Berger, Alfons; Baron, Ludovic; Herwegh, Marco
2017-04-01
The spatial distribution, orientation and continuity of brittle and ductile structures strongly control fluid pathways in a rock mass by joining existing pores and creating new pore space (fractures, joints) but can also act as seals to fluid flow (e.g. ductile shear zones, clay-rich fault gouges). In long-lived hydrothermal systems, permeability and the related fluid flow paths are therefore dynamic in space and time. Understanding the evolution and behaviour of naturally porous and permeable rock masses is critical for the successful exploration and sustainable exploitation of hydrothermal systems and can advance methods for planning and implementation of enhanced geothermal systems. This study focuses on an active fault-bound hydrothermal system in the crystalline basement of the Aar Massif (hydrothermal field Grimsel Pass, Swiss Alps) that has been exhumed from few kilometres depth and which documents at least 3 Ma of hydrothermal activity. The explored rock unit of the Aar massif is part of the External Crystalline Massifs that hosts a multitude of thermal springs on its southern border in the Swiss Rhône valley and furthermore represents the exhumed equivalent of potentially exploitable geothermal reservoirs in the deep crystalline subsurface of the northern Alpine foreland basin. This study combines structural data collected from a 125 m long drillhole across the hydrothermal zone, the corresponding drill core and surface mapping. Different methods are applied to estimate the porosity and the structural evolution with regard to porosity, permeability and fracture distribution. Analyses are carried out from the micrometre to decametre scale with main focus on the flow path evolution with time. This includes a large variety of porosity-types including fracture-porosity with up to cm-sized aperture down to grain-scale porosity. Main rock types are granitoid host rocks, mylonites, paleo-breccia and recent breccias. The porosity of the host rock as well as the cemented paleo-hydrothermal breccia is typically very low with values <1%. The high volume of mineralized fractures in the paleo-breccia indicates high porosity in former times, which is today closed by newly developed cements. The preservation of such paleo-breccias allow the investigation of contrasts between the fossil porosity/permeability and the present day active flow path, which is defined by fracture porosity that generally follows the regional deformation pattern and forms a wide network of interconnected fractures of variable orientation.
Perroud, H A; Dagatti, M S; Amigot, B; Levit, G P; Tomat, M F; Morosano, M E; Masoni, A M; Pezzotto, S M
2017-05-01
The aim of this study was to analyze the association between the presence of actinic lesions (solar keratosis and non-melanoma skin cancer) and osteoporotic hip fractures in older patients. Both pathologies are common conditions in this age group. Since cumulative sun exposure is difficult to quantify, the presence of actinic lesions can be used to indirectly analyze the association between ultraviolet radiation and osteoporotic hip fractures. This was an observational case-control study. We reviewed the centralized medical records of patients with hip fracture (cases, n = 51) and patients with other diseases hospitalized in the same institution and period (controls, n = 59). The mean age of the patients was 80 ± 8.3 years (range 50-103 years). Differences in maternal hip fracture history were found between cases and controls (14.8 and 8 %, respectively; p = 0.047). Falls history in the past year was higher in cases than in controls (p < 0.0001). Actinic lesions were observed in 32.7 % of patients (prevalence rate 23.5 % in cases, 40.7 % in controls; p = 0.04). When considering patients with actinic lesions, controls have a higher FRAX score compared with cases. Although sun exposure is recommended for bone health, it represents a risk factor for actinic lesions. The presence of actinic lesions may indicate a lower osteoporotic hip fracture risk. A balance between adequate lifetime sun exposure and protection against its adverse effects is required for each patient, in the context of geographic location.
Losada, E; Soldevila, B; Ali, M S; Martínez-Laguna, D; Nogués, X; Puig-Domingo, M; Díez-Pérez, A; Mauricio, D; Prieto-Alhambra, D
2018-06-02
We conducted a nested case-control study to study the association between antidiabetic treatments (alone or in combination) use and fracture risk among incident type 2 Diabetes mellitus patients. We found an increased risk of bone fracture with insulin therapy compared to metformin monotherapy. Patients with type 2 diabetes mellitus (T2DM) have an increased risk of fragility fractures, to which antidiabetic therapies may contribute. We aimed to characterize the risk of fracture associated with different antidiabetic treatments as usually prescribed to T2DM patients in actual practice conditions. A case-control study was nested within a cohort of incident T2DM patients registered in 2006-2012 in the Information System for Research Development in Primary Care (Catalan acronym, SIDIAP), a database which includes records for > 5.5 million patients in Catalonia (Spain). Each case (incident major osteoporotic fracture) was risk-set matched with up to five same-sex controls by calendar year of T2DM diagnosis and year of birth (± 10 years). Study exposure included previous use of all antidiabetic medications (alone or in combination), as dispensed in the 6 months before the index date, with metformin (MTF) monotherapy, the most commonly used drug, as a reference group (active comparator). Data on 12,277 T2DM patients (2049 cases and 10,228 controls) were analyzed. Insulin use was associated with increased fracture risk (adjusted OR 1.63 (95% CI 1.30-2.04)), as was the combination of MTF and sulfonylurea (SU) (adjusted OR 1.29 (1.07-1.56)), compared with MTF monotherapy. Sensitivity analyses suggest possible causality for insulin therapy but not for the MTF + SU combination association. No significant association was found with any other antidiabetic medications. Insulin monotherapy was associated with an increased fracture risk compared to MTF monotherapy in T2DM patients. Fracture risk should be taken into account when starting a glucose-lowering drug as part of T2DM treatment.
Cotté, François-Emery; Mercier, Florence; De Pouvourville, Gérard
2008-12-01
Nonadherence to treatment is an important determinant of long-term outcomes in women with osteoporosis. This study was conducted to investigate the association between adherence and osteoporotic fracture risk and to identify optimal thresholds for good compliance and persistence. A secondary objective was to perform a preliminary evaluation of the cost consequences of adherence. This was a retrospective case-control analysis. Data were derived from the Thales prescription database, which contains information on >1.6 million patients in the primary health care setting in France. Cases were women aged >or=50 years who had an osteoporosis-related fracture in 2006. For each case, 5 matched controls were randomly selected. Both compliance and persistence aspects of treatment adherence were examined. Compliance was estimated based on the medication possession ratio (MPR). Persistence was calculated as the time from the initial filling of a prescription for osteoporosis medication until its discontinuation. The mean (SD) MPR was lower in cases compared with controls (58.8% [34.7%] vs 72.1% [28.8%], respectively; P < 0.001). Cases were more likely than controls to discontinue osteoporosis treatment (50.0% vs 25.3%; P < 0.001), yielding a significantly lower proportion of patients who were still persistent at 1 year (34.1% vs 40.9%; P < 0.001). MPR was the best predictor of fracture risk, with an area under the receiver-operating-characteristic curve that was higher than that for persistence (0.59 vs 0.55). The optimal MPR threshold for predicting fracture risk was >or=68.0%. Compared with less-compliant women, women who achieved this threshold had a 51% reduction in fracture risk. The difference in annual drug expenditure between women achieving this threshold and those who did not was approximately euro300. The optimal threshold for persistence with therapy was at least 6 months. Attaining this threshold was associated with a 28% reduction in fracture risk compared with less-persistent women. In this study, better treatment adherence was associated with a greater reduction in fracture risk. Compliance appeared to predict fracture risk better than did persistence.
Wang, Chao
We conducted a meta-analysis based on eligible studies to assess the efficacy and safety of zoledronic acid treatment for postmenopausal women with osteoporosis. PubMed, Web of Science, and Embase were searched for eligible studies that assessed the efficacy of zoledronic acid in the prevention of fractures among postmenopausal women with osteoporosis. The primary outcomes were new vertebral fracture, nonvertebral fracture, and hip fracture. Secondary outcomes were bone mineral density (BMD) and safety outcomes. A fixed-effect or random-effect model was used to pool the estimates according to the heterogeneity among the included studies. Eight randomized controlled trials, involving 13,335 patients, were included in this meta-analysis. Pooled results showed that treatment with zoledronic acid significantly reduced the incidences of nonvertebral fractures, vertebral fractures, and hip fractures, as compared with placebo. Zoledronic acid was also associated with significant improvement in BMD at lumbar spine, total hip, femoral neck, and trochanter. However, the incidence of any adverse events was higher in the zoledronic acid group than that in the control group, and serious adverse events were comparable between the 2 groups. This meta-analysis indicated that zoledronic acid could significantly reduce the fracture risk and increase BMD in postmenopausal women with osteoporosis. Furthermore, it would not result in serious adverse events. Zoledronic acid could be used as an effective and well-tolerated treatment for postmenopausal women with osteoporosis.
Epidemic of fractures during a period of snow and ice: has anything changed 33 years on?
Al-Azzani, Waheeb; Adam Maliq Mak, Danial; Hodgson, Paul; Williams, Rhodri
2016-01-01
Objectives We reproduced a frequently cited study that was published in the British Medical Journal (BMJ) in 1981 assessing the extent of ‘snow-and-ice’ fractures during the winter period. Setting This study aims to provide an insight into how things have changed within the same emergency department (ED) by comparing the findings of the BMJ paper published 33 years ago with the present date. Participants As per the original study, all patients presenting to the ED with a radiological evidence of fracture during three different 4-day periods were included. The three 4-day periods included 4 days of snow-and-ice conditions and two control 4-day periods when snow and ice was not present; the first was 4 days within the same year, with a similar amount of sunshine hours, and the second was 4 days 1 calendar year later. Primary and secondary outcome measures To identify the frequency, distribution and pattern of fractures sustained in snow-and-ice conditions compared to control conditions as well as comparisons with the index study 33 years ago. Results A total of 293 patients with fractures were identified. Overall, there was a 2.20 (CI 1.7 to 3.0, p <0.01) increase in risk of fracture during snow-and-ice periods compared to control conditions. There was an increase (p <0.01) of fractures of the arm, forearm and wrist (RR 3.2 (CI 1.4 to 7.6) and 2.9 (CI 1.5 to 5.4) respectively). Conclusions While the relative risk was not of the magnitude 33 years ago, the overall number of patients presenting with a fracture during snow-and-ice conditions remains more than double compared to control conditions. This highlights the need for improved understanding of the impact of increased fracture burden on hospitals and more effective preventative measures. PMID:27630066
NASA Astrophysics Data System (ADS)
Ladevèze, P.; Séjourné, S.; Rivard, C.; Lavoie, D.; Lefebvre, R.; Rouleau, A.
2018-03-01
In the St. Lawrence sedimentary platform (eastern Canada), very little data are available between shallow fresh water aquifers and deep geological hydrocarbon reservoir units (here referred to as the intermediate zone). Characterization of this intermediate zone is crucial, as the latter controls aquifer vulnerability to operations carried out at depth. In this paper, the natural fracture networks in shallow aquifers and in the Utica shale gas reservoir are documented in an attempt to indirectly characterize the intermediate zone. This study used structural data from outcrops, shallow observation well logs and deep shale gas well logs to propose a conceptual model of the natural fracture network. Shallow and deep fractures were categorized into three sets of steeply-dipping fractures and into a set of bedding-parallel fractures. Some lithological and structural controls on fracture distribution were identified. The regional geologic history and similarities between the shallow and deep fracture datasets allowed the extrapolation of the fracture network characterization to the intermediate zone. This study thus highlights the benefits of using both datasets simultaneously, while they are generally interpreted separately. Recommendations are also proposed for future environmental assessment studies in which the existence of preferential flow pathways and potential upward fluid migration toward shallow aquifers need to be identified.
Influence of mechanical rock properties and fracture healing rate on crustal fluid flow dynamics
NASA Astrophysics Data System (ADS)
Sachau, Till; Bons, Paul; Gomez-Rivas, Enrique; Koehn, Daniel; de Riese, Tamara
2016-04-01
Fluid flow in the Earth's crust is very slow over extended periods of time, during which it occurs within the connected pore space of rocks. If the fluid production rate exceeds a certain threshold, matrix permeability alone is insufficient to drain the fluid volume and fluid pressure builds up, thereby reducing the effective stress supported by the rock matrix. Hydraulic fractures form once the effective pressure exceeds the tensile strength of the rock matrix and act subsequently as highly effective fluid conduits. Once local fluid pressure is sufficiently low again, flow ceases and fractures begin to heal. Since fluid flow is controlled by the alternation of fracture permeability and matrix permeability, the flow rate in the system is strongly discontinuous and occurs in intermittent pulses. Resulting hydraulic fracture networks are largely self-organized: opening and subsequent healing of hydraulic fractures depends on the local fluid pressure and on the time-span between fluid pulses. We simulate this process with a computer model and describe the resulting dynamics statistically. Special interest is given to a) the spatially and temporally discontinuous formation and closure of fractures and fracture networks and b) the total flow rate over time. The computer model consists of a crustal-scale dual-porosity setup. Control parameters are the pressure- and time-dependent fracture healing rate, and the strength and the permeability of the intact rock. Statistical analysis involves determination of the multifractal properties and of the power spectral density of the temporal development of the total drainage rate and hydraulic fractures. References Bons, P. D. (2001). The formation of large quartz veins by rapid ascent of fluids in mobile hydrofractures. Tectonophysics, 336, 1-17. Miller, S. a., & Nur, A. (2000). Permeability as a toggle switch in fluid-controlled crustal processes. Earth and Planetary Science Letters, 183(1-2), 133-146. Sachau, T., Bons, P. D., & Gomez-Rivas, E. (2015). Transport efficiency and dynamics of hydraulic fracture networks. Frontiers in Physics, 3.
Barker, Anna L; McNeil, John J; Seeman, Ego; Ward, Stephanie A; Sanders, Kerrie M; Khosla, Sundeep; Cumming, Robert G; Pasco, Julie A; Bohensky, Megan A; Ebeling, Peter R; Woods, Robyn L; Lockery, Jessica E; Wolfe, Rory; Talevski, Jason
2016-08-01
Disability, mortality and healthcare burden from fractures in older people is a growing problem worldwide. Observational studies suggest that aspirin may reduce fracture risk. While these studies provide room for optimism, randomised controlled trials are needed. This paper describes the rationale and design of the ASPirin in Reducing Events in the Elderly (ASPREE)-Fracture substudy, which aims to determine whether daily low-dose aspirin decreases fracture risk in healthy older people. ASPREE is a double-blind, randomised, placebo-controlled primary prevention trial designed to assess whether daily active treatment using low-dose aspirin extends the duration of disability-free and dementia-free life in 19 000 healthy older people recruited from Australian and US community settings. This substudy extends the ASPREE trial data collection to determine the effect of daily low-dose aspirin on fracture and fall-related hospital presentation risk in the 16 500 ASPREE participants aged ≥70 years recruited in Australia. The intervention is a once daily dose of enteric-coated aspirin (100 mg) versus a matching placebo, randomised on a 1:1 basis. The primary outcome for this substudy is the occurrence of any fracture-vertebral, hip and non-vert-non-hip-occurring post randomisation. Fall-related hospital presentations are a secondary outcome. This substudy will determine whether a widely available, simple and inexpensive health intervention-aspirin-reduces the risk of fractures in older Australians. If it is demonstrated to safely reduce the risk of fractures and serious falls, it is possible that aspirin might provide a means of fracture prevention. The protocol for this substudy is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12615000347561). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
2012-01-01
Background Knowledge on the epidemiology of non-hip fractures in Spain is limited and somewhat outdated. Using computerized primary care records from the SIDIAP database, we derived age and sex-specific fracture incidence rates for the region of Catalonia during the year 2009. Methods The SIDIAP database contains quality-checked clinical information from computerized medical records of a representative sample of >5,800,000 patients (80% of the population of Catalonia). We conducted a retrospective cohort study including all patients aged ≥50 years, and followed them from January 1 to December 31, 2009. Major osteoporotic fractures registered in SIDIAP were ascertained using ICD-10 codes and validated by comparing data to hospital admission and patient-reported fractures records. Incidence rates and 95% confidence intervals were calculated. Results In total, 2,011,430 subjects were studied (54.6% women). Overall fracture rates were 10.91/1,000 person-years (py) [95%CI 10.89–10.92]: 15.18/1,000 py [15.15–15.21] in women and 5.78/1,000 py [5.76–5.79] in men. The most common fracture among women was wrist/forearm (3.86/1,000 py [3.74–3.98]), while among men it was clinical spine (1.25/1,000 py [1.18–1.33]). All fracture rates increased with age, but varying patterns were observed: while most of the fractures (hip, proximal humerus, clinical spine and pelvis) increased continuously with age, wrist and multiple rib fractures peaked at age 75–80 and then reached a plateau. Conclusions Our study provides local estimates of age, sex and site-specific fracture burden in primary health care, which will be helpful for health-care planning and delivery. A proportion of fractures are not reported in primary care records, leading to underestimation of fracture incidence rates in these data. PMID:22639802
[Trochanteric femoral fractures: anatomy, biomechanics and choice of implants].
Bonnaire, F; Lein, T; Bula, P
2011-06-01
The objective of any surgical care of a trochanteric femoral fracture should be the achievement of a stable osteosynthesis that allows early full weight-bearing mobilisation of the patient, because long-term immobilisation soon becomes a vital threat to the affected patients who are usually elderly with correlating comorbidities. The anatomical references of the proximal femur and the structure of the hip joint contain some specifics that play an essential role in the incurrence of a trochanteric femoral fracture and the planning of the osteosynthesis as well. With reposition and fracture stabilisation particular importance must be attached to the collo-diaphyseal and the antetorsion angle so that they do not interfere with the functional interaction of the hip and knee joint. Uncomplex trochanteric fractures ordinarily stabilise sufficiently after reposition so that even an extramedullary implant can ensure full weight-bearing stability. With evermore distal fracture course and intertrochanteric comminution zone, rotational instability and pivot transfer of the fracture area to lateral and caudal are followed by an increase of the dislocating forces. These kinds of fractures (A2 and A3 according to the AO/ASIF classification) profit from an intramedullary and rotationally stable osteosynthesis. Basically primary total hip arthroplasty is a potential option for surgical care of a trochanteric fracture in elderly patients with relevant coxarthrosis. However this procedure can only be recommended in cases of a stable uncomplex fracture. The more the medial interlocking of the proximal femur is destroyed the more difficult it will be to primarily implant a total hip prosthesis with good offset and without a varus and rotational failure in the fracture zone.The current studies in the main show disadvantages due to increased complications in these patients, so that in cases of an unstable trochanteric fracture a primary osteosynthesis should be performed followed by total hip arthroplasty after fracture consolidation has occurred.
Identification of fracture zones and its application in automatic bone fracture reduction.
Paulano-Godino, Félix; Jiménez-Delgado, Juan J
2017-04-01
The preoperative planning of bone fractures using information from CT scans increases the probability of obtaining satisfactory results, since specialists are provided with additional information before surgery. The reduction of complex bone fractures requires solving a 3D puzzle in order to place each fragment into its correct position. Computer-assisted solutions may aid in this process by identifying the number of fragments and their location, by calculating the fracture zones or even by computing the correct position of each fragment. The main goal of this paper is the development of an automatic method to calculate contact zones between fragments and thus to ease the computation of bone fracture reduction. In this paper, an automatic method to calculate the contact zone between two bone fragments is presented. In a previous step, bone fragments are segmented and labelled from CT images and a point cloud is generated for each bone fragment. The calculated contact zones enable the automatic reduction of complex fractures. To that end, an automatic method to match bone fragments in complex fractures is also presented. The proposed method has been successfully applied in the calculation of the contact zone of 4 different bones from the ankle area. The calculated fracture zones enabled the reduction of all the tested cases using the presented matching algorithm. The performed tests show that the reduction of these fractures using the proposed methods leaded to a small overlapping between fragments. The presented method makes the application of puzzle-solving strategies easier, since it does not obtain the entire fracture zone but the contact area between each pair of fragments. Therefore, it is not necessary to find correspondences between fracture zones and fragments may be aligned two by two. The developed algorithms have been successfully applied in different fracture cases in the ankle area. The small overlapping error obtained in the performed tests demonstrates the absence of visual overlapping in the figures. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Navigation system for robot-assisted intra-articular lower-limb fracture surgery.
Dagnino, Giulio; Georgilas, Ioannis; Köhler, Paul; Morad, Samir; Atkins, Roger; Dogramadzi, Sanja
2016-10-01
In the surgical treatment for lower-leg intra-articular fractures, the fragments have to be positioned and aligned to reconstruct the fractured bone as precisely as possible, to allow the joint to function correctly again. Standard procedures use 2D radiographs to estimate the desired reduction position of bone fragments. However, optimal correction in a 3D space requires 3D imaging. This paper introduces a new navigation system that uses pre-operative planning based on 3D CT data and intra-operative 3D guidance to virtually reduce lower-limb intra-articular fractures. Physical reduction in the fractures is then performed by our robotic system based on the virtual reduction. 3D models of bone fragments are segmented from CT scan. Fragments are pre-operatively visualized on the screen and virtually manipulated by the surgeon through a dedicated GUI to achieve the virtual reduction in the fracture. Intra-operatively, the actual position of the bone fragments is provided by an optical tracker enabling real-time 3D guidance. The motion commands for the robot connected to the bone fragment are generated, and the fracture physically reduced based on the surgeon's virtual reduction. To test the system, four femur models were fractured to obtain four different distal femur fracture types. Each one of them was subsequently reduced 20 times by a surgeon using our system. The navigation system allowed an orthopaedic surgeon to virtually reduce the fracture with a maximum residual positioning error of [Formula: see text] (translational) and [Formula: see text] (rotational). Correspondent physical reductions resulted in an accuracy of 1.03 ± 0.2 mm and [Formula: see text], when the robot reduced the fracture. Experimental outcome demonstrates the accuracy and effectiveness of the proposed navigation system, presenting a fracture reduction accuracy of about 1 mm and [Formula: see text], and meeting the clinical requirements for distal femur fracture reduction procedures.
