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Sample records for bone fractures

  1. Bone fracture repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100077.htm Bone fracture repair - series To use the sharing features on ... to slide 4 out of 4 Indications Overview Fractures of the bones are classified in a number ...

  2. Bone fracture repair - series (image)

    MedlinePlus

    ... main treatment options for bone fractures are: Casting Open reduction, and internal fixation- this involves a surgery to repair the fracture-frequently, metal rods, screws or plates are used to repair the bone, and remain ...

  3. Stress fractures and bone pain

    SciTech Connect

    Groshar, D.; Even-Sapir, E.; Lam, M.; Israel, O.; Front, D.

    1984-01-01

    Stress fractures result from an unusual repetitive physical activity causing absorption of bone in excess of repair and bone formation. This leads to the weakening of the bone and subsequently to a fracture. It is a benign condition that if recognized in time does not need any treatment besides rest. However, if diagnosis is not made and physical activity continues it may result in severe injury to the bone and a frank fracture may result. Pain is the typical clinical feature and bone scintigraphy, being more sensitive than radiography, is done to establish early diagnosis. The presence of asymptomatic sites of abnormal bone uptake typical of stress fracture in which pain appeared only about 2 weeks after scintigraphy, drew the authors' attention to the question of how close is the relationship between stress fractures and bone pain. Sixty-four military recruits diagnosed as suffering from stress fracture were investigated in order to correlate sites with abnormal uptake of Tc-99m MDP on bone scintigraphy with sites of local pain. In 37 (58%) subjects multiple sites of abnormal uptake were recognised. Of 123 sites of abnormal uptake, 31 (25%) were asymptomatic. In three patients bone pain appeared at the site of the abnormal uptake two weeks after scintigraphy. Bone scintigraphy appears to be more sensitive than bone pain in the diagnosis of stress fractures. The osteoblastic activity which manifests itself by abnormal uptake appears in some cases earlier than the pain caused by the fracture. Present findings may suggest that under certain circumstances, in a population prone to stress fracture, bone scan should be considered as a screening method.

  4. Bone fractures: assessment and management.

    PubMed

    Lim, L; Sirichai, P

    2016-03-01

    Severe dental traumatic injuries often involve the supporting bone and soft tissues. This article outlines the current concepts in the management of dentoalveolar fractures for the general dental practitioner with case reports to illustrate management principles and techniques. PMID:26923449

  5. Fracture healing in osteoporotic bone.

    PubMed

    Cheung, Wing Hoi; Miclau, Theodore; Chow, Simon Kwoon-Ho; Yang, Frank F; Alt, Volker

    2016-06-01

    As the world population rises, osteoporotic fracture is an emerging global threat to the well-being of elderly patients. The process of fracture healing by intramembranous ossification or/and endochondral ossification involve many well-orchestrated events including the signaling, recruitment and differentiation of mesenchymal stem cells (MSCs) during the early phase; formation of a hard callus and extracellular matrix, angiogenesis and revascularization during the mid-phase; and finally callus remodeling at the late phase of fracture healing. Through clinical and animal research, many of these factors are shown to be impaired in osteoporotic bone. Animal studies related to post-menopausal estrogen deficient osteoporosis (type I) have shown healing to be prolonged with decreased levels of MSCs and decreased levels of angiogenesis. Moreover, the expression of estrogen receptor (ER) was shown to be delayed in ovariectomy-induced osteoporotic fracture. This might be related to the observed difference in mechanical sensitivity between normal and osteoporotic bones, which requires further experiments to elucidate. In mice fracture models related to senile osteoporosis (type II), it was observed that chondrocyte and osteoblast differentiation were impaired; and that transplantation of juvenile bone marrow would result in enhanced callus formation. Other factors related to angiogenesis and vasculogenesis have also been noted to be impaired in aged models, affecting the degradation of cartilaginous matrixes and vascular invasion; the result is changes in matrix composition and growth factors concentrations that ultimately impairs healing during age-related osteoporosis. Most osteoporotic related fractures occur at metaphyseal sites clinically, and reports have indicated that differences exist between diaphyseal and metaphyseal fractures. An animal model that satisfies three main criteria (metaphyseal region, plate fixation, osteoporosis) is suggested for future research for

  6. Closed reduction of a fractured bone

    MedlinePlus

    Fracture reduction - closed ... Closed reduction is a procedure to set (reduce) a broken bone without surgery. This allows the bone ... soon as possible after the bone breaks. A closed reduction can be done by an orthopedic surgeon ( ...

  7. Fractures and Biomechanical Characteristics of the Bone

    PubMed Central

    Velnar, Tomaz; Bunc, Gorazd; Gradisnik, Lidija

    2016-01-01

    The biological tissue is affected by external and internal deformation forces: tractive/tensile forces, shearing and compressive forces. The bone is deformed under the effect of a force. If the load exceeds the bone solidity limitation, fracture occurs. A mature bone consists of compact and spongy bone tissue. The basic structural unit of the cortical bone tissue are osteons and spongiosa consists of a network of bone trabeculae. The organic and mineral parts of the bone are responsible for the special bone characteristics. The effect of a physical activity on the mechanical characteristics of the bone is associated with the intensity of the load. Fractures are more common in elderly people as the bone structure is altered on account of osteoporosis and contains less bone tissue. Biomechanical characteristics with anatomic and histological bone structure as well as osteoporotic hip fractures are described in the paper. PMID:27110433

  8. Ultrasonic monitoring of bone fracture healing.

    PubMed

    Protopappas, Vasilios C; Vavva, Maria G; Fotiadis, Dimitrios I; Malizos, Konstantinos N

    2008-01-01

    Quantitative ultrasound has attracted significant interest in the evaluation of bone fracture healing. Animal and clinical studies have demonstrated that the propagation velocity across fractured bones can be used as an indicator of healing. Researchers have recently employed computational methods for modeling wave propagation in bones, aiming to gain insight into the underlying mechanisms of wave propagation and to further enhance the monitoring capabilities of ultrasound. In this paper, we review the relevant literature and present the current status of knowledge. PMID:18599412

  9. Ulnar nerve paralysis after forearm bone fracture.

    PubMed

    Schwartsmann, Carlos Roberto; Ruschel, Paulo Henrique; Huyer, Rodrigo Guimarães

    2016-01-01

    Paralysis or nerve injury associated with fractures of forearm bones fracture is rare and is more common in exposed fractures with large soft-tissue injuries. Ulnar nerve paralysis is a rare condition associated with closed fractures of the forearm. In most cases, the cause of paralysis is nerve contusion, which evolves with neuropraxia. However, nerve lacerations and entrapment at the fracture site always need to be borne in mind. This becomes more important when neuropraxia appears or worsens after reduction of a closed fracture of the forearm has been completed. The importance of diagnosing this injury and differentiating its features lies in the fact that, depending on the type of lesion, different types of management will be chosen. PMID:27517030

  10. Periprosthetic fracture fixation in osteoporotic bone.

    PubMed

    Lenz, Mark; Lehmann, Wolfgang; Wähnert, Dirk

    2016-06-01

    Fixation techniques of periprosthetic fractures are far from ideal although the number of this entity is rising. The presence of an intramedullary implant generates its own fracture characteristics since stiffness is altered along the bone shaft and certain implant combinations affect load resistance of the bone. Influencing factors are cement fixation of the implant, intramedullary locking and extramedullary or intramedullary localization of the implant and the cortical thickness of the surrounding bone. Cerclage wires are ideally suited to fix radially displaced fragments around an intramedullary implant but they are susceptible to axial and torsional load. Screws should be added if these forces have to be neutralized. Stability of the screw fixation itself can be enhanced by embracement configuration around the intramedullary implant. Poor bone stock quality, often being present in metaphyseal areas limits screw fixation. Cement augmentation is an attractive option in this field to enhance screw purchase. PMID:27338227

  11. Fracture, aging and disease in bone

    SciTech Connect

    Ager, J.W.; Balooch, G.; Ritchie, R.O.

    2006-02-01

    From a public health perspective, developing a detailed mechanistic understanding of the well-known increase in fracture risk of human bone with age is essential. This also represents a challenge from materials science and fracture mechanics viewpoints. Bone has a complex, hierarchical structure with characteristic features ranging from nanometer to macroscopic dimensions; it is therefore significantly more complex than most engineering materials. Nevertheless, by examining the micro-/nano-structural changes accompanying the process of aging using appropriate multiscale experimental methods and relating them to fracture mechanics data, it is possible to obtain a quantitative picture of how bone resists fracture. As human cortical bone exhibits rising ex vivo crack-growth resistance with crack extension, its fracture toughness must be evaluated in terms of resistance-curve (R-curve) behavior. While the crack initiation toughness declines with age, the more striking finding is that the crack-growth toughness declines even more significantly and is essentially absent in bone from donors exceeding 85 years in age. To explain such an age-induced deterioration in the toughness of bone, we evaluate its fracture properties at multiple length scales, specifically at the molecular and nanodimensions using pico-force atomic-force microscopy, nanoindentation and vibrational spectroscopies, at the microscale using electron microscopy and hard/soft x-ray computed tomography, and at the macroscale using R-curve measurements. We show that the reduction in crack-growth toughness is associated primarily with a degradation in the degree of extrinsic toughening, in particular involving crack bridging, and that this occurs at relatively coarse size-scales in the range of tens to hundreds of micrometers. Finally, we briefly describe how specific clinical treatments, e.g., with steroid hormones to treat various inflammatory conditions, can prematurely damage bone, thereby reducing its

  12. Mechanistic fracture criteria for the failure of human cortical bone

    SciTech Connect

    Nalla, Ravi K.; Kinney, John H.; Ritchie, Robert O.

    2002-12-13

    A mechanistic understanding of fracture in human bone is critical to predicting fracture risk associated with age and disease. Despite extensive work, a mechanistic framework for describing how the underlying microstructure affects the failure mode in bone is lacking.

  13. [Talus fractures--fractures of the most important tarsal bone].

    PubMed

    Klaue, K

    2004-07-01

    The talus is the key bone of the foot due to its location between the ankle and the subtalar joints. Through the flexion and extension of the ankle joint, the talus is the "propulsive bone" situated at the root of the first ray and the hallux. Through the subtalar and talo-navicular joints, the talus allows the foot to be "suspended" using a fancy spring mechanism involving ligaments and tendons. The talus thus transmits forces through two important joints without any direct muscular constraint. The talo-calcaneo-navicular joint may be called the "coxa pedis" due to the anatomical and functional similitudes with the coxofemoral joint ("coxa pelvis"). Fractures of the talus are rare. Talus fractures can be classified in "central" and "peripheral" fractures. Central fractures occur through a strong axial blow provided that the ankle and coxa pedis are locked by extrinsic muscular contraction. Peripheral fractures instead occur in an extreme position of the ankle or the coxa pedis, with a subluxation or complete dislocation of one or more of those joints. Central fractures produce a bony solution of continuity in between at least two of the ankle, subtalar and talo-navicular joints. Peripheral fractures mostly do implement joint surfaces which are sheared off. Aim of treating talus fractures is precise and stable reduction of the fragments because most often, the fractures cross the articular layers. The surgical approaches are critical, especially in displaced central fractures, because the reduction may require visual control all around the bone. There are three approaches which might be used as single approaches or combined simultaneously: the anteromedial approach along the subtalar joint from the navicular to the retro-malleolar region, the anterolateral approach centered on the sinus tarsi (Ollier) and the postero-lateral approach (Gallie). In many cases, a joint distraction device may help visualization of the different joint spaces as well as assist reduction

  14. Nonsyndromic Isolated Temporal Bone Styloid Process Fracture

    PubMed Central

    Kermani, Hamed; Dehghani, Nima; Aghdashi, Farzad; Esmaeelinejad, Mohammad

    2016-01-01

    Introduction: Fracture of the styloid process (SP) of the temporal bone is a rare traumatic injury in normal individuals who are not suffering from Eagle’s syndrome. Diagnosis and management of this problem requires comprehensive knowledge about its signs and symptoms. This study aimed to present an isolated styloid process fracture in a nonsyndromic patient. Case Presentation: A 50-year-old male patient was referred to our department with a complaint of sore throat. However, presentation of the problem resembled the symptoms of temporomandibular joint disorder (TMD). Fracture of the SP of the temporal bone was detected on the radiographs. Conservative treatment was undertaken for the patient. The symptoms diminished after about four months. Conclusions: Physicians should be aware of the signs and symptoms of different pain sources to prevent misdiagnosis and maltreatment. PMID:27218052

  15. Drummer's fracture of the third metatarsal bone.

    PubMed

    Cusi, Mel; Tsung, Jason; Nouh, Fred; Wong, Louise; Mansberg, Robert; Van der Wall, Hans

    2007-09-01

    A 14-year-old girl presented with a painful right foot. She was an elite water-polo player and could recall no history of specific trauma to the foot. On close and persistent questioning, she admitted to having taken up playing the drums recently, with practice sessions of up to 4 h/d. She used the foot drum with her right foot and had noticed that this was becoming increasingly painful and prevented her playing the instrument for the last 2 days. Plain films of the foot were originally reported as normal, but revised to abnormal after the scintigraphic study. Bone scintigraphy confirmed a stress fracture of the right 3rd metatarsal bone. Stress fractures of the 3rd metatarsal bone are rare with only 2 previous reports in the literature. PMID:17710033

  16. Bone mineral density testing after fragility fracture

    PubMed Central

    Posen, Joshua; Beaton, Dorcas E.; Sale, Joanna; Bogoch, Earl R.

    2013-01-01

    Abstract Objective To determine the proportion of patients with fragility fractures who can be expected to have low bone mineral density (BMD) at the time of fracture and to assist FPs in deciding whether to refer patients for BMD testing. Data sources MEDLINE, EMBASE, and CINAHL were searched from the earliest available dates through September 2009. Study selection English-language articles reporting BMD test results of patients with fragility fractures who were managed in an orthopedic environment (eg, fracture clinic, emergency management by orthopedic surgeons, inpatients) were eligible for review. While the orthopedic environment has been identified as an ideal point for case finding, FPs are often responsible for investigation and treatment. Factors that potentially influenced BMD test results (eg, selection of fracture types, exclusion criteria) were identified. Studies with 2 or more selection factors of potential influence were flagged, and rates of low BMD were calculated including and excluding these studies. Synthesis The distribution of the proportion of persons with low BMD was summarized across studies using descriptive statistics. We calculated lower boundaries on this distribution, using standard statistical thresholds, to determine a lower threshold of the expected rate of low BMD. Conclusion Family physicians evaluating patients with fragility fractures can expect that at least two-thirds of patients with fragility fractures who are older than 50 years of age will have low BMD (T score ≤ −1.0). With this a priori expectation, FPs might more readily conduct a fracture risk assessment and pursue warranted fracture risk reduction strategies following fragility fracture. PMID:24336562

  17. Fractures and stresses in Bone Spring sandstones

    SciTech Connect

    Lorenz, J.C.; Warpinski, N.R.; Sattler, A.R.; Northrop, D.A.

    1990-09-01

    This project is a collaboration between Sandia National Laboratories and Harvey E. Yates Company being conducted under the auspices of the Oil Recovery Technology Partnership. The project seeks to apply perspectives related to the effects of natural fractures, stress, and sedimentology to the simulation and production of low-permeability gas reservoirs to low-permeability oil reservoirs as typified by the Bone Spring sandstones of the Permian Basin, southeast New Mexico. This report presents the results and analysis obtained in 1989 from 233 ft of oriented core, comprehensive suite of logs, various in situ stress measurements, and detailed well tests conducted in conjunction with the drilling of two development wells. Natural fractures were observed in core and logs in the interbed carbonates, but there was no direct evidence of fractures in the sandstones. However, production tests of the sandstones indicated permeabilities and behavior typical of a dual porosity reservoir. A general northeast trend for the maximum principal horizontal stress was observed in an elastic strain recovery measurements and in strikes of drilling-induced fractures; this direction is subparallel to the principal fracture trend observed in the interbed carbonates. Many of the results presented are believed to be new information for the Bone Spring sandstones. 57 figs., 18 tabs.

  18. Early Onset of Laying and Bumblefoot Favor Keel Bone Fractures

    PubMed Central

    Gebhardt-Henrich, Sabine G.; Fröhlich, Ernst K. F.

    2015-01-01

    Simple Summary Numerous studies have documented a high prevalence of keel bone fractures in laying hens. In this longitudinal study, 80 white and brown laying hens were regularly checked for keel bone deviations and fractures while egg production was individually monitored. About 62% of the hens had broken keel bones at depopulation. More new fractures occurred during the time when laying rates were highest. Hens with broken keel bones at depopulation had laid their first egg earlier than hens with intact keel bones. All birds with bumblefoot on both feet had a fracture at depopulation. Abstract Numerous studies have demonstrated influences of hybrid, feed, and housing on prevalence of keel bone fractures, but influences of behavior and production on an individual level are less known. In this longitudinal study, 80 white and brown laying hens were regularly checked for keel bone deviations and fractures while egg production was individually monitored using Radio Frequency Identification (RFID) from production until depopulation at 65 weeks of age. These focal birds were kept in eight pens with 20 hens per pen in total. About 62% of the hens had broken keel bones at depopulation. The occurrence of new fractures was temporally linked to egg laying: more new fractures occurred during the time when laying rates were highest. Hens with fractured keel bones at depopulation had laid their first egg earlier than hens with intact keel bones. However, the total number of eggs was neither correlated with the onset of egg laying nor with keel bone fractures. All birds with bumblefoot on both feet had a fracture at depopulation. Hens stayed in the nest for a longer time during egg laying during the ten days after the fracture than during the ten days before the fracture. In conclusion, a relationship between laying rates and keel bone fractures seems likely. PMID:26633520

  19. Central tarsal bone fracture in the border collie.

    PubMed

    Guilliard, M

    2007-07-01

    Fracture of the plantar process of the central tarsal bone together with a dorsomedial displacement of the body of the bone was seen in six border collies. All injuries occurred during free exercise, with no extrinsic trauma. Three dogs had concomitant tarsal fractures. Primary treatment was by lag screwing the central tarsal bone to the fourth tarsal bone. All cases eventually made an excellent recovery. The superficial radiographic appearance was of a luxation of the bone as reported in a previous series, but appraisal of the radiographs showed evidence of fracture in all cases. A cadaver study to assess the mechanism of luxation showed that it is unlikely to occur naturally. PMID:17490445

  20. Probabilistic Risk Assessment for Bone Fracture - Bone Fracture Risk Module (BFxRM)

    NASA Technical Reports Server (NTRS)

    Licata, Angelo; Myers, Jerry G.; Lewandowski, Beth

    2013-01-01

    This presentation summarizes the concepts, development, and application of NASA's Bone Fracture Risk Module (BFxRM). The overview includes an assessmnet of strenghts and limitations of the BFxRM and proposes a numebr of discussion questions to the panel regarding future development avenues for this simulation system.

  1. From brittle to ductile fracture of bone

    NASA Astrophysics Data System (ADS)

    Peterlik, Herwig; Roschger, Paul; Klaushofer, Klaus; Fratzl, Peter

    2006-01-01

    Toughness is crucial to the structural function of bone. Usually, the toughness of a material is not just determined by its composition, but by the ability of its microstructure to dissipate deformation energy without propagation of the crack. Polymers are often able to dissipate energy by viscoplastic flow or the formation of non-connected microcracks. In ceramics, well-known toughening mechanisms are based on crack ligament bridging and crack deflection. Interestingly, all these phenomena were identified in bone, which is a composite of a fibrous polymer (collagen) and ceramic nanoparticles (carbonated hydroxyapatite). Here, we use controlled crack-extension experiments to explain the influence of fibre orientation on steering the various toughening mechanisms. We find that the fracture energy changes by two orders of magnitude depending on the collagen orientation, and the angle between collagen and crack propagation direction is decisive in switching between different toughening mechanisms.

  2. Early Onset of Laying and Bumblefoot Favor Keel Bone Fractures.

    PubMed

    Gebhardt-Henrich, Sabine G; Fröhlich, Ernst K F

    2015-01-01

    Numerous studies have demonstrated influences of hybrid, feed, and housing on prevalence of keel bone fractures, but influences of behavior and production on an individual level are less known. In this longitudinal study, 80 white and brown laying hens were regularly checked for keel bone deviations and fractures while egg production was individually monitored using Radio Frequency Identification (RFID) from production until depopulation at 65 weeks of age. These focal birds were kept in eight pens with 20 hens per pen in total. About 62% of the hens had broken keel bones at depopulation. The occurrence of new fractures was temporally linked to egg laying: more new fractures occurred during the time when laying rates were highest. Hens with fractured keel bones at depopulation had laid their first egg earlier than hens with intact keel bones. However, the total number of eggs was neither correlated with the onset of egg laying nor with keel bone fractures. All birds with bumblefoot on both feet had a fracture at depopulation. Hens stayed in the nest for a longer time during egg laying during the ten days after the fracture than during the ten days before the fracture. In conclusion, a relationship between laying rates and keel bone fractures seems likely. PMID:26633520

  3. The fracture toughness of cancellous bone.

    PubMed

    Cook, R B; Zioupos, P

    2009-09-18

    The mechanical capacity and integrity of cancellous bone is crucial in osteoporosis, a condition which is set to become more prevalent with increasing lifespan and population sizes. The fracture toughness (FT) of cancellous bone has never been examined before and the conditions associated with the growth of a major crack through the lattice of cancellous bone, a cellular solid, may improve our understanding for structural integrity of this material. The aim of this study is to provide (i) basic data on cancellous bone FT and (ii) the experimental support for the hypothesis of Gibson, L.J., Ashby, M.F. [1997a. Chapter 10: Wood. In: Cellular Solids: Structure and Properties, second ed. Cambridge University Press, pp. 387-428; Gibson, L.J., Ashby, M.F., 1997b. Chapter 11: Cancellous Bone. In: Cellular Solids: Structure and Properties, second ed. Cambridge University Press, pp. 429-52] that the FT of cancellous bone tissue is governed by the density of the tissue to a power function of between one and two. 294 SENB and 121 DC(T) specimen were manufactured from 45 human femoral heads, 37 osteoporotic and 8 osteoarthritic, as well as 19 equine thoracic vertebrae. The samples were manufactured in two groups: the first aligned with the trabecular structure (A( parallel)), the second orientated at 90 degrees to the main trabecular orientation (A( perpendicular)). The samples were tested in either tensile or bending mode to provide values of the stress intensity factor (K). The results which were obtained show a strong and significant link between the density of the cancellous bone tissue and that the critical stress intensity values are governed by the density of the tissue to a power function of between 1 and 2 (K(Q) vs. apparent density: A( perpendicular)=1.58, A( parallel)=1.6). Our results provide some fundamental values for the critical stress intensity factor for cancellous bone and also support the previous hypothesis as set by Gibson, L.J., Ashby, M.F., 1997a

  4. Analyzing the cellular contribution of bone marrow to fracture healing using bone marrow transplantation in mice

    SciTech Connect

    Colnot, C. . E-mail: colnotc@orthosurg.ucsf.edu; Huang, S.; Helms, J.

    2006-11-24

    The bone marrow is believed to play important roles during fracture healing such as providing progenitor cells for inflammation, matrix remodeling, and cartilage and bone formation. Given the complex nature of bone repair, it remains difficult to distinguish the contributions of various cell types. Here we describe a mouse model based on bone marrow transplantation and genetic labeling to track cells originating from bone marrow during fracture healing. Following lethal irradiation and engraftment of bone marrow expressing the LacZ transgene constitutively, wild type mice underwent tibial fracture. Donor bone marrow-derived cells, which originated from the hematopoietic compartment, did not participate in the chondrogenic and osteogenic lineages during fracture healing. Instead, the donor bone marrow contributed to inflammatory and bone resorbing cells. This model can be exploited in the future to investigate the role of inflammation and matrix remodeling during bone repair, independent from osteogenesis and chondrogenesis.

  5. Stress fracture of the navicular bone. Nine cases in athletes.

    PubMed

    Hulkko, A; Orava, S; Peltokallio, P; Tulikoura, I; Walden, M

    1985-12-01

    Nine cases of stress fractures of the tarsal navicular bone were treated in athletes. The diagnosis was made with radiographs and bone scan within 6 months. Only two patients were treated surgically. The only poor result was seen in a patient in whom the fracture was only explored. PMID:4090953

  6. FRACTURE OF THE CENTRAL TARSAL BONE IN NONRACEHORSES: FOUR CASES.

    PubMed

    Knuchell, Jeannie A; Spriet, Mathieu; Galuppo, Larry D; Katzman, Scott A

    2016-07-01

    Fractures of the central tarsal bone are a rarely recognized cause of acute severe hind limb lameness in nonracehorses. Diagnosis of these fractures can be challenging and little is known about their configuration or outcome. The objectives of this retrospective case series study were to describe the clinical features, imaging findings, and outcomes of fractures of the central tarsal bone in a sample of nonracehorses. Medical records from 2001 to 2014 were searched for cases of central tarsal bone fractures in nonracehorses. All available imaging findings including radiography, ultrasound, computed tomography (CT), and/or nuclear scintigraphy were reviewed. History, clinical presentation, and outcome were collected from the records. Four horses met the inclusion criteria. All had a similar configuration as a simple nondisplaced slab fracture in a dorsomedial to plantarolateral orientation. Initial radiographs failed to reveal the fracture in three of four cases. When additional plantarolateral-dorsomedial oblique radiographic views were obtained, the fracture could be identified in all cases. Fractures of the central tarsal bone seemed to occur in a consistent dorsomedial to plantarolateral orientation in this sample of nonracehorses, which is different from the configuration previously reported in racehorses. While CT can be used for detection and assessment of these fractures, authors propose that radiography can also identify these fractures with the appropriate view. Authors recommend the use of several plantarolateral to dorsomedial radiographic projections at varying degrees of obliquity for horses with a suspected central tarsal bone fracture. PMID:26929208

  7. Bone scanning in the detection of occult fractures

    SciTech Connect

    Batillas, J.; Vasilas, A.; Pizzi, W.F.; Gokcebay, T.

    1981-07-01

    The potential role of bone scanning in the early detection of occult fractures following acute trauma was investigated. Technetium 99m pyrophosphate bone scans were obtained in patients with major clinical findings and negative or equivocal roentgenograms following trauma. Bone scanning facilitated the prompt diagnosis of occult fractures in the hip, knee, wrist, ribs and costochondral junctions, sternum, vertebrae, sacrum, and coccyx. Several illustrative cases are presented. Roentgenographic confirmation occurred following a delay of days to weeks and, in some instances, the roentgenographic findings were subtle and could be easily overlooked. This study demonstrates bone scanning to be invaluable and definitive in the prompt detection of occult fractures.

  8. A direct role of collagen glycation in bone fracture.

    PubMed

    Poundarik, Atharva A; Wu, Ping-Cheng; Evis, Zafer; Sroga, Grazyna E; Ural, Ani; Rubin, Mishaela; Vashishth, Deepak

    2015-12-01

    Non-enzymatic glycation (NEG) is an age-related process accelerated by diseases like diabetes, and causes the accumulation of advanced glycation end-products (AGEs). NEG-mediated modification of bone's organic matrix, principally collagen type-I, has been implicated in impairing skeletal physiology and mechanics. Here, we present evidence, from in vitro and in vivo models, and establish a causal relationship between collagen glycation and alterations in bone fracture at multiple length scales. Through atomic force spectroscopy, we established that NEG impairs collagen's ability to dissipate energy. Mechanical testing of in vitro glycated human bone specimen revealed that AGE accumulation due to NEG dramatically reduces the capacity of organic and mineralized matrix to creep and caused bone to fracture under impact at low levels of strain (3000-5000 μstrain) typically associated with fall. Fracture mechanics tests of NEG modified human cortical bone of varying ages, and their age-matched controls revealed that NEG disrupted microcracking based toughening mechanisms and reduced bone propagation and initiation fracture toughness across all age groups. A comprehensive mechanistic model, based on experimental and modeling data, was developed to explain how NEG and AGEs are causal to, and predictive of bone fragility. Furthermore, fracture mechanics and indentation testing on diabetic mice bones revealed that diabetes mediated NEG severely disrupts bone matrix quality in vivo. Finally, we show that AGEs are predictive of bone quality in aging humans and have diagnostic applications in fracture risk. PMID:26530231

  9. Fracture toughness of steel-fiber-reinforced bone cement.

    PubMed

    Kotha, S P; Li, C; Schmid, S R; Mason, J J

    2004-09-01

    Fractures in the bone-cement mantle (polymethyl methacrylate) have been linked to the failure of cemented total joint prostheses. The heat generated by the curing bone cement has also been implicated in the necrosis of surrounding bone tissue, leading to loosening of the implants. The addition of reinforcements may improve the fracture properties of bone cement and decrease the peak temperatures during curing. This study investigates the changes in the fracture properties and the temperatures generated in the ASTM F451 tests by the addition of 316L stainless steel fibers to bone cement. The influence of filler volume fraction (5-15% by volume) and aspect ratios (19, 46, 57) on the fracture toughness of the acrylic bone cement was assessed. Increasing the volume fraction of the steel fibers resulted in significant increases in the fracture toughness of the steel-fiber-reinforced composite. Fracture-toughness increases of up to 2.63 times the control values were obtained with the use of steel-fiber reinforcements. No clear trend in the fracture toughness was discerned for increasing aspect ratios of the reinforcements. There is a decrease in the peak temperatures reached during the curing of the steel-fiber-reinforced bone cement, though the decrease is too small to be clinically relevant. Large increases in the fatigue life of acrylic bone cement were also obtained by the addition of steel fibers. These results indicate that the use of steel fibers may enhance the durability of cemented joint prostheses. PMID:15293326

  10. Impact and risk factors of post-stroke bone fracture

    PubMed Central

    Huo, Kang; Hashim, Syed I; Yong, Kimberley L Y; Su, Hua; Qu, Qiu-Min

    2016-01-01

    Bone fracture occurs in stroke patients at different times during the recovery phase, prolonging recovery time and increasing medical costs. In this review, we discuss the potential risk factors for post-stroke bone fracture and preventive methods. Most post-stroke bone fractures occur in the lower extremities, indicating fragile bones are a risk factor. Motor changes, including posture, mobility, and balance post-stroke contribute to bone loss and thus increase risk of bone fracture. Bone mineral density is a useful indicator for bone resorption, useful to identify patients at risk of post-stroke bone fracture. Calcium supplementation was previously regarded as a useful treatment during physical rehabilitation. However, recent data suggests calcium supplementation has a negative impact on atherosclerotic conditions. Vitamin D intake may prevent osteoporosis and fractures in patients with stroke. Although drugs such as teriparatide show some benefits in preventing osteoporosis, additional clinical trials are needed to determine the most effective conditions for post-stroke applications. PMID:26929915

  11. Impact and risk factors of post-stroke bone fracture.

    PubMed

    Huo, Kang; Hashim, Syed I; Yong, Kimberley L Y; Su, Hua; Qu, Qiu-Min

    2016-02-20

    Bone fracture occurs in stroke patients at different times during the recovery phase, prolonging recovery time and increasing medical costs. In this review, we discuss the potential risk factors for post-stroke bone fracture and preventive methods. Most post-stroke bone fractures occur in the lower extremities, indicating fragile bones are a risk factor. Motor changes, including posture, mobility, and balance post-stroke contribute to bone loss and thus increase risk of bone fracture. Bone mineral density is a useful indicator for bone resorption, useful to identify patients at risk of post-stroke bone fracture. Calcium supplementation was previously regarded as a useful treatment during physical rehabilitation. However, recent data suggests calcium supplementation has a negative impact on atherosclerotic conditions. Vitamin D intake may prevent osteoporosis and fractures in patients with stroke. Although drugs such as teriparatide show some benefits in preventing osteoporosis, additional clinical trials are needed to determine the most effective conditions for post-stroke applications. PMID:26929915

  12. Probabilistic Risk Assessment for Astronaut Post Flight Bone Fracture

    NASA Technical Reports Server (NTRS)

    Lewandowski, Beth; Myers, Jerry; Licata, Angelo

    2015-01-01

    Introduction: Space flight potentially reduces the loading that bone can resist before fracture. This reduction in bone integrity may result from a combination of factors, the most common reported as reduction in astronaut BMD. Although evaluating the condition of bones continues to be a critical aspect of understanding space flight fracture risk, defining the loading regime, whether on earth, in microgravity, or in reduced gravity on a planetary surface, remains a significant component of estimating the fracture risks to astronauts. This presentation summarizes the concepts, development, and application of NASA's Bone Fracture Risk Module (BFxRM) to understanding pre-, post, and in mission astronaut bone fracture risk. The overview includes an assessment of contributing factors utilized in the BFxRM and illustrates how new information, such as biomechanics of space suit design or better understanding of post flight activities may influence astronaut fracture risk. Opportunities for the bone mineral research community to contribute to future model development are also discussed. Methods: To investigate the conditions in which spaceflight induced changes to bone plays a critical role in post-flight fracture probability, we implement a modified version of the NASA Bone Fracture Risk Model (BFxRM). Modifications included incorporation of variations in physiological characteristics, post-flight recovery rate, and variations in lateral fall conditions within the probabilistic simulation parameter space. The modeled fracture probability estimates for different loading scenarios at preflight and at 0 and 365 days post-flight time periods are compared. Results: For simple lateral side falls, mean post-flight fracture probability is elevated over mean preflight fracture probability due to spaceflight induced BMD loss and is not fully recovered at 365 days post-flight. In the case of more energetic falls, such as from elevated heights or with the addition of lateral movement

  13. Spontaneous Resorption of a Penetrating Orbital Bone Fracture Fragment.

    PubMed

    Campbell, Ashley A; Cunnane, Mary Elizabeth; Dunn, Gavin P; Gray, Stacy Tutt; Lefebvre, Daniel R

    2015-01-01

    The authors describe a 20-year-old man who sustained multiple facial fractures in a high-speed motor vehicle crash, including a bone fragment from a skull base fracture that penetrated the orbital soft tissues superomedially. Serial CT scans documented spontaneous resorption over a 6-month period. While it is known that autologous bone grafts used in craniofacial reconstruction exhibit variable amounts of bone resorption, the complete resorption of an intraorbital fracture fragment has not been documented in the literature. His clinical care and the report of his case were undertaken in a fashion in accordance with the principles of the Health Insurance Portability and Accountability Act regulations. PMID:24833452

  14. Optimisation of composite bone plates for ulnar transverse fractures.

    PubMed

    Chakladar, N D; Harper, L T; Parsons, A J

    2016-04-01

    Metallic bone plates are commonly used for arm bone fractures where conservative treatment (casts) cannot provide adequate support and compression at the fracture site. These plates, made of stainless steel or titanium alloys, tend to shield stress transfer at the fracture site and delay the bone healing rate. This study investigates the feasibility of adopting advanced composite materials to overcome stress shielding effects by optimising the geometry and mechanical properties of the plate to match more closely to the bone. An ulnar transverse fracture is characterised and finite element techniques are employed to investigate the feasibility of a composite-plated fractured bone construct over a stainless steel equivalent. Numerical models of intact and fractured bones are analysed and the mechanical behaviour is found to agree with experimental data. The mechanical properties are tailored to produce an optimised composite plate, offering a 25% reduction in length and a 70% reduction in mass. The optimised design may help to reduce stress shielding and increase bone healing rates. PMID:26875147

  15. Method for improved prediction of bone fracture risk using bone mineral density in structural analysis

    NASA Technical Reports Server (NTRS)

    Cann, Christopher E. (Inventor); Faulkner, Kenneth G. (Inventor)

    1992-01-01

    A non-invasive in-vivo method of analyzing a bone for fracture risk includes obtaining data from the bone such as by computed tomography or projection imaging which data represents a measure of bone material characteristics such as bone mineral density. The distribution of the bone material characteristics is used to generate a finite element method (FEM) mesh from which load capability of the bone can be determined. In determining load capability, the bone is mathematically compressed, and stress, strain force, force/area versus bone material characteristics are determined.

  16. The Value of Radionuclide Bone Imaging in Defining Fresh Fractures Among Osteoporotic Vertebral Compression Fractures.