Wang, Tien-Hsiang; Ma, Hsu; Tseng, Ching-Shiow; Chou, Yi-Hong; Cai, Kun-Lin
Surgical navigation systems have been an important tool in maxillofacial surgery, helping surgeons create a presurgical plan, locate lesions, and provide guidance. For secondary facial bone reductions, a good presurgical plan and proper execution are the key to success. Previous studies used predetermined markers and screw holes as navigation references; however, unexpected situations may occur, making the predetermined surgical plan unreliable. Instead of determining positions preoperatively, this study proposes a method that surgeons can use intraoperatively to choose surface markers in a more flexible manner. Eight zygomatic fractures were created in four skull models, and preoperative computed tomography (CT) image data were imported into a self-developed navigation program for presurgical planning. This program also calculates the ideal positions of navigation references points for screw holes. During reduction surgery, markers on fractured bone are selected, registered, and calculated as free navigation reference points (FNRPs). The surface markers and FNRPs are used to monitor the position of the dislocated bone. Titanium bone plates were prefabricated on stereolithography models for osteosynthesis. Two reductions with only FNRPs, as well as six reductions with FNRPs and prefabricated bone plates, were successfully performed. Postoperative CT data were obtained, and surgical errors in the six-reduction group were evaluated. The average deviation from the screw hole drilling positions was 0.92 ± 0.38 mm. The average deviation included displacement and rotation of the zygomas. The mean displacement was 0.83 ± 0.38 mm, and the average rotations around the x, y, and z axes were 0.66 ± 0.59°, 0.77 ± 0.54°, and 0.79 ± 0.42°, respectively. The results show that combining presurgical planning and the developed navigation program to generate FNRPs for assisting in secondary zygoma reduction is an accurate and practical method. Further study is necessary to prove its clinical value.
USDA-ARS?s Scientific Manuscript database
Guidelines for post-fracture care of elderly hip fracture patients are not established despite the significant socio-economic burden of post hip fracture morbidity and mortality. Using a factorial design, we studied the effects of extended physiotherapy (supervised 1 hour per day during acute care p...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fernandez, Carlos A.; Heldebrant, David J.; Bonneville, Alain
An electrophilic acid gas-reactive fracturing fluid, proppant, and process are detailed. The fluid expands in volume to provide rapid and controlled increases in pressure that enhances fracturing in subterranean bedrock for recovery of energy-producing materials. The proppant stabilizes fracture openings in the bedrock to enhance recovery of energy-producing materials.
A biomechanical comparison of four different fixation methods for midshaft clavicle fractures.
Chen, Yang; Yang, Yang; Ma, Xinlong; Xu, Weiguo; Ma, Jianxiong; Zhu, Shaowen; Ma, Baoyi; Xing, Dan
2016-01-01
Clavicle fractures may occur in all age groups, and 70%-80% of clavicle fractures occur in the midshaft. Many methods for treating midshaft clavicular fractures have been reported and remain controversial. To provide some guidance for clinical treatment, 30 artificial polymethyl methacrylate models of the clavicle were sewn obliquely at the midshaft to simulate the most common type of clavicular fractures, and the fracture models were divided into five groups randomly and were fixed as follows: the reconstruction plates were placed at the superior position of the fracture model (R-S group), the reconstruction plates were placed at the anteroinferior position of the fracture model (R-AI group), the locking plates were placed at the superior position (L-S group), the locking plates were placed at the anteroinferior position (L-AI group); and the control models were unfixed (control group). The strain gauges were attached to the bone surface near the fracture fragments, and then, the biomechanical properties of the specimens were measured using the compression test, torsion test and three-point bending test. The results showed that plate fixation can provide a stable construct to help with fracture healing and is the preferred method in the treatment of clavicle fractures. The locking plate provides the best biomechanical stability when placed at the anteroinferior position, and this surgical method can reduce the operation time and postoperative complications; thus, it would be a better choice in clinical practice. © IMechE 2015.
NASA Astrophysics Data System (ADS)
Brook, Martin; Hebblewhite, Bruce; Mitra, Rudrajit
2016-04-01
The size-scaling of rock fractures is a well-studied problem in geology, especially for permeability quantification. The intensity of fractures may control the economic exploitation of fractured reservoirs because fracture intensity describes the abundance of fractures potentially available for fluid flow. Moreover, in geotechnical engineering, fractures are important for parameterisation of stress models and excavation design. As fracture data is often collected from widely-spaced boreholes where core recovery is often incomplete, accurate interpretation and representation of fracture aperture-frequency relationships from sparse datasets is important. Fracture intensity is the number of fractures encountered per unit length along a sample scanline oriented perpendicular to the fractures in a set. Cumulative frequency of fractures (F) is commonly related to fracture aperture (A) in the form of a power-law (F = aA-b), with variations in the size of the a coefficient between sites interpreted to equate to fracture frequency for a given aperture (A). However, a common flaw in this approach is that even a small change in b can have a large effect on the response of the fracture frequency (F) parameter. We compare fracture data from the Late Permian Rangal Coal Measures from Australia's Bowen Basin, with fracture data from Jurassic carbonates from the Sierra Madre Oriental, northeastern Mexico. Both power-law coefficient a and exponent b control the fracture aperture-frequency relationship in conjunction with each other; that is, power-laws with relatively low a coefficients have relatively high b exponents and vice versa. Hence, any comparison of different power-laws must take both a and b into consideration. The corollary is that different sedimentary beds in the Sierra Madre carbonates do not show ˜8× the fracture frequency for a given fracture aperture, as based solely on the comparison of coefficient a. Rather, power-law "sensitivity factors" developed from both Sierra Madre and the Bowen Basin span similar ranges, indicating that the factor of increase in frequency (F) for a doubling of aperture size (A) shows similar relationships and variability from both sites. Despite their limitations, we conclude that fracture aperture-frequency power-law relationships are valid and, when interpreted carefully, provide a useful basis for comparing rock fracture distributions across different sites.
Raaben, Marco; Redzwan, Syaiful; Augustine, Robin; Blokhuis, Taco Johan
2018-04-12
Proximal femur fractures are a common injury after low energy trauma in the elderly. Most rehabilitation programs are based on restoring mobility and early resumption of weight-bearing. However, therapy compliance is low in patients following lower extremity fractures. Moreover, little is known about the relevance of gait parameters and how to steer the rehabilitation after proximal femur fractures in the elderly. Therefore, the aim of this prospective, randomized controlled trial is to gain insight in gait parameters and evaluate if real-time visual biofeedback can improve therapy compliance after proximal femur fractures in the elderly. This is a two-arm, parallel-design, prospective, randomized controlled trial. Inclusion criteria are age ≥ 60 years, a proximal femur fracture following low energy trauma, and unrestricted-weight bearing. Exclusion criteria are cognitive impairment and limited mobility before trauma. Participants are randomized into either the control group, which receives care as usual, or the intervention group, which receives real-time visual biofeedback about weight-bearing during gait in addition to care as usual. Spatiotemporal gait parameters will be measured in 94 participants per group during a 30-m walk with an ambulatory biofeedback system (SensiStep). The progress of rehabilitation will be evaluated by the primary outcome parameters maximum peak load and step duration in relation to the discharge date. Secondary outcome parameters include other spatiotemporal gait parameters in relation to discharge date. Furthermore, the gait parameters will be related to three validated clinical tests: Elderly Mobility Scale; Functional Ambulation Categories; and Visual Analogue Scale. The primary hypothesis is that participants in the intervention group will show improved and faster rehabilitation compared to the control group. The first aim of this multicenter trial is to investigate the normal gait patterns after proximal femur fractures in the elderly. The use of biofeedback systems during rehabilitation after proximal femur fractures in the elderly is promising; therefore, the second aim is to investigate the effect of real-time visual biofeedback on gait after proximal femur fractures in the elderly. This could lead to improved outcome. In addition, analysis of the population may indicate characteristics of subgroups that benefit from feedback, making a differentiated approach in rehabilitation strategy possible. TrialRegister.nl, NTR6794 . Registered on 31 October 2017.
Pearson, Krystal
2012-01-01
The Upper Cretaceous Austin Chalk forms a low-permeability, onshore Gulf of Mexico reservoir that produces oil and gas from major fractures oriented parallel to the underlying Lower Cretaceous shelf edge. Horizontal drilling links these fracture systems to create an interconnected network that drains the reservoir. Field and well locations along the production trend are controlled by fracture networks. Highly fractured chalk is present along both regional and local fault zones. Fractures are also genetically linked to movement of the underlying Jurassic Louann Salt with tensile fractures forming downdip of salt-related structures creating the most effective reservoirs. Undiscovered accumulations should also be associated with structure-controlled fracture systems because much of the Austin that overlies the Lower Cretaceous shelf edge remains unexplored. The Upper Cretaceous Eagle Ford Shale is the primary source rock for Austin Chalk hydrocarbons. This transgressive marine shale varies in thickness and lithology across the study area and contains both oil- and gas-prone kerogen. The Eagle Ford began generating oil and gas in the early Miocene, and vertical migration through fractures was sufficient to charge the Austin reservoirs.
Self-Organizing Fluid Convection Patterns in an en Echelon Fault Array
NASA Astrophysics Data System (ADS)
Patterson, James W.; Driesner, Thomas; Matthai, Stephan K.
2018-05-01
We present three-dimensional numerical simulations of natural convection in buried, vertical en echelon faults in impermeable host rock. Despite the fractures being hydraulically disconnected, convection within each fracture alters the temperature field in the surrounding host rock, altering convection in neighboring fractures. This leads to self-organization of coherent patterns of upward/downward flow and heating/cooling of the host rock spanning the entire fault array. This "synchronization" effect occurs when fracture spacing is less than the width of convection cells within the fractures, which is controlled by fracture transmissivity (permeability times thickness) and heterogeneity. Narrow fracture spacing and synchronization enhance convective fluid flow within fractures and cause convection to initiate earlier, even lowering the critical transmissivity necessary for convection initiation. Heat flow through the en echelon region, however, is enhanced only in low-transmissivity fractures, while heat flow in high-permeability fractures is reduced due to thermal interference between fractures.
Fractography of induction-hardened steel fractured in fatigue and overload
DOE Office of Scientific and Technical Information (OSTI.GOV)
Santos, C.G.; Laird, C.
1997-07-01
The fracture surfaces of induction-hardened steel specimens obtained from an auto axle were characterized, macroscopically and microscopically, after being fractured in fatigue and monotonic overload. Specimens were tested in cyclic three-point bending under load control, and the S-N curve was established for specimens that had been notched by spark machining to facilitate fractography. Scanning electron microscopy of the fractured surfaces obtained for lives spanning the range 17,000 to 418,000 cycles revealed diverse fracture morphologies, including intergranular fracture and transgranular fatigue fracture. The results are being offered to assist in the analysis of complex field failures in strongly hardened steel.
Kay, Alastair T; Durgam, Sushmitha; Stewart, Matthew; Joslyn, Stephen; Schaeffer, David J; Horn, Gavin; Kesler, Richard; Chew, Peter
2016-11-01
To compare reduction of type III distal phalangeal fractures using 4.5 and 5.5 mm cortical screws placed in lag fashion and an intact hoof capsule model. Cadaveric experimental study. Hooves from 12 adult horses (n=24). Sagittal fractures were created in pairs of distal phalanges after distal interphalangeal joint disarticulation and were reduced with either 4.5 or 5.5 mm cortical screws placed in lag fashion. Contralateral phalanges served as non-reduced controls. Fracture reduction following screw placement was assessed by comparing pre-reduction and post-reduction fracture gap measurements from radiographs using paired t-tests. Effects of incremental loading (0, 135, 270, 540, 800, 1070, and 1335 kg) on fracture gaps in 6 phalanges reduced with 4.5 mm screws and 5 phalanges reduced with 5.5 mm screws were measured from fluoroscopic images and assessed by 2-way ANOVA. Significance was set at P<.05. Type III distal phalanx fractures were reliably created. Only 5.5 mm cortical screws, not 4.5 mm screws, significantly reduced fracture gaps and constrained fracture gap expansion 3 cm distal to the articular surface. Compressive loading closed the fracture gaps at the articular surface in both non-reduced control groups and those reduced with either 5.5 or 4.5 mm screws. The 5.5 mm cortical screws were more effective than 4.5 mm screws in reducing type III distal phalanx fractures and restricting distal fracture gap expansion under load. © Copyright 2016 by The American College of Veterinary Surgeons.
Niobrara Discrete Fracture Network: From Outcrop Surveys to Subsurface Reservoir Models
NASA Astrophysics Data System (ADS)
Grechishnikova, Alena
Heterogeneity of an unconventional reservoir is one of the main factors affecting production. Well performance depends on the size and efficiency of the interconnected fracture "plumbing system", as influenced by multistage hydraulic fracturing. A complex, interconnected natural fracture network can significantly increase the size of stimulated reservoir volume, provide additional surface area contact and enhance permeability. In 2013 the Reservoir Characterization Project (RCP) at the Colorado School of Mines began Phase XV to study Niobrara shale reservoir management. Anadarko Petroleum Corporation and RCP jointly acquired time-lapse multicomponent seismic data in Wattenberg Field, Denver Basin. Anadarko also provided RCP with a regional 3D seismic survey and a rich well dataset. The purpose of this study is to characterize the natural fracture patterns occurring in the unconventional Niobrara reservoir and to determine the drivers that influenced fracture trends and distributions. The findings are integrated into a reservoir model though DFN (Discrete Fracture Network) for further prediction of reservoir performance using reservoir simulations. Aiming to better understand the complexity of the natural fracture system I began my fracture analysis work at an active mine site that provides a Niobrara exposure. Access to a "fresh" outcrop surface created a perfect natural laboratory. Ground-based LIDAR and photogrammetry facilitated construction of a geological model and a DFN model for the mine site. The work was carried into subsurface where the information gained served to improve reservoir characterization at a sub-seismic scale and can be used in well planning. I then embarked on a challenging yet essential task of outcrop-to-subsurface data calibration and application to RCP's Wattenberg Field study site. In this research the surface data was proven to be valid for comparative use in the subsurface. The subsurface fracture information was derived from image logs run within the horizontal wellbores and augmented with microseismic data. Limitations of these datasets included the potential to induce biased interpretations; but the data collected during the outcrop study aided in removing the bias. All four fracture sets observed at the quarry were also interpreted in the subsurface; however there was a limitation on statistical validity for one of the four sets due to a low frequency of observed occurrence potentially caused by wellbore orientation. Microseismic data was used for identification of one of the reactivated natural fracture sets. An interesting phenomenon observed in the microseismic data trends was the low frequency of event occurrence within dense populations of open natural fracture swarms suggesting that zones of higher natural fracture intensities are capable of absorbing and transmitting energy resulting in lower levels of microseismicity. Thus currently open natural fractures could be challenging to detect using microseismic. Through this study I identified a significant variability in fracture intensity at a localized scale due to lithological composition and structural features. The complex faulting styles observed at the outcrop were utilized as an analog and verified by horizontal well log data and seismic volume interpretations creating a high resolution structural model for the subsurface. A lithofacies model was developed based on the well log, core, and seismic inversion analysis. These models combined served to accurately distribute fracture intensity information within the geological model for further use in DFN. As a product of this study, a workflow was developed to aid in fracture network model creation allowing for more intelligent decisions to be made during well planning and completion optimization aiming to improve recovery. A high resolution integrated discrete fracture network model serves to advance dynamic reservoir characterization in the subsurface at a sub-seismic scale resulting in improved reservoir characterization.
Ipsilateral intact fibula as a predictor of tibial plafond fracture pattern and severity.
Luk, Pamela C; Charlton, Timothy P; Lee, Jackson; Thordarson, David B
2013-10-01
The objective of this study was to determine whether there is a difference in fracture pattern and severity of comminution between tibial plafond fractures with and without associated fibular fractures using computed tomography (CT). We hypothesized that the presence of an intact fibula was predictive of increased tibial plafond fracture severity. This was a case control, radiographic review performed at a single level I university trauma center. Between November 2007 and July 2011, 104 patients with 107 operatively treated tibial pilon fractures and preoperative CT scans were identified: 70 patients with 71 tibial plafond fractures had associated fibular fractures, and 34 patients with 36 tibial plafond fractures had intact fibulas. Four criteria were compared between the 2 groups: AO/OTA classification of distal tibia fractures, Topliss coronal and sagittal fracture pattern classification, plafond region of greatest comminution, and degree of proximal extension of fracture line. The intact fibula group had greater percentages of AO/OTA classification B2 type (5.5 vs 0, P = .046) and B3 type (52.8 vs 28.2, P = .013). Conversely, the percentage of AO/OTA classification C3 type was greater in the fractured fibula group (53.5 vs 30.6, P = .025). Evaluation using the Topliss sagittal and coronal classifications revealed no difference between the 2 groups (P = .226). Central and lateral regions of the plafond were the most common areas of comminution in fractured fibula pilons (32% and 31%, respectively). The lateral region of the plafond was the most common area of comminution in intact fibula pilon fractures (42%). There was no statistically significant difference (P = .71) in degree of proximal extension of fracture line between the 2 groups. Tibial plafond fractures with intact fibulas were more commonly associated with AO/OTA classification B-type patterns, whereas those with fractured fibulas were more commonly associated with C-type patterns. An intact fibula may be predictive of less comminution of the plafond. The lateral and central regions of the plafond were the most common areas of comminution in tibial plafond fractures, regardless of fibular status. Level III, case control study.
Wang, Monan; Zhang, Kai; Yang, Ning
2018-04-09
To help doctors decide their treatment from the aspect of mechanical analysis, the work built a computer assisted optimal system for treatment of femoral neck fracture oriented to clinical application. The whole system encompassed the following three parts: Preprocessing module, finite element mechanical analysis module, post processing module. Preprocessing module included parametric modeling of bone, parametric modeling of fracture face, parametric modeling of fixed screw and fixed position and input and transmission of model parameters. Finite element mechanical analysis module included grid division, element type setting, material property setting, contact setting, constraint and load setting, analysis method setting and batch processing operation. Post processing module included extraction and display of batch processing operation results, image generation of batch processing operation, optimal program operation and optimal result display. The system implemented the whole operations from input of fracture parameters to output of the optimal fixed plan according to specific patient real fracture parameter and optimal rules, which demonstrated the effectiveness of the system. Meanwhile, the system had a friendly interface, simple operation and could improve the system function quickly through modifying single module.
NASA Astrophysics Data System (ADS)
Alfataierge, Ahmed
Hydrocarbon recovery rates within the Niobrara Shale are estimated as low as 2-8%. These recovery rates are controlled by the ability to effectively hydraulic fracture stimulate the reservoir using multistage horizontal wells. Subsequent to any mechanical issues that affect production from lateral wells, the variability in production performance and reserve recovery along multistage lateral shale wells is controlled by the reservoir heterogeneity and its consequent effect on hydraulic fracture stimulation efficiency. Using identical stimulation designs on a number of wells that are as close as 600ft apart can yield variable production and recovery rates due to inefficiencies in hydraulic fracture stimulation that result from the variability in elastic rock properties and in-situ stress conditions. As a means for examining the effect of the geological heterogeneity on hydraulic fracturing and production within the Niobrara Formation, a 3D geomechanical model is derived using geostatistical methods and volumetric calculations as an input to hydraulic fracture stimulation. The 3D geomechanical model incorporates the faults, lithological facies changes and lateral variation in reservoir properties and elastic rock properties that best represent the static reservoir conditions pre-hydraulic fracturing. Using a 3D numerical reservoir simulator, a hydraulic fracture predictive model is generated and calibrated to field diagnostic measurements (DFIT) and observations (microseismic and 4D/9C multicomponent time-lapse seismic). By incorporating the geological heterogeneity into the 3D hydraulic fracture simulation, a more representative response is generated that demonstrate the variability in hydraulic fracturing efficiency along the lateral wells that will inevitability influence production performance. Based on the 3D hydraulic fracture simulation results, integrated with microseismic observations and 4D/9C time-lapse seismic analysis (post-hydraulic fracturing & post production), the variability in production performance within the Niobrara Shale wells is shown to significantly be affected by the lateral variability in reservoir quality, well and stage positioning relative to the target interval, and the relative completion efficiency. The variation in reservoir properties, faults, rock strength parameters, and in-situ stress conditions are shown to influence and control the hydraulic fracturing geometry and stimulation efficiency resulting in complex and isolated induced fracture geometries to form within the reservoir. This consequently impacts the effective drainage areas, production performance and recovery rates from inefficiently stimulated horizontal wells. The 3D simulation results coupled with the 4D seismic interpretations illustrate that there is still room for improvement to be made in optimizing well spacing and hydraulic fracturing efficiency within the Niobrara Formation. Integrated analysis show that the Niobrara reservoir is not uniformly stimulated. The vertical and lateral variability in rock properties control the hydraulic fracturing efficiency and geometry. Better production is also correlated to higher fracture conductivity. 4D seismic interpretation is also shown to be essential for the validation and calibration hydraulic fracture simulation models. The hydraulic fracture modeling also demonstrations that there is bypassed pay in the Niobrara B chalk resulting from initial Niobrara C chalk stimulation treatments. Forward modeling also shows that low pressure intervals within the Niobrara reservoir influence hydraulic fracturing and infill drilling during field development.
Figliuzzi, M M; Giudice, A; Fortunato, L
2017-01-01
Aim . This study aims to explain the main steps that characterize the implant-prosthetic rehabilitation in complex combined dental and maxillofacial trauma. Material and Methods . A 20-year-old patient reported an extensive facial trauma which also involved the alveolar process of the maxillary bone. The patient reported a maxillofacial fracture and the loss of teeth 1.3, 1.2, 1.1, and 2.1. A "Le Fort" type 2 fracture was also reported, with the malar bone involvement. After reduction and containment of bone fractures, through appropriate mounting plates, appropriate functional and aesthetic rehabilitation of the patient were replaced thanks to a temporary removable prosthesis. After 6 months, the patient performed numerous clinical investigations, aimed at a proper planning of implant-prosthetic rehabilitation of the upper dental arch. Conclusion . With the planning of the case, as well as respecting the surrounding biological structures, the surgery of implants can be carried out with the most appropriate procedure. Lastly, new dental implants with highly bioactive surfaces have been developed, providing an excellent and rapid bone integration.