    PubMed

    Zhao, Quan-Ming; Gu, Xiao-Feng; Liu, Zhong-Tang; Cheng, Li

    2016-05-01

    Vertebral fractures are the most common osteoporotic fractures. To perform percutaneous vertebral body cement augmentation, it is essential to accurately identify the affected vertebrae. The study evaluated the role of radionuclide bone imaging in identifying fresh osteoporotic vertebral compression fractures. A prospective study of 39 patients with acute osteoporotic vertebral compression fractures was carried out. All patients underwent magnetic resonance imaging (MRI) and radionuclide bone imaging to determine if the fractures were fresh, followed by percutaneous kyphoplasty for the fresh fractures. The positive rate on radionuclide bone imaging was 92.1% (82/89), and the positive rate on MRI was 93.3% (83/89), with no statistically significant difference (P > 0.05). Eighty-one vertebrae had the same positive identification by both radionuclide bone imaging and MRI, and 5 of the same vertebrae were diagnosed negative by both techniques. One patient with positive radionuclide bone imaging was negative according to MRI, and 2 patients were entirely positive by MRI but negative by radionuclide bone imaging. A kappa test showed good consistency between the 2 methods for detecting the affected vertebrae (Kappa = 0.751, P < 0.01). Radionuclide bone imaging is as sensitive as MRI in the diagnosis of fresh osteoporotic vertebral compression fracture, making it an effective method for detecting affected vertebrae for percutaneous vertebroplasty. PMID:27159858

  17. Pentoxifylline and electromagnetic field improved bone fracture healing in rats

    PubMed Central

    Atalay, Yusuf; Gunes, Nedim; Guner, Mehmet Dervis; Akpolat, Veysi; Celik, Mustafa Salih; Guner, Rezzan

    2015-01-01

    Background The aim of this study was to evaluate the effects of a phosphodiesterase inhibitor pentoxifylline (PTX), electromagnetic fields (EMFs), and a mixture of both materials on bone fracture healing in a rat model. Materials and methods Eighty male Wistar rats were randomly divided into four groups: Group A, femur fracture model with no treatment; Group B, femur fracture model treated with PTX 50 mg/kg/day intraperitoneal injection; Group C, femur fracture model treated with EMF 1.5±0.2 Mt/50 Hz/6 hours/day; and Group D, femur fracture model treated with PTX 50 mg/kg/day intraperitoneal injection and EMF 1.5±0.2 Mt/50 Hz/6 hours/day. Results Bone fracture healing was significantly better in Group B and Group C compared to Group A (P<0.05), but Group D did not show better bone fracture healing than Group A (P>0.05). Conclusion It can be concluded that both a specific EMF and PTX had a positive effect on bone fracture healing but when used in combination, may not be beneficial. PMID:26388687

  18. Identifying Novel Clinical Surrogates to Assess Human Bone Fracture Toughness.

    PubMed

    Granke, Mathilde; Makowski, Alexander J; Uppuganti, Sasidhar; Does, Mark D; Nyman, Jeffry S

    2015-07-01

    Fracture risk does not solely depend on strength but also on fracture toughness; ie, the ability of bone material to resist crack initiation and propagation. Because resistance to crack growth largely depends on bone properties at the tissue level, including collagen characteristics, current X-ray based assessment tools may not be suitable to identify age-related, disease-related, or treatment-related changes in fracture toughness. To identify useful clinical surrogates that could improve the assessment of fracture resistance, we investigated the potential of (1)H nuclear magnetic resonance spectroscopy (NMR) and reference point indentation (RPI) to explain age-related variance in fracture toughness. Harvested from cadaveric femurs (62 human donors), single-edge notched beam (SENB) specimens of cortical bone underwent fracture toughness testing (R-curve method). NMR-derived bound water showed the strongest correlation with fracture toughness properties (r = 0.63 for crack initiation, r = 0.35 for crack growth, and r = 0.45 for overall fracture toughness; p < 0.01). Multivariate analyses indicated that the age-related decrease in different fracture toughness properties were best explained by a combination of NMR properties including pore water and RPI-derived tissue stiffness with age as a significant covariate (adjusted R(2)  = 53.3%, 23.9%, and 35.2% for crack initiation, crack growth, and overall toughness, respectively; p < 0.001). These findings reflect the existence of many contributors to fracture toughness and emphasize the utility of a multimodal assessment of fracture resistance. Exploring the mechanistic origin of fracture toughness, glycation-mediated nonenzymatic collagen crosslinks and intracortical porosity are possible determinants of bone fracture toughness and could explain the sensitivity of NMR to changes in fracture toughness. Assuming fracture toughness is clinically important to the ability of bone to resist fracture

  19. Identifying novel clinical surrogates to assess human bone fracture toughness

    PubMed Central

    Granke, Mathilde; Makowski, Alexander J; Uppuganti, Sasidhar; Does, Mark D; Nyman, Jeffry S

    2015-01-01

    Fracture risk does not solely depend on strength but also on fracture toughness, i.e. the ability of bone material to resist crack initiation and propagation. Because resistance to crack growth largely depends on bone properties at the tissue level including collagen characteristics, current X-ray based assessment tools may not be suitable to identify age-, disease-, or treatment-related changes in fracture toughness. To identify useful clinical surrogates that could improve the assessment of fracture resistance, we investigated the potential of 1H nuclear magnetic resonance spectroscopy (NMR) and reference point indentation (RPI) to explain age-related variance in fracture toughness. Harvested from cadaveric femurs (62 human donors), single-edge notched beam (SENB) specimens of cortical bone underwent fracture toughness testing (R-curve method). NMR-derived bound water showed the strongest correlation with fracture toughness properties (r=0.63 for crack initiation, r=0.35 for crack growth, and r=0.45 for overall fracture toughness; p<0.01). Multivariate analyses indicated that the age-related decrease in different fracture toughness properties were best explained by a combination of NMR properties including pore water and RPI-derived tissue stiffness with age as a significant covariate (adjusted R2 = 53.3%, 23.9%, and 35.2% for crack initiation, crack growth, and overall toughness, respectively; p<0.001). These findings reflect the existence of many contributors to fracture toughness and emphasize the utility of a multimodal assessment of fracture resistance. Exploring the mechanistic origin of fracture toughness, glycation-mediated, non-enzymatic collagen crosslinks and intra-cortical porosity are possible determinants of bone fracture toughness and could explain the sensitivity of NMR to changes in fracture toughness. Assuming fracture toughness is clinically important to the ability of bone to resist fracture, our results suggest that improvements in fracture

  20. Evaluation of bone surrogates for indirect and direct ballistic fractures.

    PubMed

    Bir, Cynthia; Andrecovich, Chris; DeMaio, Marlene; Dougherty, Paul J

    2016-04-01

    The mechanism of injury for fractures to long bones has been studied for both direct ballistic loading as well as indirect. However, the majority of these studies have been conducted on both post-mortem human subjects (PMHS) and animal surrogates which have constraints in terms of storage, preparation and testing. The identification of a validated bone surrogate for use in forensic, medical and engineering testing would provide the ability to investigate ballistic loading without these constraints. Two specific bone surrogates, Sawbones and Synbone, were evaluated in comparison to PMHS for both direct and indirect ballistic loading. For the direct loading, the mean velocity to produce fracture was 121 ± 19 m/s for the PMHS, which was statistically different from the Sawbones (140 ± 7 m/s) and Synbone (146 ± 3 m/s). The average distance to fracture in the indirect loading was .70 cm for the PMHS. The Synbone had a statistically similar average distance to fracture (.61 cm, p=0.54) however the Sawbones average distance to fracture was statistically different (.41 cm, p<0.05). Fractures patterns were found to be comparable to the PMHS for tests conducted with Synbones, however the input parameters were slightly varied to produce similar results. The fractures patterns with the Sawbones were not found to be as comparable to the PMHS. An ideal bone surrogate for ballistic testing was not identified and future work is warranted. PMID:26867672

  1. Inflammation, bone loss and fracture risk in spondyloarthritis

    PubMed Central

    Briot, Karine; Roux, Christian

    2015-01-01

    Osteoporosis (ie, low bone mineral density) is common in ankylosing spondylitis, related to both systemic inflammation and decreased mobility. Vertebral fracture risk is increased; acute back pain in these patients is not always a flare-up of the disease, as it can be related to bone complications. Intervertebral disc fractures in the ankylosed spine are associated with severe neurological complications. As expected from pathophysiology, treatments effective against inflammation have a positive effect on bone, and prospective open studies have shown that tumour-necrosis-factor blockers can improve bone mineral density at the spine and the hip. There is so far no evidence of a decreased risk of fractures with such treatment. PMID:26509065

  2. The crucial role of neutrophil granulocytes in bone fracture healing.

    PubMed

    Kovtun, A; Bergdolt, S; Wiegner, R; Radermacher, P; Huber-Lang, M; Ignatius, A

    2016-01-01

    Delayed bone fracture healing and the formation of non-unions represent an important clinical problem, particularly in polytrauma patients who suffer from posttraumatic systemic inflammation. However, the underlying pathomechanisms remain unclear. Neutrophil granulocytes are crucial effector cells in the systemic immune response and represent the most abundant immune cell population in the early fracture haematoma. Here we investigated the role of neutrophils in a mouse model of uncomplicated fracture healing and compromised fracture healing induced by an additional thoracic trauma. Twenty four hours before injury, 50 % of the mice were systemically treated with an anti-Ly-6G-antibody to reduce neutrophil numbers. In the isolated fracture model, Ly-6G-Ab treatment significantly increased the concentration of both pro- and anti-inflammatory cytokines, including interleukin (IL)-6 and IL-10, and chemokines, for example, C-X-C motif ligand 1 (CXCL1) and monocyte chemotactic protein-1 (MCP-1), in the fracture haematoma. Monocyte/macrophage recruitment was also significantly enhanced. After 21 d, bone regeneration was considerably impaired as demonstrated by significantly diminished bone content and impaired mechanical properties of the fracture callus. These results indicate that undisturbed neutrophil recruitment and function in the inflammatory phase after fracture is crucial to initiate downstream responses leading to bone regeneration. In the combined trauma model, the reduction of neutrophil numbers ameliorated pulmonary inflammation but did not provoke any significant effect on bone regeneration, suggesting that neutrophils may not play a crucial pathomechanistic role in compromised fracture healing induced by an additional thoracic trauma. PMID:27452963

  3. In Vitro Fracture of Human Cortical Bone: Local Fracture Criteria and Toughening Mechanisms

    SciTech Connect

    Nalla, R; Stolken, J; Kinney, J; Ritchie, R

    2004-08-18

    A micro-mechanistic understanding of bone fracture that encompasses how cracks interact with the underlying microstructure and defines their local failure mode is lacking, despite extensive research on the response of bone to a variety of factors like aging, loading, and/or disease. Micro-mechanical models for fracture incorporating such local failure criteria have been widely developed for metallic and ceramic materials systems; however, few such deliberations have been undertaken for the fracture of bone. In fact, although the fracture event in mineralized tissues such as bone is commonly believed to be locally strain controlled, until recently there has been little experimental evidence to support this widely held belief. In the present study, a series of in vitro experiments involving a double-notch bend test geometry are performed in order to shed further light on the nature of the local cracking events that precede catastrophic fracture in bone and to define their relationship to the microstructure. Specifically, crack-microstructure interactions are examined to determine the salient toughening mechanisms in human cortical bone and to characterize how these may affect the anisotropy in fracture properties. Based on preliminary micro-mechanical models of these processes, in particular crack deflection and uncracked ligament bridging, the relative importance of these toughening mechanisms is established.

  4. Fracture length scales in human cortical bone: the necessity of nonlinear fracture models.

    PubMed

    Yang, Q D; Cox, Brian N; Nalla, Ravi K; Ritchie, R O

    2006-03-01

    Recently published data for fracture in human humeral cortical bone are analyzed using cohesive-zone models to deal with the nonlinear processes of material failure. Such models represent the nonlinear deformation processes involved in fracture by cohesive tractions exerted by the failing material along a fracture process zone, rather than attributing all damage to a process occurring at a single point, as in conventional linear-elastic fracture mechanics (LEFM). The relationship between the tractions and the net displacement discontinuity across the process zone is hypothesized to be a material property for bone. To test this hypothesis, the cohesive law was evaluated by analyzing published load vs. load-point displacement data from one laboratory; the calibrated law was then used to predict similar data taken for a different source of bone using a different specimen geometry in a different laboratory. Further model calculations are presented to illustrate more general characteristics of the nonlinear fracture of bone and to demonstrate in particular that LEFM is not internally consistent for all cases of interest. For example, the fracture toughness of bone deduced via LEFM from test data is not necessarily a material constant, but will take different values for different crack lengths and test configurations. LEFM is valid when the crack is much longer than a certain length scale, representative of the length of the process zone in the cohesive model, which for human cortical bone ranges from 3 to 10mm. Since naturally occurring bones and the specimens used to test them are not much larger than this dimension for most relevant orientations, it is apparent that only nonlinear fracture models can give an internally consistent account of their fracture. The cohesive law is thus a more complete representation of the mechanics of material failure than the single-parameter fracture toughness and may therefore provide a superior measure of bone quality. The analysis of

  5. Bone morphogenetic protein-7 accelerates fracture healing in osteoporotic rats

    PubMed Central

    Diwan, Ashish D; Leong, Anthony; Appleyard, Richard; Bhargav, Divya; Fang, Zhi Ming; Wei, Aiqun

    2013-01-01

    Background: Osteoporosis is characterized by low bone mass, bone fragility and increased susceptibility to fracture. Fracture healing in osteoporosis is delayed and rates of implant failure are high with few biological treatment options available. This study aimed to determine whether a single dose of bone morphogenetic protein-7 (BMP-7) in a collagen/carboxy-methyl cellulose (CMC) composite enhanced fracture healing in an osteoporotic rat model. Materials and Methods: An open femoral midshaft osteotomy was performed in female rats 3 months post-ovarectomy. Rats were randomized to receive either BMP-7 composite (n = 30) or composite alone (n = 30) at the fracture site during surgery. Thereafter calluses were collected on days 12, 20 and 31. Callus cross-sectional area, bone mineral density, biomechanical stiffness and maximum torque, radiographic bony union and histological callus maturity were evaluated at each time point. Results: There were statistically significant increases in bone mineral density and callus cross-section area at all time points in the BMP-7 group as compared to controls and biomechanical readings showed stronger bones at day 31 in the BMP-7 group. Histological and radiographic evaluation indicated significant acceleration of bony union in the BMP-7 group as compared to controls. Conclusion: This study demonstrated that BMP-7 accelerates fracture healing in an oestrogen-deficient environment in a rat femoral fracture healing model to scientific relevance level I. The use of BMP-7 composite could offer orthopedic surgeons an advantage over oestrogen therapy, enhancing osteoporotic fracture healing with a single, locally applied dose at the time of surgery, potentially overcoming delays in healing caused by the osteoporotic state. PMID:24379457

  6. Axial and appendicular bone density predict fractures in older women

    NASA Technical Reports Server (NTRS)

    Black, D. M.; Cummings, S. R.; Genant, H. K.; Nevitt, M. C.; Palermo, L.; Browner, W.

    1992-01-01

    To determine whether measurement of hip and spine bone mass by dual-energy x-ray absorptiometry (DEXA) predicts fractures in women and to compare the predictive value of DEXA with that of single-photon absorptiometry (SPA) of appendicular sites, we prospectively studied 8134 nonblack women age 65 years and older who had both DEXA and SPA measurements of bone mass. A total of 208 nonspine fractures, including 37 wrist fractures, occurred during the follow-up period, which averaged 0.7 years. The risk of fracture was inversely related to bone density at all measurement sites. After adjusting for age, the relative risks per decrease of 1 standard deviation in bone density for the occurrence of any fracture was 1.40 for measurement at the proximal femur (95% confidence interval 1.20-1.63) and 1.35 (1.15-1.58) for measurement at the spine. Results were similar for all regions of the proximal femur as well as SPA measurements at the calcaneus, distal radius, and proximal radius. None of these measurements was a significantly better predictor of fractures than the others. Furthermore, measurement of the distal radius was not a better predictor of wrist fracture (relative risk 1.64: 95% CI 1.13-2.37) than other sites, such as the lumbar spine (RR 1.56; CI 1.07-2.26), the femoral neck (RR 1.65; CI 1.12-2.41), or the calcaneus (RR 1.83; CI 1.26-2.64). We conclude that the inverse relationship between bone mass and risk of fracture in older women is similar for absorptiometric measurements made at the hip, spine, and appendicular sites.

  7. [Bone metabolism and fracture risk in anorexia nervosa].

    PubMed

    Fernández Soto, María Luisa; González Jiménez, Amalia; Varsavsky, Mariela

    2010-07-17

    The prevalence of anorexia nervosa has increased in recent years and a large proportion of patients with this disorder have low bone density at diagnosis and, therefore, an increased risk of early and late fractures. The mechanism of bone loss in anorexia nervosa is not well understood, yet it likely includes hypogonadism, alterations of the GH-IGF-1 axis and hypercortisolism. DEXA is the most effective tool for assessing and monitoring bone density in these patients, and it is important to improve or at least stabilize bone metabolism in those with low bone mass. No agent has yet been proven to be effective in improving bone density. However, sustained weight recovery and menses besides an adequate intake of calcium and vitamin D are recommended to optimize the conditions in which bone mass accrual may occur. PMID:19631350

  8. Fractures

    MedlinePlus

    A fracture is a break, usually in a bone. If the broken bone punctures the skin, it is called an open ... falls, or sports injuries. Other causes are low bone density and osteoporosis, which cause weakening of the ...

  9. Modeling orthotropic elasticity, localized plasticity and fracture in trabecular bone

    NASA Astrophysics Data System (ADS)

    O'Connor, D. T.; Elkhodary, K. I.; Fouad, Y.; Greene, M. S.; Sabet, F. A.; Qian, J.; Zhang, Y.; Liu, W. K.; Jasiuk, I.

    2016-05-01

    This work develops a model for the mechanical response of trabecular bone including plasticity, damage and fracture. It features a resultant lamellar orientation that captures trabecular strut anisotropic elasticity, and introduces asymmetric J2 plasticity with isotropic hardening to capture evolving strut tensile and compressive dissipative properties. A continuum compatibility based damage and fracture criterion is also proposed to model fracture surface generation. We investigated fracture of a trabecular bone network under a compressive load, for which failure modes of both tension and compression were identified at the strut level. The predicted trabecular network response was found to fall within the range of experimental results reported in literature. We also investigated the response of idealized struts under compression, tension and bending using our model. Individual struts were found to exhibit micro-buckling under compression and micro-necking under tension. These instabilities are however masked by the multiplicity and complexity of strut orientations at the trabecular network level.

  10. Modeling orthotropic elasticity, localized plasticity and fracture in trabecular bone

    NASA Astrophysics Data System (ADS)

    O'Connor, D. T.; Elkhodary, K. I.; Fouad, Y.; Greene, M. S.; Sabet, F. A.; Qian, J.; Zhang, Y.; Liu, W. K.; Jasiuk, I.

    2016-09-01

    This work develops a model for the mechanical response of trabecular bone including plasticity, damage and fracture. It features a resultant lamellar orientation that captures trabecular strut anisotropic elasticity, and introduces asymmetric J2 plasticity with isotropic hardening to capture evolving strut tensile and compressive dissipative properties. A continuum compatibility based damage and fracture criterion is also proposed to model fracture surface generation. We investigated fracture of a trabecular bone network under a compressive load, for which failure modes of both tension and compression were identified at the strut level. The predicted trabecular network response was found to fall within the range of experimental results reported in literature. We also investigated the response of idealized struts under compression, tension and bending using our model. Individual struts were found to exhibit micro-buckling under compression and micro-necking under tension. These instabilities are however masked by the multiplicity and complexity of strut orientations at the trabecular network level.

  11. Exercise in youth: High bone mass, large bone size, and low fracture risk in old age.

    PubMed

    Tveit, M; Rosengren, B E; Nilsson, J Å; Karlsson, M K

    2015-08-01

    Physical activity is favorable for peak bone mass but if the skeletal benefits remain and influence fracture risk in old age is debated. In a cross-sectional controlled mixed model design, we compared dual X-ray absorptiometry-derived bone mineral density (BMD) and bone size in 193 active and retired male elite soccer players and 280 controls, with duplicate measurements of the same individual done a mean 5 years apart. To evaluate lifetime fractures, we used a retrospective controlled study design in 397 retired male elite soccer players and 1368 controls. Differences in bone traits were evaluated by Student's t-test and fracture risk assessments by Poisson regression and Cox regression. More than 30 years after retirement from sports, the soccer players had a Z-score for total body BMD of 0.4 (0.1 to 0.6), leg BMD of 0.5 (0.2 to 0.8), and femoral neck area of 0.3 (0.0 to 0.5). The rate ratio for fracture after career end was 0.6 (0.4 to 0.9) and for any fragility fracture 0.4 (0.2 to 0.9). Exercise-associated bone trait benefits are found long term after retirement from sports together with a lower fracture risk. This indicates that physical activity in youth could reduce the burden of fragility fractures. PMID:25109568

  12. Fracture Characterization of Human Cortical Bone Under Mode I Loading.

    PubMed

    Silva, Filipe; de Moura, Marcelo; Dourado, Nuno; Xavier, José; Pereira, Fábio; Morais, José; Dias, Maria; Lourenço, Paulo; Judas, Fernando

    2015-12-01

    A miniaturized version of the double cantilever beam (DCB) test is used to determine the fracture energy in human cortical bone under pure mode I loading. An equivalent crack length based data-reduction scheme is used with remarkable advantages relative to classical methods. Digital image correlation (DIC) technique is employed to determine crack opening displacement at the crack tip being correlated with the evolution of fracture energy. A method is presented to obtain the cohesive law (trapezoidal bilinear softening) mimicking the mechanical behavior observed in bone. Cohesive zone modeling (CZM) (finite-element method) was performed to validate the procedure showing excellent agreement. PMID:26502314

  13. Biglycan modulates angiogenesis and bone formation during fracture healing.

    PubMed

    Berendsen, Agnes D; Pinnow, Emily L; Maeda, Azusa; Brown, Aaron C; McCartney-Francis, Nancy; Kram, Vardit; Owens, Rick T; Robey, Pamela G; Holmbeck, Kenn; de Castro, Luis F; Kilts, Tina M; Young, Marian F

    2014-04-01

    Matrix proteoglycans such as biglycan (Bgn) dominate skeletal tissue and yet its exact role in regulating bone function is still unclear. In this paper we describe the potential role of (Bgn) in the fracture healing process. We hypothesized that Bgn could regulate fracture healing because of previous work showing that it can affect normal bone formation. To test this hypothesis, we created fractures in femurs of 6-week-old male wild type (WT or Bgn+/0) and Bgn-deficient (Bgn-KO or Bgn-/0) mice using a custom-made standardized fracture device, and analyzed the process of healing over time. The formation of a callus around the fracture site was observed at both 7 and 14 days post-fracture in WT and Bgn-deficient mice and immunohistochemistry revealed that Bgn was highly expressed in the fracture callus of WT mice, localizing within woven bone and cartilage. Micro-computed tomography (μCT) analysis of the region surrounding the fracture line showed that the Bgn-deficient mice had a smaller callus than WT mice. Histology of the same region also showed the presence of less cartilage and woven bone in the Bgn-deficient mice compared to WT mice. Picrosirius red staining of the callus visualized under polarized light showed that there was less fibrillar collagen in the Bgn-deficient mice, a finding confirmed by immunohistochemistry using antibodies to type I collagen. Interestingly, real time RT-PCR of the callus at 7 days post-fracture showed a significant decrease in relative vascular endothelial growth factor A (VEGF) gene expression by Bgn-deficient mice as compared to WT. Moreover, VEGF was shown to bind directly to Bgn through a solid-phase binding assay. The inability of Bgn to directly enhance VEGF-induced signaling suggests that Bgn has a unique role in regulating vessel formation, potentially related to VEGF storage or stabilization in the matrix. Taken together, these results suggest that Bgn has a regulatory role in the process of bone formation during

  14. Biglycan modulates angiogenesis and bone formation during fracture healing

    PubMed Central

    Berendsen, Agnes D.; Pinnow, Emily L.; Maeda, Azusa; Brown, Aaron C.; McCartney-Francis, Nancy; Kram, Vardit; Owens, Rick T.; Robey, Pamela G.; Holmbeck, Kenn; de Castro, Luis F.; Kilts, Tina M.; Young, Marian F.

    2014-01-01

    Matrix proteoglycans such as biglycan (Bgn) dominate skeletal tissue and yet its exact role in regulating bone function is still unclear. In this paper we describe the potential role of (Bgn) in the fracture healing process. We hypothesized that Bgn could regulate fracture healing because of previous work showing that it can affect normal bone formation. To test this hypothesis, we created fractures in femurs of 6-week-old male wild type (WT or Bgn+/0) and Bgn-deficient (Bgn-KO or Bgn−/0) mice using a custom-made standardized fracture device, and analyzed the process of healing over time. The formation of a callus around the fracture site was observed at both 7 and 14 days post-fracture in WT and Bgn-deficient mice and immunohistochemistry revealed that Bgn was highly expressed in the fracture callus of WT mice, localizing within woven bone and cartilage. Micro-computed tomography (μCT) analysis of the region surrounding the fracture line showed that the Bgn-deficient mice had a smaller callus than WT mice. Histology of the same region also showed the presence of less cartilage and woven bone in the Bgn-deficient mice compared to WT mice. Picrosirius red staining of the callus visualized under polarized light showed that there was less fibrillar collagen in the Bgn-deficient mice, a finding confirmed by immunohistochemistry using antibodies to type I collagen. Interestingly, real time RT-PCR of the callus at 7 days post-fracture showed a significant decrease in relative vascular endothelial growth factor A (VEGF) gene expression by Bgn-deficient mice as compared to WT. Moreover, VEGF was shown to bind directly to Bgn through a solid-phase binding assay. The inability of Bgn to directly enhance VEGF-induced signaling suggests that Bgn has a unique role in regulating vessel formation, potentially related to VEGF storage or stabilization in the matrix. Taken together, these results suggest that Bgn has a regulatory role in the process of bone formation during

  15. [The changes of bone architecture in atypical femoral fracture].

    PubMed

    Yamamoto, Noriaki; Shimakura, Taketoshi; Takahash, Hideaki

    2013-07-01

    The feature of atypical femoral fracture is stress induced cortical bone reaction. It was considered to be the accumulation of microdamage which come from increasing of mechanical stress by femoral lateral bowing, and the decreased of ability of microdamage repair system. PMID:23811584

  16. Repairing Fractured Bones by Use of Bioabsorbable Composites

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    2006-01-01

    A proposed method of surgical repair of fractured bones would incorporate recent and future advances in the art of composite materials. The composite materials used in this method would be biocompatible and at least partly bioabsorbable: that is, during the healing process following surgery, they would be wholly or at least partly absorbed into the bones and other tissues in which they were implanted. Relative to the traditional method, the proposed method would involve less surgery, pose less of a risk of infection, provide for better transfer of loads across fracture sites, and thereby promote better healing while reducing the need for immobilization by casts and other external devices. One requirement that both the traditional and proposed methods must satisfy is to fix the multiple segments of a broken bone in the correct relative positions. Mechanical fixing techniques used in the traditional method include the use of plates spanning the fracture site and secured to the bone by screws, serving of wire along the bone across the fracture site, insertion of metallic intramedullary rods through the hollow portion of the fractured bone, and/or inserting transverse rods through the bone, muscle, and skin to stabilize the fractured members. After the bone heals, a second surgical operation is needed to remove the mechanical fixture(s). In the proposed method, there would be no need for a second surgical operation. The proposed method is based partly on the observation that in the fabrication of a structural member, it is generally more efficient and reliable to use multiple small fasteners to transfer load across a joint than to use a single or smaller number of larger fasteners, provided that the stress fields of neighboring small fasteners do not overlap or interact. Also, multiple smaller fasteners are more reliable than are larger and fewer fasteners. However, there is a trade-off between structural efficiency and the cost of insertion time and materials. The

  17. 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

  18. Do laying hens with keel bone fractures experience pain?

    PubMed

    Nasr, Mohammed A F; Nicol, Christine J; Murrell, Joanna C

    2012-01-01

    The European ban on battery cages has forced a change towards the use of non-cage or furnished cage systems, but unexpectedly this has been associated with an increased prevalence of keel bone fractures in laying hens. Bone fractures are acutely painful in mammals, but the effect of fractures on bird welfare is unclear. We recently reported that keel bone fractures have an effect on bird mobility. One possible explanation for this is that flying becomes mechanically impaired. However it is also possible that if birds have a capacity to feel pain, then ongoing pain resulting from the fracture could contribute to decreased mobility. The aim was to provide proof of concept that administration of appropriate analgesic drugs improves mobility in birds with keel fracture; thereby contributing to the debate about the capacity of birds to experience pain and whether fractures are associated with pain in laying hens. In hens with keel fractures, butorphanol decreased the latency to land from perches compared with latencies recorded for these hens following saline (mean (SEM) landing time (seconds) birds with keel fractures treated with butorphanol and saline from the 50, 100 and 150 cm perch heights respectively 1.7 (0.3), 2.2 (0.3), p = 0.05, 50 cm; 12.5 (6.6), 16.9 (6.7), p = 0.03, 100 cm; 20.6 (7.4), 26.3 (7.6), p = 0.02 150 cm). Mobility indices were largely unchanged in birds without keel fractures following butorphanol. Critically, butorphanol can be considered analgesic in our study because it improved the ability of birds to perform a complex behaviour that requires both motivation and higher cognitive processing. This is the first study to provide a solid evidential base that birds with keel fractures experience pain, a finding that has significant implications for the welfare of laying hens that are housed in non-cage or furnished caged systems. PMID:22927930

  19. Do Laying Hens with Keel Bone Fractures Experience Pain?

    PubMed Central

    Nasr, Mohammed A. F.; Nicol, Christine J.; Murrell, Joanna C.

    2012-01-01

    The European ban on battery cages has forced a change towards the use of non-cage or furnished cage systems, but unexpectedly this has been associated with an increased prevalence of keel bone fractures in laying hens. Bone fractures are acutely painful in mammals, but the effect of fractures on bird welfare is unclear. We recently reported that keel bone fractures have an effect on bird mobility. One possible explanation for this is that flying becomes mechanically impaired. However it is also possible that if birds have a capacity to feel pain, then ongoing pain resulting from the fracture could contribute to decreased mobility. The aim was to provide proof of concept that administration of appropriate analgesic drugs improves mobility in birds with keel fracture; thereby contributing to the debate about the capacity of birds to experience pain and whether fractures are associated with pain in laying hens. In hens with keel fractures, butorphanol decreased the latency to land from perches compared with latencies recorded for these hens following saline (mean (SEM) landing time (seconds) birds with keel fractures treated with butorphanol and saline from the 50, 100 and 150 cm perch heights respectively 1.7 (0.3), 2.2 (0.3), p = 0.05, 50 cm; 12.5 (6.6), 16.9 (6.7), p = 0.03, 100 cm; 20.6 (7.4), 26.3 (7.6), p = 0.02 150 cm). Mobility indices were largely unchanged in birds without keel fractures following butorphanol. Critically, butorphanol can be considered analgesic in our study because it improved the ability of birds to perform a complex behaviour that requires both motivation and higher cognitive processing. This is the first study to provide a solid evidential base that birds with keel fractures experience pain, a finding that has significant implications for the welfare of laying hens that are housed in non-cage or furnished caged systems. PMID:22927930

  20. Bone fracture in a rat femoral fracture model is associated with the activation of autophagy

    PubMed Central

    ZHOU, QIANKUN; LUO, DEQING; LI, TENG; LIU, ZHIRONG; ZOU, WEITAO; WANG, LEI; LIN, DASHENG; LIAN, KEJIAN

    2015-01-01

    Autophagy, which is a mechanism for the turnover of intracellular molecules and organelles, protects cells during stress responses; however, the role of autophagy in the stages of bone fracture remains to be elucidated. The aim of the present study was to investigate the process of autophagy in bone tissue at different time-points after fracture. A femur fracture model was established in male adult Wistar rats via surgery. The protein expression of microtubule-associated protein II light chain 3 (LC3-II) was analyzed in a femur fracture (experimental) group and a sham-surgery group using immunofluorescence. The protein expression of proliferating cell nuclear antigen (PCNA) was used to investigate the cell proliferation in bone tissue following fracture via immunohistochemical analysis. The correlation between cell proliferation and autophagy was analyzed using linear regression. LC3-II protein was constitutively expressed in the sham-surgery group; however, compared with the expression in the sham-surgery group, the LC3-II expression in the experimental group was significantly increased at each time-point (P<0.05). Similarly, immunohistochemistry revealed that the number of PCNA-positive cells in each section was significantly increased following fracture injury (P<0.01). A comparison of the LC3-II- and PCNA-positive rates in the experimental group rats at each time-point revealed a linear correlation (R2=0.43, P<0.01). In conclusion, surgically induced fracture in rats is associated with an increase in LC3-II and PCNA protein expression during the initial stages of fracture injury, and a correlation exists between the expression of the two proteins. These results suggest that potential treatment aimed at improving fracture healing should target the process of autophagy. PMID:26640535

  1. Shear deformation and fracture of human cortical bone.

    PubMed

    Tang, Tengteng; Ebacher, Vincent; Cripton, Peter; Guy, Pierre; McKay, Heather; Wang, Rizhi

    2015-02-01

    Bone can be viewed as a nano-fibrous composite with complex hierarchical structures. Its deformation and fracture behaviors depend on both the local structure and the type of stress applied. In contrast to the extensive studies on bone fracture under compression and tension, there is a lack of knowledge on the fracture process under shear, a stress state often exists in hip fracture. This study investigated the mechanical behavior of human cortical bone under shear, with the focus on the relation between the fracture pattern and the microstructure. Iosipescu shear tests were performed on notched rectangular bar specimens made from human cortical bone. They were prepared at different angles (i.e. 0°, 30°, 60° and 90°) with respect to the long axis of the femoral shaft. The results showed that human cortical bone behaved as an anisotropic material under shear with the highest shear strength (~50MPa) obtained when shearing perpendicular to the Haversian systems or secondary osteons. Digital image correlation (DIC) analysis found that shear strain concentration bands had a close association with long bone axis with an average deviation of 11.8° to 18.5°. The fracture pattern was also greatly affected by the structure with the crack path generally following the direction of the long axes of osteons. More importantly, we observed unique peripheral arc-shaped microcracks within osteons, using laser scanning confocal microscopy (LSCM). They were generally long cracks that developed within a lamella without crossing the boundaries. This microcracking pattern clearly differed from that created under either compressive or tensile stress: these arc-shaped microcracks tended to be located away from the Haversian canals in early-stage damaged osteons, with ~70% developing in the outer third osteonal wall. Further study by second harmonic generation (SHG) and two-photon excitation fluorescence (TPEF) microscopy revealed a strong influence of the organization of collagen

  2. Role of mathematical modeling in bone fracture healing

    PubMed Central

    Pivonka, Peter; Dunstan, Colin R

    2012-01-01

    Bone fracture healing is a complex physiological process commonly described by a four-phase model consisting of an inflammatory phase, two repair phases with soft callus formation followed by hard callus formation, and a remodeling phase, or more recently by an anabolic/catabolic model. Data from humans and animal models have demonstrated crucial environmental conditions for optimal fracture healing, including the mechanical environment, blood supply and availability of mesenchymal stem cells. Fracture healing spans multiple length and time scales, making it difficult to know precisely which factors and/or phases to manipulate in order to obtain optimal fracture-repair outcomes. Deformations resulting from physiological loading or fracture fixation at the organ scale are sensed at the cellular scale by cells inside the fracture callus. These deformations together with autocrine and paracrine signals determine cellular differentiation, proliferation and migration. The local repair activities lead to new bone formation and stabilization of the fracture. Although experimental data are available at different spatial and temporal scales, it is not clear how these data can be linked to provide a holistic view of fracture healing. Mathematical modeling is a powerful tool to quantify conceptual models and to establish the missing links between experimental data obtained at different scales. The objective of this review is to introduce mathematical modeling to readers who are not familiar with this methodology and to demonstrate that once validated, such models can be used for hypothesis testing and to assist in clinical treatment as will be shown for the example of atrophic nonunions. PMID:24228159

  3. Aging and Fracture of Human Cortical Bone and Tooth Dentin

    SciTech Connect

    Ager, Joel; Koester, Kurt J.; Ager III, Joel W.; Ritchie, Robert O.

    2008-05-07

    Mineralized tissues, such as bone and tooth dentin, serve as structural materials in the human body and, as such, have evolved to resist fracture. In assessing their quantitative fracture resistance or toughness, it is important to distinguish between intrinsic toughening mechanisms which function ahead of the crack tip, such as plasticity in metals, and extrinsic mechanisms which function primarily behind the tip, such as crack bridging in ceramics. Bone and dentin derive their resistance to fracture principally from extrinsic toughening mechanisms which have their origins in the hierarchical microstructure of these mineralized tissues. Experimentally, quantification of these toughening mechanisms requires a crack-growth resistance approach, which can be achieved by measuring the crack-driving force, e.g., the stress intensity, as a function of crack extension ("R-curve approach"). Here this methodology is used to study of the effect of aging on the fracture properties of human cortical bone and human dentin in order to discern the microstructural origins of toughness in these materials.

  4. Fractures

    MedlinePlus

    ... commonly happen because of car accidents, falls, or sports injuries. Other causes are low bone density and osteoporosis, which cause weakening of the bones. Overuse can cause stress fractures, which are very small cracks in the ...

  5. Characteristics of bone turnover in the long bone metaphysis fractured patients with normal or low Bone Mineral Density (BMD).

    PubMed

    Wölfl, Christoph; Schweppenhäuser, Daniela; Gühring, Thorsten; Takur, Caner; Höner, Bernd; Kneser, Ulrich; Grützner, Paul Alfred; Kolios, Leila

    2014-01-01

    The incidence of osteoporotic fractures increases as our population ages. Until now, the exact biochemical processes that occur during the healing of metaphyseal fractures remain unclear. Diagnostic instruments that allow a dynamic insight into the fracture healing process are as yet unavailable. In the present matched pair analysis, we study the time course of the osteoanabolic markers bone specific alkaline phosphatase (BAP) and transforming growth factor β1 (TGFβ1), as well as the osteocatabolic markers crosslinked C-telopeptide of type-I-collagen (β-CTX) and serum band 5 tartrate-resistant acid phosphatase (TRAP5b), during the healing of fractures that have a low level of bone mineral density (BMD) compared with fractures that have a normal BMD. Between March 2007 and February 2009, 30 patients aged older than 50 years who suffered a metaphyseal fracture were included in our study. BMDs were verified by dual energy Xray absorptiometry (DXEA) scans. The levels of BTMs were examined over an 8-week period. Osteoanabolic BAP levels in those with low levels of BMD were significantly different from the BAP levels in those with normal BMD. BAP levels in the former group increased constantly, whereas the latter group showed an initial strong decrease in BAP followed by slowly rising values. Osteocatabolic β-CTX increased in the bone of the normal BMD group constantly, whereas these levels decreased significantly in the bone of the group with low BMD from the first week. TRAP5b was significantly reduced in the low level BMD group. With this work, we conduct first insights into the molecular biology of the fracture healing process in patients with low levels of BMD that explains the mechanism of its fracture healing. The results may be one reason for the reduced healing qualities in bones with low BMD. PMID:24788647

  6. The Photodynamic Bone Stabilization System: a minimally invasive, percutaneous intramedullary polymeric osteosynthesis for simple and complex long bone fractures

    PubMed Central

    Vegt, Paul; Muir, Jeffrey M; Block, Jon E

    2014-01-01

    The treatment of osteoporotic long bone fractures is difficult due to diminished bone density and compromised biomechanical integrity. The majority of osteoporotic long bone fractures occur in the metaphyseal region, which poses additional problems for surgical repair due to increased intramedullary volume. Treatment with internal fixation using intramedullary nails or plating is associated with poor clinical outcomes in this patient population. Subsequent fractures and complications such as screw pull-out necessitate additional interventions, prolonging recovery and increasing health care costs. The Photodynamic Bone Stabilization System (PBSS) is a minimally invasive surgical technique that allows clinicians to repair bone fractures using a light-curable polymer contained within an inflatable balloon catheter, offering a new treatment option for osteoporotic long bone fractures. The unique polymer compound and catheter application provides a customizable solution for long bone fractures that produces internal stability while maintaining bone length, rotational alignment, and postsurgical mobility. The PBSS has been utilized in a case series of 41 fractures in 33 patients suffering osteoporotic long bone fractures. The initial results indicate that the use of the light-cured polymeric rod for this patient population provides excellent fixation and stability in compromised bone, with a superior complication profile. This paper describes the clinical uses, procedural details, indications for use, and the initial clinical findings of the PBSS. PMID:25540600

  7. Outcome of unstable fractures of metacarpal and phalangeal bones treated by bone tie

    PubMed Central

    Kamath, Jagannath B; Jayasheelan, Nikil; Savur, Amaranth; Mathews, Rejith

    2016-01-01

    Background: Unstable fractures of the metacarpal and phalangeal bones of the hand need surgical stabilization which should be rigid enough for early active mobilization. Conventional methods of open reduction and stabilization in the form of composite fixation or screws with or without plates have served the purpose but can be definitely improvised addressing both biological and mechanical principles of fixation. Materials and Methods: 34 patients (29 males and 5 females) with an average age of 32 years (range 10–64 years) with unstable fractures of the metacarpal and phalangeal bones of hand who were treated with the modified bone tie between June 2009 and June 2013 were included in this study. 42 fractures, involving the 31 metacarpals and 11 phalanges were included. We have not used this technique in fractures involving the terminal phalanges. Thirty nine of the fractures were treated with K-wires along with the modified bone tie, whereas the other two cases were treated with modified bone tie alone and in one case the bone tie has been used along with the external fixator. The nature of injuries were Road Traffic Accident (n = 24), domestic/industrial injuries (n = 8) and blast (n = 2) injuries. Etiology was crush (n = 24), blunt (n = 7) and incised (n = 3) injuries, respectively. Twenty seven patients were involved with single fractures (either metacarpal or the phalanges), 6 patients had two fractures (both metacarpals or phalanges or one each of metacarpal and phalanx), and 1 patient had three fractures in this study. Dominant hand was involved in 14 patients (40%). Results: We achieved excellent to good results in 83% of 42 fractures within an average period of 10 weeks. Postoperative grip strength of 85% was achieved with in an average period of 12 weeks. Twenty six (20 metacarpals and 6 phalanges) of the 42 fractures regained >85% of the total active movements (TAMs) compared to the contralateral side were considered excellent results. All patients were

  8. BIOMATERIAL IMPLANTS IN BONE FRACTURES PRODUCED IN RATS FIBULAS

    PubMed Central

    Shirane, Henrique Yassuhiro; Oda, Diogo Yochizumi; Pinheiro, Thiago Cerizza; Cunha, Marcelo Rodrigues da

    2015-01-01

    To evaluate the importance of collagen and hydroxyapatite in the regeneration of fractures experimentally induced in the fibulas of rats. Method: 15 rats were used. These were subjected to surgery to remove a fragment from the fibula. This site then received a graft consisting of a silicone tubes filled with hydroxyapatite and collagen. Results: Little bone neoformation occurred inside the tubes filled with the biomaterials. There was more neoformation in the tubes with collagen. Conclusion: The biomaterials used demonstrated biocompatibility and osteoconductive capacity that was capable of stimulating osteogenesis, even in bones with secondary mechanical and morphological functions such as the fibula of rats. PMID:27047813

  9. Bone graft substitutes and bone morphogenetic proteins for osteoporotic fractures: what is the evidence?

    PubMed

    Van Lieshout, Esther M M; Alt, Volker

    2016-01-01

    Despite improvements in implants and surgical techniques, osteoporotic fractures remain challenging to treat. Among other major risk factors, decreased expression of morphogenetic proteins has been identified for impaired fracture healing in osteoporosis. Bone grafts or bone graft substitutes are often used for stabilizing the implant and for providing a scaffold for ingrowth of new bone. Both synthetic and naturally occurring biomaterials are available. Products generally contain hydroxyapatite, tricalcium phosphate, dicalcium phosphate, calcium phosphate cement, calcium sulfate (plaster of Paris), or combinations of the above. Products have been used for the treatment of osteoporotic fractures of the proximal humerus, distal radius, vertebra, hip, and tibia plateau. Although there is generally consensus that screw augmentation increased the biomechanical properties and implant stability, the results of using these products for void filling are not unequivocal. In osteoporotic patients, Bone Morphogenetic Proteins (BMPs) have the potential impact to improve fracture healing by augmenting the impaired molecular and cellular mechanisms. However, the clinical evidence on the use of BMPs in patients with osteoporotic fractures is poor as there are no published clinical trials, case series or case studies. Even pre-clinical literature on in vitro and in vivo data is weak as most articles focus on the beneficial role for BMPs for restoration of the underlying pathophysiological factors of osteoporosis but do not look at the specific effects on osteoporotic fracture healing. Limited data on animal experiments suggest stimulation of fracture healing in ovariectomized rats by the use of BMPs. In conclusion, there is only limited data on the clinical relevance and optimal indications for the use of bone graft substitute materials and BMPs on the treatment of osteoporotic fractures despite the clinical benefits of these materials in other clinical indications. Given the

  10. The Comparison of Bone Scan and MRI in Osteoporotic Compression Fractures

    PubMed Central

    Kim, Jung-Hoon; Kim, Jong-In; Jang, Bo-Hoon; Seo, Jung-Gook

    2010-01-01

    Study Design Retrospective study. Purpose To estimate the usefulness of bone scan and magnetic resonance imaging (MRI) for the diagnosis of new fracture in osteoporotic vertebral fractures. Overview of Literature The diagnosis of new fractrure in osteoporotic vertebral fractures requires simple X-ray and supplementary studies. Methods We analyzed 87 vertebrae in 44 patients, who diagnosed with osteoporotic vertebral fractures using bone scan and MRI within 2 months interval between August 2001 and July 2008. We compared hot uptakes in bone scan with MRI findings such as new fractures, old fractures and degenerative lesions. Results Hot uptakes in bone scan was matched to 48 new fractures, 26 old fractures and 13 degenerative lesions in MRI findings. It was 55% of concordance between hot uptakes in bone scan and new fractures in MRI. The rate of new vertebral fractures confirmed by MRI according to 1 level hot uptakes in bone scan was 96%, 2 levels was 50% and 3 more levels was 36%. Conclusions The diagnosis of new fracture in osteoporotic vertebral fractures requires simple X-ray and supplementary studies such as bone scan and MRI. We recommend more careful interpretation in multiple osteoporotic vertebral fracture patients about hot uptake lesions of bone scan. PMID:21165311

  11. Insulin-like growth factor 1, glycation and bone fragility: implications for fracture resistance of bone.

    PubMed

    Sroga, Grażyna E; Wu, Ping-Cheng; Vashishth, Deepak

    2015-01-01

    Despite our extensive knowledge of insulin-like growth factor 1 (IGF1) action on the growing skeleton, its role in skeletal homeostasis during aging and age-related development of certain diseases is still unclear. Advanced glycation end products (AGEs) derived from glucose are implicated in osteoporosis and a number of diabetic complications. We hypothesized that because in humans and rodents IGF1 stimulates uptake of glucose (a glycation substrate) from the bloodstream in a dose-dependent manner, the decline of IGF1 could be associated with the accumulation of glycation products and the decreasing resistance of bone to fracture. To test the aforementioned hypotheses, we used human tibial posterior cortex bone samples to perform biochemical (measurement of IGF1, fluorescent AGEs and pentosidine (PEN) contents) and mechanical tests (crack initiation and propagation using compact tension specimens). Our results for the first time show a significant, age-independent association between the levels of IGF1 and AGEs. Furthermore, AGEs (fAGEs, PEN) predict propensity of bone to fracture (initiation and propagation) independently of age in human cortical bone. Based on these results we propose a model of IGF1-based regulation of bone fracture. Because IGF1 level increases postnatally up to the juvenile developmental phase and decreases thereafter with aging, we propose that IGF1 may play a protective role in young skeleton and its age-related decline leads to bone fragility and an increased fracture risk. Our results may also have important implications for current understanding of osteoporosis- and diabetes-related bone fragility as well as in the development of new diagnostic tools to screen for fragile bones. PMID:25629402

  12. Insulin-Like Growth Factor 1, Glycation and Bone Fragility: Implications for Fracture Resistance of Bone

    PubMed Central

    Sroga, Grażyna E.; Wu, Ping-Cheng; Vashishth, Deepak

    2015-01-01

    Despite our extensive knowledge of insulin-like growth factor 1 (IGF1) action on the growing skeleton, its role in skeletal homeostasis during aging and age-related development of certain diseases is still unclear. Advanced glycation end products (AGEs) derived from glucose are implicated in osteoporosis and a number of diabetic complications. We hypothesized that because in humans and rodents IGF1 stimulates uptake of glucose (a glycation substrate) from the bloodstream in a dose-dependent manner, the decline of IGF1 could be associated with the accumulation of glycation products and the decreasing resistance of bone to fracture. To test the aforementioned hypotheses, we used human tibial posterior cortex bone samples to perform biochemical (measurement of IGF1, fluorescent AGEs and pentosidine (PEN) contents) and mechanical tests (crack initiation and propagation using compact tension specimens). Our results for the first time show a significant, age-independent association between the levels of IGF1 and AGEs. Furthermore, AGEs (fAGEs, PEN) predict propensity of bone to fracture (initiation and propagation) independently of age in human cortical bone. Based on these results we propose a model of IGF1-based regulation of bone fracture. Because IGF1 level increases postnatally up to the juvenile developmental phase and decreases thereafter with aging, we propose that IGF1 may play a protective role in young skeleton and its age-related decline leads to bone fragility and an increased fracture risk. Our results may also have important implications for current understanding of osteoporosis- and diabetes-related bone fragility as well as in the development of new diagnostic tools to screen for fragile bones. PMID:25629402

  13. Influence of Fatigue Loading and Bone Turnover on Bone Strength and Pattern of Experimental Fractures of the Tibia in Mice.