Henk, Henry J; Kaura, Satyin; Teitelbaum, April
2012-01-01
For patients with bone metastases, skeletal-related events including fracture are common, can cause considerable morbidity, and may reduce overall survival (OS). This retrospective analysis assessed the effect of Zometa (zoledronic acid, ZOL), an intravenous bisphosphonate (IV-BP), on fracture risk and OS in patients with bone metastases from lung cancer (LC). (Zometa is a registered trademark of Novartis Pharmaceuticals Corporation, USA.) A claims-based analysis using commercial and Medicare Advantage data from >45 US managed-care plans was used to evaluate the association between fracture risk and treatment persistency (31-90, 91-180, 181-365, and ≥366 days) and follow-up duration in LC patients diagnosed with bone metastases between 01/01/2001 and 12/31/2006 and treated with ZOL or without (no IV-BP). Persistency was defined as the absence of a >45-day gap between ZOL treatments. Analysis of variance tests were used to compare follow-up duration, a proxy for OS, between ZOL persistency groups. The effect of time to treatment with ZOL was also assessed. In 9874 LC patients with bone metastases (n = 1090 ZOL; n = 8784 no IV-BP) the unadjusted relative fracture risk was reduced by 40% with ZOL vs no IV-BP; fracture risk decreased consistently with increasing duration of ZOL treatment. Even short-term (31-90 days) ZOL significantly reduced fracture risk (47%) vs no IV-BP (p = 0.005) with adjustment for differences in demographic and clinical characteristics. Delaying ZOL until after bone metastases were diagnosed significantly increased fracture risk (p = 0.0017). For a sub-set of patients included in a survival analysis (n = 550 ZOL; n = 4512 no IV-BP), mortality was significantly lower (mean, 38.6 vs 46.8 deaths/100 person-years; p = 0.038) in those treated with ZOL vs no IV-BP. Interpretation of this claims-based analysis must be tempered by the inherent limitations of observational data, such as limited clinical information and the ability to control for prognostic factors. This retrospective analysis demonstrates that LC patients with bone metastases receiving ZOL had significantly reduced risk of fracture (p = 0.005) and death (p < 0.038) vs patients receiving no IV-BP. Longer ZOL persistency consistently yielded better outcomes, with ≥12 months' treatment producing the greatest benefit.
Strontium ranelate: short- and long-term benefits for post-menopausal women with osteoporosis
2008-01-01
Strontium ranelate is a bone-seeking element that has been assessed in post-menopausal osteoporosis in two large double-blind, placebo-controlled studies. This treatment is able to decrease the risk of vertebral fractures, by 41% over 3 yrs, and by 49% within the first year of treatment. This risk of non-vertebral fractures is decreased by 16% and, in patients at high risk for such a fracture, the risk of hip fracture is decreased by 36% over 3 yrs. Recent 5-yr data from these double-blind, placebo-controlled studies show that the anti-fracture efficacy is maintained over time. Treatment efficacy with strontium ranelate has been documented across a wide range of patient profiles: age, number of prevalent vertebral fractures, BMI, as well as family history of osteoporosis and addiction to smoking are not determinants of anti-fracture efficacy. During these clinical trials, safety was good. Its large spectrum of efficacy allows the use of strontium ranelate in the different subgroups of patients with post-menopausal osteoporosis. PMID:18556647
Vernon, J.H.; Paillet, F.L.; Pedler, W.H.; Griswold, W.J.
1993-01-01
Wellbore geophysical techniques were used to characterize fractures and flow in a bedrock aquifer at a site near Blackwater Brook in Dover, New Hampshire. The primary focus ofthis study was the development of a model to assist in evaluating the area surrounding a planned water supply well where contaminants introduced at the land surface might be induced to flow towards a pumping well. Well logs and geophysical surveys used in this study included lithologic logs based on examination of cuttings obtained during drilling; conventional caliper and natural gamma logs; video camera and acoustic televiewer surveys; highresolution vertical flow measurements under ambient conditions and during pumping; and borehole fluid conductivity logs obtained after the borehole fluid was replaced with deionized water. These surveys were used for several applications: 1) to define a conceptual model of aquifer structure to be used in groundwater exploration; 2) to estimate optimum locations for test and observation wells; and 3) to delineate a wellhead protection area (WHPA) for a planned water supply well. Integration of borehole data with surface geophysical and geological mapping data indicated that the study site lies along a northeast-trending intensely fractured contact zone between surface exposures of quartz monzonite and metasedimentary rocks. Four of five bedrock boreholes at the site were estimated to produce more than 150 gallons per minute (gpm) (568 L/min) of water during drilling. Aquifer testing and other investigations indicated that water flowed to the test well along fractures parallel to the northeast-trending contact zone and along other northeast and north-northwest-trending fractures. Statistical plots of fracture strikes showed frequency maxima in the same northeast and north-northwest directions, although additional maxima occurred in other directions. Flowmeter surveys and borehole fluid conductivity logging after fluid replacement were used to identify water-producing zones in the boreholes; fractures associated with inflow into boreholes showed a dominant northeast orientation. Borehole fluid conductivity logging after fluid replacement also gave profiles of such water-quality parameters as fluid electrical conductivity (FEC), pH, temperature, and oxidation-reduction potential, strengthening the interpretation of crossconnection of boreholes by certain fracture zones. The results of this study showed that the application of these borehole geophysical techniques at the Blackwater Brook site led to an improved understanding of such parameters as fracture location, attitude, flow direction and velocity, and water quality; all of which are important in the determination of a WHPA.
Dairy product consumption and risk of hip fracture: a systematic review and meta-analysis.
Bian, Shanshan; Hu, Jingmin; Zhang, Kai; Wang, Yunguo; Yu, Miaohui; Ma, Jie
2018-01-22
Dairy product consumption may affect the risk of hip fracture, but previous studies have reported inconsistent findings. The primary aim of our meta-analysis was to examine and quantify the potential association of dairy product consumption with risk of hip fracture. We searched the databases of PubMed and EMBASE for relevant articles from their inception through April 17, 2017. The final analysis included 10 cohort studies and 8 case-control studies. Random-effects models were used to estimate the pooled risk. Subgroup and dose-response analyses were conducted to explore the relationships between the consumption of milk and the risk of hip fracture. After pooling the data from the included studies, the summary relative risk (RR) for hip fracture for highest versus lowest consumption were 0.91 (95% CI: 0.74-1.12), 0.75 (95% CI: 0.66-0.86), 0.68 (95% CI: 0.61-0. 77), 1.02 (95% CI: 0.93-1.12) for milk, yogurt, cheese, and total dairy products in cohort studies, respectively. Higher milk consumption [Odds ratio (OR), 0.71, 95% CI: 0.55-0. 91] was associated with lower risk of hip fracture for highest versus lowest consumption in case-control studies. After quantifying the specific dose of milk, the summary RR/OR for an increased milk consumption of 200 g/day was 1.00 (95% CI: 0.94-1.07), and 0.89 (95%CI: 0.64-1.24) with significant heterogeneity for cohort and case-control studies, respectively; There was a nonlinear association between milk consumption and hip fracture risk in cohort, and case-control studies. Our findings indicate that consumption of yogurt and cheese was associated with lower risk of hip fracture in cohort studies. However, the consumption of total dairy products and cream was not significantly associated with the risk of hip fracture. There was insufficient evidence to deduce the association between milk consumption and risk of hip fracture. A lower threshold of 200 g/day milk intake may have beneficial effects, whereas the effects of a higher threshold of milk intake are unclear.
NASA Astrophysics Data System (ADS)
Newman, Brent D.; Campbell, Andrew R.; Norman, David I.; Ringelberg, David B.
1997-05-01
Fractures are unique environments that can concentrate the flow of water, nutrients, and contaminants. As such, fractures play an important role in controlling the flux of various substances into and through the vadose zone. Calcite fracture fillings are present in the near surface in the Bandelier Tuff Formation at Los Alamos, New Mexico, and provide a record of the geochemical and hydrologic processes that have occurred in fractures. The objective of this study was to examine calcite fracture fills in order to improve understanding of processes within fractures, and in particular those that lead to precipitation of calcite. Samples of calcite fillings were collected from vertical and horizontal fractures exposed in a shallow waste-burial pit. Scanning electron microscopy show morphologies which suggest that plants, fungi, and bacteria were important in the precipitation process. Quadrupole mass spectrometric analyses of fluid inclusion gases show predominantly methane (17-99%) and little to no oxygen (0-8%), suggesting the development of anaerobic conditions in the fractures. Ester-linked phospholipid biomarkers are evidence for a diverse microbial community in the fractures, and the presence of di-ether lipids indicate that the methane was generated by anaerobic bacteria. The calcite fillings apparently resulted from multiple biological and chemical processes in which plant roots in the fractures were converted to calcite. Roots grew into the fractures, eventually died, and were decomposed by bacteria and fungi. Anaerobic gases were generated from encapsulated organic material within the calcite via microbial decomposition, or were generated by microbes simultaneously with calcite precipitation. It is likely that the biological controls on calcite formation that occurred in the Los Alamos fractures also occurs in soils, and may explain the occurrence of other types of pedogenic calcites.
Hip fracture risk and safety with alendronate treatment in the oldest-old.
Axelsson, K F; Wallander, M; Johansson, H; Lundh, D; Lorentzon, M
2017-12-01
There is high evidence for secondary prevention of fractures, including hip fracture, with alendronate treatment, but alendronate's efficacy to prevent hip fractures in the oldest-old (≥80 years old), the population with the highest fracture risk, has not been studied. To investigate whether alendronate treatment amongst the oldest-old with prior fracture was related to decreased hip fracture rate and sustained safety. Using a national database of men and women undergoing a fall risk assessment at a Swedish healthcare facility, we identified 90 795 patients who were 80 years or older and had a prior fracture. Propensity score matching (four to one) was then used to identify 7844 controls to 1961 alendronate-treated patients. The risk of incident hip fracture was investigated with Cox models and the interaction between age and treatment was investigated using an interaction term. The case and control groups were well balanced in regard to age, sex, anthropometrics and comorbidity. Alendronate treatment was associated with a decreased risk of hip fracture in crude (hazard ratio (HR) 0.62 (0.49-0.79), P < 0.001) and multivariable models (HR 0.66 (0.51-0.86), P < 0.01). Alendronate was related to reduced mortality risk (HR 0.88 (0.82-0.95) but increased risk of mild upper gastrointestinal symptoms (UGI) (HR 1.58 (1.12-2.24). The alendronate association did not change with age for hip fractures or mild UGI. In old patients with prior fracture, alendronate treatment reduces the risk of hip fracture with sustained safety, indicating that this treatment should be considered in these high-risk patients. © 2017 The Authors. Journal of Internal Medicine published by John Wiley & Sons Ltd on behalf of Association for Publication of The Journal of Internal Medicine.
Jacob, L; Kostev, K
2017-04-01
Two thousand eight hundred ninety-four children and adolescents treated by 243 pediatricians were analyzed. Patients receiving attention deficit hyperactivity disorder (ADHD) medications were at a lower risk of fractures than patients without ADHD medications. The strongest impact was in the age group of 6-9 years. Finally, there was a significant association between therapy duration and fracture risk. The aim of this study was to analyze the impact of ADHD therapy on fracture risk in children treated by German pediatricians. Children and adolescents initially diagnosed with ADHD and fractures between 2010 and 2015 were identified by 243 pediatricians. In this nested case-control study, each ADHD case with a fracture was matched (1:1) to an ADHD control without a fracture for age, gender, index year, and physician. In total, 2894 individuals were available for analysis. The main outcome of the study was the risk of fracture as a function of ADHD therapy. Multivariate logistic regression models were created to determine the effect of ADHD therapy on the risk of fracture in the entire population and in three age-specific subgroups. Patients receiving ADHD medications were at a lower risk of fracture than patients without ADHD medications (OR = 0.61). The impact of ADHD therapy on the risk of fracture was stronger in the age group of 6-9 years (OR = 0.41) than in the age groups of 10-13 years (OR = 0.68) and 14-17 years (OR = 0.74). Finally, a significant correlation was found between therapy duration and fracture risk (OR = 0.71 per month). ADHD therapy was associated with a decrease in the risk of fracture in children and adolescents treated by German pediatricians.
Wellman, Tristan; Shapiro, Allen M.; Hill, Mary C.
2009-01-01
While it is widely recognized that highly permeable 'large-scale' fractures dominate chemical migration in many fractured aquifers, recent studies suggest that the pervasive 'small-scale' fracturing once considered of less significance can be equally important for characterizing the spatial extent and residence time associated with transport processes. A detailed examination of chemical migration through fracture-controlled aquifers is used to advance this conceptual understanding. The influence of fracture structure is evaluated by quantifying the effects to transport caused by a systematic removal of fractures from three-dimensional discrete fracture models whose attributes are derived from geologic and hydrologic conditions at multiple field sites. Results indicate that the effects to transport caused by network simplification are sensitive to the fracture network characteristics, degree of network simplification, and plume travel distance, but primarily in an indirect sense since correlation to individual attributes is limited. Transport processes can be 'enhanced' or 'restricted' from network simplification meaning that the elimination of fractures may increase or decrease mass migration, mean travel time, dispersion, and tailing of the concentration plume. The results demonstrate why, for instance, chemical migration may not follow the classic advection-dispersion equation where dispersion approximates the effect of the ignored geologic structure as a strictly additive process to the mean flow. The analyses further reveal that the prediction error caused by fracture network simplification is reduced by at least 50% using the median estimate from an ensemble of simplified fracture network models, and that the error from network simplification is at least 70% less than the stochastic variability from multiple realizations. Copyright 2009 by the American Geophysical Union.
Cattaneo, C; Marinelli, E; Di Giancamillo, A; Di Giancamillo, M; Travetti, O; Vigano', L; Poppa, P; Porta, D; Gentilomo, A; Grandi, M
2006-12-20
Skeletal injuries are often strong indicators of child abuse and their detection is therefore crucial. The aim of this study was to compare the sensitivity of three diagnostic approaches, namely autopsy, traditional (conventional) radiology, and computed tomography on "battered" piglets, in order to verify the sensitivity of each method, with respect to the true number of bone fractures assessed once the piglet was skeletonised (osteological control). Four newborn cadaver piglets who had died from natural causes were severely beaten post-mortem in every district of the body. Traditional radiography, computed tomography (CT) and autopsy were performed. The piglet was then macerated until skeletonised and the number of all fractures present recorded (osteological control). On the cranium, traditional radiology revealed only 35% circa of actual fractures, autopsy detected only 31% (P<0.01 for both comparisons versus osteological control), whereas CT imaging detected all fractures actually present. For ribs, radiology detected only 47% of all fractures present, and autopsy 65% circa (P>0.05 for both comparisons versus osteological control), while CT scans detected 34% (P<0.01). In suspected cases of fatal child abuse, we suggest that the bones of specific districts be directly analysed either at autopsy or by collecting specific diagnostic sites, such as parts of the rib cage, and subjecting them to maceration. The removed areas could be replaced with artificial material for cosmetic purposes. The authors stress the importance of combined radiological, CT scan, autopsy and osteological survey in the detection of perimortem bone fractures.
Leung, K S; Li, C Y; Tse, Y K; Choy, T K; Leung, P C; Hung, V W Y; Chan, S Y; Leung, A H C; Cheung, W H
2014-06-01
This study is a prospective cluster-randomized controlled clinical trial involving 710 elderly subjects to investigate the long-term effects of low-magnitude high-frequency vibration (LMHFV) on fall and fracture rates, muscle performance, and bone quality. The results confirmed that LMHFV is effective in reducing fall incidence and enhancing muscle performance in the elderly. Falls are direct causes of fragility fracture in the elderly. LMHFV has been shown to improve muscle function and bone quality. This study is to investigate the efficacy of LMHFV in preventing fall and fractures among the elderly in the community. A cluster-randomized controlled trial was conducted with 710 postmenopausal females over 60 years. A total of 364 participants received daily 20 min LMHFV (35 Hz, 0.3 g), 5 days/week for 18 months; 346 participants served as control. Fall or fracture rate was taken as the primary outcome. Also, quadriceps muscle strength, balancing abilities, bone mineral density (BMD), and quality of life (QoL) assessments were done at 0, 9, and 18 months. With an average of 66.0% compliance in the vibration group, 18.6% of 334 vibration group subjects reported fall or fracture incidences compared with 28.7% of 327 in the control (adjusted HR = 0.56, p = 0.001). The fracture rate of vibration and control groups were 1.1 and 2.3 % respectively (p = 0.171). Significant improvements were found in reaction time, movement velocity, and maximum excursion of balancing ability assessment, and also the quadriceps muscle strength (p < 0.001). No significant differences were found in the overall change of BMD. Minimal adverse effects were documented. LMHFV is effective in fall prevention with improved muscle strength and balancing ability in the elderly. We recommend its use in the community as an effective fall prevention program and to decrease related injuries.
Cerebral fat embolism: pulmonary contusion is a more important etiology than long bone fractures.
Aydin, M D; Akçay, F; Aydin, N; Gündogdu, C
2005-01-01
Lipid embolism is a serious and life-threatening problem and usually arises as a complication of severe trauma associated with long bone or pelvic fractures. It is generally thought that fat droplets enter the circulation at the site of fracture. In the systemic circulation, they become emboli to brain, kidney and other areas. Lipids are absorbed from the intestinal tract and transported into pulmonary tissue via thoracic duct and exposed to first catabolic procedures in the lungs. We have predicted that systemic lipid embolism may not occur unless bone fractures lead to pulmonary injury. This study was planned to investigate this hypothesis with respect to the role of pulmonary contusion and long bone fractures in the formation of cerebral fat embolism. Twenty male hybrid rabbits were included in this study. Pulmonary contusion was performed on half of the rabbits (n = 10) and femur fracture was applied to the remaining ones (n = 10). Ten days after procedure, all rabbits were sacrificed. Brain specimens were taken by frozen-section method and stained with Sudan black. Intraarteriolar lipid particles in the brain were examined microscopically. Cerebral fat embolism was detected in seven animals exposed to pulmonary contusion and only in one animal exposed to femur fracture. The mean number of branches of middle cerebral artery at midparietal level occluded with fat particles were higher in the pulmonary contusion group than in the long bone fracture group. In conclusion, we found that pulmonary contusion had more deleterious effects than long bone fracture in the formation of cerebral fat embolism.
The Role of Minimally Invasive Plate Osteosynthesis in Rib Fixation: A Review
Bemelman, Michael; van Baal, Mark; Yuan, Jian Zhang; Leenen, Luke
2016-01-01
More than a century ago, the first scientific report was published about fracture fixation with plates. During the 1950’s, open reduction and plate fixation for fractures were standardized by the founders of Arbeitsgemeinschaft für osteosynthesefragen/Association for the Study of Internal Fixation. Since the introduction of plate fixation for fractures, several plates and screws have been developed, all with their own characteristics. To accomplice more fracture stability, it was thought the bigger the plate, the better. The counter side was a compromised blood supply of the bone, often resulting in bone necrosis and ultimately delayed or non-union. With the search and development of new materials and techniques for fracture fixation, less invasive procedures have become increasingly popular. This resulted in the minimally invasive plate osteosynthesis (MIPO) technique for fracture fixation. With the MIPO technique, procedures could be performed with smaller incisions and thus with less soft tissue damage and a better preserved blood supply. The last 5 years rib fixation has become increasingly popular, rising evidence has become available suggesting that surgical rib fixation improves outcome of patients with a flail chest or isolated rib fractures. Many surgical approaches for rib fixation have been described in the old literature, however, most of these techniques are obscure nowadays. Currently mostly large incisions with considerable surgical insult are used to stabilize rib fractures. We think that MIPO deserves a place in the surgical treatment of rib fractures. We present the aspects of diagnosis, preoperative planning and operative techniques in regard to MIPO rib fixation. PMID:26889439
3D printing utility for surgical treatment of acetabular fractures.
Chana Rodríguez, F; Pérez Mañanes, R; Narbona Cárceles, F J; Gil Martínez, P
2018-05-25
Preoperative 3D modelling enables more effective diagnosis and simulates the surgical procedure. We report twenty cases of acetabular fractures with preoperative planning performed by pre-contouring synthesis plates on a 3D printed mould obtained from a computarized tomography (CT) scan. The mould impression was made with the DaVinci 1.0 printer model (XYZ Printing). After obtaining the printed hemipelvis, we proceeded to select the implant size (pelvic Matta system, Stryker ® ) that matched the characteristics of the fracture and the approach to be used. Printing the moulds took a mean of 385minutes (322-539), and 238grams of plastic were used to print the model (180-410). In all cases, anatomic reduction was obtained and intra-operative changes were not required in the initial contouring of the plates. The time needed to perform the full osteosynthesis, once the fracture had been reduced was 16.9minutes (10-24). In one case fixed with two plates, a postoperative CT scan showed partial contact of the implant with the surface of the quadrilateral plate. In the remaining cases, the contact was complete. In conclusion, our results suggest that the use of preoperative planning, by printing 3D mirror imaging models of the opposite hemipelvis and pre-contouring plates over the mould, might effectively achieve a predefined surgical objective and reduce the inherent risks in these difficult procedures. Copyright © 2018. Publicado por Elsevier España, S.L.U.
Analysis of the groundwater monitoring controversy at the Pavillion, Wyoming natural gas field.
Stephens, Daniel B
2015-01-01
The U.S. Environmental Protection Agency (EPA) was contacted by citizens of Pavillion, Wyoming 6 years ago regarding taste and odor in their water wells in an area where hydraulic fracturing operations were occurring. EPA conducted a field investigation, including drilling two deep monitor wells, and concluded in a draft report that constituents associated with hydraulic fracturing had impacted the drinking water aquifer. Following extensive media coverage, pressure from state and other federal agencies, and extensive technical criticism from industry, EPA stated the draft report would not undergo peer review, that it would not rely on the conclusions, and that it had relinquished its lead role in the investigation to the State of Wyoming for further investigation without resolving the source of the taste and odor problem. Review of the events leading up to EPA's decision suggests that much of the criticism could have been avoided through improved preproject planning with clear objectives. Such planning would have identified the high national significance and potential implications of the proposed work. Expanded stakeholder involvement and technical input could have eliminated some of the difficulties that plagued the investigation. However, collecting baseline groundwater quality data prior to initiating hydraulic fracturing likely would have been an effective way to evaluate potential impacts. The Pavillion groundwater investigation provides an excellent opportunity for improving field methods, report transparency, clarity of communication, and the peer review process in future investigations of the impacts of hydraulic fracturing on groundwater. © 2014, National Ground Water Association.
Kutina, J.; Carter, William D.; Lopez, F.X.
1978-01-01
The role of east-west fracture zones in South America is discussed with regard to global fracturing and the motion of lithospheric plates. A set of major NW-trending lineaments has been derived which show a tendency to be spaced equidistantly and may correspond to a set of east-west fractures in the "pre-drift" position of the South American plate. Statistical analysis of linears in the ERTS-mosaics shows that NW-fractures are also among the most important ones in the Andes region, suggesting that the above major lineaments extend into the basement of the Andes. Some of the old major fractures, trending east-west in the present orientation of South America, are discussed and their NE orientation in the pre-drift position of the plate is considered. An example of structural control of ore deposition in the Brazilian Shield is presented, using the maps of the RADAM Project. It is concluded that the small tin-bearing granitic bodies concentrated in the region of Sao Felix do Xingu in the state of Para represent upper parts of an unexposed granitoid massif which is controlled by the intersection of a major east-west fracture zone probably represents westward extension of the Patos Lineament of the easternmost part of Brazil, connected with the east-west fracture zone of the Para state through the basement of the Maranhao Basin (Sineclise do Maranhao-Piaui). It is expected that the proposed "Patos-Para Lineament" extends further westward and may similarly control, at intersections with fractures of other trends, some mineralization centers in the western part of the state of Para and in the state of Amazonas.