    PubMed

    Bonnet, Nicolas; Gerbaix, Maude; Ominsky, Michael; Ammann, Patrick; Kostenuik, Paul J; Ferrari, Serge L

    2016-07-01

    Bone fragility depends on bone mass, structure, and material properties, including damage. The relationship between bone turnover, fatigue damage, and the pattern and location of fractures, however, remains poorly understood. We examined these factors and their integrated effects on fracture strength and patterns in tibia. Adult male mice received RANKL (2 mg/kg/day), OPG-Fc (5 mg/kg 2×/week), or vehicle (Veh) 2 days prior to fatigue loading of one tibia by in vivo axial compression, with treatments continuing up to 28 more days. One day post fatigue, crack density was similarly increased in fatigued tibiae from all treatment groups. After 28 days, the RANKL group exhibited reduced bone mass and increased crack density, resulting in reduced bone strength, while the OPG-Fc group had greater bone mass and bone strength. Injury repair altered the pattern and location of fractures created by ex vivo destructive testing, with fractures occurring more proximally and obliquely relative to non-fatigued tibia. A similar pattern was observed in both non-fatigued and fatigued tibia of RANKL. In contrast, OPG-Fc prevented this fatigue-related shift in fracture pattern by maintaining fractures more distal and transverse. Correlation analysis showed that bone strength was predominantly determined by aBMD with minor contributions from structure and intrinsic strength as measured by nanoindentation and cracks density. In contrast, fracture location was predicted equally by aBMD, crack density and intrinsic modulus. The data suggest that not only bone strength but also the fracture pattern depends on previous damage and the effects of bone turnover on bone mass and structure. These observations may be relevant to further understand the mechanisms contributing to fracture pattern in long bone with different levels of bone remodeling, including atypical femur fracture. PMID:26945756

  14. Unusual Foreign Bone Fragment in Femoral Open Fracture

    PubMed Central

    Sadoni, Hanon; Arti, Hamidreza

    2016-01-01

    Introduction: Femoral shaft fracture is one of the typical bone fractures due to high energy trauma and may occur as an open fracture. Some foreign materials may enter the fracture site such as sand, cloth particles and so on. Case Presentation: A 28-year-old motorcycle riding military member and his collaborator were received in the hospital because of multiple traumas due to a fall in a hollow during a surveillance mission. His collaborator died because of head trauma and multiple severe open fractures. When fixing the patients femoral fracture, a large femoral butterfly fragment was removed from the patient’s thigh as a foreign segment. The patient’s femur was fixed with a plate and screws. No femoral defect was detected during surgery or post-operative X-rays and CT scan. The removed segment was not a part of the patient’s femur. Conclusions: Surgical and post-surgical findings showed that this segment was not related to the patient’s femur. The foreign segment may have belonged to the other victim of this trauma.

  15. A removable hybrid robot system for long bone fracture reduction.

    PubMed

    Wang, Tianmiao; Li, Changsheng; Hu, Lei; Tang, Peifu; Zhang, Lihai; Du, Hailong; Luan, Sheng; Wang, Lifeng; Tan, Yiming; Peng, Cheng

    2014-01-01

    In traditional long bone fracture reduction surgery, there are some drawbacks such as low accuracy, high radiation for surgeons and a risk of infection. To overcome these disadvantages, a removable hybrid robot system is developed, which integrates a removable series-parallel mechanism with a motor-double cylinder (MDC) driven mode. This paper describes the mechanism in detail, analyses the principle and the method of the fracture reduction, presents the surgical procedure, and verifies the reduction accuracy by experiments with bone models. The results are shown as follows. The mean deviations of the axial displacement and lateral displacement are 1.60mm and 1.26 mm respectively. The standard deviations are 0.69 mm and 0.30 mm. The mean deviations of the side angle and turn inward are 2.06° and 2.22° respectively. The standard deviations are 0.50° and 0.99°. This minimally invasive robot features high accuracy and zero radiation for surgeons, and is able to conduct fracture reduction for long bones. PMID:24211933

  16. [Multiple long bone fractures in a child with pycnodysostosis. A case report].

    PubMed

    Rojas, Paula I; Niklitschek, Nathia E; Sepúlveda, Matías F

    2016-06-01

    Fractures are an important entity to consider in pediatric patients. There are certain diseases in which bones fracture with a minimal trauma. Pycnodysostosis is an autosomal recessive unusual type of cráneo metaphyseal dysplasia, that presents frequently as fracture in a pathological bone. A 9 year old caucasian female, diagnosed with pycnodysostosis, was admitted with a right femur fracture as a result of a low energy trauma. Radiographic studies showed bilateral femur fractures, proximal fracture and non-union in antecurvatum of the left tibia. Pycnodysostosis is a rare disease, generally diagnosed at an early age by growth restriction, frequent fractures or fractures with low energy trauma. Therapy alternatives are limited, and no permanent cure has been developed. If a patient has dysmorphic facial features and fractures in a pathological bone, it is important to suspect bone dysplasia, such as pycnodysostosis and its differential diagnoses. PMID:27164353

  17. Effects of Statins on Bone Mineral Density and Fracture Risk

    PubMed Central

    Wang, Zongze; Li, Ying; Zhou, Fengxin; Piao, Zhe; Hao, Jian

    2016-01-01

    Abstract Although observational studies have identified the protective effect of statins on bone health, the effects remain controversial in randomized controlled trials (RCTs). We conducted a meta-analysis of RCTs to evaluate the effects of statins on bone mineral density (BMD) and fracture risk among adults. We searched electronic databases of Medline, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) and conducted a bibliography review to identify articles published until May, 2015. Studies included in this meta-analysis should be randomized controlled trials conducted in adults, using statins in the intervention group. Information on changes in BMD or odds ratio, relative risk or hazard ratio (HR) for fracture risk with the corresponding 95% confidence interval (CI) was provided. Two investigators independently reviewed the title or abstract, further reviewed the full-texts and extracted information on study characteristics and study outcomes. Net change estimates of BMD and pooled HR of fracture risk comparing the intervention group with the control group were estimated across trials using random-effects models. Of the relevant 334 citations, 7 trials (including 27,900 randomized participants in total) meeting the eligibility criteria were included. Of the 7 trials, 5 were conducted to assess the association of statins use with BMD change and 2 with fracture risk. Compared with the control group, statins use was associated with significant increase in BMD of 0.03 g/cm2 (95% CI: 0.006, 0.053; I2 = 99.2%; P < 0.001), but null association with fracture risk, with the pooled HR of 1.00 (95% CI: 0.87, 1.15; I2 = 0; P = 0.396). Sensitivity analyses revealed that the associations were consistent and robust. The effect of statins use on bone health among subpopulation could not be identified due to limited number of trials. These findings provide evidence that statins could be used to increase BMD other than decreasing fracture

  18. A new WNT on the bone: WNT16, cortical bone thickness, porosity and fractures

    PubMed Central

    Gori, Francesca; Lerner, Ulf; Ohlsson, Claes; Baron, Roland

    2015-01-01

    The last decade has provided abundant data implicating the WNT pathway in bone development and in the regulation of skeletal homeostasis. Rare human mutations together with gain- and loss-of-function approaches in mice have clearly demonstrated that disrupted regulation of this pathway leads to altered bone mass. In addition to these rare human and mice mutations, large population-based genome-wide association studies (GWASs) have identified single-nucleotide polymorphisms in ∼60 loci strongly associated with variations in bone mineral density (BMD) at different skeletal sites. Among the loci/genes identified by BMD GWAS, components of the WNT signaling pathway are numerous and have been shown to contribute to skeletal development and homeostasis. Within the components of WNT signaling, the gene coding for WNT16, one of the 19 WNT ligands of the human genome, has been found strongly associated with specific bone traits such as cortical bone thickness, cortical porosity and fracture risk. Recently, the first functional characterization of Wnt16 has confirmed the critical role of Wnt16 in the regulation of cortical bone mass and bone strength in mice. These reports have extended our understanding of Wnt16 function in bone homeostasis and have not only confirmed the unique association of Wnt16 with cortical bone and fracture susceptibility, as suggested by GWAS in human populations, but have also provided novel insights into the biology of this WNT ligand and the mechanism(s) by which it regulates cortical but not trabecular bone homeostasis. Most interestingly, Wnt16 appears to be a strong anti-resorptive soluble factor acting on both osteoblasts and osteoclast precursors. PMID:25987984

  19. A 12-month prospective study of the relationship between stress fractures and bone turnover in athletes.

    PubMed

    Bennell, K L; Malcolm, S A; Brukner, P D; Green, R M; Hopper, J L; Wark, J D; Ebeling, P R

    1998-07-01

    Bone remodeling may be involved in the pathogenesis of stress fractures in athletes. We conducted a 12-month prospective study to evaluate bone turnover in 46 female and 49 male track and field athletes aged 17-26 years (mean age 20.3; SD 2.0) 20 of whom developed a stress fracture. Baseline levels of bone turnover were evaluated in all athletes and monthly bone turnover levels were evaluated in a subset consisting of the 20 athletes who sustained a stress fracture and a matched comparison group who did not sustain a stress fracture. Bone formation was assessed using serum osteocalcin (OC) measured by human immunoradiometric assay and bone resorption by urinary excretion of pyridinium cross-links (Pyr and D-Pyr); high performance liquid chromatography and N-telopeptides of type 1 collagen (NTx) using ELISA assay. Athletes who developed stress fractures had similar baseline levels of bone turnover compared with their nonstress fracture counterparts (P > 0.10). Results of serial measurements showed no differences in average levels of Pyr, D-Pyr, or OC in those who developed stress fractures (P = 0.10) compared with the control group. In the athletes with stress fractures, there was also no difference in bone turnover levels prior to or following the onset of bony pain. Our results show that single and multiple measurements of bone turnover are not clinically useful in predicting the likelihood of stress fractures in athletes. Furthermore, there were no consistent temporal changes in bone turnover associated with stress fracture development. However, our results do not negate the possible pathogenetic role of local changes in bone remodeling at stress fracture sites, given the high biological variability of bone turnover markers and the fact that levels of bone turnover reflect the integration of all bone remodeling throughout the skeleton. PMID:9632851

  20. Anti-IL-20 monoclonal antibody promotes bone fracture healing through regulating IL-20-mediated osteoblastogenesis

    PubMed Central

    Hsu, Yu-Hsiang; Chiu, Yi-Shu; Chen, Wei-Yu; Huang, Kuo-Yuan; Jou, I-Ming; Wu, Po-Tin; Wu, Chih-Hsing; Chang, Ming-Shi

    2016-01-01

    Bone loss and skeletal fragility in bone fracture are caused by an imbalance in bone remodeling. The current challenge in bone fracture healing is to promote osteoblastogenesis and bone formation. We aimed to explore the role of IL-20 in osteoblastogenesis, osteoblast differentiation and bone fracture. Serum IL-20 was significantly correlated with serum sclerostin in patients with bone fracture. In a mouse model, anti-IL-20 monoclonal antibody (mAb) 7E increased bone formation during fracture healing. In vitro, IL-20 inhibited osteoblastogenesis by upregulating sclerostin, and downregulating osterix (OSX), RUNX2, and osteoprotegerin (OPG). IL-20R1 deficiency attenuated IL-20-mediated inhibition of osteoblast differentiation and maturation and reduced the healing time after a bone fracture. We conclude that IL-20 affects bone formation and downregulates osteoblastogenesis by modulating sclerostin, OSX, RUNX2, and OPG on osteoblasts. Our results demonstrated that IL-20 is involved in osteoregulation and anti-IL-20 mAb is a potential therapeutic for treating bone fracture or metabolic bone diseases. PMID:27075747

  1. Trabecular bone fracture healing simulation with finite element analysis and fuzzy logic.

    PubMed

    Shefelbine, Sandra J; Augat, Peter; Claes, Lutz; Simon, Ulrich

    2005-12-01

    Trabecular bone fractures heal through intramembraneous ossification. This process differs from diaphyseal fracture healing in that the trabecular marrow provides a rich vascular supply to the healing bone, there is very little callus formation, woven bone forms directly without a cartilage intermediary, and the woven bone is remodelled to form trabecular bone. Previous studies have used numerical methods to simulate diaphyseal fracture healing or bone remodelling, however not trabecular fracture healing, which involves both tissue differentiation and trabecular formation. The objective of this study was to determine if intramembraneous bone formation and remodelling during trabecular bone fracture healing could be simulated using the same mechanobiological principles as those proposed for diaphyseal fracture healing. Using finite element analysis and the fuzzy logic for diaphyseal healing, the model simulated formation of woven bone in the fracture gap and subsequent remodelling of the bone to form trabecular bone. We also demonstrated that the trabecular structure is dependent on the applied loading conditions. A single model that can simulate bone healing and remodelling may prove to be a useful tool in predicting musculoskeletal tissue differentiation in different vascular and mechanical environments. PMID:16214492

  2. Automatic retrieval of bone fracture knowledge using natural language processing.

    PubMed

    Do, Bao H; Wu, Andrew S; Maley, Joan; Biswal, Sandip

    2013-08-01

    Natural language processing (NLP) techniques to extract data from unstructured text into formal computer representations are valuable for creating robust, scalable methods to mine data in medical documents and radiology reports. As voice recognition (VR) becomes more prevalent in radiology practice, there is opportunity for implementing NLP in real time for decision-support applications such as context-aware information retrieval. For example, as the radiologist dictates a report, an NLP algorithm can extract concepts from the text and retrieve relevant classification or diagnosis criteria or calculate disease probability. NLP can work in parallel with VR to potentially facilitate evidence-based reporting (for example, automatically retrieving the Bosniak classification when the radiologist describes a kidney cyst). For these reasons, we developed and validated an NLP system which extracts fracture and anatomy concepts from unstructured text and retrieves relevant bone fracture knowledge. We implement our NLP in an HTML5 web application to demonstrate a proof-of-concept feedback NLP system which retrieves bone fracture knowledge in real time. PMID:23053906

  3. A Rare Combination Open Fracture Dislocation of Elbow with Open Fracture both Bones Forearm with Radial Nerve Palsy

    PubMed Central

    Shivanna, Deepak; Aski, Bahubali; Manjunath, Dayanand; Bhatnagar, Abhinav

    2014-01-01

    Introduction: The injury pattern of open fracture dislocation of elbow with fracture both bones forearm with radial nerve injury is very rare. Very few reports are there in literature related to this kind of injury. However this combination is first of its kind. This rare injury needs special attention by early intervention and biological fixation to achieve good results. Case Report: A 22 year old female presented to us with history of road traffic accident. On evaluation patient had combination of open fracture dislocation of elbow with open diaphyseal fracture of both forearm bones with radial nerve palsy. The patient was treated in emergency and followed for 2 years. Conclusion: Open fracture dislocation of elbow is a rare entity. Our case additionally had open fracture both the bones forearm with radial nerve palsy. Early intervention and biological fixation with minimal invasion gives good results in terms of range of movements and patient satisfaction. PMID:27298951

  4. Results of autogenous trephine biopsy needle bone grafting in fractures of radius and ulna.

    PubMed

    Lakhey, S; Shrestha, B P; Pradhan, R L; Pandey, B; Rijal, K P

    2005-01-01

    Cortico-Cancellous bone graft harvested from the anterior iliac crest by the conventional open method is associated with more morbidity and is more time consuming as compared to the percutaneous method using trephine biopsy needle. The aim of the study was to determine whether cancellous bone graft harvested from anterior iliac crest using trephine biopsy needle consistently achieved bone union in comminuted fractures and fractures of more than 3 weeks duration of radius and ulna and also to determine the morbidity at the donor site. Autogenous cancellous bone graft was harvested percutaneously from 28 iliac crests in 16 patients and applied at fracture sites of 30 forearm bones using a 4mm trephine biopsy needle after the fractures had been fixed with plate and screws. The patients were followed up regularly upto 6 to 9 months post - operatively in the OPD to determine the union status of the fractured bones and the morbidity at the donor site. 29 of the 30 fractures of the forearm bones united without any problems. The shaft of a trephine got bent during the harvesting procedure at the beginning of the study due to improper technique. Cancellous bone graft harvested from the anterior iliac crest results in predictable good union results in comminuted fractures of forearm bones and also fractures presenting after 3 weeks of injury. It is also an easier and quicker way of harvesting bone graft and is associated with lesser morbidity and earlier recovery as compared to conventional open method. PMID:16554860

  5. Bone growth stimulators. New tools for treating bone loss and mending fractures.

    PubMed

    Whitfield, James F; Morley, Paul; Willick, Gordon E

    2002-01-01

    In the new millennium, humans will be traveling to Mars and eventually beyond with skeletons that respond to microgravity by self-destructing. Meanwhile in Earth's aging populations growing numbers of men and many more women are suffering from crippling bone loss. During the first decade after menopause all women suffer an accelerating loss of bone, which in some of them is severe enough to result in "spontaneous" crushing of vertebrae and fracturing of hips by ordinary body movements. This is osteoporosis, which all too often requires prolonged and expensive care, the physical and mental stress of which may even kill the patient. Osteoporosis in postmenopausal women is caused by the loss of estrogen. The slower development of osteoporosis in aging men is also due at least in part to a loss of the estrogen made in ever smaller amounts in bone cells from the declining level of circulating testosterone and is needed for bone maintenance as it is in women. The loss of estrogen increases the generation, longevity, and activity of bone-resorbing osteoclasts. The destructive osteoclast surge can be blocked by estrogens and selective estrogen receptor modulators (SERMs) as well as antiosteoclast agents such as bisphosphonates and calcitonin. But these agents stimulate only a limited amount of bone growth as the unaffected osteoblasts fill in the holes that were dug by the now suppressed osteoclasts. They do not stimulate osteoblasts to make bone--they are antiresorptives not bone anabolic agents. (However, certain estrogen analogs and bisphosphates may stimulate bone growth to some extent by lengthening osteoblast working lives.) To grow new bone and restore bone strength lost in space and on Earth we must know what controls bone growth and destruction. Here we discuss the newest bone controllers and how they might operate. These include leptin from adipocytes and osteoblasts and the statins that are widely used to reduce blood cholesterol and cardiovascular damage. But

  6. New TASER injuries: lacrimal canaliculus laceration and ethmoid bone fracture.

    PubMed

    de Runz, A; Minetti, C; Brix, M; Simon, E

    2014-06-01

    The TASER is a non-lethal conducted electrical weapon intended to incapacitate a person. The growing use of the TASER has resulted in an increased risk of injuries, including those to the face. We report a case of lacrimal canaliculus laceration and ethmoid bone fracture caused by an extra penetration (XP) TASER X26 dart. A 35-year-old was subdued with a TASER head shot; the probe was discharged into the left medial canthus without causing any ocular lesions. A computed tomography scan revealed the probe to be embedded in the left nasolacrimal duct and showed a displaced ethmoid fracture. The barbed dart had sectioned the inferior lacrimal canaliculus without electrifying the lesion. This case expands the knowledge of injuries that may occur as a result of the use of this device and the management of peri-ocular TASER injuries. PMID:24491847

  7. The biomechanical effect of bone quality and fracture topography on locking plate fixation in periprosthetic femoral fractures.

    PubMed

    Leonidou, Andreas; Moazen, Mehran; Lepetsos, Panagiotis; Graham, Simon M; Macheras, George A; Tsiridis, Eleftherios

    2015-02-01

    Optimal management of periprosthetic femoral fractures (PFF) around a well fixed prosthesis (Vancouver B1) remains controversial as adequate fixation needs to be achieved without compromising the stability of the prosthesis. The aim of this study was to highlight the effect of bone quality i.e. canal thickness ratio (CTR), and fracture topography i.e. fracture angle and its position in relation to the stem, on the biomechanics of a locking plate for a Vancouver B1 fracture. A previously corroborated simplified finite element model of a femur with a cemented total hip replacement stem was used in this study. Canal thickness ratio (CTR) and fracture topography were altered in several models and the effect of these variations on the von Mises stress on the locking plate as well as the fracture displacement was studied. Increasing the CTR led to reduction of the von Mises stress on the locking plate as well as the fracture movement. In respect to the fracture angle with the medial cortex, it was shown that acute angles resulted in lower von Mises stress on the plate as opposed to obtuse angles. Furthermore, acute fracture angles resulted in lower fracture displacement compared to the other fractures considered here. Fractures around the tip of the stem had the same biomechanical effect on the locking plate. However, fractures more distal to the stem led to subsequent increase of stress, strain, and fracture displacement. Results highlight that in good bone quality and acute fracture angles, single locking plate fixation is perhaps an appropriate management method. On the contrary, for poor bone quality and obtuse fracture angles alternative management methods might be required as the fixation might be under higher risk of failure. Clinical studies for the management of PFF are required to further support our findings. PMID:25467710

  8. Depressive Symptoms, Bone Loss, and Fractures in Postmenopausal Women

    PubMed Central

    Scholes, Delia; Brunner, Robert L.; Robbins, John; Reed, Susan D.; Newton, Katherine M.; Melville, Jennifer L.; LaCroix, Andrea Z.

    2008-01-01

    Background Osteoporosis and depression may be associated through common physiologic systems or risk factors. Objective To assess the associations between depressive symptoms (Burnam’s scale) or antidepressant use and bone outcomes. Design Prospective cohort study. Participants A total of 93,676 postmenopausal women (50 to 79 years old) enrolled in the Women’s Health Initiative Observational Study. Measurements Self-reported fractures (n = 14,982) (hip [adjudicated], spine, wrist, and “other”). Analyses included 82,410 women with complete information followed on average for 7.4 years. Bone mineral density (BMD) of the hip (n = 4539), spine (n = 4417), and whole body (n = 4502) was measured at baseline and 3 years in women enrolled at 3 densitometry study sites. Results Overall, there were no statistically significant associations between depressive symptoms or antidepressant therapy and 3-year change in BMD. In a subset of women not using antidepressants, there was a significant difference in whole-body BMD change between women with and without depressive symptoms (P = .05). Depressive symptoms (hazard ratio [HR] 1.08; 95% CI = 1.02 to 1.14) and antidepressant therapy (HR = 1.22; CI = 1.15 to 1.30) independently increased risk of any fracture, the majority of which occurred at “other” anatomic sites. Antidepressant therapy increased the risk of spine fracture (HR = 1.36; CI = 1.14 to 1.63). No associations were observed between depressive symptoms or antidepressant therapy and hip or wrist fracture. Conclusion In this study of postmenopausal women, average age 64, we observed minimal association between depressive symptoms and 3-year changes in either BMD or fracture risk. Antidepressant use was not associated with changes in BMD, but was associated with increased risk of fractures at the spine and “other ” anatomic sites. PMID:18286345

  9. Sphenoid Sinus and Sphenoid Bone Fractures in Patients with Craniomaxillofacial Trauma

    PubMed Central

    Cantini Ardila, Jorge Ernesto; Mendoza, Miguel Ángel Rivera; Ortega, Viviana Gómez

    2013-01-01

    Background and Purpose Sphenoid bone fractures and sphenoid sinus fractures have a high morbidity due to its association with high-energy trauma. The purpose of this study is to describe individuals with traumatic injuries from different mechanisms and attempt to determine if there is any relationship between various isolated or combined fractures of facial skeleton and sphenoid bone and sphenoid sinus fractures. Methods We retrospectively studied hospital charts of all patients who reported to the trauma center at Hospital de San José with facial fractures from December 2009 to August 2011. All patients were evaluated by computed tomography scan and classified into low-, medium-, and high-energy trauma fractures, according to the classification described by Manson. Design This is a retrospective descriptive study. Results The study data were collected as part of retrospective analysis. A total of 250 patients reported to the trauma center of the study hospital with facial trauma. Thirty-eight patients were excluded. A total of 212 patients had facial fractures; 33 had a combination of sphenoid sinus and sphenoid bone fractures, and facial fractures were identified within this group (15.5%). Gender predilection was seen to favor males (77.3%) more than females (22.7%). The mean age of the patients was 37 years. Orbital fractures (78.8%) and maxillary fractures (57.5%) were found more commonly associated with sphenoid sinus and sphenoid bone fractures. Conclusions High-energy trauma is more frequently associated with sphenoid fractures when compared with medium- and low-energy trauma. There is a correlation between facial fractures and sphenoid sinus and sphenoid bone fractures. A more exhaustive multicentric case-control study with a larger sample and additional parameters will be essential to reach definite conclusions regarding the spectrum of fractures of the sphenoid bone associated with facial fractures. PMID:24436756

  10. Treatment of nonunions of long bone fractures with shock waves

    NASA Astrophysics Data System (ADS)

    Wang, Ching-Jen

    2003-10-01

    A prospective clinical study investigated the effectiveness of shock waves in the treatment of 72 patients with 72 nonunions of long bone fractures (41 femurs, 19 tibias, 7 humeri, 1 radius, 3 ulnas and 1 metatarsal). The doses of shock waves were 6000 impulses at 28 kV for the femur and tibia, 3000 impulses at 28 kV for the humerus, 2000 impulses at 24 kV for the radius and ulna, and 1000 impulses at 20 kV for the metatarsal. The results of treatment were assessed clinically, and fracture healing was assessed with plain x-rays and tomography. The rate of bony union was 40% at 3 months, 60.9% at 6 months and 80% at 12 months followup. Shock wave treatment was most successful in hypertrophic nonunions and nonunions with a defect and was least effective in atrophic nonunions. There were no systemic complications or device-related problems. Local complications included petechiae and hematoma formation that resolved spontaneously. In the author's experience, the results of the shock wave treatment were similar to the results of surgical treatment for chronic nonunions with no surgical risks. Shock wave treatment is a safe and effective alternative method in the treatment of chronic nonunions of long bones.

  11. Spinal cord injury-related bone impairment and fractures: an update on epidemiology and physiopathological mechanisms.

    PubMed

    Dionyssiotis, Y

    2011-09-01

    A sudden loss of motor function in segments of the spinal cord results in immobilisation and is complicated by bone loss and fractures in areas below the level of injury. Despite the acceptance of osteoporosis and fractures as two major public health problems, in people with spinal cord injuries, the mechanisms are not adequately investigated. Multiple risk factors for bone loss and fractures are present in this disabled population. This review is an update on the epidemiology and physiopathological mechanisms in spinal cord injury-related bone impairment and fractures. PMID:21885901

  12. Bone Transport for Limb Reconstruction Following Severe Tibial Fractures.

    PubMed

    Fürmetz, Julian; Soo, Chris; Behrendt, Wolf; Thaller, Peter H; Siekmann, Holger; Böhme, Jörg; Josten, Christoph

    2016-03-21

    A common treatment of tibial defects especially after infections is bone transport via external fixation. We compare complications and outcomes of 25 patients treated with a typical Ilizarov frame or a hybrid system for bone reconstruction of the tibia. Average follow up was 5.1 years. Particular interest was paid to the following criteria: injury type, comorbidities, development of osteitis and outcome of the different therapies. The reason for segmental resection was a second or third grade open tibia fractures in 24 cases and in one case an infection after plate osteosynthesis. Average age of the patients was 41 years (range 19 to 65 years) and average defect size 6.6 cm (range 3.0 to 13.4 cm). After a mean time of 113 days 23 tibial defects were reconstructed, so we calculated an average healing index of 44.2 days/cm. Two patients with major comorbidities needed a below knee amputation. The presence of osteitis led to a more complicated course of therapy. In the follow up patients with an Ilizarov frame had better results than patients with hybrid systems. Bone transport using external fixation is suitable for larger defect reconstruction. With significant comorbidities, however, a primary amputation or other methods must be considered. PMID:27114814

  13. Bone Transport for Limb Reconstruction Following Severe Tibial Fractures

    PubMed Central

    Fürmetz, Julian; Soo, Chris; Behrendt, Wolf; Thaller, Peter H.; Siekmann, Holger; Böhme, Jörg; Josten, Christoph

    2016-01-01

    A common treatment of tibial defects especially after infections is bone transport via external fixation. We compare complications and outcomes of 25 patients treated with a typical Ilizarov frame or a hybrid system for bone reconstruction of the tibia. Average follow up was 5.1 years. Particular interest was paid to the following criteria: injury type, comorbidities, development of osteitis and outcome of the different therapies. The reason for segmental resection was a second or third grade open tibia fractures in 24 cases and in one case an infection after plate osteosynthesis. Average age of the patients was 41 years (range 19 to 65 years) and average defect size 6.6 cm (range 3.0 to 13.4 cm). After a mean time of 113 days 23 tibial defects were reconstructed, so we calculated an average healing index of 44.2 days/cm. Two patients with major comorbidities needed a below knee amputation. The presence of osteitis led to a more complicated course of therapy. In the follow up patients with an Ilizarov frame had better results than patients with hybrid systems. Bone transport using external fixation is suitable for larger defect reconstruction. With significant comorbidities, however, a primary amputation or other methods must be considered. PMID:27114814

  14. Development and validation of a predictive bone fracture risk model for astronauts.

    PubMed

    Nelson, Emily S; Lewandowski, Beth; Licata, Angelo; Myers, Jerry G

    2009-11-01

    There are still many unknowns in the physiological response of human beings to space, but compelling evidence indicates that accelerated bone loss will be a consequence of long-duration spaceflight. Lacking phenomenological data on fracture risk in space, we have developed a predictive tool based on biomechanical and bone loading models at any gravitational level of interest. The tool is a statistical model that forecasts fracture risk, bounds the associated uncertainties, and performs sensitivity analysis. In this paper, we focused on events that represent severe consequences for an exploration mission, specifically that of spinal fracture resulting from a routine task (lifting a heavy object up to 60 kg), or a spinal, femoral or wrist fracture due to an accidental fall or an intentional jump from 1 to 2 m. We validated the biomechanical and bone fracture models against terrestrial studies of ground reaction forces, skeletal loading, fracture risk, and fracture incidence. Finally, we predicted fracture risk associated with reference missions to the moon and Mars that represented crew activities on the surface. Fracture was much more likely on Mars due to compromised bone integrity. No statistically significant gender-dependent differences emerged. Wrist fracture was the most likely type of fracture, followed by spinal and hip fracture. PMID:19707874

  15. Bone Repair on Fractures Treated with Osteosynthesis, ir Laser, Bone Graft and Guided Bone Regeneration: Histomorfometric Study

    NASA Astrophysics Data System (ADS)

    dos Santos Aciole, Jouber Mateus; dos Santos Aciole, Gilberth Tadeu; Soares, Luiz Guilherme Pinheiro; Barbosa, Artur Felipe Santos; Santos, Jean Nunes; Pinheiro, Antonio Luiz Barbosa

    2011-08-01

    The aim of this study was to evaluate, through the analysis of histomorfometric, the repair of complete tibial fracture in rabbits fixed with osteosynthesis, treated or not with infrared laser light (λ780 nm, 50 mW, CW) associated or not to the use of hydroxyapatite and guided bone regeneration (GBR). Surgical fractures were created, under general anesthesia (Ketamina 0,4 ml/Kg IP and Xilazina 0,2 ml/Kg IP), on the dorsum of 15 Oryctolagus rabbits that were divided into 5 groups and maintained on individual cages, at day/night cycle, fed with solid laboratory pelted diet and had water ad libidum. On groups II, III, IV and V the fracture was fixed with wire osteosynthesis. Animals of groups III and V were grafted with hydroxyapatite and GBR technique used. Animals of groups IV and V were irradiated at every other day during two weeks (16 J/cm2, 4×4 J/cm2). Observation time was that of 30 days. After animal death (overdose of general anesthetics) the specimes were routinely processed to wax and underwent histological analysis by light microscopy. The histomorfometric analysis showed an increased bone neoformation, increased collagen deposition, less reabsorption and inflammation when laser was associated to the HATCP. It is concluded that IR laser light was able to accelerate fracture healing and the association with HATCP and GBR resulted on increased deposition of CHA.

  16. Bone Fracture Pre-Ischemic Stroke Exacerbates Ischemic Cerebral Injury in Mice

    PubMed Central

    Zou, Dingquan; Zhan, Lei; Li, Zhengxi; Zhu, Wan; Su, Hua

    2016-01-01

    Ischemic stroke is a devastating complication of bone fracture. Bone fracture shortly after stroke enhances stroke injury by augmenting inflammation. We hypothesize that bone fracture shortly before ischemic stroke also exacerbates ischemic cerebral injury. Tibia fracture was performed 6 or 24 hours before permanent middle cerebral artery occlusion (pMCAO) on C57BL/6J mice or Ccr2RFP/+Cx3cr1GFP/+ mice that have the RFP gene knocked into one allele of Ccr2 gene and GFP gene knocked into one allele of Cx3cr1 gene. Behavior was tested 3 days after pMCAO. Infarct volume, the number of CD68+ cells, apoptotic neurons, bone marrow-derived macrophages (RFP+), and microgila (GFP+) in the peri-infarct region were quantified. Compared to mice subjected to pMCAO only, bone fracture 6 or 24 hours before pMCAO increased behavioral deficits, the infarct volume, and the number of CD68+ cells and apoptotic neurons in the peri-infarct area. Both bone marrow-derived macrophages (CCR2+) and microglia (CX3CR1+) increased in the peri-infarct regions of mice subjected to bone fracture before pMCAO compared to stroke-only mice. The mice subjected to bone fracture 6 hours before pMCAO had more severe injury than mice that had bone fracture 24 hours before pMCAO. Our data showed that bone fracture shortly before stroke also increases neuroinflammation and exacerbates ischemic cerebral injury. Our findings suggest that inhibition of neuroinflammation or management of stroke risk factors before major bone surgery would be beneficial for patients who are likely to suffer from stroke. PMID:27089041

  17. Sensitivities of biomechanical assessment methods for fracture healing of long bones.

    PubMed

    Chen, G; Wu, F Y; Zhang, J Q; Zhong, G Q; Liu, F

    2015-07-01

    There is a controversy as to whether the biomechanical methods are feasible to assess fracture healing of long bones. This paper investigated the sensitivities of two biomechanical methods, torsion and bending, for assessing fracture healing of long bones; both a simplified beam model and finite element model of an artificial femur were employed. The results demonstrated that, in the initial healing stage, the whole-bone stiffness of the fractured bone is extremely sensitive to the variation of the callus stiffness at the fracture site; when the shear (or Young's) modulus of the callus reaches 15% that of the intact bone, the whole-bone stiffness rises up to 90% that of the intact bone. After that, the whole-bone torsional (or bending) stiffness increases slowly; it becomes less sensitive to the variation of the callus stiffness. These results imply that the whole-bone stiffness is of limited reliability to assess the healing quality particular at late stages of the healing process. The simplified model in this paper provided a theoretical framework to explain why the whole-bone stiffness is insensitive to the healing process of fractured long bones in the late stage of healing. The conclusions obtained from the simplified model were verified with the finite element simulations of the artificial femur. PMID:25983068

  18. Integrity of the osteocyte bone cell network in osteoporotic fracture: Implications for mechanical load adaptation

    NASA Astrophysics Data System (ADS)

    Kuliwaba, J. S.; Truong, L.; Codrington, J. D.; Fazzalari, N. L.

    2010-06-01

    The human skeleton has the ability to modify its material composition and structure to accommodate loads through adaptive modelling and remodelling. The osteocyte cell network is now considered to be central to the regulation of skeletal homeostasis; however, very little is known of the integrity of the osteocyte cell network in osteoporotic fragility fracture. This study was designed to characterise osteocyte morphology, the extent of osteocyte cell apoptosis and expression of sclerostin protein (a negative regulator of bone formation) in trabecular bone from the intertrochanteric region of the proximal femur, for postmenopausal women with fragility hip fracture compared to age-matched women who had not sustained fragility fracture. Osteocyte morphology (osteocyte, empty lacunar, and total lacunar densities) and the degree of osteocyte apoptosis (percent caspase-3 positive osteocyte lacunae) were similar between the fracture patients and non-fracture women. The fragility hip fracture patients had a lower proportion of sclerostin-positive osteocyte lacunae in comparison to sclerostin-negative osteocyte lacunae, in contrast to similar percent sclerostin-positive/sclerostin-negative lacunae for non-fracture women. The unexpected finding of decreased sclerostin expression in trabecular bone osteocytes from fracture cases may be indicative of elevated bone turnover and under-mineralisation, characteristic of postmenopausal osteoporosis. Further, altered osteocytic expression of sclerostin may be involved in the mechano-responsiveness of bone. Optimal function of the osteocyte cell network is likely to be a critical determinant of bone strength, acting via mechanical load adaptation, and thus contributing to osteoporotic fracture risk.

  19. Trabecular Plate Loss and Deteriorating Elastic Modulus of Femoral Trabecular Bone in Intertrochanteric Hip Fractures

    PubMed Central

    Wang, Ji; Zhou, Bin; Parkinson, Ian; Thomas, C. David L.; Clement, John G.; Fazzalari, Nick; Guo, X. Edward

    2013-01-01

    Osteoporotic hip fracture is associated with significant trabecular bone loss, which is typically characterized as low bone density by dual-energy X-ray absorptiometry (DXA) and altered microstructure by micro-computed tomography (μCT). Emerging morphological analysis techniques, e.g. individual trabecula segmentation (ITS), can provide additional insights into changes in plate-like and rod-like trabeculae, two major microstructural types serving different roles in determining bone strength. Using ITS, we evaluated trabecular microstructure of intertrochanteric bone cores obtained from 23 patients undergoing hip replacement surgery for intertrochanteric fracture and 22 cadaveric controls. Micro-finite element (μFE) analyses were performed to further understand how the abnormalities seen by ITS might translate into effects on bone strength. ITS analyses revealed that, near fracture site, plate-like trabeculae were seriously depleted in fracture patients, but trabecular rod volume was maintained. Besides, decreased plate area and rod length were observed in fracture patients. Fracture patients also showed decreased elastic moduli and shear moduli of trabecular bone. These results provided evidence that in intertrochanteric hip fracture, preferential loss of plate-like trabeculae led to more rod-like microstructure and deteriorated mechanical competence adjacent to the fracture site, which increased our understanding of the biomechanical pathogenesis of hip fracture in osteoporosis. PMID:26273512

  20. Association of microstructural and mechanical properties of cancellous bone and their fracture risk assessment tool scores

    PubMed Central

    Wu, Dengke; Li, Xin; Tao, Cheng; Dai, Ruchun; Ni, Jiangdong; Liao, Eryuan

    2015-01-01

    This study is to investigate the association between fracture probabilities determined by using the fracture risk assessment tool (FRAX) and the microstructure and mechanical properties of femoral bone trabecula in osteoporosis (OP) and osteoarthritis (OA) patients with hip replacements. By using FRAX, we evaluated fracture risks of the 102 patients with bone replacements. Using micro CT scanning, we obtained the analysis parameters of microstructural properties of cancellous bone. Through morphometric observations, fatigue tests and compression tests, we obtained parameters of mechanical properties of cancellous bones. Relevant Pearson analysis was performed to investigate the association between the fracture probability and the microstructure and mechanical properties of femoral bone trabecula in patients. Fifteen risk factors in FRAX were compared between OP and OA patients. FRAX hip fracture risk score and major osteoporotic in OP and OA patients were significantly different. FRAX was associated with tissue bone mineral density and volumetric bone mineral density. Our study suggests that the probabilities of major osteoporotic and hip fracture using FRAX is associated with bone mass but not with micro bone quality. PMID:26064297

  1. Relating crack-tip deformation to mineralization and fracture resistance in human femur cortical bone.

    PubMed

    Chan, Kwai S; Chan, Candace K; Nicolella, Daniel P

    2009-09-01

    The risk of bone fracture increases with age because of a variety of factors that include, among others, decreasing bone quantity and quality. Despite recent advances, the roles of bone microstructure and trace mineralization in the fracture process are not well understood. In this study, we utilize a combination of in-situ fracture toughness testing, digital strain mapping, and X-ray photoelectron spectroscopy techniques to characterize the near-tip strain field, fracture toughness, and chemical elements on the fracture surface of bone specimens from donors of two ages (48-year-old and 78-year-old females). We show that age-related embrittlement of bone fracture is associated with higher near-tip strains by lamellar shear and crack deflection at lamellar interfaces in the young bone and their absence in the old bone. The different near-tip deformation behaviors may be associated with the presence of Si and Zn in the young bone but more Ca and P and the lack of Si and Zn in the old bone. PMID:19497396

  2. Association of microstructural and mechanical properties of cancellous bone and their fracture risk assessment tool scores.

    PubMed

    Wu, Dengke; Li, Xin; Tao, Cheng; Dai, Ruchun; Ni, Jiangdong; Liao, Eryuan

    2015-01-01

    This study is to investigate the association between fracture probabilities determined by using the fracture risk assessment tool (FRAX) and the microstructure and mechanical properties of femoral bone trabecula in osteoporosis (OP) and osteoarthritis (OA) patients with hip replacements. By using FRAX, we evaluated fracture risks of the 102 patients with bone replacements. Using micro CT scanning, we obtained the analysis parameters of microstructural properties of cancellous bone. Through morphometric observations, fatigue tests and compression tests, we obtained parameters of mechanical properties of cancellous bones. Relevant Pearson analysis was performed to investigate the association between the fracture probability and the microstructure and mechanical properties of femoral bone trabecula in patients. Fifteen risk factors in FRAX were compared between OP and OA patients. FRAX hip fracture risk score and major osteoporotic in OP and OA patients were significantly different. FRAX was associated with tissue bone mineral density and volumetric bone mineral density. Our study suggests that the probabilities of major osteoporotic and hip fracture using FRAX is associated with bone mass but not with micro bone quality. PMID:26064297

  3. The fracture mechanics of human bone: influence of disease and treatment.

    PubMed

    Zimmermann, Elizabeth A; Busse, Björn; Ritchie, Robert O

    2015-01-01

    Aging and bone diseases are associated with increased fracture risk. It is therefore pertinent to seek an understanding of the origins of such disease-related deterioration in bone's mechanical properties. The mechanical integrity of bone derives from its hierarchical structure, which in healthy tissue is able to resist complex physiological loading patterns and tolerate damage. Indeed, the mechanisms through which bone derives its mechanical properties make fracture mechanics an ideal framework to study bone's mechanical resistance, where crack-growth resistance curves give a measure of the intrinsic resistance to the initiation of cracks and the extrinsic resistance to the growth of cracks. Recent research on healthy cortical bone has demonstrated how this hierarchical structure can develop intrinsic toughness at the collagen fibril scale mainly through sliding and sacrificial bonding mechanisms that promote plasticity. Furthermore, the bone-matrix structure develops extrinsic toughness at much larger micrometer length-scales, where the structural features are large enough to resist crack growth through crack-tip shielding mechanisms. Although healthy bone tissue can generally resist physiological loading environments, certain conditions such as aging and disease can significantly increase fracture risk. In simple terms, the reduced mechanical integrity originates from alterations to the hierarchical structure. Here, we review how human cortical bone resists fracture in healthy bone and how changes to the bone structure due to aging, osteoporosis, vitamin D deficiency and Paget's disease can affect the mechanical integrity of bone tissue. PMID:26380080

  4. Nose fracture

    MedlinePlus

    Fracture of the nose; Broken nose; Nasal fracture; Nasal bone fracture; Nasal septal fracture ... A fractured nose is the most common fracture of the face. It ... with other fractures of the face. Sometimes a blunt injury can ...

  5. Can Deterministic Mechanical Size Effects Contribute to Fracture and Microdamage Accumulation in Trabecular Bone?

    PubMed Central

    Siegmund, Thomas; Allen, Matthew R.; Burr, David B.

    2010-01-01

    Failure of bone under monotonic and cyclic loading is related to the bone mineral density, the quality of the bone matrix and the evolution of microcracks. The theory of linear elastic fracture mechanics has commonly been applied to describe fracture in bone. Evidence is presented that bone failure can be described through a non-linear theory of fracture. Thereby, deterministic size effects are introduced. Concepts of a non-linear theory are applied to discern how the interaction among bone matrix constituents (collagen and mineral), microcrack characteristics, and trabecular architecture can create distinctively differences in the fracture resistance at the bone tissue level. The nonlinear model is applied to interpret pre-clinical data concerning the effects of anti-osteoporotic agents on bone properties. The results show that bisphosphonate (BP) treatments that suppress bone remodeling will change trabecular bone in ways such that the size of the failure process zone relative to the trabecular thickness is reduced. Selective estrogen receptor modulators (SERMs) that suppress bone remodeling will change trabecular bone in ways such that the size of the failure process zone relative to the trabecular thickness is increased. The consequences of these changes are reflected in bone mechanical response and predictions are consistent with experimental observations in the animal model which show that BP treatment is associated with more brittle fracture and microcracks without altering the average length of the cracks, whereas SERM treatments lead to a more ductile fracture and mainly increase crack length with a smaller increase in microcrack density. The model suggests that BPs may be more effective in cases in which bone mass is very low, whereas SERMS may be more effective when milder osteoporotic symptoms are present. PMID:20398678

  6. [Undislocated fracture of cuneiform I bone complicated by language barrier].

    PubMed

    Lang, C F; Greipel, J M

    2013-12-01

    A 30-year-old non-German speaking patient suffered an ankle sprain while playing beach volleyball. Conventional radiography did not reveal any fractures. The patient was treated with a Geisha cast for immobilization and relief and was also informed about pain-dependent weight bearing using an illustrated information sheet. In the course of the healing process the patient consulted the orthopedic department a second time. During a third visit he left before consultation as he felt that the waiting time was too long. Because he disagreed with the treatment he visited an orthopedist who ordered a magnetic resonance imaging (MRI) scan of the patient’s foot. The MRI scan revealed an undislocated fracture of the cuneiform I bone. A control scan was conducted 2 months later and complex regional pain syndrome (CRPS) was diagnosed. The orthopedist ordered treatment based on a therapy with a VacoPed® orthesis. When there was no improvement in the healing process the patient sued the orthopedic surgeon for medical malpractice due to incorrect load and subsequent pain for € 40,000. All courts up to the Federal Court of Germany dismissed the case as no expert witnesses could find any errors in treatment. The court held that the medical information of the non-German speaking patient was sufficient against the defendant’s arguments. It is, however, noteworthy that the burden of proof for sufficient medical information of a patient is always placed on the treating physician. PMID:24121317

  7. Pathological fractures of the proximal femur due to solitary bone cyst: classification, methods of treatment.

    PubMed

    Miu, A

    2015-01-01

    Fractures are a very important issue in a child's orthopedic pathology. Neglected a good amount of time, being considered "not too serious", or "rare", having better and faster healing methods and not leaving sequels, like in the case of adults, a child's fractures remain an important chapter of traumatology in general. Because of the raising prevalence of child osteoarticular traumas, as well as new less invasive treatment methods, this theme is always to date. The paper analyzes particular cases of bone fractures that appeared due to minor traumas, on bones with a high brittleness, localized especially on the long bones. Although these fractures on a pathological bone can be seen at all levels of the human skeleton, this paper focuses on fractures located in the proximal third part of the femur. A group of children admitted in the Pediatric Orthopedic Department of "M.S. Curie" Hospital-Bucharest with this diagnostic, were analyzed between 2009 and 2013. PMID:26664486

  8. Interfacial fracture toughness between bovine cortical bone and cements.

    PubMed

    Lucksanasombool, P; Higgs, W A J; Higgs, R J E D; Swain, M V

    2003-03-01

    To evaluate the bonding strength of the interfaces within the cemented arthroplasty system, various mechanical tests have been used. Conventional push-out and pull-out tests cannot reveal the actual bonding property of the interface because of the significant influence of surface roughness on the measured adhesion and the failure to account for the mismatch of elastic modulus across the interface. An alternative fracture mechanics approach, which considers the mix of opening and shear modes of the crack tip loading associated with the testing system and the elastic mismatch of materials across the interface, was used to evaluate the bonding ability of various cements. The four-point bend interfacial delamination test by Charalambides et al. (J. Appl. Mech. 56 (1989) 77; Mech. Mater. 8 (1990) 269) was used to quantify the bonding ability of cements. This method is arguably more suitable since the applied loading mode is comparable to the nature of loading within the prosthetic system, which is primarily bending. The bovine bone specimens were polished to mirror finish to eliminate bonding by mechanical interlocking. The results revealed minimal bonding for the conventional bone cement (PMMA) whereas substantial bonding was evident for the glass-ionomer cements tested. However, only the conventional glass-ionomer cements showed evidence of bonding on testing, while the resin-modified glass-ionomer cement (poly-HEMA) did not. The latter appeared to debond before testing because of excessive expansion stresses associated with swelling in water. PMID:12527256

  9. Development of an Ex Vivo Protocol to Model Bone Fracture in Laying Hens Resulting from Collisions

    PubMed Central

    Toscano, Michael J.; Wilkins, Lindsay J.; Millburn, Georgina; Thorpe, Katherine; Tarlton, John F.

    2013-01-01

    Fractures of the keel bone, a bone extending ventrally from the sternum, are a serious health and welfare problem in free range laying hens. Recent findings suggest that a major cause of keel damage within extensive systems is collisions with internal housing structures, though investigative efforts have been hindered by difficulties in examining mechanisms and likely influencing factors at the moment of fracture. The objectives of this study were to develop an ex vivo impact protocol to model bone fracture in hens caused by collision, to assess impact and bird-related factors influencing fracture occurrence and severity, and to identify correlations of mechanical and structural properties between different skeletal sites. We induced keel bone fractures in euthanized hens using a drop-weight impact tester able to generate a range of impact energies, producing fractures that replicate those commonly found in commercial settings. The results demonstrated that impact energies of a similar order to those expected in normal housing were able to produce fractures, and that greater collision energies resulted in an increased likelihood of fractures and of greater severity. Relationships were also seen with keel’s lateral surface bone mineral density, and the peak reactive force (strength) at the base of the manubrial spine. Correlations were also identified between the keel and long bones with respect to both strength and bone mineral density. This is the first study able to relate impact and bone characteristics with keel bone fracture at the moment of collision. Greater understanding of these relationships will provide means to reduce levels of breakage and severity in commercial systems. PMID:23785487

  10. The role of bone marrow-derived cells in bone fracture repair in a green fluorescent protein chimeric mouse model

    SciTech Connect

    Taguchi, Kazuhiro . E-mail: s3061@nms.ac.jp; Ogawa, Rei; Migita, Makoto; Hanawa, Hideki; Ito, Hiromoto; Orimo, Hideo

    2005-05-27

    We investigated the role of bone marrow cells in bone fracture repair using green fluorescent protein (GFP) chimeric model mice. First, the chimeric model mice were created: bone marrow cells from GFP-transgenic C57BL/6 mice were injected into the tail veins of recipient wild-type C57BL/6 mice that had been irradiated with a lethal dose of 10 Gy from a cesium source. Next, bone fracture models were created from these mice: closed transverse fractures of the left femur were produced using a specially designed device. One, three, and five weeks later, fracture lesions were extirpated for histological and immunohistochemical analyses. In the specimens collected 3 and 5 weeks after operation, we confirmed calluses showing intramembranous ossification peripheral to the fracture site. The calluses consisted of GFP- and osteocalcin-positive cells at the same site, although the femur consisted of only osteocalcin-positive cells. We suggest that bone marrow cells migrated outside of the bone marrow and differentiated into osteoblasts to make up the calluses.

  11. Fixation of metatarsal fracture with bone plate in a dromedary heifer.

    PubMed

    Siddiqui, S A; Siddiqui, M I; Telfah, M N; Hashmi, S

    2013-01-01

    An oblique fracture of the distal third of the right metatarsus in a three-year-old dromedary heifer weighing about 300 kilograms was immobilized with a 4.5 mm broad-webbed 12-hole dynamic compression bone plate and two interfragmental compression screws. The animal showed slight lameness after 16 weeks of surgery that disappeared after removal of the plate. The result was quite encouraging and the fracture healed in 16 weeks without major complications. It is concluded that the fracture of this bone can be successfully handled with bone plating at least in young, light weight animals. PMID:26623307

  12. Effects of Bone Matrix Proteins on Fracture and Fragility in Osteoporosis

    PubMed Central

    Sroga, Grażyna E.

    2012-01-01

    Bone mineral density alone cannot reliably predict fracture risk in humans and laboratory animals. Therefore, other factors including the quality of organic bone matrix components and their interactions may be of crucial importance to understanding of fragility fractures. Emerging research evidence shows, that in addition to collagen, certain noncollagenous proteins (NCPs) play a significant role in the structural organization of bone and influence its mechanical properties. However, their contribution to bone strength still remains largely undefined. Collagen and NCPs undergo different post-translational modifications, which alter the quality of the extracellular matrix and the response of bone to mechanical load. The primary focus of this overview is on NCPs that, together with collagen, contribute to structural and mechanical properties of bone. Current information on several mechanisms through which some NCPs influence bone’s resistance to fracture, including the role of nonenzymatic glycation, is also presented. PMID:22535528

  13. Mechanical test and fractal analysis on anisotropic fracture of cortical bone

    NASA Astrophysics Data System (ADS)

    Yin, Dagang; Chen, Bin; Ye, Wei; Gou, Jihua; Fan, Jinghong

    2015-12-01

    The mechanical properties of the cortical bone of fresh bovine femora along three different directions are tested through four-point bending experiments. It is indicated that the fracture energy along the transversal direction of the bone is distinctly larger than those of the longitudinal and radial directions. The fracture surfaces of the three different directions are observed by scanning electron microscope (SEM). It is shown that the roughness of the fracture surface of the transversal direction is obviously larger than those of the fracture surfaces of the longitudinal and radial directions. It is also revealed that the osteons in the bone are perpendicular to the fracture surface of the transversal direction and parallel to the fracture surfaces of the longitudinal and radial directions. Based on these experimental results, the fractal dimensions of the fracture surfaces of different directions are calculated by box-counting method in MATLAB. The calculated results show that the fractal dimension of the fracture surface of the transversal direction is remarkably larger than those of the fracture surfaces of the longitudinal and radial directions. The fracture energies of different directions are also calculated based on their fractal models. It is denoted that the fracture energy of the transversal direction is remarkably larger than those of the longitudinal and radial directions. The calculated results are in good agreement with the tested results.

  14. Reference point indentation is not indicative of whole mouse bone measures of stress intensity fracture toughness

    PubMed Central

    Carriero, Alessandra; Bruse, Jan L.; Oldknow, Karla J.; Millán, José Luis; Farquharson, Colin; Shefelbine, Sandra J.

    2014-01-01

    Bone fragility is a concern for aged and diseased bone. Measuring bone toughness and understanding fracture properties of the bone are critical for predicting fracture risk associated with age and disease and for preclinical testing of therapies. A reference point indentation technique (BioDent) has recently been developed to determine bone's resistance to fracture in a minimally invasive way by measuring the indentation distance increase (IDI) between the first and last indentations over cyclic indentations in the same position. In this study, we investigate the relationship between fracture toughness KC and reference point indentation parameters (i.e. IDI, total indentation distance (TID) and creep indentation distance (CID)) in bones from 38 mice from six types (C57Bl/6, Balb, oim/oim, oim/+, Phospho1−/− and Phospho1 wild type counterpart). These mice bone are models of healthy and diseased bone spanning a range of fracture toughness from very brittle (oim/oim) to ductile (Phospho1−/−). Left femora were dissected, notched and tested in 3-point bending until complete failure. Contralateral femora were dissected and indented in 10 sites of their anterior and posterior shaft surface over 10 indentation cycles. IDI, TID and CID were measured. Results from this study suggest that reference point indentation parameters are not indicative of stress intensity fracture toughness in mouse bone. In particular, the IDI values at the anterior mid-diaphysis across mouse types overlapped, making it difficult to discern differences between mouse types, despite having extreme differences in stress intensity based toughness measures. When more locations of indentation were considered, the normalised IDIs could distinguish between mouse types. Future studies should investigate the relationship of the reference point indentation parameters for mouse bone in other material properties of the bone tissue in order to determine their use for measuring bone quality. PMID:25280470

  15. Biochemical Markers of Bone Turnover in Percutaneous Vertebroplasty for Osteoporotic Compression Fracture

    SciTech Connect

    Komemushi, Atsushi Tanigawa, Noboru; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo; Tokuda, Takanori; Nomura, Motoo; Terada, Jiro; Kamata, Minoru; Sawada, Satoshi

    2008-03-15

    Purpose. To evaluate relationships between biochemical markers of bone turnover, bone mineral density, and new compression fractures following vertebroplasty. Methods. Initially, we enrolled 30 consecutive patients with vertebral compression fractures caused by osteoporosis. Twenty-three of the 30 patients visited our hospital for follow-up examinations for more than 4 weeks after vertebroplasty. The patients were divided into two groups: patients with new fractures (group F) and patients with no new fractures (group N). We analyzed differences in the following parameters between these two groups: serum bone alkaline phosphatase, urinary crosslinked N-telopeptide of type I collagen, urinary deoxypyridinoline, and bone mineral density. Next, the patients were divided into another two groups: patients with higher risk (group H: urinary crosslinked N-telopeptide of type I collagen >54.3 nmol BCE/mmol Cr or urinary deoxypyridinoline >7.6 nmol/mmol Cr, and serum bone alkaline phosphatase <29.0 U/l) and patients with lower risk (group L). We analyzed the difference in the rate of new fractures between these two groups. Results. We identified 9 new fractures in 7 patients. There were no significant differences between groups F and N. We identified 5 new fractures in 3 of the 4 patients in group H, and 4 new fractures in 4 of the 19 patients in group L. There was a significant difference in the rate of new fractures between groups H and L. Conclusions. A combination of high levels of bone resorption markers and normal levels of bone formation markers may be associated with increased risk of new recurrent fractures after percutaneous vertebroplasty.

  16. Effect of Cervus and Cucumis Peptides on Osteoblast Activity and Fracture Healing in Osteoporotic Bone

    PubMed Central

    Wang, Ai-Yuan; Tian, Yue; Yuan, Mei; Zhang, Li; Chen, Ji-Feng; Xu, Wen-Jing; Meng, Hao-Ye; Yu, Xiao-Ming; Wang, Yao-Qin; Guo, Quan-Yi; Lu, Shi-Bi; Peng, Jiang; Wang, Yu

    2014-01-01

    Osteoporosis is associated with delayed and/or reduced fracture healing. As cervus and cucumis are the traditional Chinese treatments for rheumatoid arthritis, we investigated the effect of supplementation of these peptides (CCP) on bone fracture healing in ovariectomized (OVX) osteoporotic rats in vitro and in vivo. CCP enhanced osteoblast proliferation and increased alkaline phosphatase activity, matrix mineralization, and expression of runt-related transcription factor 2 (Runx2), bone morphogenetic protein 4 (BMP4), and osteopontin. In vivo, female Sprague-Dawley rats underwent ovariectomy and the right femora were fractured and fixed by intramedullary nailing 3 months later. Rats received intraperitoneal injections of either CCP (1.67 mg/kg) or physiological saline every day for 30 days. Fracture healing and callus formation were evaluated by radiography, micro-CT, biomechanical testing, and histology. At 12 weeks after fracture, calluses in CCP-treated bones showed significantly higher torsional strength and greater stiffness than control-treated bones. Bones in CCP-treated rats reunified and were thoroughly remodeled, while two saline-treated rats showed no bone union and incomplete remodeling. Taken together, these results indicate that use of CCP after fracture in osteoporotic rats accelerates mineralization and osteogenesis and improves fracture healing. PMID:25525453

  17. 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.

  18. 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.

  19. Reconstruction using 'triangular approximation' of bone grafts for orbital blowout fractures.

    PubMed

    Saiga, Atsuomi; Mitsukawa, Nobuyuki; Yamaji, Yoshihisa

    2015-10-01

    There are many orbital wall reconstruction materials that can be used in surgery for orbital blowout fractures. We consider autogenous bone grafts to have the best overall characteristics among these materials and use thinned, inner cortical tables of the ilium. A bone bender is normally used to shape the inner iliac table to match the orbital shape. Since orbital walls curve three-dimensionally, processing of bone grafts is not easy and often requires much time and effort. We applied a triangular approximation method to the processing of bone grafts. Triangular approximation is a concept used in computer graphics for polygon processing. In this method, the shape of an object is represented as combinations of polygons, mainly triangles. In this study, the inner iliac table was used as a bone graft, and cuts or scores were made to create triangular sections. These triangular sections were designed three-dimensionally so that the shape of the resulting graft approximated to the three-dimensional orbital shape. This method was used in 12 patients with orbital blowout fractures, which included orbital floor fractures, medial wall fractures, and combined inferior and medial wall fractures. In all patients, bone grafts conformed to the orbital shape and good results were obtained. This simple method uses a reasonable and easy-to-understand approach and is useful in the treatment of bone defects in orbital blowout fractures when using a hard graft material. PMID:26297418

  20. Experimental study of damage and fracture of cancellous bone using a digital speckle correlation method.

    PubMed

    Yao, Xuefeng; Wang, Peng; Dai, Ruchun

    2008-01-01

    Cancellous bone is a widespread structure in a creatural body, for instance, in the femoral head and spondyle. The damage evolution and crack growth of cattle cancellous bone were studied under three-point-bending load conditions. A series of speckle images with deformation information surrounding the crack tip were recorded, and the full-field displacement distributions were obtained at different loading levels by means of digital speckle correlation method (DSCM). Characterizations of the damage deformation and fracture of cancellous bone were analyzed. These results provide some useful information for studying the fracture behavior of cancellous bone. PMID:18601571

  1. Evaluation of the Etiologies of Implant Fracture in Patients With Fractures of the Implants of Lower Limbs’ Long Bones

    PubMed Central

    Yeganeh, Ali; Otoukesh, Babak; Kaghazian, Peyman; Yeganeh, Nima; Boddohi, Bahram; Moghtadaei, Mehdi

    2015-01-01

    Background: Orthopedics implants are important tools for treatment of bone fractures. Despite available recommendations for designing and making the implants, there are multiple cases of fracture of these implants in the body. Hence, in this study the frequency of failure of implants in long bones of lower extremities was evaluated. Methods and Materials: In this cross-sectional study, two types of fractured implants in the body were analyzed and underwent metalogical, mechanical, and modeling and stress-bending analysis. Results: The results revealed that the main cause of fractures was decreased mechanical resistance due to inappropriate chemical composition (especially decreased percentages of Nickel and Molybdenum). Conclusions: It may be concluded that following the standard chemical composition and use of optimal making method are the most important works for prevention of failure of implants. PMID:26843735

  2. Gene gun transferring-bone morphogenetic protein 2 (BMP-2) gene enhanced bone fracture healing in rabbits

    PubMed Central

    Li, Wenju; Wei, Haifeng; Xia, Chunmei; Zhu, Xiaomeng; Hou, Guozhu; Xu, Feng; Song, Xinghua; Zhan, Yulin

    2015-01-01

    Purpose: Transferring the bone morphogenetic protein 2 (BMP-2) genes into the tissues or cells can improve the bone healing of the fracture has been widely accepted. We evaluated the efficiency of using gene gun to transfer the BMP-2 gene thereby affected the healing of a fractured bone. Methods: The vector coding for BMP-2 was constructed by a non-replicating encephalo-myocarditis virus (ECMV)-based vector. The segmental bone defect (1.5 cm) model was created by a wire-saw at the middle part of the radius bone of the New Zealand white rabbits. Then either BMP-2 gene or control vector without BMP-2 gene was injected into the tissues around the fracture site. Healing of the defects was monitored radiographically for 9 weeks, bone consolidation was determined by the Lane-Sandhu score pre- and post-operatively, which can evaluated bone formation, bone connect and bone plasticity. Results: The radiographic score and bone consolidation rates were significantly higher in animals injected with BMP-2 gene group as compared with control vector-injected animals (P<0.05). The control group still showed no radiological signs of stable healing. Western-blot and RT-PCR showed BMP-2 expression was significant increase in the tissues around the site of osseous lesions in comparison with the control vector-injected animals (P<0.05). Conclusions: Our results suggested that BMP-2 gene transferred by gene gun could increase the expression of BMP-2 protein and improved the bone callus formation therefore shortened the time of bone defect healing. PMID:26884910

  3. Photoacoustic and SEM analysis of fracture bone callus to different consolidation times

    NASA Astrophysics Data System (ADS)

    Lomelí Mejia, P. A.; Urriolagoitia, G.; Jiménez Pérez, J. L.; Cruz Orea, A.; Lecona Butron, H.; Villegas Castrejón, H.

    2005-06-01

    The Photoacoustic Spectroscopy (PA) and Scanning Electron Microscopy (SEM) were used to perform a study of fractured bone callus to different consolidation times. From these techniques we obtained optical absorption spectra and pictures of male rat fractured bones at different consolidation times. From these spectra it was possible to observe the presence of p-Nitrophenylphosphatase, characteristic phosphatase in rat fractured bones through their absorption peaks which were compared with characteristic reported peaks in the literature for this phosphatase. In this study we showed that p-Nitrophenylphosphatase could be considered as an indicator of the repair process of bone fractures. Through the complementary SEM analysis it was possible to obtain different pictures as the callus grows in the time.

  4. On the multiscale origins of fracture resistance in human bone and its biological degradation

    SciTech Connect

    Zimmermann, Elizabeth A.; Barth, Holly D.; Ritchie, Robert O.

    2012-03-09

    Akin to other mineralized tissues, human cortical bone can resist deformation and fracture due to the nature of its hierarchical structure, which spans the molecular to macroscopic length-scales. Deformation at the smallest scales, mainly through the composite action of the mineral and collagen, contributes to bone?s strength or intrinsic fracture resistance, while crack-tip shielding mechanisms active on the microstructural scale contribute to the extrinsic fracture resistance once cracking begins. The efficiency with which these structural features can resist fracture at both small and large length-scales becomes severely degraded with such factors as aging, irradiation and disease. Indeed aging and irradiation can cause changes to the cross-link profile at fibrillar length-scales as well as changes at the three orders of magnitude larger scale of the osteonal structures, both of which combine to inhibit the bone's overall resistance to the initiation and growth of cracks.

  5. A child with bone fractures and dysmorphic features: remember of pycnodysostosis and craniosynostosis.

    PubMed

    Berenguer, Alberto; Freitas, António Pedro; Ferreira, Gomes; Nunes, José Luis

    2012-01-01

    Accidental bony injuries are common in children. Children may also present with bony injuries following non-accidental injuries. Pathological fractures, though extremely rare, are an important entity and constitute fractures that occur in abnormal bones, usually after minor trauma. Pycnodysostosis is a rare skeletal dysplasia characterised by a clinical phenotype that includes short stature, skull deformities, osteosclerosis, acroosteolysis and bone fragility. Often the disease is diagnosed at an early age as a result of the investigation of short stature. However, the diagnosis is sometimes delayed and must be considered in any child with a history of recurrent or multiple bone fractures and dysmorphic features. The purpose of this report is to describe the clinical, radiological and genetic issues of a 9-year-old girl with a long history of multiple bone fractures. She had been subjected to safeguarding investigations previously and was identified to have dysmorphic features diagnosed as pycnodysostosis associated with craniosynostosis. PMID:23175007

  6. Mechanistic aspects of fracture and R-curve behavior in elk antler bone

    SciTech Connect

    Launey, Maximilien E.; Chen, Po-Yu; McKittrick, Joanna; Ritchie, Robert O.

    2009-11-23

    Bone is an adaptative material that is designed for different functional requirements; indeed, bones have a variety of properties depending on their role in the body. To understand the mechanical response of bone requires the elucidation of its structure-function relationships. Here, we examine the fracture toughness of compact bone of elk antler which is an extremely fast growing primary bone designed for a totally different function than human (secondary) bone. We find that antler in the transverse (breaking) orientation is one of the toughest biological materials known. Its resistance to fracture is achieved during crack growth (extrinsically) by a combination of gross crack deflection/twisting and crack bridging via uncracked 'ligaments' in the crack wake, both mechanisms activated by microcracking primarily at lamellar boundaries. We present an assessment of the toughening mechanisms acting in antler as compared to human cortical bone, and identify an enhanced role of inelastic deformation in antler which further contributes to its (intrinsic) toughness.

  7. Are the High Hip Fracture Rates Among Norwegian Women Explained by Impaired Bone Material Properties?

    PubMed

    Duarte Sosa, Daysi; Vilaplana, Laila; Güerri, Roberto; Nogués, Xavier; Wang-Fagerland, Morten; Diez-Perez, Adolfo; F Eriksen, Erik

    2015-10-01

    Hip fracture rates in Norway rank among the highest in the world, more than double that of Spanish women. Previous studies were unable to demonstrate significant differences between the two populations with respect to bone mass or calcium metabolism. In order to test whether the difference in fracture propensity between both populations could be explained by differences in bone material quality we assessed bone material strength using microindentation in 42 Norwegian and 46 Spanish women with normal BMD values, without clinical or morphometric vertebral fractures, no clinical or laboratory signs of secondary osteoporosis, and without use of drugs with known influence on bone metabolism. Bone material properties were assessed by microindentation of the thick cortex of the mid tibia following local anesthesia of the area using the Osteoprobe device (Active Life Scientific, Santa Barbara, CA, USA). Indentation distance was standardized against a calibration phantom of methylmethacrylate and results, as percentage of this reference value, expressed as bone material strength index units (BMSi). We found that the bone material properties reflected in the BMSi value of Norwegian women was significantly inferior when compared to Spanish women (77 ± 7.1 versus 80.7 ± 7.8, p < 0.001). Total hip BMD was significantly higher in Norwegian women (1.218 g/cm(2) versus 0.938 g/cm(2) , p < 0.001) but regression analysis revealed that indentation values did not vary with BMD r(2)  = 0.03 or age r(2)  = 0.04. In conclusion Norwegian women show impaired bone material properties, higher bone mass, and were taller than Spanish women. The increased height will increase the impact on bone after falls, and impaired bone material properties may further enhance the risk fracture after such falls. These ethnic differences in bone material properties may partly explain the higher propensity for fracture in Norwegian women. PMID:25900016

  8. Measurement of Bone: Diagnosis of SCI-Induced Osteoporosis and Fracture Risk Prediction

    PubMed Central

    Morse, Leslie R.

    2015-01-01

    Background: Spinal cord injury (SCI) is associated with a rapid loss of bone mass, resulting in severe osteoporosis and a 5- to 23-fold increase in fracture risk. Despite the seriousness of fractures in SCI, there are multiple barriers to osteoporosis diagnosis and wide variations in treatment practices for SCI-induced osteoporosis. Methods: We review the biological and structural changes that are known to occur in bone after SCI in the context of promoting future research to prevent or reduce risk of fracture in this population. We also review the most commonly used methods for assessing bone after SCI and discuss the strengths, limitations, and clinical applications of each method. Conclusions: Although dual-energy x-ray absorptiometry assessments of bone mineral density may be used clinically to detect changes in bone after SCI, 3-dimensional methods such as quantitative CT analysis are recommended for research applications and are explained in detail. PMID:26689691

  9. Clinical factors affecting pathological fracture and healing of unicameral bone cysts

    PubMed Central

    2014-01-01

    Background Unicameral bone cyst (UBC) is the most common benign lytic bone lesion seen in children. The aim of this study is to investigate clinical factors affecting pathological fracture and healing of UBC. Methods We retrospectively reviewed 155 UBC patients who consulted Nagoya musculoskeletal oncology group hospitals in Japan. Sixty of the 155 patients had pathological fracture at presentation. Of 141 patients with follow-up periods exceeding 6 months, 77 were followed conservatively and 64 treated by surgery. Results The fracture risk was significantly higher in the humerus than other bones. In multivariate analysis, ballooning of bone, cyst in long bone, male sex, thin cortical thickness and multilocular cyst were significant adverse prognostic factors for pathological fractures at presentation. The healing rates were 30% and 83% with observation and surgery, respectively. Multivariate analysis revealed that fracture at presentation and history of biopsy were good prognostic factors for healing of UBC in patients under observation. Conclusion The present results suggest that mechanical disruption of UBC such as fracture and biopsy promotes healing, and thus watchful waiting is indicated in these patients, whereas patients with poor prognostic factors for fractures should be considered for surgery. PMID:24884661

  10. Multiple Low Energy Long Bone Fractures in the Setting of Rothmund-Thomson Syndrome

    PubMed Central

    Beckmann, Nicholas

    2015-01-01

    Rothmund-Thomson syndrome is a rare autosomal recessive genodermatosis characterized by a poikilodermatous rash starting in infancy as well as various skeletal anomalies, juvenile cataracts, and predisposition to certain cancers. Although Rothmund-Thomson syndrome is associated with diminished bone mineral density in addition to multiple skeletal abnormalities, there are few reports of the association with stress fractures or pathologic fractures in low energy trauma or delayed healing of fractures. Presented is a case of a young adult male with Rothmund-Thomson syndrome presenting with multiple episodes of long bone fractures caused by low energy trauma with one of the fractures exhibiting significantly delayed healing. The patient was also found to have an asymptomatic stress fracture of the lower extremity, another finding of Rothmund-Thomson syndrome rarely reported in the literature. A thorough review of the literature and comprehensive presentation of Rothmund-Thomson syndrome is provided in conjunction with our case. PMID:26617641

  11. Functional Outcomes After Both Bone Forearm Fractures in Adults.

    PubMed

    Thayer, Mary K; Vaidya, Rahul; Langfitt, Maxwell; Carroll, Eben A; Cannada, Lisa K

    2015-01-01

    The purpose of this study was to evaluate midterm outcomes after both bone forearm fractures. A retrospective review of patients treated with open reduction and internal fixation (ORIF) at three level 1 trauma centers was completed. Eligible patients were sent three questionnaires: Disabilities of the Arm, Shoulder and Hand (DASH), Short Form-12 (SF-12), and questions about postinjury experience. Twenty-nine patients with an average age of 45 years returned the materials. The forms were completed an average of 60 months after ORIF. The mean DASH was 22 for all respondents. Twenty-one subjects participated in physical therapy (72%). Eight patients (28%) screened positive for posttraumatic stress disorder (PTSD). The mean SF-12 physical component score was 39 and the SF-12 mental component score was 40, both of which were lower than the non-PTSD group, indicating a lower subjective level of health (p < .05). The data suggest that, years after surgery, patients have decreased functional outcomes. PMID:26688986

  12. Design of a Model of Forearm Bone Fractures for Educational Purposes

    ERIC Educational Resources Information Center

    Jastaniah, Saddig; Hamdan, Abdulrahman; Alhadrami, Abdullah; Almatrafi, Talal; Arif, Ahmed; Almalki, Hassan

    2016-01-01

    This work explores a new approach to demonstrate possible forearm fractures in humans as an educating means for student radiographers. The Design of abnormal bones are not normally available as phantoms; the manufacturer usually produces normal human musculoskeletal models for educational purposes. Hence fractures and abnormalities are usually…

  13. Brief Report: Bone Fractures in Children and Adults with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Neumeyer, Ann M.; O'Rourke, Julia A.; Massa, Alexandra; Lee, Hang; Lawson, Elizabeth A.; McDougle, Christopher J.; Misra, Madhusmita

    2015-01-01

    Peripubertal boys with autism spectrum disorder (ASD) have lower bone mineral density (BMD) than typically developing controls. However, it is not clear whether lower BMD in ASD results in an increased fracture rate. This study examined the rate of fractures in children and adults with and without ASD using a national database of emergency room…

  14. Weibull Analysis of Fracture Test Data on Bovine Cortical Bone: Influence of Orientation

    PubMed Central

    Ekwaro-Osire, Stephen

    2013-01-01

    The fracture toughness, KIC, of a cortical bone has been experimentally determined by several researchers. The variation of KIC values occurs from the variation of specimen orientation, shape, and size during the experiment. The fracture toughness of a cortical bone is governed by the severest flaw and, hence, may be analyzed using Weibull statistics. To the best of the authors' knowledge, however, no studies of this aspect have been published. The motivation of the study is the evaluation of Weibull parameters at the circumferential-longitudinal (CL) and longitudinal-circumferential (LC) directions. We hypothesized that Weibull parameters vary depending on the bone microstructure. In the present work, a two-parameter Weibull statistical model was applied to calculate the plane-strain fracture toughness of bovine femoral cortical bone obtained using specimens extracted from CL and LC directions of the bone. It was found that the Weibull modulus of fracture toughness was larger for CL specimens compared to LC specimens, but the opposite trend was seen for the characteristic fracture toughness. The reason for these trends is the microstructural and extrinsic toughening mechanism differences between CL and LC directions bone. The Weibull parameters found in this study can be applied to develop a damage-mechanics model for bone. PMID:24385985

  15. Weibull analysis of fracture test data on bovine cortical bone: influence of orientation.

    PubMed

    Khandaker, Morshed; Ekwaro-Osire, Stephen

    2013-01-01

    The fracture toughness, K IC, of a cortical bone has been experimentally determined by several researchers. The variation of K IC values occurs from the variation of specimen orientation, shape, and size during the experiment. The fracture toughness of a cortical bone is governed by the severest flaw and, hence, may be analyzed using Weibull statistics. To the best of the authors' knowledge, however, no studies of this aspect have been published. The motivation of the study is the evaluation of Weibull parameters at the circumferential-longitudinal (CL) and longitudinal-circumferential (LC) directions. We hypothesized that Weibull parameters vary depending on the bone microstructure. In the present work, a two-parameter Weibull statistical model was applied to calculate the plane-strain fracture toughness of bovine femoral cortical bone obtained using specimens extracted from CL and LC directions of the bone. It was found that the Weibull modulus of fracture toughness was larger for CL specimens compared to LC specimens, but the opposite trend was seen for the characteristic fracture toughness. The reason for these trends is the microstructural and extrinsic toughening mechanism differences between CL and LC directions bone. The Weibull parameters found in this study can be applied to develop a damage-mechanics model for bone. PMID:24385985

  16. Nose fracture

    MedlinePlus

    Fracture of the nose; Broken nose; Nasal fracture; Nasal bone fracture; Nasal septal fracture ... A fractured nose is the most common fracture of the face. It usually occurs after an injury and often occurs with ...