Sommar, Johan Nilsson; Pettersson-Kymmer, Ulrika; Lundh, Thomas; Svensson, Olle; Hallmans, Göran; Bergdahl, Ingvar A
2014-02-01
Several studies have investigated the relation between bone mass density and cadmium exposure, but only few studies have been performed on fractures and biomarkers of cadmium. This study analyzed the association between hip fracture risk and cadmium in erythrocytes (Ery-Cd). Prospective samples from the Northern Sweden Health and Disease Study's biobank were used for 109 individuals who later in life had sustained a low-trauma hip fracture, matched with two controls of the same age and gender. The mean concentration of Ery-Cd (±SD) in case samples was 1.3 ± 1.4 versus 0.9 ± 1.0 μg/L in controls. The odds ratio (OR) was 1.63 [95% confidence interval (CI) 1.10-2.42] for suffering a hip fracture for each microgram per liter increase in Ery-Cd. However, when taking smoking into consideration (never, former, or current), neither Ery-Cd nor smoking showed a statistically significant increase in fracture risk. Using multiple conditional logistic regression with BMI, height, and smoking, the estimated OR for a 1-μg/L increase in Ery-Cd was 1.52 (95% CI 0.77-2.97). Subgroup analysis showed an increased fracture risk among women (OR = 1.94, 95% CI 1.18-3.20, for a 1 μg/L increase), which also remained in the multiple analysis (OR = 3.33, 95% CI 1.29-8.56). This study shows that fracture risk is associated with Ery-Cd. It is, however, not possible to draw firm conclusions on whether cadmium is the causal factor or whether other smoking-related factors cause this association. Subgroup analysis shows that cadmium is a risk factor for hip fracture among women.
Inhibitors of hydroxymethylglutaryl-coenzyme A reductase and risk of fracture among older women.
Chan, K A; Andrade, S E; Boles, M; Buist, D S; Chase, G A; Donahue, J G; Goodman, M J; Gurwitz, J H; LaCroix, A Z; Platt, R
2000-06-24
Inhibitors of hydroxymethylglutaryl-coenzyme A reductase (statins) increase new bone formation in rodents and in human cells in vitro. Statin use is associated with increased bone mineral density of the femoral neck. We undertook a population-based case-control study at six health-maintenance organisations in the USA to investigate further the relation between statin use and fracture risk among older women. We investigated women aged 60 years or older. Exposure, outcome, and confounder information was obtained from automated claims and pharmacy data from October, 1994, to September, 1997. Cases had an incident diagnosis of non-pathological fracture of the hip, humerus, distal tibia, wrist, or vertebrae between October, 1996, and September, 1997. Controls had no fracture during this period. We excluded women with records of dispensing of drugs to treat osteoporosis. There were 928 cases and 2747 controls. Compared with women who had no record of statin dispensing during the previous 2 years, women with 13 or more statin dispensings during this period had a decreased risk of non-pathological fracture (odds ratio 0.48 [95% CI 0.27-0.83]) after adjustment for age, number of hospital admissions during the previous year, chronic disease score, and use of non-statin lipid-lowering drugs. No association was found between fracture risk and fewer than 13 dispensings of statins or between fracture risk and use of non-statin lipid-lowering drugs. Statins seem to be protective against non-pathological fracture among older women. These findings are compatible with the hypothesis that statins increase bone mineral density in human beings and thereby decrease the risk of osteoporotic fractures.
NASGRO(registered trademark): Fracture Mechanics and Fatigue Crack Growth Analysis Software
NASA Technical Reports Server (NTRS)
Forman, Royce; Shivakumar, V.; Mettu, Sambi; Beek, Joachim; Williams, Leonard; Yeh, Feng; McClung, Craig; Cardinal, Joe
2004-01-01
This viewgraph presentation describes NASGRO, which is a fracture mechanics and fatigue crack growth analysis software package that is used to reduce risk of fracture in Space Shuttles. The contents include: 1) Consequences of Fracture; 2) NASA Fracture Control Requirements; 3) NASGRO Reduces Risk; 4) NASGRO Use Inside NASA; 5) NASGRO Components: Crack Growth Module; 6) NASGRO Components:Material Property Module; 7) Typical NASGRO analysis: Crack growth or component life calculation; and 8) NASGRO Sample Application: Orbiter feedline flowliner crack analysis.
Linear elastic fracture mechanics primer
NASA Technical Reports Server (NTRS)
Wilson, Christopher D.
1992-01-01
This primer is intended to remove the blackbox perception of fracture mechanics computer software by structural engineers. The fundamental concepts of linear elastic fracture mechanics are presented with emphasis on the practical application of fracture mechanics to real problems. Numerous rules of thumb are provided. Recommended texts for additional reading, and a discussion of the significance of fracture mechanics in structural design are given. Griffith's criterion for crack extension, Irwin's elastic stress field near the crack tip, and the influence of small-scale plasticity are discussed. Common stress intensities factor solutions and methods for determining them are included. Fracture toughness and subcritical crack growth are discussed. The application of fracture mechanics to damage tolerance and fracture control is discussed. Several example problems and a practice set of problems are given.
D'Souza, Neil; Mainprize, James; Edwards, Glenn; Binhammer, Paul; Antonyshyn, Oleh
2015-01-01
The facial fracture biomodel is a three-dimensional physical prototype of an actual facial fracture. The biomodel can be used as a novel teaching tool to facilitate technical skills training in fracture reduction and fixation, but more importantly, can help develop diagnostic and management competence. To introduce the 'facial fracture biomodel' as a teaching aid, and to provide preliminary evidence of its effectiveness in teaching residents the principles of panfacial fracture repair. Computer three-dimensional image processing and rapid prototyping were used to generate an accurate physical model of a panfacial fracture, mounted in a silicon 'soft tissue' base. Senior plastic surgery residents in their third, fourth and fifth years of training across Canada were invited to participate in a workshop using this biomodel to simulate panfacial fracture repair. A short didactic presentation outlining the 'patient's' clinical and radiological findings, and key principles of fracture repair, was given by a consultant plastic surgeon before the exercise. The residents completed a pre- and postbiomodel questionnaire soliciting information regarding background, diagnosis and management, and feedback. A total of 29 residents completed both pre- and postbiomodel questionnaires. Statistically significant results were found in the following areas: diagnosis of all fracture patterns (P=8.2×10(-7) [t test]), choice of incisions for adequate exposure (P=0.04 [t test]) and identifying sequence of repair (P=0.019 [χ(2) test]). Subjective evaluation of workshop effectiveness revealed a statistically significant increase in 'comfort level' only among third year trainees. Overall, positive feedback was reported among all participants. Biomodelling is a promising ancillary teaching aid that can assist in teaching residents technical skills, as well as how to assess and plan surgical repair.
Partial proximal tibia fractures
Raschke, Michael J.; Kittl, Christoph; Domnick, Christoph
2017-01-01
Partial tibial plateau fractures may occur as a consequence of either valgus or varus trauma combined with a rotational and axial compression component. High-energy trauma may result in a more complex and multi-fragmented fracture pattern, which occurs predominantly in young people. Conversely, a low-energy mechanism may lead to a pure depression fracture in the older population with weaker bone density. Pre-operative classification of these fractures, by Müller AO, Schatzker or novel CT-based methods, helps to understand the fracture pattern and choose the surgical approach and treatment strategy in accordance with estimated bone mineral density and the individual history of each patient. Non-operative treatment may be considered for non-displaced intra-articular fractures of the lateral tibial condyle. Intra-articular joint displacement ⩾ 2 mm, open fractures or fractures of the medial condyle should be reduced and fixed operatively. Autologous, allogenic and synthetic bone substitutes can be used to fill bone defects. A variety of minimally invasive approaches, temporary osteotomies and novel techniques (e.g. arthroscopically assisted reduction or ‘jail-type’ screw osteosynthesis) offer a range of choices for the individual and are potentially less invasive treatments. Rehabilitation protocols should be carefully planned according to the degree of stability achieved by internal fixation, bone mineral density and other patient-specific factors (age, compliance, mobility). To avoid stiffness, early functional mobilisation plays a major role in rehabilitation. In the elderly, low-energy trauma and impression fractures are indicators for the further screening and treatment of osteoporosis. Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160067. Originally published online at www.efortopenreviews.org PMID:28630761
Measurement of Malrotation on Direct Radiography in Pediatric Distal Radius Fractures
Duymus, Tahir Mutlu; Mutlu, Serhat; Komur, Baran; Mutlu, Harun; Yucel, Bulent; Parmaksizoglu, Atilla Sancar
2016-01-01
Abstract The aim of this prospective study was to test a mathematical method of measuring the malrotation of pediatric distal radius fractures (PDRFs) from direct radiographs. A total of 70 pediatric patients who presented at the Emergency Department with a distal radius fracture were evaluated. For 38 selected patients conservative treatment for PDRF was planned. Anteroposterior and lateral radiographs were taken of all of the patients for comparison before and after reduction. Radius bone diameters were measured in the coronal and sagittal planes on the healthy and fractured sides. Using the diameter values on the healthy side and the new diameter values on the fractured side in the rotation formula, the degree of malrotation between the fracture ends was calculated. The mean follow-up period was 13.5 months. Patients’ mean age was 10.00 ± 3.19 years (range, 4–12 years). The rotation degree in the sagittal plane significantly differed between the proximal (26.52°±2.84°) and distal fracture ends (20.96°±2.73°) (P = 0.001). The rotation degree in the coronal plane significantly differed between the proximal (26.70°±2.38°) and distal fracture ends (20.26°±2.86°) (P = 0.001). The net rotation deformity of the fracture line was determined to be 5.55°± 3.54° on lateral radiographs and 5.44°± 3.35° on anteroposterior radiographs, no significant difference was observed between measurements (P >0.05). The malrotation deformity in PDRF occurs with greater rotation in the proximal fragment than in the distal fragment. The net rotation deformity created between the fracture ends can be calculated on direct radiographs. Level of Evidence: Diagnostic, Level II PMID:27149480
Validation of a new classification for periprosthetic shoulder fractures.
Kirchhoff, Chlodwig; Beirer, Marc; Brunner, Ulrich; Buchholz, Arne; Biberthaler, Peter; Crönlein, Moritz
2018-06-01
Successful treatment of periprosthetic shoulder fractures depends on the right strategy, starting with a well-structured classification of the fracture. Unfortunately, clinically relevant factors for treatment planning are missing in the pre-existing classifications. Therefore, the aim of the present study was to describe a new specific classification system for periprosthetic shoulder fractures including a structured treatment algorithm for this important fragility fracture issue. The classification was established, focussing on five relevant items, naming the prosthesis type, the fracture localisation, the rotator cuff status, the anatomical fracture region and the stability of the implant. After considering each single item, the individual treatment concept can be assessed in one last step. To evaluate the introduced classification, a retrospective analysis of pre- and post-operative data of patients, treated with periprosthetic shoulder fractures, was conducted by two board certified trauma surgery consultants. The data of 19 patients (8 male, 11 female) with a mean age of 74 ± five years have been analysed in our study. The suggested treatment algorithm was proven to be reliable, detected by good clinical outcome in 15 of 16 (94%) cases, where the suggested treatment was maintained. Only one case resulted in poor outcome due to post-operative wound infection and had to be revised. The newly developed six-step classification is easy to utilise and extends the pre-existing classification systems in terms of clinically-relevant information. This classification should serve as a simple tool for the surgeon to consider the optimal treatment for his patients.
Kotsianos, D; Rock, C; Wirth, S; Linsenmaier, U; Brandl, R; Fischer, T; Euler, E; Mutschler, W; Pfeifer, K J; Reiser, M
2002-01-01
To analyze a prototype mobile C-arm 3D image amplifier in the detection and classification of experimental tibial condylar fractures with multiplanar reconstructions (MPR). Human knee specimens (n = 22) with tibial condylar fractures were examined with a prototype C-arm (ISO-C-3D, Siemens AG), plain films (CR) and spiral CT (CT). The motorized C-arm provides fluoroscopic images during a 190 degrees orbital rotation computing a 119 mm data cube. From these 3D data sets MP reconstructions were obtained. All images were evaluated by four independent readers for the detection and assessment of fracture lines. All fractures were classified according to the Müller AO classification. To confirm the results, the specimens were finally surgically dissected. 97 % of the tibial condylar fractures were easily seen and correctly classified according to the Müller AO classification on MP reconstruction of the ISO-C-3D. There is no significant difference between ISO-C and CT in detection and correct classification of fractures, but ISO-CD-3D is significant by better than CR. The evaluation of fractures with the ISO-C is better than with plain films alone and comparable to CT scans. The three-dimensional reconstruction of the ISO-C can provide important information which cannot be obtained from plain films. The ISO-C-3D may be useful in planning operative reconstructions and evaluating surgical results in orthopaedic surgery of the limbs.
Pareja Sierra, T; Bartolomé Martín, I; Rodríguez Solís, J; Bárcena Goitiandia, L; Torralba González de Suso, M; Morales Sanz, M D; Hornillos Calvo, M
Due to its high prevalence and serious consequences it is very important to be well aware of factors that might be related to medical complications, mortality, hospital stay and functional recovery in elderly patients with hip fracture. A prospective study of a group of 130 patients aged over 75 years admitted for osteoporotic hip fracture. Their medical records, physical and cognitive status prior to the fall, fracture type and surgical treatment, medical complications and functional and social evolution after hospitalization were evaluated. Patients with greater physical disability, more severe cognitive impairment and those who lived in a nursing home before the fracture had worse functional recovery after surgery. Treatment with intravenous iron to reduce transfusions reduced hospital stay and improved walking ability. Infections and heart failure were the most frequent medical complications and were related to a longer hospital stay. The prescription of nutritional supplements for the patients with real indication improved their physical recovery after the hip fracture CONCLUSIONS: Evaluation of physical, cognitive and social status prior to hip fracture should be the basis of an individual treatment plan because of its great prognostic value. Multidisciplinary teams with continuous monitoring of medical problems should prevent and treat complications as soon as possible. Intravenous iron and specific nutritional supplements can improve functional recovery six months after hip fracture. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.
Minimizing damage to a propped fracture by controlled flowback procedures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robinson, B.M.; Holditch, S.A.; Whitehead, W.S.
1988-06-01
Severe fracture-conductivity damage can result from proppant crushing and/or proppant flowback into the wellbore. Such damage is often concentrated near the wellbore and can directly affect postfracture performance. Most of the time severe fracture-conductivity damage can be minimized by choosing the correct type of proppant for a particular well. In many cases, however, this is not enough. To minimize excessive crushing or to prevent proppant flowback, it is also necessary to control carefully the flowback of the well after the treatment. Specific procedures can be followed to minimize severe fracture-conductivity damage. These procedures involve controlling the rates at which loadmore » fluids are recovered and maximizing backpressure against the formation. These procedures require much more time and effort than is normally spent on postfracture cleanup; however, the efforts could result in better performance.« less
International Space Station Research Plan, Assembly Sequence Rev., F
2000-08-01
muscles ü Higher risk for bone fracture upon return to Earth ü Potential for “slipped discs” ü Diminished ability to quickly respond to emergencies...Office of Biological and Physical Research International Space Station Research Plan Assembly Sequence Rev. F, Aug. 2000l . , . Report...Organization Name(s) and Address(es) NASA, Office of Biological and Physical Research Performing Organization Report Number Sponsoring/Monitoring Agency
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jochen, J.E.; Hopkins, C.W.
1993-12-31
;Contents: Naturally fractured reservoir description; Geologic considerations; Shale-specific log model; Stress profiles; Berea reasearch; Benefits analysis; Summary of technologies; Novel well test methods; Natural fracture identification; Reverse drilling; Production data analysis; Fracture treatment quality control; Novel core analysis methods; and Shale well cleanouts.
Beattie, J Renwick; Feskanich, Diane; Caraher, M Clare; Towler, Mark R
2018-01-01
Studies have shown that Raman spectroscopic analysis of fingernail clippings can help differentiate between post-menopausal women who have and who have not suffered a fracture. However, all studies to date have been retrospective in nature, comparing the proteins in nails sourced from women, post-fracture. The objective of this study was to investigate the potential of a prospective test for hip fracture based on spectroscopic analysis of nail tissue. Archived toenail samples from post-menopausal women aged 50 to 63 years in the Nurses’ Health Study were obtained and analysed by Raman spectroscopy. Nails were matched case-controls sourced from 161 women; 82 who underwent a hip fracture up to 20 years after nail collection and 81 age-matched controls. A number of clinical risk factors (CRFs) from the Fracture Risk Assessment (FRAX) tool had been assessed at toenail collection. Using 80% of the spectra, models were developed for increasing time periods between nail collection and fracture. Scores were calculated from these models for the other 20% of the sample and the ability of the score to predict hip fracture was tested in model with and without the CRFs by comparing the odds ratios (ORs) per 1 SD increase in standardised predictive values. The Raman score successfully distinguished between hip fracture cases and controls. With only the score as a predictor, a statistically significant OR of 2.2 (95% confidence interval [CI]: 1.5-3.1) was found for hip fracture for up to 20 years after collection. The OR increased to 3.8 (2.6-5.4) when the CRFs were added to the model. For fractures limited to 13 years after collection, the OR was 6.3 (3.0-13.1) for the score alone. The test based on Raman spectroscopy has potential for identifying individuals who may suffer hip fractures several years in advance. Higher powered studies are required to evaluate the predictive capability of this test. PMID:29371785
Active shape modeling of the hip in the prediction of incident hip fracture.
Baker-LePain, Julie C; Luker, Kali R; Lynch, John A; Parimi, Neeta; Nevitt, Michael C; Lane, Nancy E
2011-03-01
The objective of this study was to evaluate right proximal femur shape as a risk factor for incident hip fracture using active shape modeling (ASM). A nested case-control study of white women 65 years of age and older enrolled in the Study of Osteoporotic Fractures (SOF) was performed. Subjects (n = 168) were randomly selected from study participants who experienced hip fracture during the follow-up period (mean 8.3 years). Controls (n = 231) had no fracture during follow-up. Subjects with baseline radiographic hip osteoarthritis were excluded. ASM of digitized right hip radiographs generated 10 independent modes of variation in proximal femur shape that together accounted for 95% of the variance in proximal femur shape. The association of ASM modes with incident hip fracture was analyzed by logistic regression. Together, the 10 ASM modes demonstrated good discrimination of incident hip fracture. In models controlling for age and body mass index (BMI), the area under receiver operating characteristic (AUROC) curve for hip shape was 0.813, 95% confidence interval (CI) 0.771-0.854 compared with models containing femoral neck bone mineral density (AUROC = 0.675, 95% CI 0.620-0.730), intertrochanteric bone mineral density (AUROC = 0.645, 95% CI 0.589-0.701), femoral neck length (AUROC = 0.631, 95% CI 0.573-0.690), or femoral neck width (AUROC = 0.633, 95% CI 0.574-0.691). The accuracy of fracture discrimination was improved by combining ASM modes with femoral neck bone mineral density (AUROC = 0.835, 95% CI 0.795-0.875) or with intertrochanteric bone mineral density (AUROC = 0.834, 95% CI 0.794-0.875). Hips with positive standard deviations of ASM mode 4 had the highest risk of incident hip fracture (odds ratio = 2.48, 95% CI 1.68-3.31, p < .001). We conclude that variations in the relative size of the femoral head and neck are important determinants of incident hip fracture. The addition of hip shape to fracture-prediction tools may improve the risk assessment for osteoporotic hip fractures. Copyright © 2011 American Society for Bone and Mineral Research.
Fracture risk in hepatitis C virus infected persons: results from the DANVIR cohort study.
Hansen, Ann-Brit Eg; Omland, Lars Haukali; Krarup, Henrik; Obel, Niels
2014-07-01
The association between Hepatitis C virus (HCV)-infection and fracture risk is not well characterized. We compared fracture risk between HCV-seropositive (HCV-exposed) patients and the general population and between patients with cleared and chronic HCV-infection. Outcome measures were time to first fracture at any site, time to first low-energy and first non-low-energy (other) fracture in 12,013 HCV-exposed patients from the DANVIR cohort compared with a general population control cohort (n=60,065) matched by sex and age. Within DANVIR, 4500 patients with chronic HCV-infection and 2656 patients with cleared HCV-infection were studied. Compared with population controls, HCV-exposed patients had increased overall risk of fracture [adjusted incidence rate ratio (aIRR) 2.15, 95% Confidence Interval (CI) 2.03-2.28], increased risk of low-energy fracture (aIRR 2.13, 95% CI: 1.93-2.35) and of other fracture (aIRR 2.18, 95% CI: 2.02-2.34). Compared with cleared HCV-infection, chronic HCV-infection was not associated with increased risk of fracture at any site (aIRR 1.08, 95% CI: 0.97-1.20), or other fracture (aIRR 1.04, 95% CI: 0.91-1.19). The aIRR for low-energy fracture was 1.20 (95% CI: 0.99-1.44). HCV-exposed patients had increased risk of all fracture types. In contrast, overall risk of fracture did not differ between patients with chronic vs. cleared HCV-infection, although chronic HCV-infection might be associated with a small excess risk of low-energy fractures. Our study suggests that fracture risk in HCV-infected patients is multi-factorial and mainly determined by lifestyle-related factors associated with HCV-exposure. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
Chen, Xiao; Liu, Peng; Zhu, Xiaofei; Cao, Liehu; Zhang, Chuncai; Su, Jiacan
2013-06-01
We carried out this study to test the efficacy of the olecranon memory connector (OMC) in olecranon fractures. We designed a prospective randomised controlled trial involving 40 cases of olecranon fractures. From May 2004 to December 2009, 40 patients with olecranon fractures were randomly assigned into two groups. Twenty patients were treated with OMC, while another 20 patients were fixed with locking plates in our hospital. The DASH score, MEP score, range of motion and radiographs were used to evaluate the postoperative elbow function and complications. For MEP score, OMC was better than the locking plate; for DASH score, complication rate, and range of elbow motion, the two methods presented no significant difference. The study showed that OMC could be an effective alternative to treat olecranon fractures.