  17. Changes of mesenchymal stromal cells mobilization and bone turnover in an experimental bone fracture model in ovariectomized mice

    PubMed Central

    Pang, Jian; Guo, Hai-Ling; Ding, Dao-Fang; Wu, Yu-Yun; Zhao, Yong-Fang; Gu, Xin-Feng; Zheng, Yu-Xin

    2015-01-01

    Objective: The aim of this study was to characterize the mesenchymal stromal cells (MSCs) and endothelial progenitor cells (EPCs) mobilization, and bone turnover in osteoporotic fracture healing in ovariectomized mice. Methods: In total, 112 female C57/BL mice were divided into two groups. The first group was sham-operated (SO), and the other group was ovariectomized (OVX). After three weeks, the right femora of the mice were fractured under anesthesia and internally fixed with steel pin. Peripheral blood and bone marrow were was collected for flow cytometry analysis, at 0 hours (h), 12 h, 24 h, 72 h and 168 h after fracture. MSCs and EPCs levels were assessed using cell surface antigens in different combinations (CD44+ CD34-CD45-, and CD34+ KDR+CD45-) by flow cytometry. At 0, 14, 28 and 42 days after fracture, sera were assayed for circulating levels of procollagen type I-N-terminal propeptide (P1NP) and C-terminal telopeptide of type I-collagen (CTX) by ELISA. Femurs were harvested at 2 weeks and 6 weeks after fracture for X-ray radiography, micro-computed tomography (micro-CT) and histology. Results: Our results showed that bone marrow and peripheral blood MSCs numbers of the OVX mice were significantly lower than the SO mice, at 12 h, 24 h and 72 h after fracture. In addition, circulating P1NP and CTX levels of the OVX mice were significantly higher than the SO mice, at 2 and 4 weeks. Conclusion: Results of the present study revealed disorders of bone marrow MSCs mobilization and bone turnover may partially account for the delay of osteoporotic fracture healing. PMID:26617731

  18. Osteoporotic Fracture: 2015 Position Statement of the Korean Society for Bone and Mineral Research.

    PubMed

    Yoo, Je-Hyun; Moon, Seong-Hwan; Ha, Yong-Chan; Lee, Dong Yeon; Gong, Hyun Sik; Park, Si Young; Yang, Kyu Hyun

    2015-11-01

    Osteoporotic fractures are one of the most common causes of disability and a major contributor to medical care costs worldwide. Prior osteoporotic fracture at any site is one of the strongest risk factors for a new fracture, which occurs very soon after the first fracture. Bone mineral density (BMD) scan, a conventional diagnostic tool for osteoporosis, has clear limitations in diagnosing osteoporotic fractures and identifying the risk of subsequent fractures. Therefore, early and accurate diagnosis of osteoporotic fractures using the clinical definition which is applicable practically and independent of BMD, is essential for preventing subsequent fractures and reducing the socioeconomic burden of these fractures. Fractures caused by low-level trauma equivalent to a fall from a standing height or less at major (hip, spine, distal radius, and proximal humerus) or minor (pelvis, sacrum, ribs, distal femur and humerus, and ankle) sites in adults over age 50, should be first regarded as osteoporotic. In addition, if osteoporotic fractures are strongly suspected on history and physical examination even though there are no positive findings on conventional X-rays, more advanced imaging techniques such as computed tomography, bone scan, and magnetic resonance imaging are necessary as soon as possible. PMID:26713308

  19. Influence of bone mineral density and hip geometry on the different types of hip fracture

    PubMed Central

    Li, Yizhong; Lin, Jinkuang; Cai, Siqing; Yan, Lisheng; Pan, Yuancheng; Yao, Xuedong; Zhuang, Huafeng; Wang, Peiwen; Zeng, Yanjun

    2016-01-01

    The aim of this study was to assess the influence of bone mineral density and hip geometry on the fragility fracture of femoral neck and trochanteric region. There were 95 menopausal females of age ≥ 50 years with fragility fracture of hip, including 55 cases of femoral neck fracture and 40 cases of trochanteric fracture. Another 63 non-fractured females with normal bone mineral density (BMD) were chosen as control. BMD, hip axis length, neck-shaft angle and structural parameters including cross surface area, cortical thickness and buckling ratio were detected and compared. Compared with control group, the patients with femoral neck fracture or trochanteric fractures had significantly lower BMD of femoral neck, as well as lower cross surface area and cortical thickness and higher buckling ratio in femoral neck and trochanteric region. There were no significant differences of BMD and structural parameters in the femoral neck fracture group and intertrochanteric fracture group. Hip axis length and neck-shaft angle were not significantly different among three groups. The significant changes of BMD and proximal femur geometry were present in the fragility fracture of femoral neck and trochanteric region. The different types of hip fractures cannot be explained by these changes. PMID:26773177

  20. Clinical and radiographic evaluation of biodegradable bone plates in the treatment of mandibular body fractures

    PubMed Central

    Elhalawany, Sherin Kamal; Tarakji, Bassel; Azzeghaiby, SN; Alzoghaibi, Ibrahim; Baroudi, Kusai; Nassani, Mohammad Zakaria

    2015-01-01

    Background: Many different systems are available for the treatment of fractures ranging from the heavy compression plates for mandibular reconstruction to low profile plates for mid-facial fixation, and are made either from stainless steel, titanium or vitallium. Recently, biodegradable, self-reinforced polylactide plates and screws have been used for the internal fixation of fractures of the mandible with good results. Aim of this study: This study evaluated clinically the biodegradable bone plates for treatment of mandibular body fracture and to evaluate bone healing during the follow-up period using digital radiography. Materials and Methods: Eight patients had been suffered from mandibular body fractures were treated using Inion CPSTM bioresorbable fixation system and the healing process were followed up using digitised panoramic radiography at first week and after 1, 3 and 6 months. Results: Clinical examination of fractured segments revealed stable fixation across the fracture sites while visual and quantitative assessment of radiograph showed healing process was comparable with results previously reported by titanium bone plates. Conclusion: Open reduction and internal fixation of mandibular fractures using bioresorbable fixation system with a brief period of inter-maxillary fixation have evolved to the point where the physical properties are sufficient to withstand the post-operative loads required for fracture repair of mandibular body fractures. The foreign body reaction is a major material-related problem which requires further studies. PMID:25657494

  1. The effect of strain rate on fracture toughness of human cortical bone: a finite element study.

    PubMed

    Ural, Ani; Zioupos, Peter; Buchanan, Drew; Vashishth, Deepak

    2011-10-01

    Evaluating the mechanical response of bone under high loading rates is crucial to understanding fractures in traumatic accidents or falls. In the current study, a computational approach based on cohesive finite element modeling was employed to evaluate the effect of strain rate on fracture toughness of human cortical bone. Two-dimensional compact tension specimen models were simulated to evaluate the change in initiation and propagation fracture toughness with increasing strain rate (range: 0.08-18 s(-1)). In addition, the effect of porosity in combination with strain rate was assessed using three-dimensional models of micro-computed tomography-based compact tension specimens. The simulation results showed that bone's resistance against the propagation of a crack decreased sharply with increase in strain rates up to 1 s(-1) and attained an almost constant value for strain rates larger than 1 s(-1). On the other hand, initiation fracture toughness exhibited a more gradual decrease throughout the strain rates. There was a significant positive correlation between the experimentally measured number of microcracks and the fracture toughness found in the simulations. Furthermore, the simulation results showed that the amount of porosity did not affect the way initiation fracture toughness decreased with increasing strain rates, whereas it exacerbated the same strain rate effect when propagation fracture toughness was considered. These results suggest that strain rates associated with falls lead to a dramatic reduction in bone's resistance against crack propagation. The compromised fracture resistance of bone at loads exceeding normal activities indicates a sharp reduction and/or absence of toughening mechanisms in bone during high strain conditions associated with traumatic fracture. PMID:21783112

  2. A case of adolescent giant parathyroid adenoma presenting multiple osteolytic fractures and postoperative hungry bone syndrome

    PubMed Central

    Ebina, Kosuke; Miyoshi, Yuji; Izumi, Shinji; Hashimoto, Jun; Naka, Norifumi; Tsukamoto, Yasunori; Kashii, Masafumi; Kaito, Takashi; Yoshikawa, Hideki

    2015-01-01

    Key Clinical Message Primary hyperparathyroidism (PHPT) and postoperative hungry bone syndrome are very rare conditions in adolescents, and may be frequently misdiagnosed as a metastatic bone tumor. However, delay in diagnosis may lead to a fatal preoperative hypercalcemia and postoperative hypocalcemia. PHPT is a differential diagnosis of adolescent hypercalcemia and osteolytic fractures. PMID:26509019

  3. Simulation of fracture of the bone implant with the porous structure

    NASA Astrophysics Data System (ADS)

    Korobenkov, M. V.; Kulkov, S. N.

    2016-08-01

    Different approaches to bone defects reconstruction with the use of ceramic materials have been developed recently. Ceramics are identical with bone matrix, provide biomedical compatibility with bone tissue and possess high strength. But with an overall high strength ceramic implants destruct in dynamic mode. The paper presents a study of the effect of the porosity gradient on the destruction of the bone implants under dynamic loading. It is shown that the fracture behavior of the bone implants is changed with increasing levels of the gradient of porosity.

  4. New form of bone dysplasia with multiple fractures associated with monosomy X.

    PubMed

    Azouz, E M; Chen, M F; Khalifé, S; Cartier, L; Eydoux, P

    1996-12-11

    We report on the clinical, radiologic, and pathologic findings in a 20-week-old fetus with monosomy X and severe hydrops associated with fetal dwarfism. The fetus presented with osteoporosis, bent bones, multiple fractures, and distinctive symmetric submetaphyseal transverse bone interruptions or pseudofractures. We excluded by radiologic and histopathologic examination the diagnoses of osteogenesis imperfecta, hypophosphatasia, campomelic dysplasia, achondrogenesis, hypochondrogenesis, and other types of bone dysplasia. To our knowledge, this is a previously undescribed bone dysplasia associated with monosomy X. This bone dysplasia may be inherited as an X-linked recessive disorder. PMID:8958323

  5. Manual strangulation: experimental approach to the genesis of hyoid bone fractures.

    PubMed

    Lebreton-Chakour, Catherine; Godio-Raboutet, Yves; Torrents, Romain; Chaumoitre, Kathia; Boval, Catherine; Bartoli, Christophe; Adalian, Pascal; Piercecchi-Marti, Marie-Dominique; Thollon, Lionel

    2013-05-10

    Discovery of a fracture of the hyoid bone during forensic autopsy is a feature that raises suspicions of constriction of the neck. Studies have shown the influence of gender and build of the individual on the morphology of this bone. Our aims were to confirm these findings and to develop an experimental protocol for simulating manual strangulation in order to determine the force required to fracture the hyoid bone and the influence of anthropometric parameters on this force. A total of 77 intact hyoid bones were obtained, scanned, modeled, measured and embedded in resin. Using a hydraulic press, we applied force to the distal extremity of the greater horn. The relationships between the parameters of sex, weight and height of the subject, anteroposterior length of the hyoid, width between the greater horns, angle, fusion of the greater horns and force applied were analyzed. Our study confirmed sexual dimorphism, shown by greater length in males (>37.8 mm) than in females, and a larger angle in females (a shorter bone with a width>43.7 mm and an angle>31°01). The study confirmed the positive correlation between the length of the hyoid and the weight and height of the subject (p<0.05). Sixty-seven of the 77 hyoid bones fractured during the experiment (87% fracture rate). Of the fractures, 48% occurred at the junction between the body and the greater horns, 49% in the greater horns (mean distance from the distal extremity of the horn 17.33±4.37 mm), and 3% in the median part of the body. No significant association was found between gender and type of fracture, or between fusion or non-fusion of the horn (p>0.05). Fused bones were not more susceptible to fracture than non-fused bones. Fracture occurred at a mean force of 30.55 N (±18.189). Multiple linear regression showed a significant negative correlation between force required for fracture and age, weight and height of the subject, anteroposterior length and angle. The younger the individual, the slighter their

  6. Fractures

    PubMed Central

    Hall, Michael C.

    1963-01-01

    Recent studies on the epidemiology and repair of fractures are reviewed. The type and severity of the fracture bears a relation to the age, sex and occupation of the patient. Bone tissue after fracture shows a process of inflammation and repair common to all members of the connective tissue family, but it repairs with specific tissue. Cartilage forms when the oxygen supply is outgrown. After a fracture, the vascular bed enlarges. The major blood supply to healing tissue is from medullary vessels and destruction of them will cause necrosis of the inner two-thirds of the cortex. Callus rapidly mineralizes, but full mineralization is achieved slowly; increased mineral metabolism lasts several years after fracture. PMID:13952119

  7. Bone: New guidelines for multistep fracture prevention in men.

    PubMed

    Geusens, Piet P M; van den Bergh, Joop P

    2012-10-01

    Study of the efficacy of fracture prevention approaches has been neglected in men, in comparison with women. Guidelines from the Endocrine Society for the management of osteoporosis and fracture risk in men are thus welcome, but further research into fracture prevention in men is required. PMID:22986460

  8. Facial Bone Fracture Patients Visiting Pusan National University Hospital in Busan and Yangsan: Trends and Risks

    PubMed Central

    Kim, Hyo-Geon; Son, Yong-Hyun; Chung, In-Kyo

    2014-01-01

    Purpose: This study examined patients with facial bone fracture visiting Pusan National University Dental Hospital to understand the trends, and to enhance appropriate care and treatment for patients with facial bone fracture. Methods: We investigated 531 patients presenting with facial bone fracture in Yangsan and 802 patients in Busan from January 2010 to December 2013. We divided the patients by year, month, gender, age, site, and cause to compare with historic data and other studies. Results: The gender ratio was 3.58:1 in Yangsan and 4.31:1 in Busan. Patients aged in their 20s had the highest number of facial bone fractures in both Yangsan and Busan. The most frequent fracture site was the mandible, and the most frequent cause was slip down in both Yangsan and Busan. Conclusion: The investigation and comparison of patients with facial bone fracture who visited Pusan National University Hospital located at Yangsan and Busan from 2010 to 2013 found a difference in the total number of patients at each hospital, but the trends were not significantly different. PMID:27489825

  9. Bone-density-specific fracture risk: A population-based study of the relationship between osteoporosis and vertebral fractures

    SciTech Connect

    Melton, L.J.; Wahner, H.W.; Richelson, L.S.; O'Fallon, W.M.; Dunn, W.L.; Riggs, B.L.

    1985-05-01

    The search for a specific level of bone density that clearly distinguishes patients with osteoporosis from those without has been largely unsuccessful. A different, ''gradient of risk'' model was used to assess the effect of various degrees of osteoporosis on the prevalence of vertebral fractures. The authors measured spinal (L/sub 1/-L/sub 4/) bone mineral (BM) with dual photon absorptiometry in an age-stratified random sample of Rochester, Minnesota women greater than or equal to 35 years old to estimate the distribution of spinal BM in the population of adult woman. The authors also assessed BM among women in the sample who had one or more vertebral fractures to estimate both the total number of women with vertebral fractures in the population and the distribution of spinal BM in such women. These population-based estimates were then used to calculate the prevalence rate of vertebral fracture at various levels of spinal BM. Women with spinal BM greater than or equal to 1.40 g/cm/sup 2/ were free of vertebral fractures. Among women with BM between 1.00 and 1.39 g/cm/sup 2/, the prevalence of vertebral fractures was about 7%. The prevalence rate increased as spinal BM decreased further. Among women with spinal BM<0.60 g/cm/sup 2/, all had at least one vertebral fracture (prevalence=100%). These data indicate that osteoporosis is a necessary cause of age-related vertebral fractures and, at certain low levels, is a sufficient cause of such fractures in conjunction with the activities of daily living.

  10. Concurrent bisphosphonate-related bilateral atypical subtrochanteric fractures and osteonecrosis of the jaw on bone scintigraphy.

    PubMed

    Kim, Jo Eun; Yun, Mijin; Lim, Sung-Kil; Rhee, Yumie

    2015-05-01

    An 82-year-old woman presented with bilateral thigh pain. She had pain in her right thigh operated for a low-trauma fracture 2 years earlier and newly developed pain in her left thigh without trauma. A whole-body bone scan revealed increased tracer uptake in her bilateral subtrochanteric femoral shafts and in the right mandible without evidence of metastatic bone disease. She had been taking bisphosphonates for 7 years to treat osteoporosis and was soon diagnosed with atypical subtrochanteric fractures and bisphosphonate-related osteonecrosis of the jaw. The bone scan simultaneously identified 2 serious adverse effects of long-term use of bisphosphonates. PMID:25706787

  11. Fracture of the laryngeal cartilage. An incidental finding on bone scintigraphy.

    PubMed

    Steuart, R D; Morrison, R T

    1992-10-01

    A patient complaining of headaches and bone pain at multiple sites had Tc-99m MDP scintigraphy performed for possible bone trauma after a motor vehicle accident. Bone imaging revealed a small focal increase in tracer uptake in the area of the laryngeal cartilage. There was some reluctance to place a label on this abnormality because the findings were so unusual. The initial diagnosis was a probable fracture of the laryngeal cartilage. Computed tomography of the neck also demonstrated a fracture but correctly localized it to the thyroid cartilage. PMID:1424360

  12. Study on the changes of metal elemental contents in whole blood and bone during fracture healing

    NASA Astrophysics Data System (ADS)

    Yin, Sha; Guodong, Liu; Wenzheng, Lan; Pingsheng, Liu; Peiqun, Zhang; Han, Lin; Xiaoheng, Wen

    1996-04-01

    The radii of 72 rabbits were fractured by operation and the contents of elements P, S, K, Ca, Fe, Ni, Cu and Zn in whole blood of the rabbits during fracture healing were determined by proton induced X-ray emission (PIXE). The contents of Ca and Fe in whole blood were almost kept constant and the contents of other elements varied significantly during fracture healing. The contents of elements K, Ca, Mn, Fe, Cu and Zn in bone for 48 rabbits fractured in radius of limb during healing were also analyzed by PIXE. Various absorbers were tested to improve the PIXE spectra of bone samples and the spectra with much better quality were obtained using some kinds of combined absorbers. The changes of the contents of elements Sr and Fe in bone were shown as a concave shape and convex one respectively, during healing period.

  13. Increased bone density and decreased bone turnover, but no evident alteration of fracture susceptibility in elderly women with diabetes mellitus.

    PubMed

    Gerdhem, P; Isaksson, A; Akesson, K; Obrant, Karl J

    2005-12-01

    Bone density, bone turnover and fracture susceptibility were evaluated in 1,132 randomly recruited women, all 75 years old. Seventy-four of the women had diabetes, while 1,058 women did not. Areal bone mineral density (aBMD) of the hip and lumbar spine was investigated by dual energy X-ray absorptiometry (DXA), and bone mass of the calcaneus was measured by ultrasound. Urinary deoxypyridinoline/creatinine (U-DPD/Crea) and serum C-terminal cross-linked telopeptide of type 1 collagen (S-CTX) were assessed as markers of bone resorption. Serum bone-specific alkaline phosphatase (S-bone ALP) and serum osteocalcin (S-OC) were assessed as markers of bone formation. Also, serum 25(OH) vitamin D and serum parathyroid hormone (S-PTH) were assessed. Fracture susceptibility was evaluated retrospectively and prospectively for up to 6.5 years. In diabetic women, the aBMD of the femoral neck was 11% higher (p<0.001), and BMD of the lumbar spine was 8% higher (p=0.002) than in non-diabetic women. There was no difference in bone mass by ultrasound of the calcaneus. Women with diabetes had higher BMD of the femoral neck (p<0.001) and lumbar spine (p=0.03) also after correction for differences in body weight. In diabetic women, U-DPD/Crea, S-CTX, and S-OC were decreased when compared with non-diabetic women (p=0.001 or less). After correction for covariance of body weight and plasma creatinine, S-CTX (p<0.001) and S-OC (p<0.001) were still lower in the diabetic women. Diabetic patients had hypovitaminosis D (p=0.008), a difference explained by differences in time spent outdoors and body weight. S-PTH did not differ between the groups. Women with diabetes had no more lifetime fractures (52%) than women without diabetic disease (57%), (p=0.31). This study shows that elderly women with diabetes and without severe renal insufficiency have high bone mass and low bone turnover. The high bone mass and low bone turnover is not likely to have a strong influence on fracture susceptibility

  14. Microscopic Pattern of Bone Fractures as an Indicator of Blast Trauma: A Pilot Study.

    PubMed

    Pechníková, Marketa; Mazzarelli, Debora; Poppa, Pasquale; Gibelli, Daniele; Scossa Baggi, Emilio; Cattaneo, Cristina

    2015-09-01

    The assessment of fractures is a key issue in forensic anthropology; however, very few studies deal with the features of fractures due to explosion in comparison with other traumatic injuries. This study focuses on fractures resulting from blast trauma and two types of blunt force trauma (manual compression and running over), applied to corpses of pigs; 163 osteons were examined within forty fractures by the transmission light microscopy. Blast lesions showed a higher percentage of fracture lines through the Haversian canal, whereas in other types of trauma, the fractures went across the inner lamellae. Significant differences between samples hit by blast energy and those runover or manually compressed were observed (p<0.05). The frequency of pattern A is significantly higher in exploded bones than in runover and compressed. Microscopic analysis of the fracture line may provide information about the type of trauma, especially for what concerns blast trauma. PMID:26259072

  15. Comminuted olecranon fracture fixation with pre-contoured plate: Comparison of composite and cadaver bones

    PubMed Central

    Hamilton Jr, David A; Reilly, Danielle; Wipf, Felix; Kamineni, Srinath

    2015-01-01

    AIM: To determine whether use of a precontoured olecranon plate provides adequate fixation to withstand supraphysiologic force in a comminuted olecranon fracture model. METHODS: Five samples of fourth generation composite bones and five samples of fresh frozen human cadaveric left ulnae were utilized for this study. The cadaveric specimens underwent dual-energy X-ray absorptiometry (DEXA) scanning to quantify the bone quality. The composite and cadaveric bones were prepared by creating a comminuted olecranon fracture and fixed with a pre-contoured olecranon plate with locking screws. Construct stiffness and failure load were measured by subjecting specimens to cantilever bending moments until failure. Fracture site motion was measured with differential variable resistance transducer spanning the fracture. Statistical analysis was performed with two-tailed Mann-Whitney-U test with Monte Carlo Exact test. RESULTS: There was a significant difference in fixation stiffness and strength between the composite bones and human cadaver bones. Failure modes differed in cadaveric and composite specimens. The load to failure for the composite bones (n = 5) and human cadaver bones (n = 5) specimens were 10.67 nm (range 9.40-11.91 nm) and 13.05 nm (range 12.59-15.38 nm) respectively. This difference was statistically significant (P ˂ 0.007, 97% power). Median stiffness for composite bones and human cadaver bones specimens were 5.69 nm/mm (range 4.69-6.80 nm/mm) and 7.55 nm/mm (range 6.31-7.72 nm/mm). There was a significant difference for stiffness (P ˂ 0.033, 79% power) between composite bones and cadaveric bones. No correlation was found between the DEXA results and stiffness. All cadaveric specimens withstood the physiologic load anticipated postoperatively. Catastrophic failure occurred in all composite specimens. All failures resulted from composite bone failure at the distal screw site and not hardware failure. There were no catastrophic fracture failures in the cadaveric

  16. [Treatment of pathological fractures of long tubular bones in childhood using elastic stable intramedullary nailing].

    PubMed

    Knorr, P; Schmittenbecher, P P; Dietz, H G

    1996-06-01

    Pathological or spontaneous fractures in childhood are rare and are mostly caused by benign bone diseases; the fractures must be treated on an individual basis, as there are no constant rules. Since the new method of osteosynthesis called "elastic stable intramedullary nailing" (ESIN) or "embrochage centro-medullaire elastique stable" (ECMES) has demonstrated the best results in the treatment of normal fractures in childhood, this method is rapidly being used in the treatment of spontaneous or pathological fractures. We report our experience in the treatment of spontaneous fractures in childhood with "elastic stable intramedullary nailing", in nine patients with ten fractures. The pathological diagnosis was in 5 cases a juvenile bone cyst; in addition, there were cases of histiocytosis X, lymphangiomatosis, hemangiomatosis and osteoporosis (one each). The location was the femur (two cases) and humerus (seven cases). All fractures healed completely without pseudarthrosis; as complications we saw one incidence of osteomyelitis, one of a second fracture after "elastic stable intramedullary nailing" and one coxa vara in a child with histiocytosis X of the proximal femur. In the 5 children with juvenile bone cysts the nails are still in situ; in two cases the nails had to be changed. PMID:8767136

  17. Brief Report: Bone Fractures in Children and Adults with Autism Spectrum Disorders

    PubMed Central

    Neumeyer, Ann M.; O’Rourke, Julia A.; Massa, Alexandra; Lee, Hang; Lawson, Elizabeth A.; McDougle, Christopher J.; Misra, Madhusmita

    2015-01-01

    Peripubertal boys with autism spectrum disorder (ASD) have lower bone mineral density (BMD) than typically developing controls. However, it is not clear whether lower BMD in ASD results in an increased fracture rate. This study examined the rate of fractures in children and adults with and without ASD using a national database of emergency room visits (Nationwide Emergency Department Sample). A higher odds ratio for hip fractures in children and young adults (3–22 years) as well as older adults (23–50 years) with ASD than those without ASD, and a higher odds ratio for forearm and spine fractures in women ages 23–50 with ASD were found. Further studies are necessary to better understand the decreased bone density in ASD and its implications for fracture development. PMID:25193141

  18. Bone marrow fat composition as a novel imaging biomarker in postmenopausal women with prevalent fragility fractures.

    PubMed

    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

  19. Fractures in Relation to Menstrual Status and Bone Parameters in Young Athletes

    PubMed Central

    Ackerman, Kathryn E.; Cano Sokoloff, Natalia; Maffazioli, Giovana De Nardo; Clarke, Hannah; Lee, Hang; Misra, Madhusmita

    2014-01-01

    Introduction To compare fracture prevalence in oligo-amenorrheic athletes (AA), eumenorrheic athletes (EA), and non-athletes (NA) and determine relationships with bone density, structure and strength estimates. Methods 175 females (100 AA, 35 EA, and 40 NA) 14–25 yo were studied. Lifetime fracture history was obtained through participant interviews. Areal BMD was assessed by DXA at the spine, hip and whole body (WB). Bone structure was assessed by HRpQCT at the radius and tibia, and strength by finite element analysis. Results AA, EA, and NA did not differ in age, sexual maturity, or height. AA had lower BMI, and older menarchal age than EA and NA (p≤0.001). BMD Z-scores were lower in AA vs. EA at the total hip, femoral neck, spine, and whole body (p≤0.001). Lifetime fracture risk was higher in AA than EA and NA (47%, 25.7%, 12.5%, p≤0.001), largely driven by stress fractures in AA vs. EA and NA (32% vs. 5.9% vs. 0%). In AA, those who fractured had lower lumbar and WB BMD Z-scores, vBMD of outer trabecular region in radius and tibia, and trabecular thickness of the radius (p≤0.05). In AA, those who had 2 stress fractures had lower lumbar and WB BMD Z-scores, total cross-sectional area, trabecular vBMD, stiffness and failure load at radius; and lower stiffness and failure load at tibia versus those with <2 stress fracture (p≤0.05). Conclusion Weight-bearing athletic activity increases BMD, but may increase stress fracture risk in those with menstrual dysfunction. Bone microarchitecture and strength differences are more pronounced in AA with multiple stress fractures. This is the first study to examine fractures in relation to bone structure in adolescent female athletes. PMID:25397605

  20. THE EFFECT OF STRAIN RATE ON FRACTURE TOUGHNESS OF HUMAN CORTICAL BONE: A FINITE ELEMENT STUDY

    PubMed Central

    Ural, Ani; Zioupos, Peter; Buchanan, Drew; Vashishth, Deepak

    2011-01-01

    Evaluating the mechanical response of bone under high loading rates is crucial to understanding fractures in traumatic accidents or falls. In the current study, a computational approach based on cohesive finite element modeling was employed to evaluate the effect of strain rate on fracture toughness of human cortical bone. Two-dimensional compact tension specimen models were simulated to evaluate the change in initiation and propagation fracture toughness with increasing strain rate (range: 0.08 to 18 s−1). In addition, the effect of porosity in combination with strain rate was assessed using three-dimensional models of microcomputed tomography-based compact tension specimens. The simulation results showed that bone’s resistance against the propagation of fracture decreased sharply with increase in strain rates up to 1 s−1 and attained an almost constant value for strain rates larger than 1 s−1. On the other hand, initiation fracture toughness exhibited a more gradual decrease throughout the strain rates. There was a significant positive correlation between the experimentally measured number of microcracks and the fracture toughness found in the simulations. Furthermore, the simulation results showed that the amount of porosity did not affect the way initiation fracture toughness decreased with increasing strain rates, whereas it exacerbated the same strain rate effect when propagation fracture toughness was considered. These results suggest that strain rates associated with falls lead to a dramatic reduction in bone’s resistance against crack propagation. The compromised fracture resistance of bone at loads exceeding normal activities indicates a sharp reduction and/or absence of toughening mechanisms in bone during high strain conditions associated with traumatic fracture. PMID:21783112

  1. Ultrasonography in the diagnosis of nasal bone fractures: a comparison with conventional radiography and computed tomography.

    PubMed

    Lee, In Sook; Lee, Jung-Hoon; Woo, Chang-Ki; Kim, Hak Jin; Sol, Yu Li; Song, Jong Woon; Cho, Kyu-Sup

    2016-02-01

    The purpose of this study was to evaluate and compare the diagnostic efficacy of ultrasonography (US) with radiography and multi-detector computed tomography (CT) for the detection of nasal bone fractures. Forty-one patients with a nasal bone fracture who underwent prospective US examinations were included. Plain radiographs and CT images were obtained on the day of trauma. For US examinations, radiologist used a linear array transducer (L17-5 MHz) in 24 patients and hockey-stick probe (L15-7 MHz) in 17. The bony component of the nose was divided into three parts (right and left lateral nasal walls, and midline of nasal bone). Fracture detection by three modalities was subjected to analysis. Furthermore, findings made by each modality were compared with intraoperative findings. Nasal bone fractures were located in the right lateral wall (n = 28), midline of nasal bone (n = 31), or left lateral wall (n = 31). For right and left lateral nasal walls, CT had greater sensitivity and specificity than US or radiography, and better agreed with intraoperative findings. However, for midline fractures of nasal bone, US had higher specificity, positive predictive value, and negative predictive value than CT. Although two US evaluations showed good agreements at all three sites, US findings obtained by the hockey-stick probe showed closer agreement with intraoperative findings for both lateral nasal wall and midline of nasal bone. Although CT showed higher sensitivity and specificity than US or radiography, US found to be helpful for evaluating the midline of nasal bone. Furthermore, for US examinations of the nasal bone, a smaller probe and higher frequency may be required. PMID:25749616

  2. Flow intrusion characteristics and fracture properties of titanium-fibre-reinforced bone cement.

    PubMed

    Topoleski, L D; Ducheyne, P; Cuckler, J M

    1998-09-01

    Two clinically relevant considerations for a new bone cement are its fracture properties and flow intrusion characteristics. We present data for a titanium-fibre-reinforced poly(methyl methacrylate) (Ti-PMMA). The fracture properties presented are a concise review of previously published material, while the flow intrusion observations are new. We performed fracture toughness and fatigue fracture experiments. Two types of fatigue specimens were designed and tested. A 'smooth' specimen represented the extreme case of minimum surface flaws. The lifetime of a 'smooth' specimen incorporates fatigue crack initiation (FCI) and fatigue crack propagation (FCP). 'Notched' specimens were created by machining a sharp notch into cylindrical specimens. The sharp notch effectively eliminated FCI from a random surface flaw and thus we made the assumption that the lifetime of the notched specimen was a function of FCP only. Fatigue testing was performed on rotating-bending fatigue machines until failure. Fibre addition resulted in a significant increase in fracture toughness over the control bone cement. Fibre addition and the combination of fibre addition and centrifugation increased the fatigue crack initiation and propagation resistance of the bone cement. For the intrusion studies, eight femurs were obtained from four dogs. The femurs were prepared following a procedure similar to that in human hip replacement surgery. One of the pair of femurs from each dog was filled with non-reinforced bone cement and the other was filled with Ti-PMMA. A stainless-steel rod was inserted into the cement to simulate the insertion of a prosthesis stem. The cemented bones were sectioned and then stained with Alizarin Red S to distinguish the bone from the PMMA or Ti-PMMA. Because of the irregular bone morphology, it was not practical to quantify intrusion depth, but instead to make general observations on the intrusion characteristics. The Ti fibres did not generally flow into the small openings

  3. Predicting Fractures in an International Cohort using Risk Factor Algorithms, Without Bone Mineral Density

    PubMed Central

    Sambrook, Philip N; Flahive, Julie; Hooven, Fred H; Boonen, Steven; Chapurlat, Roland; Lindsay, Robert; Nguyen, Tuan V; Díez-Perez, Adolfo; Pfeilschifter, Johannes; Greenspan, Susan L; Hosmer, David; Netelenbos, J Coen; Adachi, Jonathan D; Watts, Nelson B; Cooper, Cyrus; Roux, Christian; Rossini, Maurizio; Siris, Ethel S; Silverman, Stuart; Saag, Kenneth G; Compston, Juliet E; LaCroix, Andrea; Gehlbach, Stephen

    2016-01-01

    Clinical risk factors are associated with increased probability of fracture in postmenopausal women. We sought to compare prediction models using self-reported clinical risk factors, excluding bone-mineral density (BMD), to predict incident fracture among postmenopausal women. The GLOW study enrolled women aged ≥55 years were seen at 723 primary care practices in 10 countries. The population comprised 19,586 women aged ≥60 years who were not receiving anti-osteoporosis medication and were followed annually for 2 years. Self-administered questionnaires were used to collect data on characteristics, fracture risk factors, previous fractures, and health status. The main outcome measure compares the c index for models using the WHO Fracture Risk (FRAX), the Garvan Fracture Risk Calculator (FRC), and a simple model using age and prior fracture. Over 2 years, 880 women reported incident fractures including 69 hip fractures, 468 “major fractures” (as defined by FRAX) and 583 “osteoporotic fractures” (as defined by FRC). Using baseline clinical risk factors, both FRAX and FRC showed moderate ability to correctly order hip fracture times (c index for hip fracture: 0.78 and 0.76, respectively). C indices for “major” and “osteoporotic” fractures showed lower values, at 0.61 and 0.64. Neither algorithm was better than the model based on age+fracture history alone (c index for hip fracture: 0.78). In conclusion, estimation of fracture risk in an international primary care population of postmenopausal women can be made using clinical risk factors alone, without BMD. However, more sophisticated models incorporating multiple clinical risk factors including falls were not superior to more parsimonious models in predicting future fracture in this population. PMID:21887705

  4. Bone SPECT/CT of Femoral Head Subchondral Insufficiency Fracture.

    PubMed

    Motomura, Goro; Yamamoto, Takuaki; Karasuyama, Kazuyuki; Iwamoto, Yukihide

    2015-09-01

    Subchondral insufficiency fracture of the femoral head may be confused with osteonecrosis, mainly because of radiological overlap. SPECT/CT with Tc-99 m hydroxymethylene diphosphonate images in 7 patients with subchondral insufficiency fracture were retrospectively reviewed and compared with those from 11 patients with symptomatic early osteonecrosis. In all of the hips with subchondral insufficiency fracture, SPECT/CT showed increased uptake at the subchondral lesions of the femoral head. On the other hand, in all of the hips with osteonecrosis, absence of uptake was confirmed at the subchondral lesions. SPECT/CT may assist in differentiating subchondral insufficiency fracture from osteonecrosis. PMID:26164176

  5. Treatment of an open distal tibia fracture with segmental bone loss in combination with a closed proximal tibia fracture: a case report.

    PubMed

    Park, Jin; Yang, Kyu Hyun

    2012-08-01

    The treatment of open distal tibia fractures remains challenging, particularly when the fracture is infected and involves segmental bone loss. We report the case of a 38-year-old man who sustained an open distal tibiofibular fracture with segmental bone loss and a closed proximal tibial fracture. The fractures were initially fixed with a temporary external fixator. The open distal tibial fracture was infected, and the skin was covered after the wound became culture negative. The tibia was then internally transported with a ring external fixator; the closed fracture of the proximal tibia served as the corticotomy for internal transport without conventional corticotomy. After 5 cm internal transport, the docking site of the distal tibia was fixed with a locking plate and autogenous cancellous bone graft. Bone graft was also used to the distal tibiofibular space to achieve distal tibiofibular synostosis. We describe one treatment option for an infected open fracture of the distal tibia with segmental bone loss that is accompanied by a closed fracture of the proximal tibia. This method can treat two fractures simultaneously. PMID:22526200

  6. Carboxylation of osteocalcin may be related to bone quality: a possible mechanism of bone fracture prevention by vitamin K.

    PubMed

    Sugiyama, T; Kawai, S

    2001-01-01

    Vitamin K is essential for the carboxylation of glutamic acid residues, such as osteocalcin. Recent studies have reported that vitamin K reduces vertebral and hip fractures without increasing bone mass in patients with osteoporosis, suggesting that vitamin K could affect bone quality. However, the mechanism is unknown. To investigate the involvement of the carboxylation of osteocalcin in bone quality, the present preliminary study examined serum bone markers and ultrasound velocity, a possible indicator of bone quality, in 14 healthy prepubertal children (eight boys and six girls) aged between 7 and 12 years. Venous blood was collected between 0800 and 0900 h after an overnight fast, and serum levels of intact, carboxylated and undercarboxylated osteocalcin, bone-specific alkaline phosphatase and type I procollagen carboxyl extension peptide were measured. Speed of sound in the right tibia was measured using a SoundScan 2000 Compact (Myriad Ultrasound System, Rehovot, Israel). As a result, there was no significant correlation between the serum bone markers and the Z score for the speed of sound. In contrast, the ratio of serum carboxylated osteocalcin to serum intact osteocalcin was positively correlated with the Z score for the speed of sound (r = 0.621, P = 0.016). These findings suggest, for the first time, that carboxylation of osteocalcin is related to bone quality. Further studies are needed to clarify the role of carboxylation of osteocalcin in bone, and this will provide a new insight into the mechanism of vitamin K treatment in osteoporosis. PMID:11368299

  7. Periosteal PTHrP Regulates Cortical Bone Remodeling During Fracture Healing.

    PubMed

    Wang, Meina; Nasiri, Ali R; Broadus, Arthur E; Tommasini, Steven M

    2015-12-01

    Parathyroid hormone-related protein (PTHrP) is widely expressed in the fibrous outer layer of the periosteum (PO), and the PTH/PTHrP type I receptor (PTHR1) is expressed in the inner PO cambial layer. The cambial layer gives rise to the PO osteoblasts (OBs) and osteoclasts (OCs) that model/remodel the cortical bone surface during development as well as during fracture healing. PTHrP has been implicated in the regulation of PO modeling during development, but nothing is known as regards a role of PTHrP in this location during fracture healing. We propose that PTHrP in the fibrous layer of the PO may be a key regulatory factor in remodeling bone formation during fracture repair. We first assessed whether PTHrP expression in the fibrous PO is associated with PO osteoblast induction in the subjacent cambial PO using a tibial fracture model in PTHrP-lacZ mice. Our results revealed that both PTHrP expression and osteoblast induction in PO were induced 3 days post-fracture. We then investigated a potential functional role of PO PTHrP during fracture repair by performing tibial fracture surgery in 10-week-old CD1 control and PTHrP conditional knockout (PTHrP cKO) mice that lack PO PTHrP. We found that callus size and formation as well as woven bone mineralization in PTHrP cKO mice were impaired compared to that in CD1 mice. Concordant with these findings, functional enzyme staining revealed impaired OB formation and OC activity in the cKO mice. We conclude that deleting PO PTHrP impairs cartilaginous callus formation, maturation and ossification as well as remodeling during fracture healing. These data are the initial genetic evidence suggesting that PO PTHrP may induce osteoblastic activity and regulate fracture healing on the cortical bone surface. PMID:26164475

  8. Fracture mechanics of human cortical bone: The relationship of geometry, microstructure and composition with the fracture of the tibia, femoral shaft and the femoral neck

    NASA Astrophysics Data System (ADS)

    Yeni, Yener Nail

    Bone fracture is a major health problem in old population with its complications leading to mortality and morbidity. Therapies mostly involve preventing bone mass loss. Individuals with high bone mass, however, may still suffer fractures suggesting that additional components such as bone microstructure and composition may be responsible for increased fracture risk in the elderly. The relationship of bone constituents with bone fragility, however, is not well-understood. A better understanding of these relationships will help improving therapies by controlling the relevant biological processes. Bone is a composite material with many constituents such as osteons embedded with vascular channels, collagen fibers, mineral crystals, etc. The nature of interfacing between these constituents makes bone a more complex material. Bone also has a structure that adapts itself, both internally and externally, to better fit its needs. This suggested that, unlike man-made materials, a relationship between material properties and structural properties may exist. Because bone has some similarities with engineering composite materials and also experiences microcracks, a fracture mechanics approach would be more appropriate for investigating its fragility. Choosing mode I and mode II fracture toughness (Gsb{Ic} and Gnsb{IIc}, respectively) as indicators of bone fragility, their relationship with bone microstructure (porosity, osteon morphology, mineral crystal imperfection and microdamage), composition (density, mineral, organic, water and collagen content) and macrostructure (thickness, diameter and moment of inertia of the shaft and angle between the femoral neck and femoral shaft from different views) was investigated. Use of x-ray radiogrammetry for detecting the latter was tested. Differences among the femoral shaft, femoral neck and the tibia were investigated for an age range of 22-94 years. In general, fracture toughness increased with increasing bone quantity. However, the

  9. [Stress fractures of the navicular bone. Roentgen diagnosis of a rare fracture].

    PubMed

    Kirschberger, R; Graff, K H; Henning, A

    1985-03-01

    Stress fracture of the tarsal navicular are rare and their diagnosis is often delayed. 1982 and 1983 we found stress fractures of the os naviculare pedis in 16 patients, 8 fractures were complete and 10 incomplete. Three types of radiographic findings are sclerosis, radiolucency and radiolucency with sclerotic borders. The fractures were localized in the middle third of the tarsal navicular. Laminography is necessary to evaluate the radiographic changes and their extension. PMID:3991908

  10. The relation of microdamage to fracture and material property degradation in human cortical bone tissue

    NASA Astrophysics Data System (ADS)

    Akkus, Ozan

    This dissertation investigates the relation of microdamage to fracture and material property degradation of human cortical bone tissue. Fracture resistance and fatigue crack growth of microcracks were examined experimentally and material property degradation was examined through theoretical modeling. To investigate the contribution of microdamage to static fracture resistance, fracture toughness tests were conducted in the transverse and longitudinal directions to the osteonal orientation of normal bone tissue. Damage accumulation was monitored by acoustic emission during testing and was spatially observed by histological observation following testing. The results suggested that the propagation of the main crack involved weakening of the tissue by diffuse damage at the fracture plane and by formation of linear microcracks away from the fracture plane for the transverse specimens. For the longitudinal specimens, growth of the main crack occurred in the form of separations at lamellar interfaces. Acoustic emission results supported the histological observations. To investigate the contribution of ultrastructure to static fracture resistance, fracture toughness tests were conducted after altering the collagen phase of the bone tissue by gamma radiation. A significant decrease in the fracture toughness, Work-to-Fracture and the amount damage was observed due to irradiation in both crack growth directions. For cortical bone irradiated at 27.5kGy, fracture toughness is reduced due to the inhibition of damage formation at and near the crack tip. Microcrack fatigue crack growth and arrest were investigated through observations of surface cracks during cyclic loading. At the applied cyclic stresses, the microcracks propagated and arrested in less than 10,000 cycles. In addition, the microcracks were observed not to grow beyond a length of 150mum and a DeltaK of 0.5MNm-3/2, supporting a microstructural barrier concept. Finally, the contribution of linear microcracks to

  11. Bone Fractures Following External Beam Radiotherapy and Limb-Preservation Surgery for Lower Extremity Soft Tissue Sarcoma: Relationship to Irradiated Bone Length, Volume, Tumor Location and Dose

    SciTech Connect

    Dickie, Colleen I.; Parent, Amy L.; Griffin, Anthony M.; Fung, Sharon; Chung, Peter W.M.; Catton, Charles N.; Ferguson, Peter C.; Wunder, Jay S.; Bell, Robert S.; Sharpe, Michael B.; O'Sullivan, Brian

    2009-11-15

    Purpose: To examine the relationship between tumor location, bone dose, and irradiated bone length on the development of radiation-induced fractures for lower extremity soft tissue sarcoma (LE-STS) patients treated with limb-sparing surgery and radiotherapy (RT). Methods and Materials: Of 691 LE-STS patients treated from 1989 to 2005, 31 patients developed radiation-induced fractures. Analysis was limited to 21 fracture patients (24 fractures) who were matched based on tumor size and location, age, beam arrangement, and mean total cumulative RT dose to a random sample of 53 nonfracture patients and compared for fracture risk factors. Mean dose to bone, RT field size (FS), maximum dose to a 2-cc volume of bone, and volume of bone irradiated to >=40 Gy (V40) were compared. Fracture site dose was determined by comparing radiographic images and surgical reports to fracture location on the dose distribution. Results: For fracture patients, mean dose to bone was 45 +- 8 Gy (mean dose at fracture site 59 +- 7 Gy), mean FS was 37 +- 8 cm, maximum dose was 64 +- 7 Gy, and V40 was 76 +- 17%, compared with 37 +- 11 Gy, 32 +- 9 cm, 59 +- 8 Gy, and 64 +- 22% for nonfracture patients. Differences in mean, maximum dose, and V40 were statistically significant (p = 0.01, p = 0.02, p = 0.01). Leg fractures were more common above the knee joint. Conclusions: The risk of radiation-induced fracture appears to be reduced if V40 <64%. Fracture incidence was lower when the mean dose to bone was <37 Gy or maximum dose anywhere along the length of bone was <59 Gy. There was a trend toward lower mean FS for nonfracture patients.

  12. An isolated hyoid bone fracture caused by blunt trauma to the neck.

    PubMed

    Erdogan, Baris; Erdogan, Mehmet Ozgur; Colak, Sahin; Kibici, Ozge; Bozan, Korkut; Alper, Baris

    2015-11-01

    Hyoid bone fractures due to blunt trauma are exceedingly rare. Here, we present an isolated hyoid bone fracture caused by blunt trauma as well as a detailed discussion of the injury and treatment options. A 32-year-old male was admitted to emergency department with odynophagia and severe neck pain. He had been hit in the neck with a metal rod during a fight. Computed tomography scan revealed a fracture on hyoid bone and local swelling of adjacent soft tissues. The patient\\'s head was elevated, and ice packs were used to reduce the swelling. Diclofenac sodium and prednisolone were administered. Patient was discharged with a recommendation of out-patient control. Odynophagia, dysphagia and dyspnoea should alert the physician to possible hyoid or laryngeal damage. Fibre optic laryngoscopy and neck CT are important diagnostic steps to reveal a possible life-threatening injury. Conservative treatment is usually adequate, and patients rarely require surgical intervention. PMID:26564301

  13. Audiologic Patterns of Otic Capsule Preserving Temporal Bone Fracture: Effects of the Affected Subsites

    PubMed Central

    Kim, So Young; Kim, Yoon Joong; Kim, Young Ho; Park, Min-Hyun

    2016-01-01

    Objectives. This study was aimed to assess the relationship between the type of temporal bone area involved and conductive hearing loss. Methods. We enrolled 97 patients who visited the otolaryngology clinics of Seoul National University Hospital or Boramae Medical Center, Seoul Metropolitan Government-Seoul National University with temporal bone fracture between January 2004 and January 2014. Audiometric parameters, including initial and improved air-bone (AB) conduction gap values, were reviewed in accordance with the temporal bone computed tomography (external auditory canal [EAC], middle ear [ME], mastoid [M], and ossicle [O]). Results. Patients with ossicular chain involvement exhibited a larger AB gap compared to those with no ossicular chain involvement at 250, 1,000, 2,000, and 4,000 Hz. Among the groups without ossicular chain involvement, the initial AB gap was largest in patients with EAC+ME+M involvement, followed by the ME+M and M-only involvement groups. The greatest improvement in the AB gap was observed in the EAC+ME+M group followed by the ME+M and M-only groups, irrespective of ossicular chain involvement. Improvements in AB gap values were smallest at 2,000 Hz. Conclusion. Conductive hearing loss pattern differed according to the temporal bone area involved. Therefore, areas such as the hematoma and hemotympanum, as well as the fracture line of the temporal bone area, must be evaluated to predict audiologic patterns with otic capsule preserving temporal bone fracture. PMID:27337953

  14. Virtual plate pre-bending for the long bone fracture based on axis pre-alignment.

    PubMed

    Liu, Bin; Luo, Xinjian; Huang, Rui; Wan, Chao; Zhang, Bingbing; Hu, Weihua; Yue, Zongge

    2014-06-01

    In this paper, a modeling and visualizing system for assisting surgeons in correctly registering for the closed fracture reduction surgery is presented. By using this system, the geometric parameters of the target fixation plate before the long bone fracture operation can be obtained. The main processing scheme consists of following steps: firstly (image data process), utilize the Curvelet transform to denoise the CT images of fracture part and then reconstruct the 3D models of the broken bones. Secondly (pre-alignment), extract the axial lines of the broken bones and spatially align them. Then drive the broken bone models to be pre-aligned. Thirdly (mesh segmentation), a method based on vertex normal feature is utilized to obtain the broken bone cross-sections mesh models. Fourthly (fine registration), the ICP (Iterative Closest Point) algorithm is used to register the cross-sections and the broken bone models are driven to achieve the fine registration posture. Lastly (plate fitting), an accurate NURBS surface fitting method is used to construct the virtual plate. The experiment proved that the obtained models of the pre-bended plates were closely bonded to the surface of the registered long bone models. Finally, the lengths, angles and other interested geometric parameters can be measured on the plate models. PMID:24598409

  15. Pure orbital blowout fractures reconstructed with autogenous bone grafts: functional and aesthetic outcomes.

    PubMed

    Kronig, S A J; van der Mooren, R J G; Strabbing, E M; Stam, L H M; Tan, J A S L; de Jongh, E; van der Wal, K G H; Paridaens, D; Koudstaal, M J

    2016-04-01

    The purpose of this study was to investigate the ophthalmic clinical findings following surgical reconstruction with autogenous bone grafts of pure blowout fractures. A retrospective review of 211 patients who underwent surgical repair of an orbital fracture between October 1996 and December 2013 was performed. Following data analysis, 60 patients who were followed up over a period of 1 year were included. A solitary floor fracture was present in 38 patients and a floor and a medial wall fracture in 22 patients. Comparing preoperative findings between these two groups, preoperative diplopia and enophthalmos were almost twice as frequent in the group with additional medial wall fractures: diplopia 8% and 14% and enophthalmos 18% and 55%, respectively. One year following surgery there was no diplopia present in either group. In the solitary floor fracture group, 3% still had enophthalmos. It can be concluded that at 1 year following the repair of pure orbital floor fractures using autogenous bone, good functional and aesthetic results can be obtained. In the group with both floor and medial wall fractures, no enophthalmos was found when both walls were reconstructed. When the medial wall was left unoperated, 29% of patients still suffered from enophthalmos after 1 year. PMID:26711249

  16. Combined Measures of Dynamic Bone Quality and Postural Balance--A Fracture Risk Assessment Approach in Osteoporosis.

    PubMed

    Bhattacharya, Amit; Watts, Nelson B; Dwivedi, Alok; Shukla, Rakesh; Mani, Ashutosh; Diab, Dima

    2016-01-01

    We evaluated functional measures of neuromuscular integrity and bone's resistance to fracture as a combined tool in discriminating osteoporosis patients with and without fractures. Functional aspects of neuromuscular integrity were quantified with a noninvasive measure of static and dynamic functional postural stability (FPS), and fracture resistance was obtained with bone shock absorption in patients with osteoporosis aged 65-85 and compared our measures with dual-energy X-ray absorptiometry and Fracture Risk Assessment Tool (FRAX [World Health Organization Collaborating Center for Metabolic Bone Diseases, Sheffield, UK]) in women with osteoporosis, some with and some without vertebral fractures. Patients with vertebral fracture showed larger static FPS (postural sway excursion) in the mediolateral and anterior-posterior directions, suggesting poorer balance. Most of the variables of dynamic FPS showed significant differences between fracture and no-fracture groups (e.g., the fracture group took significantly longer during turning, implying poorer dynamic balance control). Also, compared with healthy control subjects, all 4 dynamic FPS responses for osteoporosis patients with and without fracture were significantly poorer, suggesting potential risk for falls. In summary, patients with osteoporosis who have vertebral fractures (compared with patients with similarly low bone mineral density and other nonfracture risk fractures) have not only lower bone shock absorption damping (ζ) but also increased postural imbalance. PMID:25936482

  17. Fracture properties of growth plate cartilage compared to cortical and trabecular bone in ovine femora.

    PubMed

    Tschegg, E K; Celarek, A; Fischerauer, S F; Stanzl-Tschegg, S; Weinberg, A M

    2012-10-01

    Fracture mechanical parameters (notch tensile strength, specific fracture energy/crack resistance and specific crack initiation energy) of epiphyseal plate cartilage, trabecular bone (metaphysis) and cortical bone (diaphysis) were determined on ovine femur specimens. The fracture behaviour before and after crack initiation was recorded in force-displacement diagrams from wedge splitting tests. Crack propagation was stable both during and after the formation of a principal crack. This is the main advantage of the wedge-splitting method by Tschegg in comparison with tensile tests. Microscopy of the epiphyseal plate during fracture showed fibre elongation and tearing in the crack tip region. The results of this study can help to understand the mechanics of epiphyseal plate injuries and the obtained values can be used for computational simulations and models. PMID:23022566

  18. Loss of Gi G-Protein-Coupled Receptor Signaling in Osteoblasts Accelerates Bone Fracture Healing.

    PubMed

    Wang, Liping; Hsiao, Edward C; Lieu, Shirley; Scott, Mark; O'Carroll, Dylan; Urrutia, Ashley; Conklin, Bruce R; Colnot, Celine; Nissenson, Robert A

    2015-10-01

    G-protein-coupled receptors (GPCRs) are key regulators of skeletal homeostasis and are likely important in fracture healing. Because GPCRs can activate multiple signaling pathways simultaneously, we used targeted disruption of G(i) -GPCR or activation of G(s) -GPCR pathways to test how each pathway functions in the skeleton. We previously demonstrated that blockade of G(i) signaling by pertussis toxin (PTX) transgene expression in maturing osteoblastic cells enhanced cortical and trabecular bone formation and prevented age-related bone loss in female mice. In addition, activation of G(s) signaling by expressing the G(s) -coupled engineered receptor Rs1 in maturing osteoblastic cells induced massive trabecular bone formation but cortical bone loss. Here, we test our hypothesis that the G(i) and G(s) pathways also have distinct functions in fracture repair. We applied closed, nonstabilized tibial fractures to mice in which endogenous G(i) signaling was inhibited by PTX, or to mice with activated G(s) signaling mediated by Rs1. Blockade of endogenous G(i) resulted in a smaller callus but increased bone formation in both young and old mice. PTX treatment decreased expression of Dkk1 and increased Lef1 mRNAs during fracture healing, suggesting a role for endogenous G(i) signaling in maintaining Dkk1 expression and suppressing Wnt signaling. In contrast, adult mice with activated Gs signaling showed a slight increase in the initial callus size with increased callus bone formation. These results show that G(i) blockade and G(s) activation of the same osteoblastic lineage cell can induce different biological responses during fracture healing. Our findings also show that manipulating the GPCR/cAMP signaling pathway by selective timing of G(s) and G(i) -GPCR activation may be important for optimizing fracture repair. PMID:25917236

  19. Osteopenia and bone fractures in a man with anorexia nervosa and hypogonadism

    SciTech Connect

    Rigotti, N.A.; Neer, R.M.; Jameson, L.

    1986-07-18

    Women with anorexia nervosa have reduced skeletal mass. Both anorexia and osteopenia are less common in men. We describe a 22-year-old man with anorexia nervosa and severe osteopenia involving both cortical and trabecular bone who developed a pelvic fracture and multiple vertebral compression fractures. He was found to have secondary hypogonadotropic hypogonadism that was reversible with weight gain. This case illustrates the need to consider osteopenia as a potential complication of anorexia nervosa in males as well as females.

  20. Temporal bone fracture following blunt trauma caused by a flying fish.

    PubMed

    Goldenberg, D; Karam, M; Danino, J; Flax-Goldenberg, R; Joachims, H Z

    1998-10-01

    Blunt trauma to the temporal region can cause fracture of the skull base, loss of hearing, vestibular symptoms and otorrhoea. The most common causes of blunt trauma to the ear and surrounding area are motor vehicle accidents, violent encounters, and sports-related accidents. We present an obscure case of a man who was struck in the ear by a flying fish while wading in the sea with resulting temporal bone fracture, sudden deafness, vertigo, cerebrospinal fluid otorrhoea, and pneumocephalus. PMID:10211221

  1. miRNA-29b improves bone healing in mouse fracture model.

    PubMed

    Lee, Wayne Y; Li, Nan; Lin, Sien; Wang, Bin; Lan, Hui Y; Li, Gang

    2016-07-15

    A number of miRNAs regulates bone remodeling and their levels in circulation were associated with bone fracture, however no miRNAs have yet been shown to improve fracture healing directly. This study aimed to investigate the effect of miR-29b-3p on mice femoral fracture healing through site-specific delivery with microbubble-ultrasound system. miR-29b-3p promoted osteogenesis of mouse bone marrow-derived mesenchymal stem cells as indicated with quantitative real-time polymerase chain reaction (qPCR) and Alizarin red S staining. Animal study showed that single injection of miR-29b-3p at week 2 post fracture improved healing outcome as indicated by significant decrease of callus width and area with radiographic analysis without causing significant weight loss. Static bone histomorphometry analysis showed that miR-29b-3p increased bone volume fraction (BV/TV), and micro-computed tomography (micro-CT) measurement showed increased BV/TV of high density bone and bone mineral density (BMD) of the callus. 3 point bending mechanical test showed improved relative stiffness. However, repeated injection of miR-29b-3p at weeks 2 and 3 did not result in additive therapeutic outcome, and caused increased total tissue volume and reduced BMD of the callus. This is the first report showing significant therapeutic effect of miR-29b-3p on femoral fracture healing through site-specific delivery with microbubble-ultrasound system. Further studies are warranted to investigate the underlying mechanisms and to refine the treatment protocol. PMID:27113026

  2. Pathological fractures of the proximal femur due to solitary bone cyst: classification, methods of treatment

    PubMed Central

    Miu, A

    2015-01-01

    Fractures are a very important issue in a child’s orthopedic pathology. Neglected a good amount of time, being considered “not too serious”, or “rare”, having better and faster healing methods and not leaving sequels, like in the case of adults, a child’s fractures remain an important chapter of traumatology in general. Because of the raising prevalence of child osteoarticular traumas, as well as new less invasive treatment methods, this theme is always to date. The paper analyzes particular cases of bone fractures that appeared due to minor traumas, on bones with a high brittleness, localized especially on the long bones. Although these fractures on a pathological bone can be seen at all levels of the human skeleton, this paper focuses on fractures located in the proximal third part of the femur. A group of children admitted in the Pediatric Orthopedic Department of “M.S. Curie” Hospital-Bucharest with this diagnostic, were analyzed between 2009 and 2013. PMID:26664486

  3. Comminuted fracture of the accessory carpal bone removed via an arthroscopic-assisted arthrotomy

    PubMed Central

    Bonilla, Alvaro G.; Santschi, Elizabeth M.

    2015-01-01

    A 16-year-old American paint horse gelding was presented for evaluation of a left forelimb lameness grade III/V. Radiographs and computed tomography revealed a comminuted fracture of the accessory carpal bone involving the entire articulation with the distal radius and the proximal aspect of the articulation with the ulnar carpal bone. Multiple fragments were present in the palmar pouch of the antebrachiocarpal joint. An arthroscopic-assisted open approach was necessary to remove all fractured fragments. Subsequently the horse was re-admitted for lameness and was treated successfully with antibiotics and long-term supportive bandaging. PMID:25694665

  4. Comminuted fracture of the accessory carpal bone removed via an arthroscopic-assisted arthrotomy.

    PubMed

    Bonilla, Alvaro G; Santschi, Elizabeth M

    2015-02-01

    A 16-year-old American paint horse gelding was presented for evaluation of a left forelimb lameness grade III/V. Radiographs and computed tomography revealed a comminuted fracture of the accessory carpal bone involving the entire articulation with the distal radius and the proximal aspect of the articulation with the ulnar carpal bone. Multiple fragments were present in the palmar pouch of the antebrachiocarpal joint. An arthroscopic-assisted open approach was necessary to remove all fractured fragments. Subsequently the horse was re-admitted for lameness and was treated successfully with antibiotics and long-term supportive bandaging. PMID:25694665

  5. Hyponatremia Is Associated With Increased Osteoporosis and Bone Fractures in a Large US Health System Population

    PubMed Central

    Usala, Rachel L.; Fernandez, Stephen J.; Mete, Mihriye; Cowen, Laura; Shara, Nawar M.; Barsony, Julianna

    2015-01-01

    Context: 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. Objective: 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. Design, Setting, and Participants: 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. Main Outcome Measures: Incidence of diagnosis of osteoporosis and fragility fractures of the upper or lower extremity, pelvis, and vertebrae were the outcome measures. Results: 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+. Conclusions: 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. PMID:26083821

  6. A case of multiple bone fractures due to the use of topical corticosteroid therapy for psoriasis.

    PubMed

    Gönül, Müzeyyen; Gönül, Engin

    2015-06-01

    A 45-year-old man who had psoriasis had applied topical clobetasol 17 propionate ointment on his whole body 2-3 times a week after the bath for 20 years. Physical examination showed abdominal distension, atrophy all over the skin, psoriatic plaques on the trunk, and extremities and multiple striae on the shoulders and legs. Morning plasma cortisol level and ACTH stimulation test confirmed the diagnosis of hypothalamic insufficiency. Bone mineral densitometry showed severe osteoporosis. Multiple bone fractures in the vertebrae and costa were detected on lumbar magnetic resonance imaging, the (99)Tc MDP whole-body bone scan, and thoracoabdominal computerized tomography imaging. Topical corticosteroid therapies have possible local and/or systemic side effects such as atrophy, telangiectasia, hypertricosis, and suppression of pituitary-adrenal axis. We present an interesting case with multiple bone fractures caused by long-time topical corticosteroid use. PMID:24913132

  7. In situ observation of fracture behavior of canine cortical bone under bending.

    PubMed

    Lin, Zilan X; Xu, Zhi-Hui; An, Yuehuei H; Li, Xiaodong

    2016-05-01

    Cortical bone provides many important body functions and maintains the rigidness and elasticity of bone. A common failure mode for bone structure is fracture under a bending force. In the current study, the fracture behavior of canine cortical bone under three-point bending was observed in situ using an atomic force microscope (AFM), a scanning electron microscope (SEM), and an optical microscope to examine the fracture process in detail. Nanoindentation was carried out to determine the elastic modulus and hardness of different building blocks of the canine cortical bone. The results have shown that the special structure of Haversian systems has significant effects on directing crack propagation. Although Haversian systems contain previously believed weak points, and micro-cracks initiate within Haversian systems, our findings have demonstrated that macro-cracks typically form around the boundaries of Haversian systems, i.e. the cement lines. Micro-cracks that developed inside Haversian systems have the functions of absorbing and dissipating energy and slow down on expanding when interstitial tissue cannot hold any more pressure, then plastic deformation and fracture occur. PMID:26952434

  8. Effects of fatigue induced damage on the longitudinal fracture resistance of cortical bone.

    PubMed

    Fletcher, Lloyd; Codrington, John; Parkinson, Ian

    2014-07-01

    As a composite material, cortical bone accumulates fatigue microdamage through the repetitive loading of everyday activity (e.g. walking). The accumulation of fatigue microdamage is thought to contribute to the occurrence of fragility fractures in older people. Therefore it is beneficial to understand the relationship between microcrack accumulation and the fracture resistance of cortical bone. Twenty longitudinally orientated compact tension fracture specimens were machined from a single bovine femur, ten specimens were assigned to both the control and fatigue damaged groups. The damaged group underwent a fatigue loading protocol to induce microdamage which was assessed via fluorescent microscopy. Following fatigue loading, non-linear fracture resistance tests were undertaken on both the control and damaged groups using the J-integral method. The interaction of the crack path with the fatigue induced damage and inherent toughening mechanisms were then observed using fluorescent microscopy. The results of this study show that fatigue induced damage reduces the initiation toughness of cortical bone and the growth toughness within the damage zone by three distinct mechanisms of fatigue-fracture interaction. Further analysis of the J-integral fracture resistance showed both the elastic and plastic component were reduced in the damaged group. For the elastic component this was attributed to a decreased number of ligament bridges in the crack wake while for the plastic component this was attributed to the presence of pre-existing fatigue microcracks preventing energy absorption by the formation of new microcracks. PMID:24715332

  9. Bone Fragility Beyond Strength and Mineral Density: Raman Spectroscopy Predicts Femoral Fracture Toughness in a Murine Model of Rheumatoid Arthritis

    PubMed Central

    Inzana, Jason A.; Maher, Jason R.; Takahata, Masahiko; Schwarz, Edward M.; Berger, Andrew J.; Awad, Hani A.

    2012-01-01

    Clinical prediction of bone fracture risk primarily relies on measures of bone mineral density (BMD). BMD is strongly correlated with bone strength, but strength is independent of fracture toughness, which refers to the bone’s resistance to crack initiation and propagation. In that sense, fracture toughness is more relevant to assessing fragility-related fracture risk, independent of trauma. We hypothesized that bone biochemistry, determined by Raman spectroscopy, predicts bone fracture toughness better than BMD. This hypothesis was tested in tumor necrosis factor-transgenic mice (TNF-tg), which develop inflammatory-erosive arthritis and osteoporosis. The left femurs of TNF-tg and wild type (WT) littermates were measured with Raman spectroscopy and micro-computed tomography. Fracture toughness was assessed by cutting a sharp notch into the anterior surface of the femoral mid-diaphysis and propagating the crack under 3 point bending. Femoral fracture toughness of TNF-tg mice was significantly reduced compared to WT controls (p=0.04). A Raman spectrum-based prediction model of fracture toughness was generated by partial least squares regression (PLSR). Raman spectrum PLSR analysis produced strong predictions of fracture toughness, while BMD was not significantly correlated and produced very weak predictions. Raman spectral components associated with mineralization quality and bone collagen were strongly leveraged in predicting fracture toughness, reiterating the limitations of mineralization density alone. PMID:23261243

  10. Bone morphogenetic protein 2 and decorin expression in old fracture fragments and surrounding tissues.

    PubMed

    Han, X G; Wang, D K; Gao, F; Liu, R H; Bi, Z G

    2015-01-01

    Bone morphogenetic protein 2 (BMP-2) can promote fracture healing. Although the complex role BMP-2 in bone formation is increasingly understood, the role of endogenous BMP-2 in nonunion remains unclear. Decorin (DCN) can promote the formation of bone matrix and calcium deposition to control bone morphogenesis. In this study, tissue composition and expression of BMP-2 and DCN were detected in different parts of old fracture zones to explore inherent anti-fibrotic ability and osteogenesis. Twenty-three patients were selected, including eight cases of delayed union and 15 cases of nonunion. Average duration of delayed union or nonunion was 15 months. Fracture fragments and surrounding tissues, including bone grafts, marrow cavity contents, and sticking scars, were categorically sampled during surgery. Through observation and histological testing, component comparisons were made between fracture fragments and surrounding tissue. The expression levels of DCN and BMP-2 in different tissues were detected by immunohistochemical staining and real-time polymerase chain reaction. The expression of DCN and BMP- 2 in different parts of the nonunion area showed that, compared with bone graft and marrow cavity contents, sticking scars had the highest expression of BMP-2. Compared with the marrow cavity contents and sticking scars, bone grafts had the highest expression of DCN. The low antifibrotic and osteogenic activity of the nonunion area was associated with non-co-expression of BMP-2 and DCN. Therefore, the co-injection of osteogenic factor BMP and DCN into the nonunion area can improve the induction of bone formation and enhance the conversion of the old scar, thereby achieving better nonunion treatment. PMID:26400336

  11. Bone Density Changes After Radiation for Extremity Sarcomas: Exploring the Etiology of Pathologic Fractures

    SciTech Connect

    Dhakal, Sughosh; Chen, Jeffrey; McCance, Sean; Rosier, Randy; O'Keefe, Regis; Constine, Louis S.

    2011-07-15

    Purpose: The incidental irradiation (RT) of adjacent bone that takes place during treatment of soft tissue extremity sarcomas is generally presumed to 'weaken' the bone by decreasing its density, which subsequently increases the risk for pathologic fracture. This investigation intended to assess the relative effects on bone density of both RT and diminished mechanical loading secondary to tumor-induced and therapy-induced functional extremity impairment. Methods and Materials: 19 patients treated with surgical excision and RT for soft tissue extremity sarcomas had bone density measured using dual energy X-ray absorptiometry at four sites: the irradiated (A) and contralateral (B) bone, and an uninvolved bone (C) in the treated extremity and its contralateral counterpart (D). Analysis included (1) [A-B], (2) [C-D], (3) [(A-B), - (C-D)], and (4) [(A-B)/B - (C-D)/D]. Results: The mean bone density for all irradiated sites was increased 0.08 {+-} 0.22 g/cm{sup 2} (variance) compared to the contralateral unirradiated side when corrected for weight-bearing effects (3). An average increase in bone density of 9 {+-} 22% (p = 0.08) was also seen when the differences were divided by individual control densities to normalize variation in density of different anatomic sites (4). Conclusions: RT does not routinely decrease bone density when corrected for weight bearing or mechanical effects. The pathogenesis for the known increased risk of pathologic fracture in irradiated bones is likely multifactorial, including possible alterations in bone remodeling that can result in stable, or even increased, bone density. Further clinical and basic studies are needed to confirm our unexpected findings.

  12. Research Perspectives: The 2013 AAOS/ORS Research Symposium on Bone Quality and Fracture Prevention

    PubMed Central

    Donnelly, Eve; Lane, Joseph M.; Boskey, Adele L.

    2016-01-01

    Bone fracture resistance is determined by the amount of bone present (“bone quantity”) and by a number of other geometric and material factors grouped under the term “bone quality.” In May 2013, a workshop was convened among a group of clinicians and basic science investigators to review the current state of the art in Bone Quality and Fracture Prevention and to make recommendations for future directions for research. The AAOS/ORS/OREF workshop was attended by 64 participants, including two representatives of the National Institutes of Arthritis and Musculoskeletal and Skin Diseases and 13 new investigators whose posters stimulated additional interest. A key outcome of the workshop was a set of recommendations regarding clinically relevant aspects of both bone quality and quantity that clinicians can use to inform decisions about patient care and management. The common theme of these recommendations was the need for more education of clinicians in areas of bone quality and for basic science studies to address specific topics of pathophysiology, diagnosis, prevention, and treatment of altered bone quality. In this report, the organizers with the assistance of the speakers and other attendees highlight the major findings of the meeting that justify the recommendations and needs for this field. PMID:24700449

  13. Mason type II radial head fractures fixed with Herbert bone screws.

    PubMed Central

    Pearce, M S; Gallannaugh, S C

    1996-01-01

    The management of radial head fractures remains controversial. Accurate classification of the fracture (Mason) may necessitate the use of special X-ray views (45 degrees arterior oblique or radio-capitellar). We present the results of 19 cases of Mason type II fractures treated operatively by open reduction and internal fixation with the Herbert bone screw. All patients achieved 'good-to-excellent' outcome at follow-up. Our results compare favourably with other forms of treatment for this injury. Images Figure 2 (a) Figure 2 (b) Figure 2 (c) Figure 2 (d) Figure 3 (a) Figure 3 (b) PMID:8758194

  14. Role of mesenchymal stem cells in bone regeneration and fracture repair: a review.

    PubMed

    Wang, Xin; Wang, Yu; Gou, Wenlong; Lu, Qiang; Peng, Jiang; Lu, Shibi

    2013-12-01

    Mesenchymal stem cells (MSCs) are non-haematopoietic stromal stem cells that have many sources, such as bone marrow, periosteum, vessel walls, adipose, muscle, tendon, peripheral circulation, umbilical cord blood, skin and dental tissues. They are capable of self-replication and of differentiating into, and contributing to the regeneration of, mesenchymal tissues, such as bone, cartilage, ligament, tendon, muscle and adipose tissue. The homing of MSCs may play an important role in the repair of bone fractures. As a composite material, the formation and growth of bone tissue is a complex process, including molecular, cell and biochemical metabolic changes. The recruitment of factors with an adequate number of MSCs and the micro-environment around the fracture are effective for fracture repair. Several studies have investigated the functional expression of various chemokine receptors, trophic factors and adhesion molecules in human MSCs. Many external factors affect MSC homing. MSCs have been used as seed cells in building tissue-engineered bone grafts. Scaffolds seeded with MSCs are most often used in tissue engineering and include biotic and abiotic materials. This knowledge provides a platform for the development of novel therapies for bone regeneration with endogenous MSCs. PMID:23948983

  15. TRPV4 deficiency causes sexual dimorphism in bone metabolism and osteoporotic fracture risk.

    PubMed

    van der Eerden, B C J; Oei, L; Roschger, P; Fratzl-Zelman, N; Hoenderop, J G J; van Schoor, N M; Pettersson-Kymmer, U; Schreuders-Koedam, M; Uitterlinden, A G; Hofman, A; Suzuki, M; Klaushofer, K; Ohlsson, C; Lips, P J A; Rivadeneira, F; Bindels, R J M; van Leeuwen, J P T M

    2013-12-01

    We explored the role of transient receptor potential vanilloid 4 (TRPV4) in murine bone metabolism and association of TRPV4 gene variants with fractures in humans. Urinary and histomorphometrical analyses demonstrated reduced osteoclast activity and numbers in male Trpv4(-/-) mice, which was confirmed in bone marrow-derived osteoclast cultures. Osteoblasts and bone formation as shown by serum procollagen type 1 amino-terminal propeptide and histomorphometry, including osteoid surface, osteoblast and osteocyte numbers were not affected in vivo. Nevertheless, osteoblast differentiation was enhanced in Trpv4(-/-) bone marrow cultures. Cortical and trabecular bone mass was 20% increased in male Trpv4(-/-) mice, compared to sex-matched wild type (Trpv4(+/+)) mice. However, at the same time intracortical porosity was increased and bone matrix mineralization was reduced. Together, these lead to a maximum load, stiffness and work to failure of the femoral bone, which were not different compared to Trpv4(+/+) mice, while the bone material was less resistant to stress and less elastic. The differential impacts on these determinants of bone strength were likely responsible for the lack of any changes in whole bone strength in the Trpv4(-/-) mice. None of these skeletal parameters were affected in female Trpv4(-/-) mice. The T-allele of rs1861809 SNP in the TRPV4 locus was associated with a 30% increased risk (95% CI: 1.1-1.6; p=0.013) for non-vertebral fracture risk in men, but not in women, in the Rotterdam Study. Meta-analyses with the population-based LASA study confirmed the association with non-vertebral fractures in men. This was lost when the non-population-based studies Mr. OS and UFO were included. In conclusion, TRPV4 is a male-specific regulator of bone metabolism, a determinant of bone strength, and a potential risk predictor for fractures through regulation of bone matrix mineralization and intra-cortical porosity. This identifies TRPV4 as a unique sexually

  16. The Extravehicular Suit Impact Load Attenuation Study for Use in Astronaut Bone Fracture Prediction

    NASA Technical Reports Server (NTRS)

    Lewandowski, Beth E.; Gilkey, Kelly M.; Sulkowski, Christina M.; Samorezov, Sergey; Myers, Jerry G.