Relationship between vitamin D, osteoporotic fracture and falls.
Candel Romero, Carmen; Forner Cordero, Ángeles; Sánchez Santos, José Cristóbal; Pereiró Berenguer, Inmaculada
2017-11-22
Link low levels of vitamin D, osteoporotic fracture and falls. Transversal observational study with the study variables of age, levels of vitamin D, osteoporotic fracture and falls. The study population was patients evaluated by the Rehabilitation Department, Hospital of Sagunto, from January 2013 to December 2014. Of the 242 patients who underwent vitamin D analysis, 70.6% showed levels under 30ng/ml. Forty-eight percent of the patients with below normal levels of vitamin D suffered a fracture, opposed to 32.4% patients with normal levels. Thus, controlling by age, patients with low levels of vitamin D are 4.8 times more likely to suffer a fracture than those with normal levels. Regarding falls, controlling by age, there is a higher risk of falling (adjusted OR 2.68) in those patients with low levels of vitamin D. Patients with low vitamin D levels are more likely to suffer falls and fractures. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.
Mineback Stimulation Research Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Warpinski, N.R.
The Mineback Stimulation Research Program is a systematic study of hydraulic fracturing and the parameters which influence or control fracture geometry or behavior. Fractures are created near a tunnel complex at DOE's Nevada Test Site and are monitored, instrumented, and mined back to observe the effect of treatment, rock and reservoir properties on the fractures. An initial experiment to measure width and pressure in a hydraulic fracture was completed in FY 1983. The test showed that pressure drops along fractures are much larger than predicted, with the result that fractures are shorter, higher, and wider than present models estimate. Themore » cause of this is the complex morphology of hydraulic fractures, including a hierarchy of roughnesses, multiple stranding, and corners, such as the offsets which occur when natural fractures are intersected. A test to study flow behavior in hydraulic fractures with proppant is proposed for FY 1984. 7 figures.« less
Ketamine as an Analgesic Adjuvant in Adult Trauma Intensive Care Unit Patients With Rib Fracture.
Walters, Mary K; Farhat, Joseph; Bischoff, James; Foss, Mary; Evans, Cory
2018-03-01
Rib fracture associated pain is difficult to control. There are no published studies that use ketamine as a therapeutic modality to reduce the amount of opioid to control rib fracture pain. To examine the analgesic effects of adjuvant ketamine on pain scale scores in trauma intensive care unit (ICU) rib fracture. This retrospective, case-control cohort chart review evaluated ICU adult patients with a diagnosis of ≥1 rib fracture and an Injury Severity Score >15 during 2016. Patients received standard-of-care pain management with the physician's choice analgesics with or without ketamine as a continuous, fixed, intravenous infusion at 0.1 mg/kg/h. A total of 15 ketamine treatment patients were matched with 15 control standard-of-care patients. Efficacy was measured via Numeric Pain Scale (NPS)/Behavioral Pain Scale (BPS) scores, opioid use, and ICU and hospital length of stay. Safety of ketamine was measured by changes in vital signs, adverse effects, and mortality. Average NPS/BPS, severest NPS/BPS, and opioid use were lower in the ketamine group than in controls (NPS: 4.1 vs 5.8, P < 0.001; severest NPS: 7.0 vs 8.9, P = 0.004; opioid use: 2.5 vs 3.5 mg morphine equivalents/h/d, P = 0.015). No difference was found between the cohort's length of stay or mortality. Average diastolic blood pressure was higher in the treatment group versus the control group (75.3 vs 64.6 mm Hg, P = 0.014). Low-dose ketamine appears to be a safe and effective adjuvant option to reduce pain and decrease opioid use in rib fracture.
Early mechanical stimulation only permits timely bone healing in sheep.
Tufekci, Pelin; Tavakoli, Aramesh; Dlaska, Constantin; Neumann, Mirjam; Shanker, Mihir; Saifzadeh, Siamak; Steck, Roland; Schuetz, Michael; Epari, Devakar
2018-06-01
Bone fracture healing is sensitive to the fixation stability. However, it is unclear which phases of healing are mechano-sensitive and if mechanical stimulation is required throughout repair. In this study, a novel bone defect model, which isolates an experimental fracture from functional loading, was applied in sheep to investigate if stimulation limited to the early proliferative phase is sufficient for bone healing. An active fixator controlled motion in the fracture. Animals of the control group were unstimulated. In the physiological-like group, 1 mm axial compressive movements were applied between day 5 and 21, thereafter the movements were decreased in weekly increments and stopped after 6 weeks. In the early stimulatory group, the movements were stopped after 3 weeks. The experimental fractures were evaluated with mechanical and micro-computed tomography methods after 9 weeks healing. The callus strength of the stimulated fractures (physiological-like and early stimulatory) was greater than the unstimulated control group. The control group was characterized by minimal external callus formation and a lack of bone bridging at 9 weeks. In contrast, the stimulated groups exhibited advanced healing with solid bone formation across the defect. This was confirmed quantitatively by a lower bone volume in the control group compared to the stimulated groups.The novel experimental model permits the application of a well-defined load history to an experimental bone fracture. The poor healing observed in the control group is consistent with under-stimulation. This study has shown early mechanical stimulation only is sufficient for a timely healing outcome. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1790-1796, 2018. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
Jack, Robert A; Sochacki, Kyle R; Navarro, Sergio M; McCulloch, Patrick C; Lintner, David M; Harris, Joshua D
2017-09-01
Clavicle fractures are often seen in contact sports. The purpose of this study was to determine (1) return-to-sport (RTS) rate of National Football League (NFL) players following nonoperative treatment of clavicle fractures, (2) posttreatment career length and games per season, (3) pre- and posttreatment performance, and (4) posttreatment performance compared with control players matched by position, age, years of experience, and performance. Public records were used to identify NFL players who underwent nonoperative treatment of clavicle fractures. Demographic and performance data were collected for each player. Matched controls (position, age, experience, and performance) were identified. Control and case performance scores were calculated using a standardized scoring system. Return to sport was defined as playing a minimum of 1 game after treatment. Comparisons between the 2 groups and pre- and posttreatment time points were made using paired-samples Student's t tests. Thirty players (32 fractures) were analyzed. Two players fractured their contralateral clavicle. Of the players analyzed, 96.9% were able to RTS at a mean of 244.6±119.6 days. Eight players (27.6%) returned within the same season as their injury. Overall 1-year survival rate posttreatment was 93.5%. Players with nonoperative treatment had career lengths similar to those of controls (P>.05). No significant (P>.05) differences existed in demographic, performance, or games per season data between position groups for cases and matched controls pretreatment and preindex and in posttreatment compared with pretreatment performance scores. Wide receivers played fewer games per season (P=.043) following treatment. No position group had significantly worse posttreatment performance scores when compared with postindex matched controls. [Orthopedics. 2017; 40(5):e836-e843.]. Copyright 2017, SLACK Incorporated.
Magnus, Charlene R A; Arnold, Cathy M; Johnston, Geoffrey; Dal-Bello Haas, Vanina; Basran, Jenny; Krentz, Joel R; Farthing, Jonathan P
2013-07-01
To evaluate the effects of cross-education (contralateral effect of unilateral strength training) during recovery from unilateral distal radius fractures on muscle strength, range of motion (ROM), and function. Randomized controlled trial (26-wk follow-up). Hospital, orthopedic fracture clinic. Women older than 50 years with a unilateral distal radius fracture. Fifty-one participants were randomized and 39 participants were included in the final data analysis. Participants were randomized to standard rehabilitation (Control) or standard rehabilitation plus strength training (Train). Standard rehabilitation included forearm casting for 40.4±6.2 days and hand exercises for the fractured extremity. Nonfractured hand strength training for the training group began immediately postfracture and was conducted at home 3 times/week for 26 weeks. The primary outcome measure was peak force (handgrip dynamometer). Secondary outcomes were ROM (flexion/extension; supination/pronation) via goniometer and the Patient Rated Wrist Evaluation questionnaire score for the fractured arm. For the fractured hand, the training group (17.3±7.4kg) was significantly stronger than the control group (11.8±5.8kg) at 12 weeks postfracture (P<.017). There were no significant strength differences between the training and control groups at 9 (12.5±8.2kg; 11.3±6.9kg) or 26 weeks (23.0±7.6kg; 19.6±5.5kg) postfracture, respectively. Fractured hand ROM showed that the training group had significantly improved wrist flexion/extension (100.5°±19.2°) than the control group (80.2°±18.7°) at 12 weeks postfracture (P<.017). There were no significant differences between the training and control groups for flexion/extension ROM at 9 (78.0°±20.7°; 81.7°±25.7°) or 26 weeks (104.4°±15.5°; 106.0°±26.5°) or supination/pronation ROM at 9 (153.9°±23.9°; 151.8°±33.0°), 12 (170.9°±9.3°; 156.7°±20.8°) or 26 weeks (169.4°±11.9°; 162.8°±18.1°), respectively. There were no significant differences in Patient Rated Wrist Evaluation questionnaire scores between the training and control groups at 9 (54.2±39.0; 65.2±28.9), 12 (36.4±37.2; 46.2±35.3), or 26 weeks (23.6±25.6; 19.4±16.5), respectively. Strength training for the nonfractured limb after a distal radius fracture was associated with improved strength and ROM in the fractured limb at 12 weeks postfracture. These results have important implications for rehabilitation strategies after unilateral injuries. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Steroidal contraceptives and bone fractures in women: evidence from observational studies.
Lopez, Laureen M; Chen, Mario; Mullins Long, Sarah; Curtis, Kathryn M; Helmerhorst, Frans M
2015-07-21
Age-related decline in bone mass increases the risk of skeletal fractures, especially those of the hip, spine, and wrist. Steroidal contraceptives have been associated with changes in bone mineral density in women. Whether such changes affect the risk of fractures later in life is unclear. Hormonal contraceptives are among the most effective and most widely-used contraceptives. Concern about fractures may limit the use of these effective contraceptives. Observational studies can collect data on premenopausal contraceptive use as well as fracture incidence later in life. We systematically reviewed the evidence from observational studies of hormonal contraceptive use for contraception and the risk of fracture in women. Through June 2015, we searched for observational studies. The databases included PubMed, POPLINE, Cochrane Central Register of Controlled Trials (CENTRAL), LILACS, EMBASE, CINAHL, and Web of Science. We also searched for recent clinical trials through ClinicalTrials.gov and the ICTRP. For other studies, we examined reference lists of relevant articles and wrote to investigators for additional reports. We included cohort and case-control studies of hormonal contraceptive use. Interventions included comparisons of a hormonal contraceptive with a non-hormonal contraceptive, no contraceptive, or another hormonal contraceptive. The primary outcome was the risk of fracture. Two authors independently extracted the data. One author entered the data into RevMan, and a second author verified accuracy. We examined the quality of evidence using the Newcastle-Ottawa Quality Assessment Scale (NOS), developed for case-control and cohort studies. Sensitivity analysis included studies of moderate or high quality based on our assessment with the NOS.Given the need to control for confounding factors in observational studies, we used adjusted estimates from the models as reported by the authors. Where we did not have adjusted analyses, we calculated the odds ratio (OR) with 95% confidence interval (CI). Due to varied study designs, we did not conduct meta-analysis. We included 14 studies (7 case-control and 7 cohort studies). These examined oral contraceptives (OCs), depot medroxyprogesterone acetate (DMPA), and the hormonal intrauterine device (IUD). This section focuses on the sensitivity analysis with six studies that provided moderate or high quality evidence.All six studies examined oral contraceptive use. We noted few associations with fracture risk. One cohort study reported OC ever-users had increased risk for all fractures (RR 1.20, 95% CI 1.08 to 1.34). However, a case-control study with later data from a subset reported no association except for those with 10 years or more since use (OR 1.55, 95% CI 1.03 to 2.33). Another case-control study reported increased risk only for those who had 10 or more prescriptions (OR 1.09, 95% CI 1.03 to 1.16). A cohort study of postmenopausal women found no increased fracture risk for OC use after excluding women with prior fracture. Two other studies found little evidence of association between OC use and fracture risk. A cohort study noted increased risk for subgroups, such as those with longer use or specific intervals since use. A case-control study reported increased risk for any fracture only among young women with less than average use.Two case-control studies also examined progestin-only contraceptives. One reported increased fracture risk for DMPA ever-use (OR 1.44, 95% CI 1.01 to 2.06), more than four years of use (OR 2.16, 95% CI 1.32 to 3.53), and women over 50 years old. The other reported increased risk for any past use, including one or two prescriptions (OR 1.17, 95% CI 1.07 to 1.29) and for current use of 3 to 9 prescriptions (OR 1.36, 95% CI 1.15 to 1.60) or 10 or more (OR 1.54, 95% CI 1.33 to 1.78). For the levonorgestrel-releasing IUD, one study reported reduced fracture risk for ever-use (OR 0.75, 95% CI 0.64 to 0.87) and for longer use. Observational studies do not indicate an overall association between oral contraceptive use and fracture risk. Some reported increased risk for specific user subgroups. DMPA users may have an increased fracture risk. One study indicated hormonal IUD use may be associated with decreased risk. Observational studies need adjusted analysis because the comparison groups usually differ. Investigators should be clear about the variables examined in multivariate analysis.
Rib Fracture Diagnosis in the Panscan Era.
Murphy, Charles E; Raja, Ali S; Baumann, Brigitte M; Medak, Anthony J; Langdorf, Mark I; Nishijima, Daniel K; Hendey, Gregory W; Mower, William R; Rodriguez, Robert M
2017-12-01
With increased use of chest computed tomography (CT) in trauma evaluation, traditional teachings in regard to rib fracture morbidity and mortality may no longer be accurate. We seek to determine rates of rib fracture observed on chest CT only; admission and mortality of patients with isolated rib fractures, rib fractures observed on CT only, and first or second rib fractures; and first or second rib fracture-associated great vessel injury. We conducted a planned secondary analysis of 2 prospectively enrolled cohorts of the National Emergency X-Radiography Utilization Study chest studies, which evaluated patients with blunt trauma who were older than 14 years and received chest imaging in the emergency department. We defined rib fractures and other thoracic injuries according to CT reports and followed patients through their hospital course to determine outcomes. Of 8,661 patients who had both chest radiograph and chest CT, 2,071 (23.9%) had rib fractures, and rib fractures were observed on chest CT only in 1,368 cases (66.1%). Rib fracture patients had higher admission rates (88.7% versus 45.8%; mean difference 42.9%; 95% confidence interval [CI] 41.4% to 44.4%) and mortality (5.6% versus 2.7%; mean difference 2.9%; 95% CI 1.8% to 4.0%) than patients without rib fracture. The mortality of patients with rib fracture observed on chest CT only was not statistically significantly different from that of patients with fractures also observed on chest radiograph (4.8% versus 5.7%; mean difference -0.9%; 95% CI -3.1% to 1.1%). Patients with first or second rib fractures had significantly higher mortality (7.4% versus 4.1%; mean difference 3.3%; 95% CI 0.2% to 7.1%) and prevalence of concomitant great vessel injury (2.8% versus 0.6%; mean difference 2.2%; 95% CI 0.6% to 4.9%) than patients with fractures of ribs 3 to 12, and the odds ratio of great vessel injury with first or second rib fracture was 4.4 (95% CI 1.8 to 10.4). Under trauma imaging protocols that commonly incorporate chest CT, two thirds of rib fractures were observed on chest CT only. Patients with rib fractures had higher admission rates and mortality than those without rib fractures. First or second rib fractures were associated with significantly higher mortality and great vessel injury. Copyright © 2017 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
Iwamoto, Jun; Matsumoto, Hideo; Takeda, Tsuyoshi
2009-01-01
Patients with neurological diseases such as Alzheimer's disease, stroke and Parkinson's disease have been reported to have vitamin K deficiency secondary to malnutrition, which increases the risk of non-vertebral and hip fractures. The purpose of the present study was to clarify the efficacy of menatetrenone (vitamin K(2)) against non-vertebral and hip fractures in patients with neurological diseases. A literature search was conducted on PubMed from January 1995 to July 2008 to identify randomized controlled trials (RCTs) of use of menatetrenone against non-vertebral and hip fractures in patients with neurological diseases. A meta-analysis of all RCTs meeting these criteria was then performed. Three RCTs of patients with Alzheimer's disease (n = 178, mean age 78 years), stroke (n = 99, mean age 66 years) and Parkinson's disease (n = 110, mean age 72 years) met the criteria for meta-analysis. These RCTs did not include placebo controls but did have non-treatment controls. According to the meta-analysis, the overall relative risks (95% confidence intervals) for non-vertebral and hip fractures with menatetrenone treatment compared with non-treatment were 0.13 (0.05, 0.35) and 0.14 (0.05, 0.43), respectively, in patients with neurological diseases. No severe adverse events were reported with menatetrenone treatment. The present meta-analysis of three RCTs suggests that there is efficacy for menatetrenone treatment against non-vertebral and hip fractures among patients with neurological diseases. Further larger placebo-controlled trials are needed to confirm the results of the present study.
NASA Astrophysics Data System (ADS)
Zhong, L.; Wu, X.; Dai, C.
2017-12-01
Over the past decade, the rapid rise of unconventional shale gas and tight sandstone oil development through horizontal drilling and high volume hydraulic fracturing has expanded the extraction of hydrocarbon resources. Hydraulic fracturing fluids play very important roles in enhanced oil/gas recovery. However, damage to the reservoir rock and environmental contamination caused by hydraulic fracturing flowback fluids has raised serious concerns. The development of reservoir rock friendly and environmental benign fracturing fluids is in immediate demand. Studies to improve properties of hydraulic fracturing fluids have found that viscoelastic surfactant (VES) fracturing fluid can increase the productivity of gas/oil and be efficiently extracted after fracturing. Compared to conventional polymer fracturing fluid, VES fracturing fluid has many advantages, such as few components, easy preparation, good proppant transport capacity, low damage to cracks and formations, and environment friendly. In this work, we are developing a novel CO2-responsive VES fracking fluid that can readily be reused. This fluid has a gelling-breaking process that can be easily controlled by the presence of CO2 and its pressure. We synthesized erucamidopropyl dimethylamine (EA) as a thickening agent for hydraulic fracturing fluid. The influence of temperature, presence of CO2 and pressure on the viscoelastic behavior of this fluid was then investigated through rheological measurements. The fracturing fluid performance and recycle property were lastly studied using core flooding tests. We expect this fluid finds applications not only in enhanced oil/gas recovery, but also in areas such as controlling groundwater pollution and microfluidics.
Mitov, Gergo; Anastassova-Yoshida, Yana; Nothdurft, Frank Phillip; von See, Constantin; Pospiech, Peter
2016-02-01
The aim of this study was to evaluate the fracture resistance and fracture behavior of monolithic zirconia crowns in accordance with the preparation design and aging simulation method. An upper first molar was prepared sequentially with three different preparation designs: shoulderless preparation, 0.4 mm chamfer and 0.8 mm chamfer preparation. For each preparation design, 30 monolithic zirconia crowns were fabricated. After cementation on Cr-Co alloy dies, the following artificial aging procedures were performed: (1) thermal cycling and mechanical loading (TCML): 5000 cycles of thermal cycling 5℃-55℃ and chewing simulation (1,200,000 cycles, 50 N); (2) Low Temperature Degradation simulation (LTD): autoclave treatment at 137℃, 2 bar for 3 hours and chewing simulation; and (3) no pre-treatment (control group). After artificial aging, the crowns were loaded until fracture. The mean values of fracture resistance varied between 3414 N (LTD; 0.8 mm chamfer preparation) and 5712 N (control group; shoulderless preparation). Two-way ANOVA analysis showed a significantly higher fracture loads for the shoulderless preparation, whereas no difference was found between the chamfer preparations. In contrast to TCML, after LTD simulation the fracture strength of monolithic zirconia crowns decreased significantly. The monolithic crowns tested in this study showed generally high fracture load values. Preparation design and LTD simulation had a significant influence on the fracture strength of monolithic zirconia crowns.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hoak, T.E.; Klawitter, A.L.
Fractured production trends in Piceance Basin Cretaceous-age Mesaverde Group gas reservoirs are controlled by subsurface structures. Because many of the subsurface structures are controlled by basement fault trends, a new interpretation of basement structure was performed using an integrated interpretation of Landsat Thematic Mapper (TM), side-looking airborne radar (SLAR), high altitude, false color aerial photography, gas and water production data, high-resolution aeromagnetic data, subsurface geologic information, and surficial fracture maps. This new interpretation demonstrates the importance of basement structures on the nucleation and development of overlying structures and associated natural fractures in the hydrocarbon-bearing section. Grand Valley, Parachute, Rulison, Plateau,more » Shire Gulch, White River Dome, Divide Creek and Wolf Creek fields all produce gas from fractured tight gas sand and coal reservoirs within the Mesaverde Group. Tectonic fracturing involving basement structures is responsible for development of permeability allowing economic production from the reservoirs. In this context, the significance of detecting natural fractures using the intergrated fracture detection technique is critical to developing tight gas resources. Integration of data from widely-available, relatively inexpensive sources such as high-resolution aeromagnetics, remote sensing imagery analysis and regional geologic syntheses provide diagnostic data sets to incorporate into an overall methodology for targeting fractured reservoirs. The ultimate application of this methodology is the development and calibration of a potent exploration tool to predict subsurface fractured reservoirs, and target areas for exploration drilling, and infill and step-out development programs.« less
Effects of water saturation on P-wave propagation in fractured coals: An experimental perspective
NASA Astrophysics Data System (ADS)
Liu, Jie; Liu, Dameng; Cai, Yidong; Gan, Quan; Yao, Yanbin
2017-09-01
Internal structure of coalbed methane (CBM) reservoirs can be evaluated through ultrasonic measurements. The compressional wave that propagates in a fractured coal reservoir may indicate the internal coal structure and fluid characteristics. The P-wave propagation was proposed to study the relations between petrophysical parameters (including water saturation, fractures, porosity and permeability) of coals and the P-wave velocity (Vp), using a KON-NM-4A ultrasonic velocity meter. In this study, the relations between Vps and water saturations were established: Type I is mainly controlled by capillary of developed seepage pores. The controlling factors on Type II and Type III are internal homogeneity of pores/fractures and developed micro-fractures, respectively. Micro-fractures density linearly correlates with the Vp due to the fracture volume and dispersion of P-wave; and micro-fractures of types C and D have a priority in Vp. For dry coals, no clear relation exists between porosity, permeability and the Vp. However, as for water-saturated coals, the correlation coefficients of porosity, permeability and Vp are slightly improved. The Vp of saturated coals could be predicted with the equation of Vp-saturated = 1.4952Vp-dry-26.742 m/s. The relation between petrophysical parameters of coals and Vp under various water saturations can be used to evaluate the internal structure in fractured coals. Therefore, these relations have significant implications for coalbed methane (CBM) exploration.