    2011-01-01

    The NASA Integrated Medical Model (IMM) assesses the risk, including likelihood and impact of occurrence, of all credible in-flight medical conditions. Fracture of the proximal femur is a traumatic injury that would likely result in loss of mission if it were to happen during spaceflight. The low gravity exposure causes decreases in bone mineral density which heightens the concern. Researchers at the NASA Glenn Research Center have quantified bone fracture probability during spaceflight with a probabilistic model. It was assumed that a pressurized extravehicular activity (EVA) suit would attenuate load during a fall, but no supporting data was available. The suit impact load attenuation study was performed to collect analogous data. METHODS: A pressurized EVA suit analog test bed was used to study how the offset, defined as the gap between the suit and the astronaut s body, impact load magnitude and suit operating pressure affects the attenuation of impact load. The attenuation data was incorporated into the probabilistic model of bone fracture as a function of these factors, replacing a load attenuation value based on commercial hip protectors. RESULTS: Load attenuation was more dependent on offset than on pressurization or load magnitude, especially at small offsets. Load attenuation factors for offsets between 0.1 - 1.5 cm were 0.69 +/- 0.15, 0.49 +/- 0.22 and 0.35 +/- 0.18 for mean impact forces of 4827, 6400 and 8467 N, respectively. Load attenuation factors for offsets of 2.8 - 5.3 cm were 0.93 +/- 0.2, 0.94 +/- 0.1 and 0.84 +/- 0.5, for the same mean impact forces. Reductions were observed in the 95th percentile confidence interval of the bone fracture probability predictions. CONCLUSIONS: The reduction in uncertainty and improved confidence in bone fracture predictions increased the fidelity and credibility of the fracture risk model and its benefit to mission design and operational decisions.

  17. Osteoporotic Fracture Risk Assessment Using Bone Mineral Density in Korean: A Community-based Cohort Study

    PubMed Central

    Jang, Eun Jin; Lee, Young-Kyun; Choi, Hyung Jin

    2016-01-01

    Background Fracture-risk assessment tool (FRAX) using just clinical risk factors of osteoporosis has been developed to estimate individual risk of osteoporotic fractures. We developed prediction model of fracture risk using bone mineral density (BMD) as well as clinical risk factors in Korean, and assessed the validity of the final model. Methods To develop and validate an osteoporotic FRAX, a total of 768 Korean men and women aged 50 to 90 years were followed for 7 years in a community-based cohort study. BMD as well as clinical risk factors for osteoporotic fracture including age, sex, body mass index, history of fragility fracture, family history of fracture, smoking status, alcohol intake, use of oral glucocorticoid, rheumatoid arthritis, and other causes of secondary osteoporosis were assessed biannually. Results During the follow-up period, 86 osteoporotic fractures identified (36 in men and 50 in women). The developed prediction models showed high discriminatory power and had goodness of fit. Conclusions The developed a Korean specific prediction model for osteoporotic fractures can be easily used as a screening tool to identify individual with high risk of osteoporotic fracture. Further studies for validation are required to confirm the clinical feasibility in general Korean population. PMID:26981519

  18. Evaluation of the lateral orbital approach in management of zygomatic bone fractures

    PubMed Central

    Thangavelu, K; Ganesh, N Sayee; Kumar, J Arun; Sabitha, S; Nikil

    2013-01-01

    Zygomatic maxillary fractures, also known as tripod fractures, are usually the result of a direct blow to the body of the zygoma. Tripod fracture consists of (a) zygomatic arch fracture, (b) fracture of the lateral orbital wall, and (c) fracture of the inferior orbital floor. The purpose of this study is to evaluate the functional and esthetic outcome following this lateral orbital approach in the management of zygoma fracture. This study was carried out in VMS Dental College, Salem, and in a private hospital. This study was based on the experience gained from a retrospective study of the 30 lateral orbital approaches that were used in 30 patients with fractures of the zygomatic complex, which were conducted for a period of 8 years between January 2003 and January 2011. In the retrospective study, all the 30 patients were able to open the mouth completely; eyeball movements were normal; esthetically, all patients appeared normal. There were no sinusitis or visual problems in any of the studied patients. We conclude that the lateral orbital approach is an ideal option in reduction and treatment of zygomatic bone and arch fractures. PMID:23633846

  19. Non-osteoporotic women with low-trauma fracture present altered birefringence in cortical bone.

    PubMed

    Ascenzi, Maria-Grazia; Chin, Jesse; Lappe, Joan; Recker, Robert

    2016-03-01

    Areal bone mineral density (BMD) by DXA, although an important index, does not accurately assess risk of fragility fracture. Another bone structural parameter, the orientation of type I collagen, is known to add to risk determination, independently of BMD. Accordingly, we investigated the Haversian systems of transiliac crest biopsies from non-osteoporotic women with low-trauma fractures, matched to healthy women without fracture by age and BMD. We employed circularly polarized light (CPL) microscopy because 1) each of the extinct and bright birefringent signals of CPL corresponds to a specific collagen arrangement; and 2) CPL can employ magnification suitable to provide data, of manageable size, from the whole cortical component of a section of biopsy. Under CPL, the coaxial layers of osteons, called lamellae, appear either birefringent extinct or bright. On a section transverse to the Haversian system, the extinct lamella comprises mainly collagen forming small angles, and the bright lamella comprises mainly collagen forming large angles, relative to the general orientation of the Haversian system. We performed semi-automatic morphometry for birefringent and structural parameters for which we computed intra- and inter-observer errors. The statistical analysis used a linear mixed model to compare fracturing and non-fracturing groups while addressing pairing of fracturing and non-fracturing subjects, and linear regression to assess differences between matched subjects. We found significant reduction in 1) lamellar width and area for extinct lamella and bright lamella; 2) percentage of extinct birefringence in osteons, and 3) single osteon area; in the fracturing group; and in lamellar width in the fracturing subject of all pairs. Our results evidence the need to investigate, in a larger sample of subjects, the distribution of collagen orientation as a parameter diagnostic of increased fracture risk. PMID:26514952

  20. Pro-inflammatory cytokines and bone fractures in CKD patients. An exploratory single centre study

    PubMed Central

    2012-01-01

    Background Pro-inflammatory cytokines play a key role in bone remodeling. Inflammation is highly prevalent in CKD-5D patients, but the relationship between pro-inflammatory cytokines and fractures in CKD-5D patients is unclear. We studied the relationship between inflammatory cytokines and incident bone fractures in a cohort of CKD-5D patients. Methods In 100 CKD-5D patients (66 on HD, 34 on CAPD; males:63, females:37; mean age: 61 ± 15; median dialysis vintage: 43 months) belonging to a single renal Unit, we measured at enrolment bone metabolic parameters (intact PTH, bone and total alkaline phosphatase, calcium, phosphate) and inflammatory cytokines (TNF-α, IL-6, CRP). Patients were followed-up until the first non traumatic fracture. Results During follow-up (median: 74 months; range 0.5 -84.0) 18 patients experienced fractures. On categorical analysis these patients compared to those without fractures had significantly higher intact PTH (median: 319 pg/ml IQ range: 95–741 vs 135 pg/ml IQ: 53–346; p = 0.04) and TNF-α levels (median: 12 pg/ml IQ: 6.4-13.4 vs 7.8 pg/ml IQ: 4.6-11; p = 0.02). Both TNF-α (HR for 5 pg/ml increase in TNF-α: 1.62 95% CI: 1.05-2.50; p = 0.03) and intact PTH (HR for 100 pg/ml increase in PTH: 1.15 95% CI: 1.04-1.27; p = 0.005) predicted bone fractures on univariate Cox’s regression analysis. In restricted (bivariate) models adjusting for previous fractures, age, sex and other risk factors both PTH and TNF-α maintained an independent association with incident fractures. Conclusions In our bivariate analyses TNF-α was significantly associated with incident fractures. Analyses in larger cohorts and with adequate number of events are needed to firmly establish the TNF α -fracture link emerged in the present study. PMID:23043229

  1. Fracture resistance behaviour of gamma-irradiation sterilized cortical bone protected with a ribose pre-treatment

    NASA Astrophysics Data System (ADS)

    Woodside, Carman Mitchell

    Structural bone allograft reconstructions are often implemented to repair large skeletal defects. To ensure the biological safety of the patient, allograft material is routinely sterilized with gamma-irradiation prior to implantation. The sterilization process damages the tissue, specifically the collagen protein network, leading to severe losses in the mechanical properties of the bone. Our lab has begun developing a ribose pre-treatment that can protect bone from these harmful effects. The goals of the present study were to develop a method to measure the fracture toughness of bone, an important clinical failure mode, and implement it to determine the effectiveness of the ribose pre-treatment on fracture toughness. We have shown that the ribose pre-treatment is successful at protecting some of the original fracture toughness of sterilized bone, and that the connectivity of the collagen network is an important contributor to the fracture resistance of bone.

  2. The efficacy of calcitriol therapy in the management of bone loss and fractures: a qualitative review

    PubMed Central

    Hebl, S.; Purnell, J. Q.; Reid, M. E.; Rosier, R. N.; Mustian, K. M.; Palesh, O. G.; Huston, A. J.; Ling, M. N.; Morrow, G. R.

    2010-01-01

    Summary Osteoporosis, a skeletal disorder characterized by a reduction in bone strength, increases fracture risk. Primary osteoporosis is usually a result of reduced bone mineral density as a consequence of natural aging. Secondary osteoporosis is usually a result of a disease, such as cystic fibrosis, or medical treatment, such as corticosteroids or cancer treatment. Introduction Currently, ten million Americans are osteoporotic and an additional 34 million have the precursor condition, osteopenia. Osteoporosis leads to 1.5 million fractures and 500,000 hospitalizations annually. Osteoporosis-related fractures increase mortality and reduce quality of life. Calcitriol, the active form of vitamin D, regulates intestinal calcium absorption, among other actions. During the past four decades, many clinical trials investigating the effect of calcitriol on bone loss have been performed. Methods We conducted a systematic qualitative review of clinical trials that assessed calcitriol for the treatment of osteoporosis and bone loss. In these clinical trials, calcitriol was used as a monotherapy and in combination with other therapeutic bone agents. Results and conclusion Studies using calcitriol monotherapy, although not conclusive, found that calcitriol slowed the rate of bone loss in a variety of populations. Calcitriol in combination with other therapeutic bone agents was shown to have additional bone-preserving effects when compared to the use of therapeutic bone agents alone. A common side-effect of calcitriol therapy was hypercalcemia and hypercalciuria, but the degree of hypercalcemia was mild. Recent research found that intermittent dosing can reduce hypercalcemia rates. Calcitriol, alone or in combination with other agents, should be considered for the therapy of osteoporosis. PMID:19960185

  3. [Bone metastases or an insufficiency fracture? Oncology patients reporting pain or showing bone abnormalities on a scan].

    PubMed

    Meerveld-Eggink, Aafke; Bollen, Thomas L; Wijrdeman, Harm K; Los, Maartje

    2013-01-01

    A 71-year-old patient reported pain in the left hip 14 months after treatment with radiotherapy for a ypT3N1M0 rectal carcinoma, and a 61-year-old patient reported pain in the lower back with radiation to the buttocks 8 months after radiotherapy for a ypT3N2M0 rectal carcinoma. In both patients the initial diagnosis considered was bone metastasis. After MRI and nuclear bone scans, however, diagnoses of insufficiency fractures of the acetabulum and sacroiliac (SI) joints, respectively, were made. Insufficiency fractures of the SI joints or acetabula are a frequent complication of radiotherapy and should be considered in all oncology patients who present with sudden onset of back pain or lower back pain after radiotherapy. A MRI scan is the initial investigation of choice. Treatment is conservative, with analgesia and physiotherapy. Prognosis is good; symptoms disappear within 1 year in almost all patients. PMID:23841929

  4. Open Fracture of the Forearm Bones due to Horse Bite

    PubMed Central

    Santoshi, John Ashutosh; Leshem, Lall

    2014-01-01

    Introduction: Fractures have been described mainly following falling accidents in horse-related injuries. Horse bites are uncommon accidents. We present a case of open fracture of the forearm due to horse bite. Case Report: A 35-year-old male farm-worker presented to the emergency room with alleged history of horse bite to the right forearm about 2 hours prior to presentation while feeding the horse. There was deformity of the forearm with multiple puncture wounds, deep abrasions and small lacerations on the distal-third of the forearm. Copious irrigation with normal saline was done and he was administered anti-tetanus and postexposure rabies prophylaxis. Prophylactic antibiotic therapy was commenced. Radiographs revealed fracture of radius and ulna in the mid-shaft region. He underwent emergency wound debridement, and the ulna was stabilised with an intra-medullary square nail. Seventy-two hours later, he underwent re-debridement and conversion osteosynthesis. He had an uneventful recovery and at three-month follow-up, the fractures had healed radiographically in anatomic alignment. At two-year follow-up, he is doing well, is pain free and has a normal range of motion compared to the contralateral side. Conclusion: Horse bites behave as compound fractures however rabies prophylaxis will be needed and careful observation is needed. Early radical debridement, preliminary skeletal stabilisation, re-debridement and conversion osteosynthesis to plate, and antibiotic prophylaxis were the key to the successful management of our patient.

  5. Osteosynthesis of ununited femoral neck fracture by internal fixation combined with iliac crest bone chips and muscle pedicle bone grafting

    PubMed Central

    Baksi, D D; Pal, A K; Baksi, D P

    2016-01-01

    Background: Ununited femoral neck fracture is seen commonly in developing countries due to delayed presentation or failure of primary internal fixation. Such fractures, commonly present with partial or total absorption of femoral neck, osteonecrosis of femoral head in 8–30% cases with upward migration of trochanter posing problem for osteosynthesis, especially in younger individuals. Several techniques for treatment of such conditions are described like osteotomies or nonvascularied cortical or cancellous bone grafting provided varying degrees of success in terms of fracture union but unsatisfactory long term results occurred due to varying incidence of avascular necrosis (AVN) of femoral head. Moreover, in presence of AVN of femoral head neither free fibular graft nor cancellous bone graft is satisfactory. The vascularied bone grafting by deep circumflex iliac artery based on iliac crest bone grafting, free vascularied fibular grafting and muscle pedicle periosteal grafting showed high incidence of success rate. Osteosynthesis is the preferred treatment of choice in ununited femoral neck fracture in younger individuals. Materials and Methods: Of the 293 patients operated during the period from June 1977 to June 2009, 42 were lost to followup. Seven patients with gluteus medius muscle pedicle bone grafting (MPBG) were excluded. Thus, out of 244 patients, 208 (85.3%) untreated nonunion and 36 (14.7%) following failure of primary internal fixation were available for studies. Time interval between the date of injury and operation in untreated nonunion cases was mean 6.5 months and in failed internal fixation cases was mean 11.2 months. Ages of the patients varied from 16 to 55 years. Seventy patients had partial and 174 had subtotal absorption of the femoral neck. Evidence of avascular necrosis (AVN) femoral head was found histologically in 135 (54.3%) and radiologically in 48 (19.7%) patients. The patients were operated by open reduction of fracture, cannulated hip

  6. Accelerated bone mineral loss following a hip fracture: a prospective longitudinal study.

    PubMed

    Dirschl, D R; Henderson, R C; Oakley, W C

    1997-07-01

    The purpose of this prospective study was to monitor the bone mineral density (BMD) of the lumbar spine and contralateral femoral neck in the first year following an osteoporosis-related fracture of the hip. Eighty-three elderly patients (mean age 77 years) who had sustained a hip fracture had determinations of BMD made at the time of fracture; 49 of these patients were available for reassessment of BMD 1 year later. The change in BMD was correlated with pre- and postinjury variables, such as ambulatory ability, dietary intake of calcium, serum vitamin D levels, mental status, and routine serologies. The mean decrease in BMD in the year following fracture was 5.4% from the contralateral femoral neck and 2.4% from the lumbar spine. Calcium intake correlated with the loss of BMD from the femoral neck (p = 0.015), but not the lumbar spine. Patients with daily calcium intakes of less than 500 mg/day had a more than 10% decrease in femoral neck BMD in the year following their hip fracture. Serum 1,25-dihydroxy vitamin D level correlated with loss of MBD from the lumbar spine (p = 0.001), but not from the femoral neck. There was no correlation between the loss of bone mineral from either measurement site and age, sex, level of ambulation, or mental status. The loss of BMD from the femoral neck in the year following a hip fracture is more than five times that reported in the nonfractured population. This accelerated rate of loss can have drastic consequences in an elderly population already exhibiting osteopenia and propensity to fall. Investigation of pharmacologic or other interventions in the first critical year following a hip fracture may potentially blunt this accelerated rate of bone loss and lessen the risk of subsequent fractures. PMID:9213011

  7. Compressive fatigue and fracture toughness behavior of injectable, settable bone cements.

    PubMed

    Harmata, Andrew J; Uppuganti, Sasidhar; Granke, Mathilde; Guelcher, Scott A; Nyman, Jeffry S

    2015-11-01

    Bone grafts used to repair weight-bearing tibial plateau fractures often experience cyclic loading, and there is a need for bone graft substitutes that prevent failure of fixation and subsequent morbidity. However, the specific mechanical properties required for resorbable grafts to optimize structural compatibility with native bone have yet to be established. While quasi-static tests are utilized to assess weight-bearing ability, compressive strength alone is a poor indicator of in vivo performance. In the present study, we investigated the effects of interfacial bonding on material properties under conditions that re-capitulate the cyclic loading associated with weight-bearing fractures. Dynamic compressive fatigue properties of polyurethane (PUR) composites made with either unmodified (U-) or polycaprolactone surface-modified (PCL-) 45S5 bioactive glass (BG) particles were compared to a commercially available calcium sulfate and phosphate-based (CaS/P) bone cement at physiologically relevant stresses (5-30 MPa). Fatigue resistance of PCL-BG/polymer composite was superior to that of the U-BG/polymer composite and the CaS/P cement at higher stress levels for each of the fatigue failure criteria, related to modulus, creep, and maximum displacement, and was comparable to human trabecular bone. Steady state creep and damage accumulation occurred during the fatigue life of the PCL-BG/polymer and CaS/P cement, whereas creep of U-BG/polymer primarily occurred at a low number of loading cycles. From crack propagation testing, fracture toughness or resistance to crack growth was significantly higher for the PCL-BG composite than for the other materials. Finally, the fatigue and fracture toughness properties were intermediate between those of trabecular and cortical bone. These findings highlight the potential of PCL-BG/polyurethane composites as weight-bearing bone grafts. PMID:26282077

  8. Hedgehog signaling mediates woven bone formation and vascularization during stress fracture healing.

    PubMed

    Kazmers, Nikolas H; McKenzie, Jennifer A; Shen, Tony S; Long, Fanxin; Silva, Matthew J

    2015-12-01

    Hedgehog (Hh) signaling is critical in developmental osteogenesis, and recent studies suggest it may also play a role in regulating osteogenic gene expression in the post-natal setting. However, there is a void of studies directly assessing the effect of Hh inhibition on post-natal osteogenesis. This study utilized a cyclic loading-induced ulnar stress fracture model to evaluate the hypothesis that Hh signaling contributes to osteogenesis and angiogenesis during stress fracture healing. Immediately prior to loading, adult rats were given GDC-0449 (Vismodegib - a selective Hh pathway inhibitor; 50mg/kg orally twice daily), or vehicle. Hh signaling was upregulated in response to stress fracture at 3 days (Ptch1, Gli1 expression), and was markedly inhibited by GDC-0449 at 1 day and 3 days in the loaded and non-loaded ulnae. GDC-0449 did not affect Hh ligand expression (Shh, Ihh, Dhh) at 1 day, but decreased Shh expression by 37% at 3 days. GDC-0449 decreased woven bone volume (-37%) and mineral density (-17%) at 7 days. Dynamic histomorphometry revealed that the 7 day callus was composed predominantly of woven bone in both groups. The observed reduction in woven bone occurred concomitantly with decreased expression of Alpl and Ibsp, but was not associated with differences in early cellular proliferation (as determined by callus PCNA staining at 3 days), osteoblastic differentiation (Osx expression at 1 day and 3 days), chondrogenic gene expression (Acan, Sox9, and Col2α1 expression at 1 day and 3 days), or bone resorption metrics (callus TRAP staining at 3 days, Rankl and Opg expression at 1 day and 3 days). To evaluate angiogenesis, vWF immunohistochemistry showed that GDC-0449 reduced fracture callus blood vessel density by 55% at 3 days, which was associated with increased Hif1α gene expression (+30%). Dynamic histomorphometric analysis demonstrated that GDC-0449 also inhibited lamellar bone formation. Lamellar bone analysis of the loaded limb (directly adjacent

  9. Vitamin A: Is it a risk factor for Osteoporosis and bone fracture?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Results from observational studies of the association between vitamin A intake or serum retinol concentration and bone mineral density or fracture are mixed. However, serum retinol is a poor measure of vitamin A status as it is subject to homeostatic control over a wide physiologic range of hepatic...

  10. Projection-reflection ultrasound images using PE-CMOS sensor: a preliminary bone fracture study

    NASA Astrophysics Data System (ADS)

    Lo, Shih-Chung B.; Liu, Chu-Chuan; Freedman, Matthew T.; Mun, Seong-Ki; Kula, John; Lasser, Marvin E.; Lasser, Bob; Wang, Yue Joseph

    2008-03-01

    In this study, we investigated the characteristics of the ultrasound reflective image obtained by a CMOS sensor array coated with piezoelectric material (PE-CMOS). The laboratory projection-reflection ultrasound prototype consists of five major components: an unfocused ultrasound transducer, an acoustic beam splitter, an acoustic compound lens, a PE-CMOS ultrasound sensing array (Model I400, Imperium Inc. Silver Spring, MD), and a readout circuit system. The prototype can image strong reflective materials such as bone and metal. We found this projection-reflection ultrasound prototype is able to reveal hairline bone fractures with and without intact skin and tissue. When compared, the image generated from a conventional B-scan ultrasound on the same bone fracture is less observable. When it is observable with the B-scan system, the fracture or crack on the surface only show one single spot of echo due to its scan geometry. The corresponding image produced from the projection-reflection ultrasound system shows a bright blooming strip on the image clearly indicating the fracture on the surface of the solid material. Speckles of the bone structure are also observed in the new ultrasound prototype. A theoretical analysis is provided to link the signals as well as speckles detected in both systems.

  11. Facilitation of bone resorption activities in synovial lavage fluid patients with mandibular condyle fractures.

    PubMed

    Takano, H; Takahashi, T; Nakata, A; Nogami, S; Yusa, K; Kuwajima, S; Yamazaki, M; Fukuda, M

    2016-05-01

    The aim of this study was to investigate the bone resorption effect of the mediators delivered in joint cavity of patients with mandibular condyle fractures by detecting osteoclast markers using cellular biochemistry methods, and by analysing bone resorption activities via inducing osteoclast differentiation of the infiltrated cells from arthrocentesis. Sixteen joints in 10 patients with mandibular condyle fractures were evaluated. The control group consisted of synovial fluid (SF) samples from seven joints of four volunteers who had no clinical signs or symptoms involving the temporomandibular joint (TMJ) or disc displacement. We collected SF cells from all patients during therapeutic arthrocentesis. The infiltrating cells from TMJ SF were cultured, differentiated into tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like cells and examined bone resorption activities. We also investigated factors related to osteoclast induction of SF, using ELISA procedures. Osteoclast-like cells were induced from the SF cells obtained from all patients with condylar fractures. These multinucleated giant cells were positive for TRAP and actin, and had the ability to absorb dentin slices. The levels of macrophage colony-stimulating factor (M-CSF), prostaglandin E2 (PGE2), soluble form of receptor activator of nuclear factor kappa-B ligand (sRANKL) and osteoprotegerin (OPG), in SF samples from the patients, were significantly higher than in the controls. These findings indicate that bone resorption activities in SF from patients with mandibular condyle fractures were upregulated and may participate in the pathogenesis and wound healing. PMID:26946239

  12. Management of Infection After Intramedullary Nailing of Long Bone Fractures: Treatment Protocols and Outcomes

    PubMed Central

    Makridis, Kostas G; Tosounidis, Theodoros; Giannoudis, Peter V

    2013-01-01

    Implant related sepsis is a relatively unusual complication of intra-medullary nail fixation of long bone fractures. Depending on the extent of infection, timing of diagnosis and progress of fracture union, different treatment strategies have been developed. The aim of this review article is to collect and analyze the existing evidence about the incidence and management of infection following IM nailing of long bone fractures and to recommend treatment algorithms that could be valuable in everyday clinical practice. After searching the P u b M e d /Medline databases, 1270 articles were found related to the topic during the last 20 years. The final review included 28 articles that fulfilled the inclusion criteria. Only a few prospective studies exist to report on the management of infection following IM nailing of long-bone fractures. In general, stage I (early) infections only require antibiotic administration with/without debridement. Stage II (delayed) infections can be successfully treated with debridement, IM reaming, antibiotic nails, and administration of antibiotics. Infected non-unions are best treated with exchange nailing, antibiotic administration and when infection has been eradicated with graft implantation if it is needed. Debridement, exchange nailing and systemic administration of antibiotics is the best indication for stage III (late) infections, while stage III infected non-unions can successfully be treated with nail removal and Ilizarov frame, especially when large bone defects exist. PMID:23919097

  13. Goal-directed ultrasound in the detection of long-bone fractures

    NASA Technical Reports Server (NTRS)

    Marshburn, Thomas H.; Legome, Eric; Sargsyan, Ashot; Li, Shannon Melton James; Noble, Vicki A.; Dulchavsky, Scott A.; Sims, Carrie; Robinson, David

    2004-01-01

    BACKGROUND: New portable ultrasound (US) systems are capable of detecting fractures in the remote setting. However, the accuracy of ultrasound by physicians with minimal ultrasound training is unknown. METHODS: After one hour of standardized training, physicians with minimal US experience clinically evaluated patients presenting with pain and trauma to the upper arm or leg. The investigators then performed a long-bone US evaluation, recording their impression of fracture presence or absence. Results of the examination were compared with routine plain or computer aided radiography (CT). RESULTS: 58 patients were examined. The sensitivity and specificity of US were 92.9% and 83.3%, and of the physical examination were 78.6% and 90.0%, respectively. US provided improved sensitivity with less specificity compared with physical examination in the detection of fractures in long bones. CONCLUSION: Ultrasound scans by minimally trained clinicians may be used to rule out a long-bone fracture in patients with a medium to low probability of fracture.

  14. Bone turnover markers for early detection of fracture healing disturbances: A review of the scientific literature.

    PubMed

    Sousa, Cristina P; Dias, Isabel R; Lopez-Peña, Mónica; Camassa, José A; Lourenço, Paulo J; Judas, Fernando M; Gomes, Manuela E; Reis, Rui L

    2015-01-01

    Imaging techniques are the standard method for assessment of fracture healing processes. However, these methods are perhaps not entirely reliable for early detection of complications, the most frequent of these being delayed union and non-union. A prompt diagnosis of such disorders could prevent prolonged patient distress and disability. Efforts should be directed towards the development of new technologies for improving accuracy in diagnosing complications following bone fractures. The variation in the levels of bone turnover markers (BTMs) have been assessed with regard to there ability to predict impaired fracture healing at an early stage, nevertheless the conclusions of some studies are not consensual. In this article the authors have revised the potential of BTMs as early predictors of prognosis in adult patients presenting traumatic bone fractures but who did not suffer from osteopenia or postmenopausal osteoporosis. The available information from the different studies performed in this field was systematized in order to highlight the most promising BTMs for the assessment of fracture healing outcome. PMID:25993365

  15. Fracture bone healing and biodegradation of AZ31 implant in rats.

    PubMed

    Iglesias, C; Bodelón, O G; Montoya, R; Clemente, C; Garcia-Alonso, M C; Rubio, J C; Escudero, M L

    2015-04-01

    The ideal temporary implant should offer enough mechanical support to allow healing of the fracture and then biodegrade and be resorbed by metabolic mechanisms without causing any toxic effect. The aim of this research has been to simultaneously study in situ bone healing and the biodegradation of AZ31 Mg alloy as an osteosynthesis material. The in vivo study was carried out in AZ31 implants with and without Mg-fluoride coating inserted in un-fractured and fractured femurs of Wistar rats for long experimentation time, from 1 to 13 months, by means of computed tomography, histological and histomorphometric analysis. Tomography analysis showed the bone healing and biodegradation of AZ31 implants. The fracture is healed in 100% of the animals, and AZ31 maintains its mechanical integrity throughout the healing process. Biodegradation was monitored, quantifying the evolution of gas over time by 3D composition of tomography images. In all the studied groups, gas pockets disappear with time as a result of the diffusion process through soft tissues. Histomorphometric studies reveal that after 13 months the 46.32% of AZ31 alloy has been resorbed. The resorption of the coated and uncoated AZ31 implants inserted in fractured femurs after 1, 9 and 13 months does not have statistically significant differences. There is a balance between the biodegradation of AZ31 and bone healing which allows the use of AZ31 to be proposed as an osteosynthesis material. PMID:25886380

  16. Micro and nano MgO particles for the improvement of fracture toughness of bone-cement interfaces

    PubMed Central

    Khandaker, Morshed; Li, Yanling; Morris, Tracy

    2013-01-01

    The objective of this study was to determine whether inclusion of magnesium oxide (MgO) in micro and nanoparticulate forms in poly Methyl MethAcrylate (PMMA) cement has any influence on the fracture toughness of bone-cement interfaces. An interfacial fracture mechanics technique was used to compare the values of fracture toughness (KIC) among bone-PMMA, bone-PMMA with micro MgO particles and bone-PMMA with nano MgO particles interfaces. This study found that the values of KIC of bone-PMMA with micro MgO particles and bone–PMMA with nano MgO particles interfaces were significantly higher when compared to the values of KIC of the bone-PMMA interface (p<0.0001). Results indicated that the addition of the micro and nano MgO particles to PMMA improved the quality of bone-cement union. PMID:23332232

  17. Urinary Deoxypyridinoline Level Reveals Bone Resorption, Predicts Fracture Risk, And Enhances the Results of Dual Energy X-ray Absorptiometry.

    PubMed

    Kells, John; Dollbaum, Charles M

    2009-01-01

    Bone loss leads to an increased incidence of fracture and is associated with the development of osteoporosis, which can strike people of any age and afflicts 10 million individuals in the U.S. today. Research indicates that osteoporosis causes more than 1.5 million fractures annually, including approximately 300,000 fractures at other sites. Early detection of bone loss (resorption), like that revealed by a combination of dual energy X-ray absorptiometry and monitoring the level of deoxypyridinoline in urine, provides the most complete picture of long-term and short-term bone health. In this reports, we examine the effects of increased bone resorption and various methods of testing for bone loss, present findings from the literature on the effects of and monitorying for bone resorption, and profile individuals most likely to benefit from testing for a decrease in bone mass. PMID:23965324

  18. Finite element modeling for strain rate dependency of fracture resistance in compact bone.

    PubMed

    Charoenphan, S; Polchai, A

    2007-02-01

    Crack growths in compact bones driven by various strain rate levels were studied using finite element modeling. The energy resistance curves in bovine femur cortical bones were characterized, whereas the orthotropic viscoelasticity in bone materials was accounted for to assess the effect of strain rate on the energy resistance curve. The models were also used to justify the anticipated plane strain response as a result of rather thick specimens used in experiments. Similarities were found between the experimental and model results when crack resistance ability exhibited in bones with slow loading rates, while unstable crack growth existed in bones with rapid loading rates. The critical energy release rates slightly decreased with the increase in strain rates. The hybrid experimental and computational method introduced in this study could be beneficial for application in fracture study in which standard experiments cannot be validly performed. PMID:17227094

  19. Large bone distractor for open reconstruction of articular fractures of the calcaneus

    PubMed Central

    Twardosz, Wojciech; Tondel, Wieslaw; Olewicz-Gawlik, Anna; Hrycaj, Pawel

    2009-01-01

    The results of operative treatment of two groups of patients with articular fractures of the calcaneus were evaluated. Twenty-three cases were treated surgically using a standard reconstruction procedure. In the second group of 19 patients a large bone distractor was used; it held the soft tissue flap retracted, while aiding in articular and tuberosity fragment reduction and increasing visualisation by distraction of the posterior talocalcaneal joint. After a year, the anatomical and functional results, together with the operative time, were evaluated. All fractures healed with good or very good anatomical results. All cases, except those with complications (n = 3), achieved good (n = 28) or very good (n = 11) functional scoring. The distractor group had significantly shorter operative times, and less manpower was needed during surgery. We conclude that the large bone distractor is a useful tool in open reconstruction of articular calcaneal fractures. PMID:19404639

  20. Pediatric Obesity and Traumatic Lower Extremity Long Bone Fracture Outcomes

    PubMed Central

    Backstrom, Ian C.; MacLennan, Paul A.; Sawyer, Jeffrey R.; Creek, Aaron T.; Rue, Loring W.; Gilbert, Shawn R.

    2013-01-01

    Background Pediatric obesity is associated with lower extremity injuries and poor outcomes after blunt trauma. Our aim was to determine if obese pediatric patients with femur and tibia fractures have more severe injury patterns and worse outcomes compared to non-obese patients. Methods We performed a retrospective cohort study of obese and non-obese pediatric patients with femur or tibia fractures treated at two Level-1 trauma centers from 2004-2010. Patients weighing ≥ 95th percentile for age and gender were classified as obese. Patients were compared regarding demographics, Injury Severity Score (ISS), intra-abdominal, and orthopedic injuries. Outcomes included fracture treatment, orthopedic complications, ICU and hospital length of stay, ventilator days, and mortality. Results Of the 356 patients included in the study, 78 (21.9%) were obese and 278 (78.1%) were non-obese. Obese patients were older (9.9±3.7 vs. 8.8±3.9 years; p=0.0162), had a higher ISS (20.8±13.4 vs. 14.5±10.8; p=0.0002), and sustained more intra-abdominal solid organ (24.4% vs.13.5%; p=0.0200) and hollow viscus (3.9% vs. 0.0%; p=0.0105) injuries. They had more pelvic fractures (15.4% vs. 6.9%; p=0.0196), bilateral tibia fractures (8.0% vs. 0.0%; p=0.0332), and operatively-treated femur fractures (89.9% vs. 79.1%; p=0.0484). Adjusting for age, obese patients were more likely to be admitted to the ICU [relative risk (RR), 1.68; 95% confidence interval (CI), 1.10-2.55] and die in the hospital (RR, 3.45; 95% CI, 1.14-10.41). Adjusting for ISS, these associations were non-significant. Conclusions Obese patients with femur and tibia fractures have more severe injuries which may predispose them to greater inpatient morbidity and mortality than non-obese patients. PMID:22902734

  1. Osteoblast-derived WNT16 represses osteoclastogenesis and prevents cortical bone fragility fractures

    PubMed Central

    Movérare-Skrtic, Sofia; Henning, Petra; Liu, Xianwen; Nagano, Kenichi; Saito, Hiroaki; Börjesson, Anna E; Sjögren, Klara; Windahl, Sara H; Farman, Helen; Kindlund, Bert; Engdahl, Cecilia; Koskela, Antti; Zhang, Fu-Ping; Eriksson, Emma E; Zaman, Farasat; Hammarstedt, Ann; Isaksson, Hanna; Bally, Marta; Kassem, Ali; Lindholm, Catharina; Sandberg, Olof; Aspenberg, Per; Sävendahl, Lars; Feng, Jian Q; Tuckermann, Jan; Tuukkanen, Juha; Poutanen, Matti; Baron, Roland; Lerner, Ulf H; Gori, Francesca; Ohlsson, Claes

    2015-01-01

    The WNT16 locus is a major determinant of cortical bone thickness and nonvertebral fracture risk in humans. The disability, mortality and costs caused by osteoporosis-induced nonvertebral fractures are enormous. We demonstrate here that Wnt16-deficient mice develop spontaneous fractures as a result of low cortical thickness and high cortical porosity. In contrast, trabecular bone volume is not altered in these mice. Mechanistic studies revealed that WNT16 is osteoblast derived and inhibits human and mouse osteoclastogenesis both directly by acting on osteoclast progenitors and indirectly by increasing expression of osteoprotegerin (Opg) in osteoblasts. The signaling pathway activated by WNT16 in osteoclast progenitors is noncanonical, whereas the pathway activated in osteoblasts is both canonical and noncanonical. Conditional Wnt16 inactivation revealed that osteoblast-lineage cells are the principal source of WNT16, and its targeted deletion in osteoblasts increases fracture susceptibility. Thus, osteoblast-derived WNT16 is a previously unreported key regulator of osteoclastogenesis and fracture susceptibility. These findings open new avenues for the specific prevention or treatment of nonvertebral fractures, a substantial unmet medical need. PMID:25306233

  2. New miniplate for osteosynthesis of mandibular angle fractures designed to improve formation of new bone.

    PubMed

    Pituru, Teodora Silagieva; Bucur, Alexandru; Gudas, Claudiu; Pituru, Silviu-Mirel; Marius Dinca, Octavian

    2016-04-01

    The purpose of this article is to present the study of a new miniplate designed to keep the maximum strains developed in the cortical bone near the fracture line during accidental biting to values below the threshold causing bone resorption. Designed to offer maximum fracture stability with minimal implanted volume and patient intrusion, the design uses a novel approach to account for the effects of the distance from the fracture line to the nearest screws. Its geometry minimizes the peak forces that can develop during most cases of mandible biomechanical loadings. A three-dimensional (3D) osteosynthesis finite element model for a human mandible confirmed the operational effectiveness of the miniplate. It also provided numerical estimates for the strains and screw forces in the cortical surface during incisor bites with clinically relevant forces of 200 N. Two prototypes, 0.6 mm and 0.8 mm in thickness, were repeatedly tested on fractured sheep mandibles, fixed in a purpose-built jig, to loads up to 150% of the maximum forces developed by human patients. The tests indicated good fracture stability, and the proof tests carried for each of the two prototypes terminated at more than 350 N due to failure of the loading cable and respectively, secondary mandible fractures occurring away from the miniplate. PMID:26888464

  3. Osteoblast-derived WNT16 represses osteoclastogenesis and prevents cortical bone fragility fractures.

    PubMed

    Movérare-Skrtic, Sofia; Henning, Petra; Liu, Xianwen; Nagano, Kenichi; Saito, Hiroaki; Börjesson, Anna E; Sjögren, Klara; Windahl, Sara H; Farman, Helen; Kindlund, Bert; Engdahl, Cecilia; Koskela, Antti; Zhang, Fu-Ping; Eriksson, Emma E; Zaman, Farasat; Hammarstedt, Ann; Isaksson, Hanna; Bally, Marta; Kassem, Ali; Lindholm, Catharina; Sandberg, Olof; Aspenberg, Per; Sävendahl, Lars; Feng, Jian Q; Tuckermann, Jan; Tuukkanen, Juha; Poutanen, Matti; Baron, Roland; Lerner, Ulf H; Gori, Francesca; Ohlsson, Claes

    2014-11-01

    The WNT16 locus is a major determinant of cortical bone thickness and nonvertebral fracture risk in humans. The disability, mortality and costs caused by osteoporosis-induced nonvertebral fractures are enormous. We demonstrate here that Wnt16-deficient mice develop spontaneous fractures as a result of low cortical thickness and high cortical porosity. In contrast, trabecular bone volume is not altered in these mice. Mechanistic studies revealed that WNT16 is osteoblast derived and inhibits human and mouse osteoclastogenesis both directly by acting on osteoclast progenitors and indirectly by increasing expression of osteoprotegerin (Opg) in osteoblasts. The signaling pathway activated by WNT16 in osteoclast progenitors is noncanonical, whereas the pathway activated in osteoblasts is both canonical and noncanonical. Conditional Wnt16 inactivation revealed that osteoblast-lineage cells are the principal source of WNT16, and its targeted deletion in osteoblasts increases fracture susceptibility. Thus, osteoblast-derived WNT16 is a previously unreported key regulator of osteoclastogenesis and fracture susceptibility. These findings open new avenues for the specific prevention or treatment of nonvertebral fractures, a substantial unmet medical need. PMID:25306233

  4. Cigarette smoking decreases TGF-b1 serum concentrations after long bone fracture.

    PubMed

    Moghaddam, A; Weiss, S; Wölfl, C G; Schmeckenbecher, K; Wentzensen, A; Grützner, P A; Zimmermann, G

    2010-10-01

    TGF-b1 serum concentrations are considered to be one of the most promising markers of fracture healing. Previously, we demonstrated significant differences in the post-traumatic time courses of patients with timely and delayed fracture healing. The aim of this study was to evaluate possible differences in the serum concentrations of TGF-b1 in cigarette-smoking vs. non-smoking patients with timely and delayed fracture healing in order to understand pathophysiological pathways through which smoking impairs fracture healing.Serum samples were collected from 248 patients undergoing surgical treatment for long bone fractures within 1 year of surgery. Samples from 14 patients with atrophic-type delayed fracture healing were compared with 14 matched patients with normal bone healing. Each group included seven smokers and seven non-smokers. Post-operative serum concentrations were analysed at 1, 2, 4, 8, and 12 weeks as well as 1 year after surgery. The patients were monitored both clinically and radiologically for the entire duration of the study.All patients increased TGF-b1 serum concentrations after surgery. In patients with normal fracture healing, significantly higher TGF-b1 levels were observed in non-smokers (70 ng/ml) than in smokers(50 ng/ml) at the 4th week after surgery (p = 0.007). Also at the 4th week, in patients with delayed healing, significantly lower TGF-b1 levels were observed in smokers than in non-smokers (38 ng/ml vs.47 ng/ml, p = 0.021). However, no significant differences between non-smokers with delayed healing and smokers with normal healing (p = 0.151) were observed at the 4th week after surgery. TGF-b1 serum concentrations reached a plateau in all groups from the 6th to the 12th week after surgery, with a slight decrease observed in the final measurement taken 1 year after surgery.This study demonstrates that, after fracture, TGF-b1 serum concentrations are reduced by smoking,and this reduction is statistically significant during the 4th week

  5. The Efficacy of Transverse Fixation and Early Exercise in the Treatment of Fourth Metacarpal Bone Fractures

    PubMed Central

    Moon, Suk-Ho; Kim, Hak-Soo; Jung, Sung-No

    2016-01-01

    Background Several techniques have been designed to treat fifth metacarpal fractures reported to be effective. However, these methods cannot be easily applied to the fourth metacarpal due to its central anatomical position. In this study, we sought to analyze the functional outcomes of patients who underwent transverse pinning for a fourth metacarpal bone fracture. Methods A total of 21 patients were selected and their charts were retrospectively reviewed. After fracture reduction, two transverse Kirchner wires were first inserted from the fifth metacarpal to the third metacarpal transversely at the distal part of the fractured bone, and then another two wires were inserted at the proximal part of the fractured bone. The splint was removed approximately one week postoperatively and the Kirchner wires were removed four to five weeks postoperatively. Patients started active and passive exercise one week after the operation. Pain visual analog scores, total active and passive motion, and the active and passive range of motion of the metacarpophalangeal joint and grip strength were evaluated. Results Dorsal angulation improved from a preoperative value of 44.2° to a postoperative value of 5.9°. Six weeks after surgery, functional recovery parameters, such as range of motion and grip strength, had improved to 98% of the function of the normal side. No major complication was observed. Conclusions We suggest that the transverse pinning of fourth metacarpal bone fractures is an effective treatment option that is less invasive than other procedures, easy to perform, requires no secondary surgery, minimizes joint and soft tissue injury, and allows early mobilization. PMID:27019812

  6. Traumatic Periprosthetic Acetabular Fracture Treated with One-Stage Exchange and Bone Reconstruction Using a Synthetic Bone Graft Substitute

    PubMed Central

    2016-01-01

    A case of a traumatic periprosthetic acetabular fracture in an elderly patient, which was treated by one-stage hip exchange with implantation of an antiprotrusio cage and reconstruction of the acetabular bone loss with an injectable calcium sulphate/hydroxyapatite bone graft substitute, is reported. The paste-like bone graft substitute was injected through the holes of the antiprotrusio cage. After a setting time of 15 minutes, a low-profile cup was cemented onto the cage using polymethylmethacrylate and a new stem was inserted. The patient was encouraged to ambulate three days postoperatively weight-bearing as tolerated. At the one-year follow-up visit the patient was ambulatory and full weight-bearing without any walking aids. The follow-up radiographs demonstrated stable position and articulation of the revision hip arthroplasty with no signs of loosening of the antiprotrusio cage. However, the most interesting finding was that the bone graft substitute had remodelled to a great extent into bone. This calcium sulphate/hydroxyapatite composite shows high osteoconductive potential and can be used to regenerate bone stock in revision arthroplasty. PMID:27446621

  7. Traumatic Periprosthetic Acetabular Fracture Treated with One-Stage Exchange and Bone Reconstruction Using a Synthetic Bone Graft Substitute.