Hip fractures in the elderly in Israel-possible impact of preventable conditions.
Segal, Elena; Raichlin, Valentina; Rimbrot, Sophia; Zinman, Chaim; Raz, Batia; Ish-Shalom, Sophia
2009-01-01
In the present study we evaluated the possible contribution of different factors to the occurrence of hip fractures in Israel. We assessed medical history, physical activity, body mass index, smoking status, bone turnover markers and calcium regulating hormones levels of 142 consecutive elderly hip fracture patients (HFP), and compared them to 96 community dwelling elderly people without a history of hip fracture. Age and female gender were the strongest predictors of hip fracture, p<0.001 and 0.013. Stepwise logistic regression demonstrated that HFP had higher PTH and lower 25(OH)D(3) levels, p=0.002, p<0.001; they were less physically active, p<0.001, and had higher rate of vitamin D insufficiency during winter-spring, compared to summer-autumn, p=0.033. Diabetics had higher risk for hip fracture, p=0.06, OR=3.9 (95% CI 1.50-10.4). Deoxypyridinoline (DPD) cross links levels were 19.35+/-10.58mg/mg creatinine in HFP and 9.12+/-3.52 in controls, p<0.0001. Bone alkaline phosphatase (BAP)/DPD ratio was 1.5 in controls compared to 0.53 in HFP. We conclude that age and female gender were the strongest predictors for hip fracture. Diabetic patients had threefold risk for hip fracture. Bone formation/bone resorption ratio was lower in HFP. Vitamin D deficiency and physical inactivity are important preventable risk factors for hip fracture.
Tamiya, Hiroyuki; Yasunaga, Hideo; Matusi, Hiroki; Fushimi, Kiyohide; Ogawa, Sumito; Akishita, Masahiro
2015-01-01
Preventing falls and bone fractures in hospital care is an important issue in geriatric medicine. Use of hypnotics is a potential risk factor for falls and bone fractures in older patients. However, data are lacking on the association between use of hypnotics and the occurrence of bone fracture. We used a national inpatient database including 1,057 hospitals in Japan and included dementia patients aged 50 years or older who were hospitalized during a period of 12 months between April 2012 and March 2013. The primary outcome was the occurrence of bone fracture during hospitalization. Use of hypnotics was compared between patients with and without bone fracture in this matched case-control study. Of 140,494 patients, 830 patients suffered from in-hospital fracture. A 1:4 matching with age, sex and hospital created 817 cases with fracture and 3,158 matched patients without fracture. With adjustment for the Charlson comorbidity index, emergent admission, activities of daily living, and scores for level walking, a higher occurrence of fractures were seen with short-acting benzodiazepine hypnotics (odds ratio, 1.43; 95% confidence interval, 1.19-1.73; P<0.001), ultrashort-acting non-benzodiazepine hypnotics (1.66; 1.37-2.01; P<0.001), hydroxyzine (1.45; 1.15-1.82, P=0.001), risperidone and perospirone (1.37; 1.08-1.73; P=0.010). Other drug groups were not significantly associated with the occurrence of in-hospital fracture. Short-acting benzodiazepine hypnotics and ultrashort-acting non-benzodiazepine hypnotics may increase risk of bone fracture in hospitalized dementia patients.
Evaluation of hip fracture risk factors in older adults in the Lebanese population.
Bawab, Wafa; Saad, Mohamad; Hajjar, Nour; Rachidi, Samar; Al Hajje, Amal; Awada, Sanaa; Salameh, Pascale
2014-01-01
Hip fractures are serious fall injuries that often result in long-term functional impairment and increased mortality. As the population ages, the number of hip fractures is likely to increase worldwide. The main objective of this pilot study was to evaluate the risk factors of hip fracture among the older adults in the Lebanese population. This pilot epidemiological, prospective, and case-control study was performed in 6 hospitals in Great Beirut and South Lebanon. Subjects who met the inclusion criteria filled out a questionnaire consisting on the socio- demographic characteristics, health status, drugs intake and cigarette smoking. Overall, 195 subjects were recruited, with 65 cases of hip fracture and 130 controls all aged over 50 yr. Females represented around two third of the studied population. The logistic regression, using adjusted odds ratio (ORa), showed a significant relationship between hip fracture and chronic diseases (ORa=3.02; 95% CI: 1.63, 6.66), antihypertensive drugs intake (ORa=2.72; 95% CI: 1.56, 6.42), fall (ORa=2.79; 95% CI: 1.82, 7.06) previous fracture (ORa=3.80; 95% CI: 1.57, 9.23) and family history of fracture (ORa=4.82; 95% CI: (2.29, 10.86). Besides, smoking increased the risk of hip fracture (ORa=2.55; 95% CI: (1.96, 5.80). Having a bow was associated with the highest risk for hip fracture (ORa=5.18; 95% CI: 2.30, 12.24). Elderly people in Lebanon are exposed to many risk factors contributing to hip fracture. Our finding has implication in geriatric health improvement by preventing hip fracture in the Lebanese population.
NASA Astrophysics Data System (ADS)
Zorn, Erich Victor
In 2012 and 2013, hydraulic fracturing was performed at two Marcellus Shale well pads, under the supervision of the Energy Corporation of America. Six lateral wells were hydraulically fractured in Greene County in southwestern Pennsylvania and one lateral well was fractured in Clearfield County in north-central Pennsylvania. During hydraulic fracturing operations, microseismic monitoring by strings of downhole geophones detected a combination of >16,000 microseismic events at the two sites. High quality traditional and geomechanical well logs were acquired at Clearfield County, as well as tomographic velocity profiles before and after stimulation. In partnership with the US Department of Energy's National Energy Technology Laboratory, I completed detailed analysis of these geophysical datasets to maximize the understanding of the engineering and geological conditions in the reservoir, the connection between hydraulic input and microseismic expression, and the geomechanical factors that control microseismic properties. Additionally, one broad-band surface seismometer was deployed at Greene County and left to passively monitor site acoustics for the duration of hydraulic fracturing. Data from this instrument shows the presence of slow-slip or long period/long duration (LPLD) seismicity. In years prior to our investigation, lab-scale fracturing studies and broadband seismic monitoring of hydraulic fracturing had been completed by other researchers in unconventional shale and tight sand in Texas and Canada. This is the first study of LPLD seismicity in the Marcellus Shale and reveals aseismic deformation during hydraulic fracturing that could account for a large portion of "lost" hydraulic energy input. Key accomplishments of the studies contained in this dissertation include interpreting microseismic data in terms of hydraulic pumping data and vice versa, verifying the presence of LPLD seismicity during fracturing, establishing important geomechanical controls on the character of induced microseismicity, and extensive data integration toward locating a previously unmapped fault that appears to have exhibited significant control over well stimulation efforts at Clearfield.
Multi-scale nitrate transport in a sandstone aquifer system under intensive agriculture
NASA Astrophysics Data System (ADS)
Paradis, Daniel; Ballard, Jean-Marc; Lefebvre, René; Savard, Martine M.
2018-03-01
Nitrate transport in heterogeneous bedrock aquifers is influenced by mechanisms that operate at different spatial and temporal scales. To understand these mechanisms in a fractured sandstone aquifer with high porosity, a groundwater-flow and nitrate transport model—reproducing multiple hydraulic and chemical targets—was developed to explain the actual nitrate contamination observed in groundwater and surface water in a study area on Prince Edward Island, Canada. Simulations show that nitrate is leached to the aquifer year-round, with 61% coming from untransformed and transformed organic sources originating from fertilizers and manure. This nitrate reaches the more permeable shallow aquifer through fractures in weathered sandstone that represent only 1% of the total porosity (17%). Some of the nitrate reaches the underlying aquifer, which is less active in terms of groundwater flow, but most of it is drained to the main river. The river-water quality is controlled by the nitrate input from the shallow aquifer. Groundwater in the underlying aquifer, which has long residence times, is also largely influenced by the diffusion of nitrate in the porous sandstone matrix. Consequently, following a change of fertilizer application practices, water quality in domestic wells and the river would change rapidly due to the level of nitrate found in fractures, but a lag time of up to 20 years would be necessary to reach a steady level due to diffusion. This demonstrates the importance of understanding nitrate transport mechanisms when designing effective agricultural and water management plans to improve water quality.
Kampe, Karin; Kohler, Michaela; Albrecht, Diana; Becker, Clemens; Hautzinger, Martin; Lindemann, Ulrich; Pfeiffer, Klaus
2017-05-01
Based on a theoretical framework and sound evidence, this article describes a rehabilitation programme for patients with fear of falling after hip and pelvic fracture. Based on exercise science principles, current knowledge from fall prevention, emotion regulation, and the Health Action Process Approach we developed a theoretical framework, from which the components of the intervention were derived. Description of the intervention: The intervention consists of 6 components: (1) relaxation, (2) meaningful activities and mobility-based goals, (3) falls related cognitions and emotions, coping with high risk tasks and situations, (4) individual exercise programme, (5) planning and implementing exercises and activities, and (6) fall risks and hazards. The intervention comprises of 8 individual sessions during 3 to 5 weeks of inpatient rehabilitation and 4 telephone calls and 1 home visit over a 2-month post-discharge period. Each session or telephone call takes about 30-60 minutes. It is provided to geriatric hip and pelvic fracture patients with concerns about falling and no cognitive impairment. To ensure completeness of reporting, the Template for Intervention Description and Replication (TIDierR) is used. Fifty-seven patients were assigned to the intervention group. All 46 completers met all pre-defined criteria for an intervention per protocol. The programme is feasible to administer. We have completed a randomised controlled trial, which will be submitted in due time (for trial protocol: www.isrctn.org ; ISRCTN79191813).
Gout and the Risk of Non-vertebral Fracture
Kim, Seoyoung C.; Paik, Julie M.; Liu, Jun; Curhan, Gary C.; Solomon, Daniel H.
2016-01-01
Prior studies suggest an association between osteoporosis, systemic inflammation and pro-inflammatory cytokines such as IL-1 and IL-6. Conflicting findings exist on the association between hyperuricemia and osteoporosis. Furthermore, it remains unknown whether gout, a common inflammatory arthritis, affects fracture risk. Using data from a US commercial health plan (2004–2013), we evaluated the risk of non-vertebral fracture (i.e. forearm, wrist, hip and pelvis) in patients with gout versus those without. Gout patients were identified with ≥2 diagnosis codes and ≥1 dispensing for a gout-related drug. Non-gout patients, identified with ≥2 visits coded for any diagnosis and ≥1 dispensing for any prescription drugs, were free of gout diagnosis and received no gout-related drugs. Hip fracture was the secondary outcome. Fractures were identified with a combination of diagnosis and procedure codes. Cox proportional hazards models compared the risk of non-vertebral fracture in gout patients versus non-gout, adjusting for over 40 risk factors for osteoporotic fracture. Among gout patients with baseline serum uric acid (sUA) measurements available, we assessed the risk of non-vertebral fracture associated with sUA. We identified 73,202 gout and 219,606 non-gout patients, matched on age, sex, and the date of study entry. The mean age was 60 years and 82% were men. Over the mean 2-year follow-up, the incidence rate of non-vertebral fracture per 1,000 person-years was 2.92 in gout and 2.66 in non-gout. The adjusted hazard ratio (HR) was 0.98 (95%CI 0.85–1.12) for non-vertebral fracture and 0.83 (95%CI 0.65–1.07) for hip fracture in gout versus non-gout. Subgroup analysis (n=15,079) showed no association between baseline sUA and non-vertebral fracture (HR 1.03, 95%CI 0.93–1.15), adjusted for age, sex, comorbidity score and number of any prescription drugs. Gout was not associated with a risk of non-vertebral fracture. Among patients with gout, sUA was not associated with the risk of non-vertebral fracture. PMID:27541696
[Isolated hyoid bone fracture due to blunt trauma: case report].
Erdoğan, Mehmet Ozgür; Koşargelir, Mehmet; Yorulmaz, Rasim; Meriç, Kaan; Erdoğan, Barış
2013-05-01
Fractures of the hyoid bone are very rare. Diagnosis of hyoid fracture is difficult and can be made only with a strong degree of suspicion. We report a case of isolated hyoid bone fracture due to blunt trauma to the neck. A 26-year-old woman was admitted to emergency department for motor vehicle accident. She complained of dysphagia and anterior neck discomfort. Physical examination showed hyperemia and tenderness of neck. A tomographic scan of neck was performed. The findings demonstrated hyoid fracture. Patient was observed with medical therapy for 24 hours and discharged with recommendation of outpatient control.Emergency physician has to be aware of the possibility of hyoid fractures in blunt traumas. Patients with hyoid fracture should be observed for 24 hours. Generally, medical treatment is satisfactory in isolated hyoid fractures.
Structural controls on anomalous transport in fractured porous rock
NASA Astrophysics Data System (ADS)
Edery, Yaniv; Geiger, Sebastian; Berkowitz, Brian
2016-07-01
Anomalous transport is ubiquitous in a wide range of disordered systems, notably in fractured porous formations. We quantitatively identify the structural controls on anomalous tracer transport in a model of a real fractured geological formation that was mapped in an outcrop. The transport, determined by a continuum scale mathematical model, is characterized by breakthrough curves (BTCs) that document anomalous (or "non-Fickian") transport, which is accounted for by a power law distribution of local transition times ψ>(t>) within the framework of a continuous time random walk (CTRW). We show that the determination of ψ>(t>) is related to fractures aligned approximately with the macroscopic direction of flow. We establish the dominant role of fracture alignment and assess the statistics of these fractures by determining a concentration-visitation weighted residence time histogram. We then convert the histogram to a probability density function (pdf) that coincides with the CTRW ψ>(t>) and hence anomalous transport. We show that the permeability of the geological formation hosting the fracture network has a limited effect on the anomalous nature of the transport; rather, it is the fractures transverse to the flow direction that play the major role in forming the long BTC tail associated with anomalous transport. This is a remarkable result, given the complexity of the flow field statistics as captured by concentration transitions.
Fracture identification based on remote detection acoustic reflection logging
NASA Astrophysics Data System (ADS)
Zhang, Gong; Li, Ning; Guo, Hong-Wei; Wu, Hong-Liang; Luo, Chao
2015-12-01
Fracture identification is important for the evaluation of carbonate reservoirs. However, conventional logging equipment has small depth of investigation and cannot detect rock fractures more than three meters away from the borehole. Remote acoustic logging uses phase-controlled array-transmitting and long sound probes that increase the depth of investigation. The interpretation of logging data with respect to fractures is typically guided by practical experience rather than theory and is often ambiguous. We use remote acoustic reflection logging data and high-order finite-difference approximations in the forward modeling and prestack reverse-time migration to image fractures. First, we perform forward modeling of the fracture responses as a function of the fracture-borehole wall distance, aperture, and dip angle. Second, we extract the energy intensity within the imaging area to determine whether the fracture can be identified as the formation velocity is varied. Finally, we evaluate the effect of the fracture-borehole distance, fracture aperture, and dip angle on fracture identification.
Preferential pathways in complex fracture systems and their influence on large scale transport
NASA Astrophysics Data System (ADS)
Willmann, M.; Mañé, R.; Tyukhova, A.
2017-12-01
Many subsurface applications in complex fracture systems require large-scale predictions. Precise predictions are difficult because of the existence of preferential pathways at different scales. The intrinsic complexity of fracture systems increases within fractured sedimentary formations, because also the coupling of fractures and matrix has to be taken into account. This interplay of fracture system and the sedimentary matrix is strongly controlled by the actual fracture aperture of an individual fracture. And an effective aperture cannot be easily be determined because of the preferential pathways along the fracture plane. We investigate the influence of these preferential pathways on large scale solute transport and upscale the aperture. By explicitly modeling flow and particle tracking in individual fractures, we develop a new effective transport aperture, which is weighted by the aperture along the preferential paths, a Lagrangian aperture. We show that this new aperture is consistently larger than existing definitions of effective flow and transport apertures. Finally, we apply our results to a fractured sedimentary formation in Northern Switzerland.
High-resolution cross-borehole thermal tracer testing in granite: preliminary field results
NASA Astrophysics Data System (ADS)
Brixel, Bernard; Klepikova, Maria; Jalali, Mohammadreza; Amann, Florian; Loew, Simon
2017-04-01
Understanding how heat is transported, stored and exchanged across fractured media is becoming increasingly relevant in our society, as manifested from the growing popularity of modern technologies relying on the subsurface to either source or store heat. One good example is the utilization of heat from deep hydrothermal or petrothermal systems to generate electricity for base load power generation, a technology also known as deep geothermal energy (DGE). While very attractive in principle, the number of geothermal fields producing economical levels of electricity to this day is still very limited - largely due to the difficulty of either locating deep reservoirs that are both sufficiently hot and permeable or, in the absence of the latter, creating them. In this context, the Swiss Competence Center for Energy Research - Supply of Electricity (SCCER - SoE) is carrying out an in situ stimulation and circulation (ISC) experiment at the Grimsel Test Site (GTS), an underground rock lab located in the Aar massif, in the Swiss Alps. The circulation experiment planned for the post-stimulation phase represents one of the key components of this experimental research program, and the outcome of this test is expected to ultimately provide key insights in the factors controlling the performance of enhanced geothermal reservoirs. Therefore, to support the design of this experiment, short-term thermal tracer tests (TTT) were conducted with the objective to (i) assess the feasibility of conducting TTTs in a relatively intact granite (where fluid flow is controlled by a limited number of discrete fractures); (ii) determine optimal experimental setups; and to ultimately (iii) monitor thermal breakthroughs at high spatial and temporal resolution, providing insights on heat transport and complementing the characterization of hydrogeological conditions carried out through conventional means (e.g. hydraulic and/or solute tracer tests). Presented herein are the results of a 10-day thermal tracer test conducted by continuously injecting water at 40°C (ambient groundwater temperatures average around 12-13 °C) across a discrete fractured zone, isolated with packers. Monitoring was achieved using a combination of discrete temperature sensors (PT1000) and FO DTS (Silixa XT system) deployed along a network of both packed-off and open boreholes situated approx. 6-20 m apart from the injection zone. Thermal breakthrough was observed in multiple boreholes, as early as 6-7 hours following the injection of hot water. The rate of increase in temperatures was observed to significantly diminish over time, allowing water in the fracture carrying the majority of heat to reach a temperature of 17°C at the closest observation location. Furthermore, temperature declined along the fracture length. These data allowed us identifying the precise location of conductive fractures, thereby improving our understanding of the connectivity structure of our experimental rock volume. In addition, these results provide significant insights on heat transport and the efficiency of heat-exchange between fractures and the surrounding rock mass at Grimsel.
Hannemann, Pascal; Göttgens, Kevin W A; van Wely, Bob J; Kolkman, Karel A; Werre, Andries J; Poeze, Martijn; Brink, Peter R G
2011-05-06
The scaphoid bone is the most commonly fractured of the carpal bones. In the Netherlands 90% of all carpal fractures is a fracture of the scaphoid bone. The scaphoid has an essential role in functionality of the wrist, acting as a pivot. Complications in healing can result in poor functional outcome. The scaphoid fracture is a troublesome fracture and failure of treatment can result in avascular necrosis (up to 40%), non-union (5-21%) and early osteo-arthritis (up to 32%) which may seriously impair wrist function. Impaired consolidation of scaphoid fractures results in longer immobilization and more days lost at work with significant psychosocial and financial consequences.Initially Pulsed Electromagnetic Fields was used in the treatment of tibial pseudoarthrosis and non-union. More recently there is evidence that physical forces can also be used in the treatment of fresh fractures, showing accelerated healing by 30% and 71% reduction in nonunion within 12 weeks after initiation of therapy. Until now no double blind randomized, placebo controlled trial has been conducted to investigate the effect of this treatment on the healing of fresh fractures of the scaphoid. This is a multi center, prospective, double blind, placebo controlled, randomized trial. Study population consists of all patients with unilateral acute scaphoid fracture. Pregnant women, patients having a life supporting implanted electronic device, patients with additional fractures of wrist, carpal or metacarpal bones and pre-existing impairment in wrist function are excluded. The scaphoid fracture is diagnosed by a combination of physical and radiographic examination (CT-scanning).Proven scaphoid fractures are treated with cast immobilization and a small Pulsed Electromagnetic Fields bone growth stimulating device placed on the cast. Half of the devices will be disabled at random in the factory.Study parameters are clinical consolidation, radiological consolidation evaluated by CT-scanning, functional status of the wrist, including assessment by means of the patient rated wrist evaluation (PRWE) questionnaire and quality of life using SF-36 health survey questionnaire.Primary endpoint is number of scaphoid unions at six weeks, secondary endpoints are time interval to clinical and radiological consolidation, number of non-unions, functional status at 52 weeks and non-adherence to the treatment protocol. Netherlands Trial Register (NTR): NTR2064. © 2011 Hannemann et al; licensee BioMed Central Ltd.
2011-01-01
Background The scaphoid bone is the most commonly fractured of the carpal bones. In the Netherlands 90% of all carpal fractures is a fracture of the scaphoid bone. The scaphoid has an essential role in functionality of the wrist, acting as a pivot. Complications in healing can result in poor functional outcome. The scaphoid fracture is a troublesome fracture and failure of treatment can result in avascular necrosis (up to 40%), non-union (5-21%) and early osteo-arthritis (up to 32%) which may seriously impair wrist function. Impaired consolidation of scaphoid fractures results in longer immobilization and more days lost at work with significant psychosocial and financial consequences. Initially Pulsed Electromagnetic Fields was used in the treatment of tibial pseudoarthrosis and non-union. More recently there is evidence that physical forces can also be used in the treatment of fresh fractures, showing accelerated healing by 30% and 71% reduction in nonunion within 12 weeks after initiation of therapy. Until now no double blind randomized, placebo controlled trial has been conducted to investigate the effect of this treatment on the healing of fresh fractures of the scaphoid. Methods/Design This is a multi center, prospective, double blind, placebo controlled, randomized trial. Study population consists of all patients with unilateral acute scaphoid fracture. Pregnant women, patients having a life supporting implanted electronic device, patients with additional fractures of wrist, carpal or metacarpal bones and pre-existing impairment in wrist function are excluded. The scaphoid fracture is diagnosed by a combination of physical and radiographic examination (CT-scanning). Proven scaphoid fractures are treated with cast immobilization and a small Pulsed Electromagnetic Fields bone growth stimulating device placed on the cast. Half of the devices will be disabled at random in the factory. Study parameters are clinical consolidation, radiological consolidation evaluated by CT-scanning, functional status of the wrist, including assessment by means of the patient rated wrist evaluation (PRWE) questionnaire and quality of life using SF-36 health survey questionnaire. Primary endpoint is number of scaphoid unions at six weeks, secondary endpoints are time interval to clinical and radiological consolidation, number of non-unions, functional status at 52 weeks and non-adherence to the treatment protocol. Trial registration Netherlands Trial Register (NTR): NTR2064 PMID:21548951
McCloskey, Eugene V; Beneton, Monique; Charlesworth, Diane; Kayan, Karthik; deTakats, Dominic; Dey, Abhijit; Orgee, Jane; Ashford, Robert; Forster, Martin; Cliffe, Jennifer; Kersh, Linda; Brazier, John; Nichol, Jon; Aropuu, Sakari; Jalava, Tarja; Kanis, John A
2007-01-01
A 3-year prospective, randomized, placebo-controlled trial of oral clodronate 800 mg showed that the incidence of clinical fractures was decreased by 20% in 5596 elderly women unselected for osteoporosis. The effect occurred in the absence of systematic calcium and vitamin D supplementation and was observed across a wide range of BMDs. To date, most studies with bisphosphonates have reported on their use in individuals selected to be at high risk for fracture usually by the presence of low BMD or a prior fragility fracture, usually of the spine. We wished to determine the effect of the bisphosphonate, clodronate, on the rate of fractures in women > or =75 years of age living in the community. Women > or =75 years of age living in the general community in South Yorkshire and North Derbyshire, identified from general practice registers, were recruited by letter of invitation to a randomized, double-blind, controlled trial of 800 mg oral clodronate (Bonefos) or matching placebo daily over 3 years. The main outcomes were the incidences of hip and any clinical fracture. Of the 5579 elderly women included in the intention-to-treat analysis of efficacy, 114 had a new hip fracture during the 3-year treatment phase: 56 (2.0%) women in the clodronate group and 58 (2.1%) women in the placebo group (hazard ration [HR], 1.02; 95% CI, 0.71-1.47). Clodronate did, however, decrease the incidence of any clinical fracture by 20% (264 women [9.5%] versus 337 [12.1%] in the placebo group; HR, 0.80; 95% CI, 0.68-0.94). The incidence of osteoporosis-associated nonhip fractures was also significantly decreased by 29% (5.2% versus 7.4%; HR, 0.71; 95% CI, 0.57-0.87). The ability of clodronate to reduce the risk of osteoporotic fracture was independent of baseline BMD, but the number needed-to-treat was lower in the presence of osteoporosis. Oral daily clodronate can prevent fractures without significant adverse effects in elderly women living in the general community. The effect on hip fracture risk is not significant, but an effect similar to that at other nonvertebral sites cannot be excluded. This study suggests that antiresorptive therapies can reduce fracture incidence in high-risk individuals even in the presence of a normal or osteopenic BMD.
Ceroni, Dimitri; Martin, Xavier; Delhumeau, Cécile; Rizzoli, René; Kaelin, André; Farpour-Lambert, Nathalie
2012-02-01
Leg or ankle fractures occur commonly in the pediatric population and are primarily treated with closed reduction and cast immobilization. The most predictable consequences of immobilization and subsequent weight-bearing restriction are loss of bone mineral mass, substantial muscle atrophy, and functional limitations. The purposes of this study were to determine if lower-limb fractures in adolescents are associated with abnormal bone mineral density or content at the time of fracture, and to quantify bone mineral loss at various sites due to cast-mediated immobilization and limited weight-bearing. We recruited fifty adolescents aged ten to sixteen years who had undergone cast immobilization for a leg or ankle fracture. Dual x-ray absorptiometry scans of the total body, lumbar spine, hip, leg, and calcaneus were performed at the time of fracture and at cast removal. Patients with a fracture were paired with healthy controls according to sex and age. Values at baseline and at cast removal, or at equivalent time intervals in the control group, were compared between groups and between the injured and uninjured legs of the adolescents with the fracture. At the time of fracture, there were no observed differences in the bone mineral density or bone mineral content Z-scores of the total body or the lumbar spine, or in the bone mineral density Z-scores of the calcaneus, between the injured and healthy subjects. At cast removal, bone mineral parameters on the injured side were significantly lower than those on the uninjured side in the injured group. Differences ranged from -5.8% to -31.7% for bone mineral density and from -5.2% to -19.4% for bone mineral content. During the cast period, the injured adolescents had a significant decrease of bone mineral density at the hip, greater trochanter, calcaneus, and total lower limb as compared with the healthy controls. Lower-limb fractures are not related to osteopenia in adolescents at the time of fracture. However, osteopenia does develop in the injured limb during cast immobilization for fracture treatment. Further investigation is required to determine if the bone mineral mass will return to normal or if a permanent decrease is to be expected, which may constitute a hypothetical risk of sustaining a second fracture.
Cavallazzi, Rodrigo; Cavallazzi, Antonio César
2008-01-01
To analyze the available evidence regarding the effect that corticosteroids have on the prevention of fat embolism syndrome after long bone fracture of the lower limbs or pelvic fracture. In March of 2007, we performed a search of various electronic databases, including Medline, the Excerpta Medica database, the Cochrane Library, the Latin American and Caribbean Health Sciences Literature database and the Scientific Electronic Library Online. We selected randomized controlled trials that compared the effect of corticosteroids with that of placebo (or standard care) on the prevention of fat embolism syndrome after long bone fracture of the lower limbs or pelvic fracture. References from the studies included were also reviewed. Six studies were included. The pooled relative risk for developing fat embolism syndrome was 0.16 (95% CI: 0.08-0.35) in the corticosteroid group as compared with the control group. The pooled relative risk for developing hypoxemia was 0.34 (95% CI: 0.19-0.59) in the corticosteroid group as compared with the control group. The analysis of evidence showed that corticosteroids decrease the risk of developing fat embolism syndrome and hypoxemia after long bone fracture of the lower limbs.
Femoral metastases from ovarian serous/endometroid adenocarcinoma
Beresford–Cleary, NJA; Mehdi, SA; Magowan, B
2012-01-01
Bony metastases from ovarian cancer are rare, tend to affect the axial skeleton and are associated with abdomino-pelvic disease. The median time interval between diagnosis of ovarian carcinoma and presentation of bony metastases is 44 months (1). We describe a rare case of high grade left ovarian serous / endometrioid adenocarcinoma presenting with a pathological right femoral fracture 4 weeks following diagnosis and optimal debulking of the ovarian tumour. Orthopaedic surgeons must be vigilant when planning treatment of fractures presenting in patients with a history of ovarian cancer. PMID:24960734
Work Plan for an Inpatient Rehabilitation Prospective Payment System
2000-01-01
through 4.23 5 Nontraumatic spinal cord 4.1,4.11 through 4.13 6 Neurological 3.1,3.2,3.3,3.5,3.8,3.9 7 Hip fracture 8.11 through 8.4 8 Replacement of...Eilertsen, C. A. Hrincevich, D. A. Tropea, L. A. Ahmad, and D. G. Eckhoff, "Outcomes and Costs After Hip Fracture and Stroke: A Comparison of...Teaching Costs 53 Low Income Patients 55 Other Factors Affecting Cost 58 Multivariate Regression Analysis 59 8. SIMULATIONS AND IMPACT ANALYSES 60 Data
Intensive glycemic control is not associated with fractures or falls in the ACCORD randomized trial.
Schwartz, Ann V; Margolis, Karen L; Sellmeyer, Deborah E; Vittinghoff, Eric; Ambrosius, Walter T; Bonds, Denise E; Josse, Robert G; Schnall, Adrian M; Simmons, Debra L; Hue, Trisha F; Palermo, Lisa; Hamilton, Bruce P; Green, Jennifer B; Atkinson, Hal H; O'Connor, Patrick J; Force, Rex W; Bauer, Douglas C
2012-07-01
Older adults with type 2 diabetes are at high risk of fractures and falls, but the effect of glycemic control on these outcomes is unknown. To determine the effect of intensive versus standard glycemic control, we assessed fractures and falls as outcomes in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) randomized trial. ACCORD participants were randomized to intensive or standard glycemia strategies, with an achieved median A1C of 6.4 and 7.5%, respectively. In the ACCORD BONE ancillary study, fractures were assessed at 54 of the 77 ACCORD clinical sites that included 7,287 of the 10,251 ACCORD participants. At annual visits, 6,782 participants were asked about falls in the previous year. During an average follow-up of 3.8 (SD 1.3) years, 198 of 3,655 participants in the intensive glycemia and 189 of 3,632 participants in the standard glycemia group experienced at least one nonspine fracture. The average rate of first nonspine fracture was 13.9 and 13.3 per 1,000 person-years in the intensive and standard groups, respectively (hazard ratio 1.04 [95% CI 0.86-1.27]). During an average follow-up of 2.0 years, 1,122 of 3,364 intensive- and 1,133 of 3,418 standard-therapy participants reported at least one fall. The average rate of falls was 60.8 and 55.3 per 100 person-years in the intensive and standard glycemia groups, respectively (1.10 [0.84-1.43]). Compared with standard glycemia, intensive glycemia did not increase or decrease fracture or fall risk in ACCORD.
Xu, M T; Sun, S; Zhang, L; Xu, F; Du, S L; Zhang, X D; Wang, D W
2016-01-01
Transforming growth factor beta 1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2) are important regulators of bone repair and regeneration. In this study, we examined whether TGF-β1 and BMP-2 expressions were delayed during bone healing in type 1 diabetes mellitus. Tibial fractures were created in 95 diabetic and 95 control adult male Wistar rats of 10 weeks of age. At 1, 2, 3, 4, and 5 weeks after fracture induction, five rats were sacrificed from each group. The expressions of TGF-β1 and BMP2 in the fractured tibias were measured by immunohistochemistry and quantitative reverse-transcription polymerase chain reaction, weekly for the first 5 weeks post-fracture. Mechanical parameters (bending rigidity, torsional rigidity, destruction torque) of the healing bones were also assessed at 3, 4, and 5 weeks post-fracture, after the rats were sacrificed. The bending rigidity, torsional rigidity and destruction torque of the two groups increased continuously during the healing process. The diabetes group had lower mean values for bending rigidity, torsional rigidity and destruction torque compared with the control group (P<0.05). TGF-β1 and BMP-2 expression were significantly lower (P<0.05) in the control group than in the diabetes group at postoperative weeks 1, 2, and 3. Peak levels of TGF-β1 and BMP-2 expression were delayed by 1 week in the diabetes group compared with the control group. Our results demonstrate that there was a delayed recovery in the biomechanical function of the fractured bones in diabetic rats. This delay may be associated with a delayed expression of the growth factors TGF-β1 and BMP-2.
Effects of Boric Acid on Fracture Healing: An Experimental Study.
Gölge, Umut Hatay; Kaymaz, Burak; Arpaci, Rabia; Kömürcü, Erkam; Göksel, Ferdi; Güven, Mustafa; Güzel, Yunus; Cevizci, Sibel
2015-10-01
Boric acid (BA) has positive effects on bone tissue. In this study, the effects of BA on fracture healing were evaluated in an animal model. Standard closed femoral shaft fractures were created in 40 male Sprague-Dawley rats under general anesthesia. The rats were allocated into five groups (n = 8 each): group 1, control with no BA; groups 2 and 3, oral BA at doses of 4 and 8 mg/kg/day, respectively; group 4, local BA (8 mg/kg); and group 5, both oral and local BA (8 mg/kg/day orally and 8 mg/kg locally). After closed fracture creation, the fracture line was opened with a mini-incision, and BA was locally administered to the fracture area in groups 4 and 5. In groups 2, 3, and 5, BA was administered by gastric gavage daily until sacrifice. The rats were evaluated by clinical, radiological, and histological examinations. The control group (group 1) significantly differed from the local BA-exposed groups (groups 4 and 5) in the clinical evaluation. Front-rear and lateral radiographs revealed significant differences between the local BA-exposed groups and the control and other groups (p < 0.05). Clinical and radiological evaluations demonstrated adequate agreement between observers. The average histological scores significantly differed across groups (p = 0.007) and were significantly higher in groups 4 and 5 which were the local BA (8 mg/kg) and both oral and local BA (8 mg/kg/day orally and 8 mg/kg locally), respectively, compared to the controls. This study suggests that BA may be useful in fracture healing. Further research is required to demonstrate the most effective local dosage and possible use of BA-coated implants.
Milovanovic, Petar; Rakocevic, Zlatko; Djonic, Danijela; Zivkovic, Vladimir; Hahn, Michael; Nikolic, Slobodan; Amling, Michael; Busse, Bjoern; Djuric, Marija
2014-07-01
To unravel the origins of decreased bone strength in the superolateral femoral neck, we assessed bone structural features across multiple length scales at this cortical fracture initiating region in postmenopausal women with hip fracture and in aged-matched controls. Our combined methodological approach encompassed atomic force microscopy (AFM) characterization of cortical bone nano-structure, assessment of mineral content/distribution via quantitative backscattered electron imaging (qBEI), measurement of bone material properties by reference point indentation, as well as evaluation of cortical micro-architecture and osteocyte lacunar density. Our findings revealed a wide range of differences between the fracture group and the controls, suggesting a number of detrimental changes at various levels of cortical bone hierarchical organization that may render bone fragile. Namely, mineral crystals at external cortical bone surfaces of the fracture group were larger (65.22nm±41.21nm vs. 36.75nm±18.49nm, p<0.001), and a shift to a higher mineral content and more homogenous mineralization profile as revealed via qBEI were found in the bone matrix of the fracture group. Fracture cases showed nearly 35% higher cortical porosity and showed significantly reduced osteocyte lacunar density compared to controls (226±27 vs. 247±32#/mm(2), p=0.05). Along with increased crystal size, a shift towards higher mineralization and a tendency to increased cortical porosity and reduced osteocyte lacunar number delineate that cortical bone of the superolateral femoral neck bears distinct signs of fragility at various levels of its structural organization. These results contribute to the understanding of hierarchical bone structure changes in age-related fragility. Copyright © 2014 Elsevier Inc. All rights reserved.
[Association between hip fractures and risk factors for osteoporosis. Multivariate analysis].
Masoni, Ana; Morosano, Mario; Tomat, María Florencia; Pezzotto, Stella M; Sánchez, Ariel
2007-01-01
In this observational, case-control study, 376 inpatients were evaluated in order to determine the association of risk factors (RF) and hip fracture; 151 patients had osteoporotic hip fracture (cases); the remaining were controls. Data were obtained from medical charts, and through a standardized questionnaire about RF. Mean age of the sample (+/- SD) was 80.6 +/- 8.1 years, without statistically significant difference between cases and controls; the female:male ratio was 3:1 in both groups. Fractured women were older than men (82.5 +/- 8.1 vs. 79.7 +/- 7.2 years, respectively; p < 0.01). Physical activity, intake of alcohol and tobacco, and sun exposure were low in all patients. Falls among cases happened predominantly at home (p < 0.001). Among female cases, time spent in household duties was a RF (p = 0.007), which was absent in males. In multivariate analysis, the following RF were significantly more frequent: Cognitive impairment (p = 0.001), and previous falls (p < 0.0001); whereas the following protective factors were significantly different from controls: Calcium intake during youth (p < 0.0001), current calcium intake (p < 0.0001), and mechanical aid for walking (p < 0.0001). Evaluation of RF and protective factors may contribute to diminish the probability of hip fracture, through a modification of personal habits, and measures to prevent falls among elderly adults. Present information can help to develop local and national population-based strategies to diminish the burden of hip fractures for the health system.
Liu, Chen; Guan, Zhao; Xu, Qinzhu; Zhao, Lei; Song, Ying; Wang, Hui
2016-01-01
Abstract Fractures are common among aged people, and rapid assessment of the coagulation status is important. The thromboelastography (TEG) test can give a series of coagulation parameters and has been widely used in clinics. In this research, we looked at fracture patients over 60 and compared their TEG results with those of healthy controls. Since there is a paucity of studies comparing TEG assessments with conventional coagulation tests, we aim to clarify the relationship between TEG values and the values given by conventional coagulation tests. Forty fracture patients (27 femur and 13 humerus) over 60 years old were included in the study. The change in their coagulation status was evaluated by TEG before surgery within 4 hours after the fracture. Changes in TEG parameters were analyzed compared with controls. Conventional coagulation test results for the patients, including activated partial thromboplastin time (APTT), international normalized ratio (INR), fibrinogen, and platelets, were also acquired, and correlation analysis was done with TEG parameters, measuring similar aspects of the coagulation cascade. In addition, the sensitivity and specificity of TEG parameters for detecting raised fibrinogen levels were also analyzed. The K (time to 20 mm clot amplitude) and R (reaction time) values of aged fracture patients were lower than controls. The values for angle, maximal amplitude (MA), and coagulation index (CI) were raised compared with controls, indicating a hypercoagulable state. Correlation analysis showed that there were significant positive correlations between fibrinogen and MA/angle, between platelets and MA, and between APTT and R as well. There was significant negative correlation between fibrinogen and K. In addition, K values have better sensitivity and specificity for detecting elevated fibrinogen concentration than angle and MA values. Aged fracture patients tend to be in a hypercoagulable state, and this could be effectively reflected by a TEG test. There were correlations between TEG parameters and corresponding conventional tests. K values can better predict elevated fibrinogen levels in aged fracture patients. PMID:27311005
Liu, Chen; Guan, Zhao; Xu, Qinzhu; Zhao, Lei; Song, Ying; Wang, Hui
2016-06-01
Fractures are common among aged people, and rapid assessment of the coagulation status is important. The thromboelastography (TEG) test can give a series of coagulation parameters and has been widely used in clinics. In this research, we looked at fracture patients over 60 and compared their TEG results with those of healthy controls. Since there is a paucity of studies comparing TEG assessments with conventional coagulation tests, we aim to clarify the relationship between TEG values and the values given by conventional coagulation tests.Forty fracture patients (27 femur and 13 humerus) over 60 years old were included in the study. The change in their coagulation status was evaluated by TEG before surgery within 4 hours after the fracture. Changes in TEG parameters were analyzed compared with controls. Conventional coagulation test results for the patients, including activated partial thromboplastin time (APTT), international normalized ratio (INR), fibrinogen, and platelets, were also acquired, and correlation analysis was done with TEG parameters, measuring similar aspects of the coagulation cascade. In addition, the sensitivity and specificity of TEG parameters for detecting raised fibrinogen levels were also analyzed.The K (time to 20 mm clot amplitude) and R (reaction time) values of aged fracture patients were lower than controls. The values for angle, maximal amplitude (MA), and coagulation index (CI) were raised compared with controls, indicating a hypercoagulable state. Correlation analysis showed that there were significant positive correlations between fibrinogen and MA/angle, between platelets and MA, and between APTT and R as well. There was significant negative correlation between fibrinogen and K. In addition, K values have better sensitivity and specificity for detecting elevated fibrinogen concentration than angle and MA values.Aged fracture patients tend to be in a hypercoagulable state, and this could be effectively reflected by a TEG test. There were correlations between TEG parameters and corresponding conventional tests. K values can better predict elevated fibrinogen levels in aged fracture patients.
Effects of solar radiation on glass
NASA Technical Reports Server (NTRS)
Tucker, Dennis S.; Kinser, Donald L.
1991-01-01
The effects of solar radiation of selected glasses are reported. Optical property degradation is studied using UV-Vis spectrophotometry. Strength changes are measured using a concentric ring bend test. Direct fracture toughness measurements using an indentation test are planned.
Functional assessment of a surgical robot for reduction of lower limb fractures.
Hung, Shuo-Suei; Lee, Ming-Yih
2010-12-01
This paper presents a novel robot designed for reduction of lower limb fractures, with the additional features of automatic controlled flexion of the knee joint, individual traction of thigh and leg, and foot rotation. The aim of this design is to assist the orthopaedic surgeon to perform better fracture reduction through motor control, in contrast to current manual control, and the results of assessments of its functions on normal subjects are presented in this paper. The robot was designed to be mounted onto the operation table, and was controlled through open switch relay. Functional assessments were conducted on six healthy volunteers in terms of knee joint motion and lower limb traction; measurement of angle and distance was calculated from data obtained by a 3D ultrasonic motion system (Zebris(®) ). The results showed a good correlation of the flexion angle between the robot and the subjects at the knee joint. In the traction tests, a steady lengthening of the proximal as well as the distal segment of the robot was observed, and a slight increase in subjects' limb length was also recorded, which might be due to distraction in the joint space. This automatic control fracture table has distinct features compared with the conventional ones, and it is believed to be of assistance to surgeons when performing fracture fixations. Copyright © 2010 John Wiley & Sons, Ltd.
Study on interaction between induced and natural fractures by extended finite element method
NASA Astrophysics Data System (ADS)
Xu, DanDan; Liu, ZhanLi; Zhuang, Zhuo; Zeng, QingLei; Wang, Tao
2017-02-01
Fracking is one of the kernel technologies in the remarkable shale gas revolution. The extended finite element method is used in this paper to numerically investigate the interaction between hydraulic and natural fractures, which is an important issue of the enigmatic fracture network formation in fracking. The criteria which control the opening of natural fracture and crossing of hydraulic fracture are tentatively presented. Influence factors on the interaction process are systematically analyzed, which include the approach angle, anisotropy of in-situ stress and fluid pressure profile.
2015-10-01
stiffness, or a partial snap with lower yield force and stiffness (Figure 4). Three dimensional micro CT analysis around fracture Figure 3. (a-b... fractures with plate fixation on both sides and irradiation on the left while the contralateral limb serves as a non-radiated internal control. The...AWARD NUMBER: W81XWH-13-1-0430 TITLE: Optimal Treatment of Malignant Long Bone Fracture : Influence of Method of Repair and External Beam
Comparing slow and fast rupture in laboratory experiments
NASA Astrophysics Data System (ADS)
Aben, F. M.; Brantut, N.; David, E.; Mitchell, T. M.