    PubMed

    Svacina, Jan

    2016-01-01

    A case of a traumatic periprosthetic acetabular fracture in an elderly patient, which was treated by one-stage hip exchange with implantation of an antiprotrusio cage and reconstruction of the acetabular bone loss with an injectable calcium sulphate/hydroxyapatite bone graft substitute, is reported. The paste-like bone graft substitute was injected through the holes of the antiprotrusio cage. After a setting time of 15 minutes, a low-profile cup was cemented onto the cage using polymethylmethacrylate and a new stem was inserted. The patient was encouraged to ambulate three days postoperatively weight-bearing as tolerated. At the one-year follow-up visit the patient was ambulatory and full weight-bearing without any walking aids. The follow-up radiographs demonstrated stable position and articulation of the revision hip arthroplasty with no signs of loosening of the antiprotrusio cage. However, the most interesting finding was that the bone graft substitute had remodelled to a great extent into bone. This calcium sulphate/hydroxyapatite composite shows high osteoconductive potential and can be used to regenerate bone stock in revision arthroplasty. PMID:27446621

  8. Bone tissue heterogeneity is associated with fracture toughness: a polarization Raman spectroscopy study

    NASA Astrophysics Data System (ADS)

    Makowski, Alexander J.; Granke, Mathilde; Uppuganti, Sasidhar; Mahadevan-Jansen, Anita; Nyman, Jeffry S.

    2015-02-01

    Polarization Raman Spectroscopy has been used to demonstrate microstructural features and collagen fiber orientation in human and mouse bone, concurrently measuring both organization and composition; however, it is unclear as to what extent these measurements explain the mechanical quality of bone. In a cohort of age and gender matched cadaveric cortical bone samples (23-101 yr.), we show homogeneity of both composition and structure are associated with the age related decrease in fracture toughness. 64 samples were machined into uniform specimens and notched for mechanical fracture toughness testing and polished for Raman Spectroscopy. Fingerprint region spectra were acquired on wet bone prior to mechanical testing by sampling nine different microstructural features spaced in a 750x750 μm grid in the region of intended crack propagation. After ASTM E1820 single edge notched beam fracture toughness tests, the sample was dried in ethanol and the osteonal-interstitial border of one osteon was samples in a 32x32 grid of 2μm2 pixels for two orthogonal orientations relative to the long bone axis. Standard peak ratios from the 9 separate microstructures show heterogeneity between structures but do not sufficiently explain fracture toughness; however, peak ratios from mapping highlight both lamellar contrast (ν1Phos/Amide I) and osteon-interstitial contrast (ν1Phos/Proline). Combining registered orthogonal maps allowed for multivariate analysis of underlying biochemical signatures. Image entropy and homogeneity metrics of single principal components significantly explain resistance to crack initiation and propagation. Ultimately, a combination of polarization content and multivariate Raman signatures allowed for the association of microstructural tissue heterogeneity with fracture resistance.

  9. Femoral head viability following hip fracture. Prognostic role of radionuclide bone imaging

    SciTech Connect

    Drane, W.E.; Rudd, T.G.

    1985-03-01

    A retrospective study was made of all radionuclide (RN) bone images performed at our institution over a two-year period to evaluate femoral head viability after nonpathologic fracture of the femoral neck. Twelve patients had avascular femoral heads during the perioperative period, of which nine had adequate follow-up. Seven of these nine patients had follow-up bone images. Revascularization occurred in four patients, while three had persistent absence of femoral head uptake. With clinical follow-up ranging from four to 29 months (median: 14 months), only two of these nine patients developed clinical or radiographic evidence of osteonecrosis. RN bone imaging performed in the perioperative period does not reliably predict the development of post-traumatic osteonecrosis of the femoral head and, at present, should not be used to determine prospectively method of treatment of femoral neck fracture.

  10. Nonenzymatic Glycation and Degree of Mineralization Are Higher in Bone From Fractured Patients With Type 1 Diabetes Mellitus.

    PubMed

    Farlay, Delphine; Armas, Laura A G; Gineyts, Evelyne; Akhter, Mohammed P; Recker, Robert R; Boivin, Georges

    2016-01-01

    Low-energy fractures are frequent complications in type 1 diabetes mellitus patients (T1DM). Modifications of bone intrinsic composition might be a potential cause of fragility observed in diabetic subjects. Advanced glycation end products (AGEs) were found in numerous connective tissues from T1DM patients. However, whether AGEs are present at high levels in bone matrix from diabetic subjects is unknown. Moreover, whether elevated AGEs in the bone matrix impair mineralization has not been addressed in humans. The purposes of this study were 1) to determine whether bone matrix from fracturing and nonfracturing T1DM contained more AGEs than bone from healthy patients (CTL), and 2) to compare the degree of mineralization of bone and hardness between fracturing and nonfracturing T1DM versus CTL. We analyzed iliac crest bone biopsies from 5 fracturing T1DM patients, 5 nonfracturing T1DM patients, and 5 healthy subjects, all age- and sex-matched. AGEs (pentosidine) in bone matrix was measured by high-performance liquid chromatography separately in trabecular and cortical bone. The degree of mineralization of bone (DMB) was assessed by digitized microradiography, and mechanical properties by micro- and nanohardness tests. Trabecular bone from fracturing T1DM exhibited significantly higher levels of pentosidine than CTL (p = 0.04) and was more mineralized than nonfracturing T1DM (p = 0.04) and CTL (p = 0.04). Trabecular bone was not significantly different in pentosidine between nonfracturing T1DM and CTL. Cortical bone from nonfracturing T1DM was not significantly different from CTL. Positive correlations were found between HbA1c and pentosidine (r' = 0.79, p < 0.003) and between HbA1c and DMB (r' = 0.64, p < 0.02). Both modifications could lead to less flexible bone (reduced modulus of elasticity) and a tendency toward low-energy fractures in T1DM patients. PMID:26234180

  11. The Usefulness of the Endonasal Incisional Approach for the Treatment of Nasal Bone Fracture

    PubMed Central

    Kim, Hyo Seong; Suh, Hyeun Woo; Ha, Ki Young; Kim, Boo Yeong

    2012-01-01

    Background Among all facial fractures, nasal bone fractures are the most common, and they have been reduced by closed reduction (CR) for a long time. But several authors have reported suboptimal results when using CR, and the best method of nasal bone reduction is still being debated. We have found that indirect open reduction (IOR) through an endonasal incisional approach is a useful method for more accurate reduction of the nasal bone. Methods A retrospective chart review was performed of 356 patients who underwent reduction of a nasal bone fracture in our department from January, 2006, to July, 2011. We treated 263 patients with IOR. We assessed patients' and doctors' satisfaction with surgical outcomes after IOR or CR. We evaluated the frequency of nasal bleeding owing to mucosal injury, and followed the surgical outcomes of patients who had simultaneous dorsal augmentation rhinoplasty. Results According to the analysis of the satisfaction scores, both patients and doctors were significantly more satisfied in the IOR group than the CR group (P<0.05). Mucosal injury with nasal bleeding occurred much less in the IOR group (5.3%) than the CR group (12.9%). Dorsal augmentation rhinoplasty with IOR was performed simultaneously in 34 cases. Most of them (31/34) showed satisfaction with the outcomes. Conclusions IOR enables surgeons to manipulate the bony fragment directly through the endonasal incisional approach. However, we propose that CR is the proper technique for patients under 16 and for those with comminuted nasal bone fractures because submucosal dissection in IOR can damage the growth or circulation of nasal bone. PMID:22783528

  12. Oxygen as a critical determinant of bone fracture healing-a multiscale model.

    PubMed

    Carlier, Aurélie; Geris, Liesbet; van Gastel, Nick; Carmeliet, Geert; Van Oosterwyck, Hans

    2015-01-21

    A timely restoration of the ruptured blood vessel network in order to deliver oxygen and nutrients to the fracture zone is crucial for successful bone healing. Indeed, oxygen plays a key role in the aerobic metabolism of cells, in the activity of a myriad of enzymes as well as in the regulation of several (angiogenic) genes. In this paper, a previously developed model of bone fracture healing is further improved with a detailed description of the influence of oxygen on various cellular processes that occur during bone fracture healing. Oxygen ranges of the cell-specific oxygen-dependent processes were established based on the state-of-the art experimental knowledge through a rigorous literature study. The newly developed oxygen model is compared with previously published experimental and in silico results. An extensive sensitivity analysis was also performed on the newly introduced oxygen thresholds, indicating the robustness of the oxygen model. Finally, the oxygen model was applied to the challenging clinical case of a critical sized defect (3mm) where it predicted the formation of a fracture non-union. Further model analyses showed that the harsh hypoxic conditions in the central region of the callus resulted in cell death and disrupted bone healing thereby indicating the importance of a timely vascularization for the successful healing of a large bone defect. In conclusion, this work demonstrates that the oxygen model is a powerful tool to further unravel the complex spatiotemporal interplay of oxygen delivery, diffusion and consumption with the several healing steps, each occurring at distinct, optimal oxygen tensions during the bone repair process. PMID:25452136

  13. Recent Update in the Diagnosis and Treatment of Bone Frailty in Patients with a Distal Radius Fracture.

    PubMed

    Shin, Young Ho; Gong, Hyun Sik

    2016-10-01

    Distal radius fracture (DRF) is the most common upper extremity fracture in the elderly. Patients with a DRF have a two to fourfold higher risk of a subsequent fracture than those with no history of fractures, and DRFs occur on average 15 years earlier than hip fractures. Therefore, patients with a DRF offer physicians an important opportunity to diagnose and treat osteoporosis to prevent a secondary fracture. In this review, we provide recent update in the diagnosis and treatment of bone frailty in patients with a DRF. PMID:27595946

  14. Fractal lacunarity of trabecular bone and magnetic resonance imaging: New perspectives for osteoporotic fracture risk assessment

    PubMed Central

    Zaia, Annamaria

    2015-01-01

    Osteoporosis represents one major health condition for our growing elderly population. It accounts for severe morbidity and increased mortality in postmenopausal women and it is becoming an emerging health concern even in aging men. Screening of the population at risk for bone degeneration and treatment assessment of osteoporotic patients to prevent bone fragility fractures represent useful tools to improve quality of life in the elderly and to lighten the related socio-economic impact. Bone mineral density (BMD) estimate by means of dual-energy X-ray absorptiometry is normally used in clinical practice for osteoporosis diagnosis. Nevertheless, BMD alone does not represent a good predictor of fracture risk. From a clinical point of view, bone microarchitecture seems to be an intriguing aspect to characterize bone alteration patterns in aging and pathology. The widening into clinical practice of medical imaging techniques and the impressive advances in information technologies together with enhanced capacity of power calculation have promoted proliferation of new methods to assess changes of trabecular bone architecture (TBA) during aging and osteoporosis. Magnetic resonance imaging (MRI) has recently arisen as a useful tool to measure bone structure in vivo. In particular, high-resolution MRI techniques have introduced new perspectives for TBA characterization by non-invasive non-ionizing methods. However, texture analysis methods have not found favor with clinicians as they produce quite a few parameters whose interpretation is difficult. The introduction in biomedical field of paradigms, such as theory of complexity, chaos, and fractals, suggests new approaches and provides innovative tools to develop computerized methods that, by producing a limited number of parameters sensitive to pathology onset and progression, would speed up their application into clinical practice. Complexity of living beings and fractality of several physio-anatomic structures suggest

  15. The new concept of the monitoring and appraisal of bone union inflexibility of fractures treated by Dynastab DK external fixator.

    PubMed

    Lenz, Gerhard P; Stasiak, Andrzej; Deszczyński, Jarosław; Karpiński, Janusz; Stolarczyk, Artur; Ziółkowski, Marcin; Szczesny, Grzegorz

    2003-10-30

    Background. This work focuses on problems of heuristic techniques based on artificial intelligence. Mainly about artificial non-linear and multilayer neurons, which were used to estimate the bone union fractures treatment process using orthopaedic stabilizers Dynastab DK. Material and methods. The author utilizes computer software based on multilayer neuronal network systems, which allows to predict the curve of the bone union at early stages of therapy. The training of the neural net has been made on fifty six cases of bone fracture which has been cured by the Dynastab stabilizers DK. Using such trained net, seventeen fractures of long bones shafts were being examined on strength and prediction of the bone union as well. Results. Analyzing results, it should be underlined that mechanical properties of the bone union in the slot of fracture are changing in nonlinear way in function of time. Especially, major changes were observed during the forth month of the fracture treatment. There is strong correlation between measure number two and measure number six. Measure number two is more strict and in the matter of fact it refers to flexion, as well as the measure number six, to compression of the bone in the fracture slot. Conclusions. Consequently, deflection loads are especially hazardous for healing bone. The very strong correlation between real curves and predicted curves shows the correctness of the neuronal model. PMID:17679847

  16. Temporal bone fracture under lateral impact: biomechanical and macroscopic evaluation.

    PubMed

    Montava, Marion; Masson, Catherine; Lavieille, Jean-Pierre; Mancini, Julien; Soussan, Jerome; Chaumoitre, Kathia; Arnoux, Pierre-Jean

    2016-03-01

    This work was conducted to study biomechanical properties and macroscopic analysis of petrous fracture by lateral impact. Seven embalmed intact human cadaver heads were tested to failure using an electrohydraulic testing device. Dynamic loading was done at 2 m/s on temporal region with maximal deflection to 12 mm. Anthropometric and pathological data were determined by pretest and posttest computed tomography images, macroscopic evaluation, and anatomical dissection. Biomechanical data were obtained. Results indicated the head to have nonlinear structural response. The overall mean values of failure forces, deflections, stiffness, occipital, and frontal peak acceleration were 7.1 kN (±1.1), 9.1 mm (±1.8), 1.3 kN/mm (±0.4), 90.5 g (±22.5), and 65.4 g (±16), respectively. The seven lateral impacts caused fractures, temporal fractures in six cases. We observed very strong homogeneity for the biomechanical and pathological results between different trials in our study and between data from various experiments and our study. No statistical correlation was found between anthropometric, biomechanical, and pathological data. These data will assist in the development and validation of finite element models of head injury. PMID:26036776

  17. A bispecific antibody targeting sclerostin and DKK-1 promotes bone mass accrual and fracture repair

    PubMed Central

    Florio, Monica; Gunasekaran, Kannan; Stolina, Marina; Li, Xiaodong; Liu, Ling; Tipton, Barbara; Salimi-Moosavi, Hossein; Asuncion, Franklin J.; Li, Chaoyang; Sun, Banghua; Tan, Hong Lin; Zhang, Li; Han, Chun-Ya; Case, Ryan; Duguay, Amy N.; Grisanti, Mario; Stevens, Jennitte; Pretorius, James K.; Pacheco, Efrain; Jones, Heidi; Chen, Qing; Soriano, Brian D.; Wen, Jie; Heron, Brenda; Jacobsen, Frederick W.; Brisan, Emil; Richards, William G.; Ke, Hua Zhu; Ominsky, Michael S.

    2016-01-01

    Inhibition of the Wnt antagonist sclerostin increases bone mass in patients with osteoporosis and in preclinical animal models. Here we show increased levels of the Wnt antagonist Dickkopf-1 (DKK-1) in animals treated with sclerostin antibody, suggesting a negative feedback mechanism that limits Wnt-driven bone formation. To test our hypothesis that co-inhibition of both factors further increases bone mass, we engineer a first-in-class bispecific antibody with single residue pair mutations in the Fab region to promote efficient and stable cognate light–heavy chain pairing. We demonstrate that dual inhibition of sclerostin and DKK-1 leads to synergistic bone formation in rodents and non-human primates. Furthermore, by targeting distinct facets of fracture healing, the bispecific antibody shows superior bone repair activity compared with monotherapies. This work supports the potential of this agent both for treatment and prevention of fractures and offers a promising therapeutic approach to reduce the burden of low bone mass disorders. PMID:27230681

  18. A bispecific antibody targeting sclerostin and DKK-1 promotes bone mass accrual and fracture repair.

    PubMed

    Florio, Monica; Gunasekaran, Kannan; Stolina, Marina; Li, Xiaodong; Liu, Ling; Tipton, Barbara; Salimi-Moosavi, Hossein; Asuncion, Franklin J; Li, Chaoyang; Sun, Banghua; Tan, Hong Lin; Zhang, Li; Han, Chun-Ya; Case, Ryan; Duguay, Amy N; Grisanti, Mario; Stevens, Jennitte; Pretorius, James K; Pacheco, Efrain; Jones, Heidi; Chen, Qing; Soriano, Brian D; Wen, Jie; Heron, Brenda; Jacobsen, Frederick W; Brisan, Emil; Richards, William G; Ke, Hua Zhu; Ominsky, Michael S

    2016-01-01

    Inhibition of the Wnt antagonist sclerostin increases bone mass in patients with osteoporosis and in preclinical animal models. Here we show increased levels of the Wnt antagonist Dickkopf-1 (DKK-1) in animals treated with sclerostin antibody, suggesting a negative feedback mechanism that limits Wnt-driven bone formation. To test our hypothesis that co-inhibition of both factors further increases bone mass, we engineer a first-in-class bispecific antibody with single residue pair mutations in the Fab region to promote efficient and stable cognate light-heavy chain pairing. We demonstrate that dual inhibition of sclerostin and DKK-1 leads to synergistic bone formation in rodents and non-human primates. Furthermore, by targeting distinct facets of fracture healing, the bispecific antibody shows superior bone repair activity compared with monotherapies. This work supports the potential of this agent both for treatment and prevention of fractures and offers a promising therapeutic approach to reduce the burden of low bone mass disorders. PMID:27230681

  19. The Association between Metabolic Syndrome, Bone Mineral Density, Hip Bone Geometry and Fracture Risk: The Rotterdam Study

    PubMed Central

    Muka, Taulant; Trajanoska, Katerina; Kiefte-de Jong, Jessica C.; Oei, Ling; Uitterlinden, André G; Hofman, Albert; Dehghan, Abbas; Zillikens, M. Carola; Franco, Oscar H.; Rivadeneira, Fernando

    2015-01-01

    The association between metabolic syndrome (MS) and bone health remains unclear. We aimed to study the association between MS and hip bone geometry (HBG), femoral neck bone mineral density (FN-BMD), and the risk of osteoporosis and incident fractures. Data of 2040 women and 1510 men participants in the third visit (1997–1999) of the Rotterdam Study (RSI-3), a prospective population based cohort, were available (mean follow-up 6.7 years). MS was defined according to the recent harmonized definition. HBG parameters were measured at the third round visit whereas FN-BMD was assessed at the third round and 5 years later. Incident fractures were identified from medical registry data. After correcting for age, body mass index (BMI), lifestyle factors and medication use, individuals with MS had lower bone width (β = -0.054, P = 0.003), lower cortical buckling ratio (β = -0.81, P = 0.003) and lower odds of having osteoporosis (odds ratio =0.56, P = 0.007) in women but not in men. Similarly, MS was associated with higher FN-BMD only in women (β = 0.028, P=0.001). In the analyses of MS components, the glucose component (unrelated to diabetes status) was positively associated with FN-BMD in both genders (β = 0.016, P = 0.01 for women and β = 0.022, P = 0.004 for men). In men, waist circumference was inversely associated with FN-BMD (β = -0.03, P = 0.004). No association was observed with fracture risk in either sex. In conclusion, women with MS had higher FN-BMD independent of BMI. The glucose component of MS was associated with high FN-BMD in both genders, highlighting the need to preserve glycemic control to prevent skeletal complications. PMID:26066649

  20. Subgroup Variations in Bone Mineral Density Response to Zoledronic Acid After Hip Fracture

    PubMed Central

    Magaziner, Jay S; Orwig, Denise L; Lyles, Kenneth W; Nordsletten, Lars; Boonen, Steven; Adachi, Jonathan D; Recknor, Chris; Colón-Emeric, Cathleen S; Mesenbrink, Peter; Bucci-Rechtweg, Christina; Su, Guoqin; Johnson, Rasheeda; Pieper, Carl F

    2014-01-01

    Minimizing post-fracture bone loss is an important aspect of recovery from hip fracture, and determination of factors that affect bone mineral density (BMD) response to treatment after hip fracture may assist in the development of targeted therapeutic interventions. A post hoc analysis of the HORIZON Recurrent Fracture Trial was done to determine the effect of zoledronic acid (ZOL) on total hip (TH) and femoral neck (FN) BMD in subgroups with low-trauma hip fracture. A total of 2127 patients were randomized (1:1) to yearly infusions of ZOL 5 mg (n = 1065) or placebo (n = 1062) within 90 days of operation for low-trauma hip fracture. The 1486 patients with a baseline and at least one post-baseline BMD assessment at TH or FN (ZOL = 745, placebo = 741) were included in the analyses. Percentage change from baseline in TH and FN BMD was assessed at months 12 and 24 and compared across subgroups of hip fracture patients. Percentage change from baseline in TH and FN BMD at months 12 and 24 was greater (p < 0.05) in ZOL-treated patients compared with placebo in most subgroups. Treatment-by-subgroup interactions (p < 0.05) indicated that a greater effect on BMD was observed for TH BMD at month 12 in females, in patients in the lower tertile body mass index at baseline (≤22.6 kg/m2), and in patients with baseline FN BMD T-score of ≤ –2.5; for FN BMD in patients who received ZOL for >6 weeks post-surgery; and for TH and FN BMD in patients with a history of one or more prior fractures. All interactions were limited to the first 12 months after treatment with none observed for the 24-month comparisons. (Clinical trial registration number NCT00046254.) PMID:24839241

  1. Novel Intramedullary-Fixation Technique for Long Bone Fragility Fractures Using Bioresorbable Materials

    PubMed Central

    Nishizuka, Takanobu; Kurahashi, Toshikazu; Hara, Tatsuya; Hirata, Hitoshi; Kasuga, Toshihiro

    2014-01-01

    Almost all of the currently available fracture fixation devices for metaphyseal fragility fractures are made of hard metals, which carry a high risk of implant-related complications such as implant cutout in severely osteoporotic patients. We developed a novel fracture fixation technique (intramedullary-fixation with biodegradable materials; IM-BM) for severely weakened long bones using three different non-metallic biomaterials, a poly(l-lactide) (PLLA) woven tube, a nonwoven polyhydroxyalkanoates (PHA) fiber mat, and an injectable calcium phosphate cement (CPC). The purpose of this work was to evaluate the feasibility of IM-BM with mechanical testing as well as with an animal experiment. To perform mechanical testing, we fixed two longitudinal acrylic pipes with four different methods, and used them for a three-point bending test (N = 5). The three-point bending test revealed that the average fracture energy for the IM-BM group (PLLA + CPC + PHA) was 3 times greater than that of PLLA + CPC group, and 60 to 200 times greater than that of CPC + PHA group and CPC group. Using an osteoporotic rabbit distal femur incomplete fracture model, sixteen rabbits were randomly allocated into four experimental groups (IM-BM group, PLLA + CPC group, CPC group, Kirschner wire (K-wire) group). No rabbit in the IM-BM group suffered fracture displacement even under full weight bearing. In contrast, two rabbits in the PLLA + CPC group, three rabbits in the CPC group, and three rabbits in the K-wire group suffered fracture displacement within the first postoperative week. The present work demonstrated that IM-BM was strong enough to reinforce and stabilize incomplete fractures with both mechanical testing and an animal experiment even in the distal thigh, where bone is exposed to the highest bending and torsional stresses in the body. IM-BM can be one treatment option for those with severe osteoporosis. PMID:25111138

  2. Assessment of the effect of reduced compositional heterogeneity on fracture resistance of human cortical bone using finite element modeling.

    PubMed

    Demirtas, Ahmet; Curran, Erin; Ural, Ani

    2016-10-01

    The recent reports of atypical femoral fracture (AFF) and its possible association with prolonged bisphosphonate (BP) use highlighted the importance of a thorough understanding of mechanical modifications in bone due to bisphosphonate treatment. The reduced compositional heterogeneity is one of the modifications in bone due to extensive suppression of bone turnover. Although experimental evaluations suggested that compositional changes lead to a reduction in the heterogeneity of elastic properties, there is limited information on the extent of influence of reduced heterogeneity on fracture resistance of cortical bone. As a result, the goal of the current study is to evaluate the influence of varying the number of unique elastic and fracture properties for osteons, interstitial bone, and cement lines on fracture resistance across seven different human cortical bone specimens using finite element modeling. Fracture resistance of seven human cortical bone samples under homogeneous and three different heterogeneous material levels was evaluated using a compact tension test setup. The simulation results predicted that the crack volume was the highest for the models with homogeneous material properties. Increasing heterogeneity resulted in a lower amount of crack volume indicating an increase in fracture resistance of cortical bone. This reduction was observed up to a certain level of heterogeneity after which further beneficial effects of heterogeneity diminished suggesting a possible optimum level of heterogeneity for the bone tissue. The homogeneous models demonstrated limited areas of damage with extensive crack formation. On the other hand, the heterogeneity in the material properties led to increased damage volume and a more variable distribution of damage compared to the homogeneous models. This resulted in uncracked regions which tended to have less damage accumulation preventing extensive crack propagation. The results also showed that the percent osteonal area

  3. Stress fractures of the sesamoid bones of the first metatarsophalangeal joint in athletes.

    PubMed

    Hulkko, A; Orava, S; Pellinen, P; Puranen, J

    1985-01-01

    Over a period of 11 years 15 cases of stress fractures of the sesamoid bones of the first metatarsophalangeal (MTP) joint were treated in athletes. The mean age of the patients was 22.3 years, and there were 9 males and 6 females in the series. All patients were athletes, who began to suffer from the symptoms during training without any trauma. Eight fractures were located in the medial, six in the lateral sesamoid bone, and in one case both sesamoids were affected. The diagnosis was performed on the basis of the history, symptoms, clinical examination, and radiological, or isotope scanning findings. Ten of the patients were treated conservatively by prescribing an avoidance of excessive physical activity and better training shoes. In five cases surgical excision of the fragmented painful sesamoid bone was performed. There were no complications in the series and the athletes could start gradually training 6-8 weeks after the operation. The histology showed fibrotic non-union at the fracture site and supported the diagnosis of stress fracture. Three of the conservatively treated athletes had mild symptoms in intensive training, others had a good end result. PMID:4051695

  4. Implant Augmentation: Adding Bone Cement to Improve the Treatment of Osteoporotic Distal Femur Fractures

    PubMed Central

    Wähnert, Dirk; Hofmann-Fliri, Ladina; Richards, R. Geoff; Gueorguiev, Boyko; Raschke, Michael J.; Windolf, Markus

    2014-01-01

    Abstract The increasing problems in the field of osteoporotic fracture fixation results in specialized implants as well as new operation methods, for example, implant augmentation with bone cement. The aim of this study was to determine the biomechanical impact of augmentation in the treatment of osteoporotic distal femur fractures. Seven pairs of osteoporotic fresh frozen distal femora were randomly assigned to either an augmented or nonaugmented group. In both groups, an Orthopaedic Trauma Association 33 A3 fractures was fixed using the locking compression plate distal femur and cannulated and perforated screws. In the augmented group, additionally, 1 mL of polymethylmethacrylate cement was injected through the screw. Prior to mechanical testing, bone mineral density (BMD) and local bone strength were determined. Mechanical testing was performed by cyclic axial loading (100 N to 750 N + 0.05N/cycle) using a servo-hydraulic testing machine. As a result, the BMD as well as the axial stiffness did not significantly differ between the groups. The number of cycles to failure was significantly higher in the augmented group with the BMD as a significant covariate. In conclusion, cement augmentation can significantly improve implant anchorage in plating of osteoporotic distal femur fractures. PMID:25415673

  5. Using bone's adaptation ability to lower the incidence of stress fractures.

    PubMed

    Milgrom, C; Simkin, A; Eldad, A; Nyska, M; Finestone, A

    2000-01-01

    In three prospective epidemiologic studies of the effect of pre-military-induction sport activities on the incidence of lower extremity stress fractures during infantry basic training, recruits who played ball sports (principally basketball) regularly for at least 2 years before basic training had a significantly lower incidence of stress fractures (13.2%, 16.7%, and 3.6% in the three studies, respectively) than recruits who did not play ball sports (28.9%, 27%, and 18.8%, respectively). Preinduction running was not related to the incidence of stress fracture. To assess the tibial strain environment during these sport activities, we made in vivo strain measurements on three male volunteers from the research team. Peak tibial compression and tension strain and strain rates during basketball reached levels 2 to 5.5 times higher than during walking and about 10% to 50% higher than during running. The high bone strain and strain rates that occurred in recruits while playing basketball in the years before military induction may have increased their bone stiffness, according to Wolff's Law. The stiffer bone could tolerate higher stresses better, resulting in lower strains for a given activity and a lower incidence of stress fractures during basic training. PMID:10751003

  6. Percutaneous Vertebral Augmentation with Polyethylene Mesh and Allograft Bone for Traumatic Thoracolumbar Fractures

    PubMed Central

    Schulz, C.; Kunz, U.; Mauer, U. M.; Mathieu, R.

    2015-01-01

    Purpose. In cases of traumatic thoracolumbar fractures, percutaneous vertebral augmentation can be used in addition to posterior stabilisation. The use of an augmentation technique with a bone-filled polyethylene mesh as a stand-alone treatment for traumatic vertebral fractures has not yet been investigated. Methods. In this retrospective study, 17 patients with acute type A3.1 fractures of the thoracic or lumbar spine underwent stand-alone augmentation with mesh and allograft bone and were followed up for one year using pain scales and sagittal endplate angles. Results. From before surgery to 12 months after surgery, pain and physical function improved significantly, as indicated by an improvement in the median VAS score and in the median pain and work scale scores. From before to immediately after surgery, all patients showed a significant improvement in mean mono- and bisegmental kyphoses. During the one-year period, there was a significant loss of correction. Conclusions. Based on this data a stand-alone approach with vertebral augmentation with polyethylene mesh and allograft bone is not a suitable therapy option for incomplete burst fractures for a young patient collective. PMID:25688302

  7. Comminuted long bone fractures in children. Could combined fixation improve the results?

    PubMed

    El-Alfy, Barakat; Ali, Ayman M; Fawzy, Sallam I

    2016-09-01

    Comminuted diaphyseal fractures in the pediatric age group represent a major orthopedic problem. It is associated with a high incidence of complications and poor outcomes because of the instability and difficulty in treatment. The aim of this study was to evaluate the efficacy of combined external skeletal fixation and flexible intramedullary nails in reconstruction of comminuted diaphyseal fracture in skeletally immature patients. Combined external fixator and elastic stable intramedullary nails were used in the management of 27 pediatric patients (15 males and 12 females) with unstable comminuted diaphyseal fractures of the tibia and femur. There were 19 fractures of the femur and eight fractures of the tibia. The average age of the patients was 8.7 years (range 7-14 years) for the femur and 10.8 years (range 6-15 years) for the tibia. Fractures were classified according to the system of Winquist and Hansen as grade II (five cases), grade III (nine cases), and grade IV (13 cases). All cases were operated within 6 days (range 0-6 days) after injury. The mean follow-up period was 2.8 years (range 2-3.5 years). The average duration of the external fixation was 1.6 months for fractures of the tibia, whereas it was 1.4 months for fractures of the femur. The average time for tibia fracture union was 2.8 months for fractures of the tibia, whereas it was 1.9 months for fractures of the femur. Malalignment in varus less than 5° was noted in one patient. One patient had a limb-length discrepancy of 1.5 cms. There were five cases (18.5%) with pin-tract infection. According to the Association for the Study and Application of the Methods of Ilizarov evaluation system, bone results were excellent in 23 cases (85.2%), good in three cases (11.1%), and poor in one case (3.7%). Functional results were excellent in 22 (81.5%) cases and good in five (18.5%) cases. Combined use of external fixators and elastic intramedullary nails is a good method for the treatment of comminuted

  8. Implantable microelectromechanical sensors for diagnostic monitoring and post-surgical prediction of bone fracture healing.

    PubMed

    McGilvray, Kirk C; Unal, Emre; Troyer, Kevin L; Santoni, Brandon G; Palmer, Ross H; Easley, Jeremiah T; Demir, Hilmi Volkan; Puttlitz, Christian M

    2015-10-01

    The relationship between modern clinical diagnostic data, such as from radiographs or computed tomography, and the temporal biomechanical integrity of bone fracture healing has not been well-established. A diagnostic tool that could quantitatively describe the biomechanical stability of the fracture site in order to predict the course of healing would represent a paradigm shift in the way fracture healing is evaluated. This paper describes the development and evaluation of a wireless, biocompatible, implantable, microelectromechanical system (bioMEMS) sensor, and its implementation in a large animal (ovine) model, that utilized both normal and delayed healing variants. The in vivo data indicated that the bioMEMS sensor was capable of detecting statistically significant differences (p-value <0.04) between the two fracture healing groups as early as 21 days post-fracture. In addition, post-sacrifice micro-computed tomography, and histology data demonstrated that the two model variants represented significantly different fracture healing outcomes, providing explicit supporting evidence that the sensor has the ability to predict differential healing cascades. These data verify that the bioMEMS sensor can be used as a diagnostic tool for detecting the in vivo course of fracture healing in the acute post-treatment period. PMID:26174472

  9. Characterization of Fatty Acid Composition in Bone Marrow Fluid From Postmenopausal Women: Modification After Hip Fracture.

    PubMed

    Miranda, Melissa; Pino, Ana María; Fuenzalida, Karen; Rosen, Clifford J; Seitz, Germán; Rodríguez, J Pablo

    2016-10-01

    Bone marrow adipose tissue (BMAT) is associated with low bone mass, although the functional consequences for skeletal maintenance of increased BMAT are currently unclear. BMAT might have a role in systemic energy metabolism, and could be an energy source as well as an endocrine organ for neighboring bone cells, releasing cytokines, adipokines and free fatty acids into the bone marrow microenvironment. The aim of the present report was to compare the fatty acid composition in the bone marrow supernatant fluid (BMSF) and blood plasma of postmenopausal women women (65-80 years old). BMSF was obtained after spinning the aspirated bone marrow samples; donors were classified as control, osteopenic or osteoporotic after dual-energy X-ray absorptiometry. Total lipids from human bone marrow fluid and plasma were extracted, converted to the corresponding methyl esters, and finally analyzed by a gas chromatographer coupled with a mass spectrometer. Results showed that fatty acid composition in BMSF was dynamic and distinct from blood plasma, implying significance in the locally produced lipids. The fatty acid composition in the BMSF was enriched in saturated fatty acid and decreased in unsaturated fatty acids as compared to blood plasma, but this relationship switched in women who suffered a hip fracture. On the other hand, there was no relationship between BMSF and bone mineral density. In conclusion, lipid composition of BMSF is distinct from the circulatory compartment, most likely reflecting the energy needs of the marrow compartment. J. Cell. Biochem. 117: 2370-2376, 2016. © 2016 Wiley Periodicals, Inc. PMID:27416518

  10. A linear-actuated torsional device to replicate clinically relevant spiral fractures in long bones.

    PubMed

    Edwards, W Brent; Troy, Karen L

    2012-09-01

    To better understand the mechanisms underlying spiral fracture we would like to carry out biomechanical tests of long bones loaded in torsion to failure. A device was fabricated to perform torsional tests of long bones using a single-axis linear actuator. The principal operation of the device was to transform the vertical displacement of a material testing machine's linear actuator into rotational movement using a spur gear and rack system. Accuracy and precision of the device were quantified using cast-acrylic rods with known torque-rotation behavior. Cadaveric experimentation was used to replicate a clinically relevant spiral fracture in eleven human proximal tibiae; strain-gage data were recorded for a single specimen. The device had an experimental error of less than 0.2 Nm and was repeatable to within 0.3%. Strain gage data were in line with those expected from pure torsion and the cadaveric tibiae illustrated spiral fractures at ultimate torque and rotation values of 130.6 +/- 53.2 Nm and 8.3 +/- 1.5 degrees, respectively. Ultimate torque was highly correlated with DXA assessed bone mineral density (r = 0.87; p < 0.00 1). The device presented is applicable to any torsional testing of long bone when only a single-axis linear actuator is available. PMID:23025174