2017-12-01
During the brittle failure of rock, elastically stored energy is converted into a localized fracture plane and surrounding fracture damage, seismic radiation, and thermal energy. However, the partitioning of energy might vary with the rate of elastic energy release during failure. Here, we present the results of controlled (slow) and dynamic (fast) rupture experiments on dry Lanhélin granite and Westerly granite samples, performed under triaxial stress conditions at confining pressures of 50 and 100 MPa. During the tests, we measured sample shortening, axial load and local strains (with 2 pairs of strain gauges glued directly onto the sample). In addition, acoustic emissions (AEs) and changes in seismic velocities were monitored. The AE rate was used as an indicator to manually control the axial load on the sample to stabilize rupture in the quasi-static failure experiments. For the dynamic rupture experiments a constant strain rate of 10-5 s-1 was applied until sample failure. A third experiment, labeled semi-controlled rupture, involved controlled rupture up to a point where the rupture became unstable and the remaining elastic energy was released dynamically. All experiments were concluded after a macroscopic fracture had developed across the whole sample and frictional sliding commenced. Post-mortem samples were epoxied, cut and polished to reveal the macroscopic fracture and the surrounding damage zone. The samples failed with average rupture velocities varying from 5x10-6 m/s up to >> 0.1 m/s. The analyses of AE locations on the slow ruptures reveal that within Westerly granite samples - with a smaller grain size - fracture planes are disbanded in favor of other planes when a geometrical irregularity is encountered. For the coarser grained Lanhélin granite a single fracture plane is always formed, although irregularities are recognized as well. The semi-controlled experiments show that for both rock types the rupture can become unstable in response to these irregularities. In Westerly granite, slow rupture experiments tend to produce complex fracture patterns while during the dynamic rupture experiments secondary rupture planes are not formed. These findings show that grain or flaw size, flaw distribution, and rupture speed strongly influence fracture localization and propagation.
NASA Technical Reports Server (NTRS)
Moore, M. R.; Garfin, S. R.; Hargens, A. R.
1987-01-01
A 26-year-old man presented with ipsilateral femur and ankle fractures. The patient was treated with interlocking nail of his femur fracture, followed by open reduction and internal fixation of his ankle fracture under tourniquet control. Postoperatively, the patient developed compartment syndrome of his thigh with elevated pressures, requiring decompressive fasciotomies. This case illustrates the possible complication of treating a femur fracture with intramedullary nailing and then immediately applying a tourniquet to treat an ipsilateral extremity fracture. Because of the complication with this patient, we feel the procedure should be staged, or a tourniquet should be avoided if possible.
NASA Technical Reports Server (NTRS)
Manoharan, M.; Lewandowski, J. J.
1989-01-01
Recent results on the effects of matrix aging condition (matrix temper) and notch root radius on the measured fracture toughness of a SiC particulate reinforced aluminum alloy are reviewed. Stress intensity factors at catastrophic fracture were obtained for both underaged and overaged composites reveal. The linear relation found between apparent fracture toughness and the square root of the notch root radius implies a linear dependence of the crack opening displacement on the notch root radius. The results suggest a strain controlled fracture process, and indicate that there are differences in the fracture micromechanisms of the two aging conditions.
NASA Astrophysics Data System (ADS)
Schöpfer, Martin; Lehner, Florian; Grasemann, Bernhard; Kaserer, Klemens; Hinsch, Ralph
2017-04-01
John G. Ramsay's sketch of structures developed in a layer progressively folded and deformed by tangential longitudinal strain (Figure 7-65 in Folding and Fracturing of Rocks) and the associated strain pattern analysis have been reproduced in many monographs on Structural Geology and are referred to in numerous publications. Although the origin of outer-arc extension fractures is well-understood and documented in many natural examples, geomechanical factors controlling their (finite or saturation) spacing are hitherto unexplored. This study investigates the formation of bending-induced fractures during constant-curvature forced folding using Distinct Element Method (DEM) numerical modelling. The DEM model comprises a central brittle layer embedded within weaker (low modulus) elastic layers; the layer interfaces are frictionless (free slip). Folding of this three-layer system is enforced by a velocity boundary condition at the model base, while a constant overburden pressure is maintained at the model top. The models illustrate several key stages of fracture array development: (i) Prior to the onset of fracture, the neutral surface is located midway between the layer boundaries; (ii) A first set of regularly spaced fractures develops once the tensile stress in the outer-arc equals the tensile strength of the layer. Since the layer boundaries are frictionless, these bending-induced fractures propagate through the entire layer; (iii) After the appearance of the first fracture set, the rate of fracture formation decreases rapidly and so-called infill fractures develop approximately midway between two existing fractures (sequential infilling); (iv) Eventually no new fractures form, irrespective of any further increase in fold curvature (fracture saturation). Analysis of the interfacial normal stress distributions suggests that at saturation the fracture-bound blocks are subjected to a loading condition similar to three-point bending. Using classical beam theory an analytical solution is derived for the critical fracture spacing, i.e. the spacing below which the maximum tensile stress cannot reach the layer strength. The model results are consistent with an approximate analytical solution, and illustrate that the spacing of bending-induced fractures is proportional to layer thickness and a square root function of the ratio of layer tensile strength to confining pressure. Although highly idealised, models and analysis presented in this study offer an explanation for fracture saturation during folding and point towards certain key factors that may control fracture spacing in natural systems.
Hip fractures. Epidemiology, risk factors, falls, energy absorption, hip protectors, and prevention.
Lauritzen, J B
1997-04-01
The present review summarizes the pathogenic mechanisms leading to hip fracture based on epidemiological, experimental, and controlled studies. The estimated lifetime risk of hip fracture is about 14% in postmenopausal women and 6% in men. The incidence of hip fractures increases exponentially with aging, but the time-trend in increasing age-specific incidence may not be a universal phenomenon. Postmenopausal women suffering earlier non-hip fractures have an increased risk of later hip fracture. The relative risk being highest within the first years following the fracture. Nursing home residents have a high risk of hip fracture (annual rate of 5-6%), and the incidence of falls is about 1,500 falls/1,000 persons/year. Most hip fractures are a result of a direct trauma against the hip. The incidence of falls on the hip among nursing home residents is about 290 falls/1,000 persons/year and about 24% of these impacts lead to hip fracture. The force acting on the hip may reach 3.7 kN in falls on the hip from standing height, which means that only susceptible subjects will sustain a hip fracture in such falls. The effective load acting on the hip is 35% of the body weight in unprotected falls on the hip. Women with hip fractures have a lower body weight compared with controls, and they may also have less soft tissue covering the hip even when adjusted for body mass index, indicating a more android body habitus. Experimental studies show that the passive energy absorption in soft tissue covering the hip may influence the risk of hip fracture, and being an important determinant for the development of hip fracture, maybe more important than bone strength. External hip protectors were developed and tested in an open randomised nursing home study. The rate of hip fractures was reduced by 50%, corresponding to 9 out of 247 residents saved from sustaining a hip fracture. The review points to the essentials of the development of hip fracture, which constitutes; risk of fall, type of fall, type of impact, energy absorption, and lastly bone strength, which is the ultimate and last permissive factor in the cascade leading to hip fracture. Risk estimation and prevention of hip fractures may prove realistic when these issues are taken into consideration.
Physical simulation study on the hydraulic fracture propagation of coalbed methane well
NASA Astrophysics Data System (ADS)
Wu, Caifang; Zhang, Xiaoyang; Wang, Meng; Zhou, Longgang; Jiang, Wei
2018-03-01
As the most widely used technique to modify reservoirs in the exploitation of unconventional natural gas, hydraulic fracturing could effectively raise the production of CBM wells. To study the propagation rules of hydraulic fractures, analyze the fracture morphology, and obtain the controlling factors, a physical simulation experiment was conducted with a tri-axial hydraulic fracturing test system. In this experiment, the fracturing sample - including the roof, the floor, and the surrounding rock - was prepared from coal and similar materials, and the whole fracturing process was monitored by an acoustic emission instrument. The results demonstrated that the number of hydraulic fractures in coal is considerably higher than that observed in other parts, and the fracture morphology was complex. Vertical fractures were interwoven with horizontal fractures, forming a connected network. With the injection of fracturing fluid, a new hydraulic fracture was produced and it extended along the preexisting fractures. The fracture propagation was a discontinuous, dynamic process. Furthermore, in-situ stress plays a key role in fracture propagation, causing the fractures to extend in a direction perpendicular to the minimum principal stress. To a certain extent, the different mechanical properties of the coal and the other components inhibited the vertical propagation of hydraulic fractures. Nonetheless, the vertical stress and the interfacial property are the major factors to influence the formation of the "T" shaped and "工" shaped fractures.
Postural profile and falls of osteoporotic women.
Karakasidou, Palina; Skordilis, Emmanouil K; Dontas, Ismene; Lyritis, George P
2012-01-01
1. To compare postural alignment in erect standing between osteoporotic fallers, osteoporotic non-fallers and healthy women. 2. To compare BMI, number of fractures and intensity of pain between osteoporotic fallers and non-fallers. Thirty-six osteoporotic women with vertebral fractures and 40 healthy women participated in the study. Spinal curvatures were assessed with a digital inclinometer. Photographic measurements of knee, hip, shoulder and head were carried out in sagittal plane. Significant differences were found between osteoporotic fallers and healthy women in the head (p=0.040), and thoracic angles (p=0.001). Significant differences were found between fallers and non-fallers in BMI (p=0.000), number of fractures (p=0.033) and pain (p=0.005), with fallers being heavier, with less fractures and pain than non-fallers. Osteoporotic fallers probably differ from osteoporotic non-fallers and healthy women. Researchers and clinicians may consider, in the future, the above differences when planning research and clinical intervention in this field. Replication studies are necessary to confirm the present findings.
Major neurovascular complications of clavicle fracture surgery
Clitherow, Harry DS
2014-01-01
Clavicle fracture fixation is becoming an increasingly common operation, with good clinical outcomes and a low rate of significant complications. However, there are several reports of rare but potentially life or limb threatening, neurovascular complications. Arterial injuries are usually pseudoaneurysms associated with prominent screws. These may be clinically silent for several years before presenting as subcritical upper limb ischaemia. Venous injuries are a result of tearing of the vessel wall by fracture manipulation, drills or implants. This produces intra-operative haemorrhage and potentially air embolism, which can be fatal if not rapidly recognized and managed. Brachial plexopathy is the result of traction on adherent plexus or impingement by fracture fragments or callus. It presents as severe arm pain and paralysis immediately postoperatively. Neurovascular injuries can be avoided by a combination of pre-operative planning, communication with anaesthetic staff and strategic surgical technique. The plane of the surgical exposure, release of the soft tissues, drill direction and depth and screw length are all important factors. PMID:27582950
The effect of luting media on the fracture resistance of a flame sprayed all-ceramic crown.
Casson, A M; Glyn Jones, J C; Youngson, C C; Wood, D J
2001-11-01
This in vitro study investigated the effect of selected luting media on the fracture resistance of a flame-sprayed all-ceramic crown. Three groups of 10 human upper premolar teeth were prepared for crowning using a standardised technique. Flame sprayed crowns were fabricated and cemented onto the preparations using zinc phosphate (ZPC), glass polyalkenoate (GPC) or composite luting cement (CLC). During crown seating, a pressure perfusion system simulated pulpal fluid outflow equivalent to 300mm of H2O. Compressive fracture resistance was determined for each group using a Universal Testing Machine with a crosshead speed of 1mm min(-1). A group of unrestored teeth acted as a control. The fracture resistance of the groups ranked as follows: ZPC>CLC>GPC=unrestored teeth. The difference between the fracture resistance of ZPC and CLC groups and the control group was statistically significant. The mode of fracture between the luted crowns and natural crowns was markedly different. When tested in compression, a new, flame-sprayed all-ceramic crown, when luted in place using ZPC, GPC or CLC, could produce strengths comparable to or greater than natural unrestored teeth. The luting agent used significantly affected the recorded fracture loads.
Frictional stability-permeability relationships for fractures in shales
NASA Astrophysics Data System (ADS)
Fang, Yi; Elsworth, Derek; Wang, Chaoyi; Ishibashi, Takuya; Fitts, Jeffrey P.
2017-03-01
There is wide concern that fluid injection in the subsurface, such as for the stimulation of shale reservoirs or for geological CO2 sequestration (GCS), has the potential to induce seismicity that may change reservoir permeability due to fault slip. However, the impact of induced seismicity on fracture permeability evolution remains unclear due to the spectrum of modes of fault reactivation (e.g., stable versus unstable). As seismicity is controlled by the frictional response of fractures, we explore friction-stability-permeability relationships through the concurrent measurement of frictional and hydraulic properties of artificial fractures in Green River shale (GRS) and Opalinus shale (OPS). We observe that carbonate-rich GRS shows higher frictional strength but weak neutral frictional stability. The GRS fracture permeability declines during shearing while an increased sliding velocity reduces the rate of permeability decline. By comparison, the phyllosilicate-rich OPS has lower friction and strong stability while the fracture permeability is reduced due to the swelling behavior that dominates over the shearing induced permeability reduction. Hence, we conclude that the friction-stability-permeability relationship of a fracture is largely controlled by mineral composition and that shale mineral compositions with strong frictional stability may be particularly subject to permanent permeability reduction during fluid infiltration.
Dobbe, J G G; Vroemen, J C; Strackee, S D; Streekstra, G J
2014-11-01
Preoperative three-dimensional planning methods have been described extensively. However, transferring the virtual plan to the patient is often challenging. In this report, we describe the management of a severely malunited distal radius fracture using a patient-specific plate for accurate spatial positioning and fixation. Twenty months postoperatively the patient shows almost painless reconstruction and a nearly normal range of motion.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guha, A.; Prasad, G.C.; Udupa, K.N.
Scintillography and autoradiography were used to study the healing of humeral fractures in rats injected with Sr/sup 85/. Among various agents studied for an influence on the rate of fracture healing, the total extract of the herb Cissus quadrangularis was tested. In both controls and animals receiving C. quadrangularis extract there was demineralization of the fractured bone at the site of fracture. In the treated group, there was a somewhat earlier rise in Sr/ sup 85/ uptake just after the first injection. Thereafter, uptake again became high, similar to the control samples from the 6th day onward. The maximum uptakemore » of control bone was found to be around the 19th day after fracturing, while in the treated group, maximum uptake was on 15th day. Though there was a minor difference in the period of maximum uptake between treated and control bone, the rate of uptake in the treated sample was markedly higher than that of the control sample. The fall of Sr/sup 85/ uptake in the treated bone was very rapid, whereas in the untreated animals it was more gradual. All these findings on the uptake of Sr/sup 85/ as measured by a G-M counter, corroborated x-ray pictures and gross autoradiography at different stages of fracture healing. The radiological and autoradiographic findings also clearly showed that the healing in the treated group was quicker than in the controls. Furthermore, the callus in the treated animals underwent remodeling processes much earlier than in the nontreated ones. It is concluded that if the uptake of Sr in the treated andimals is greater thand in the control samples at the site of fracture, healing activity is more pronounced. However, studies on patients have shown that the uptake of Sr/sup 85/ alone in the fractured region may not give an accurate picture of the healing processes. Thus, at the end of first week after fractures, accretion rate of Ca reached a peak and thereafter remained higher than normal throughout the period of healing. But when these results were compared with x-ray pictures, it was observed that the accretion rate in poorly uniting fractures did not diifer from that of normally healing fractures, so that in interpreting the rate of healing by the uptake of Sr/sup 85/, radiography is also required to make the correct assessment of the status of fracture healing. The Sr/sup 85/ uptake curves show that the uptake pattern can be divided into three definite phases. ln the first phase, which lasts for six days, there is and enormous amount of decalcification from the broken fragments of bone possibly due to increased vascularity of the region, and also to the increased accumulation of mucopolysaccharides locally. In the second phase, which lasts for another 8 to 12 days, rapid increase in the accretion of Ca as evidenced by increase in the uptake of Sr/sup 85/ noted. During the 2nd phase, histologic studies indicated that large amounts of collagen fibers appear, which possibly combine with all the available Ca salts there. The third phase shows a rapid fall of Sr/sup 85/ uptake, indicating that the callus formed in the second phase is rapidly being remodeled. (BBB)« less
Gravity-Driven Hydraulic Fractures
NASA Astrophysics Data System (ADS)
Germanovich, L. N.; Garagash, D.; Murdoch, L. C.; Robinowitz, M.
2014-12-01
This study is motived by a new method for disposing of nuclear waste by injecting it as a dense slurry into a hydraulic fracture that grows downward to great enough depth to permanently isolate the waste. Disposing of nuclear waste using gravity-driven hydraulic fractures is mechanically similar to the upward growth of dikes filled with low density magma. A fundamental question in both applications is how the injected fluid controls the propagation dynamics and fracture geometry (depth and breadth) in three dimensions. Analog experiments in gelatin [e.g., Heimpel and Olson, 1994; Taisne and Tait, 2009] show that fracture breadth (the short horizontal dimension) remains nearly stationary when the process in the fracture "head" (where breadth is controlled) is dominated by solid toughness, whereas viscous fluid dissipation is dominant in the fracture tail. We model propagation of the resulting gravity-driven (buoyant or sinking), finger-like fracture of stationary breadth with slowly varying opening along the crack length. The elastic response to fluid loading in a horizontal cross-section is local and can be treated similar to the classical Perkins-Kern-Nordgren (PKN) model of hydraulic fracturing. The propagation condition for a finger-like crack is based on balancing the global energy release rate due to a unit crack extension with the rock fracture toughness. It allows us to relate the net fluid pressure at the tip to the fracture breadth and rock toughness. Unlike the PKN fracture, where breadth is known a priori, the final breadth of a finger-like fracture is a result of processes in the fracture head. Because the head is much more open than the tail, viscous pressure drop in the head can be neglected leading to a 3D analog of Weertman's hydrostatic pulse. This requires relaxing the local elasticity assumption of the PKN model in the fracture head. As a result, we resolve the breadth, and then match the viscosity-dominated tail with the 3-D, toughness-dominated head to obtain a complete closed-form solution. We then analyze the gravity fracture propagation in conditions of either continuous injection or finite volume release for sets of parameters representative of dense waste injection technique and low viscosity magma diking.
Fall with and without fracture in elderly: what's different?
Kantayaporn, Choochat
2012-10-01
Falling fracture was one of the health problems in elderly. This presentation aimed to identify the factors of fall that caused fractures. The retrospective case-control study was designed. Samples were all who experienced fall within 1 year in Lamphun. Factors included age, gender underlying diseases, chronic drugs used, history of parent fragility fracture, age of menopause, steroid used, body mass index, visual acuity and time up and go test were studied. Multivariate regression analysis was used. 336 cases of fractures in 1,244 cases of fall were found. Significant factors of falling fracture group that were different from fall without fracture group included age, female gender, menopause before age of 45 and visual impairment. Visual impairment was the other key factor rather than osteoporosis that caused fall with fracture. The author suggested that falling fracture prevention programs should be included correction of visual impairment other than osteoporosis treatment.
Recovery of decreased bone mineral mass after lower-limb fractures in adolescents.
Ceroni, Dimitri; Martin, Xavier E; Delhumeau, Cécile; Farpour-Lambert, Nathalie J; De Coulon, Geraldo; Dubois-Ferrière, Victor; Rizzoli, René
2013-06-05
Loss of bone mineral mass, muscle atrophy, and functional limitations are predictable consequences of immobilization and subsequent weight-bearing restriction due to leg or ankle fractures. The aim of this study was to prospectively determine whether decreased bone mineral mass following lower-limb fractures recovers at follow-up durations of six and eighteen months in adolescents. In the present study, we included fifty adolescents who underwent cast immobilization for a leg or ankle fracture. Dual x-ray absorptiometry scans of four different sites (total hip, femoral neck, entire lower limb, and calcaneus) were performed at the time of the fracture, at cast removal, and at follow-ups of six and eighteen months. Patients with fractures were paired with healthy controls according to sex, age, and ethnicity. Dual x-ray absorptiometry values were compared between groups and between injured and non-injured legs in adolescents with fractures. Among those with fractures, lower-limb bone mineral variables were significantly lower at the injured side compared with the non-injured side at cast removal, with differences ranging from 6.2% to 31.7% (p < 0.0001). Similarly, injured adolescents had significantly lower bone mineral values at the level of the injured lower limb compared with healthy controls (p < 0.0001). At the six-month follow-up, there were still significant residual differences between injured and non-injured legs in adolescents with fractures (p < 0.0001). However, a significant residual difference between healthy controls and injured adolescents was present only for femoral neck bone mineral density (p = 0.011). At the eighteen-month follow-up, no significant difference was observed at any lower-limb site. Bone mineral loss following a fracture of the lower limb in adolescents is highly significant and affects the lower limb both proximal to and distal to the fracture site. In contrast to observations in adults, a rapid bone mass reversal occurs with full bone recovery by eighteen months. Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.
Epidemic of fractures during a period of snow and ice: has anything changed 33 years on?
Al-Azzani, Waheeb; Adam Maliq Mak, Danial; Hodgson, Paul; Williams, Rhodri
2016-09-14
We reproduced a frequently cited study that was published in the British Medical Journal (BMJ) in 1981 assessing the extent of 'snow-and-ice' fractures during the winter period. This study aims to provide an insight into how things have changed within the same emergency department (ED) by comparing the findings of the BMJ paper published 33 years ago with the present date. As per the original study, all patients presenting to the ED with a radiological evidence of fracture during three different 4-day periods were included. The three 4-day periods included 4 days of snow-and-ice conditions and two control 4-day periods when snow and ice was not present; the first was 4 days within the same year, with a similar amount of sunshine hours, and the second was 4 days 1 calendar year later. To identify the frequency, distribution and pattern of fractures sustained in snow-and-ice conditions compared to control conditions as well as comparisons with the index study 33 years ago. A total of 293 patients with fractures were identified. Overall, there was a 2.20 (CI 1.7 to 3.0, p <0.01) increase in risk of fracture during snow-and-ice periods compared to control conditions. There was an increase (p <0.01) of fractures of the arm, forearm and wrist (RR 3.2 (CI 1.4 to 7.6) and 2.9 (CI 1.5 to 5.4) respectively). While the relative risk was not of the magnitude 33 years ago, the overall number of patients presenting with a fracture during snow-and-ice conditions remains more than double compared to control conditions. This highlights the need for improved understanding of the impact of increased fracture burden on hospitals and more effective preventative measures. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/