Sample records for size tibial defects

  1. The effect of plate position and size on tibial slope in high tibial osteotomy: a cadaveric study.

    PubMed

    Rubino, L Joseph; Schoderbek, Robert J; Golish, S Raymond; Baumfeld, Joshua; Miller, Mark D

    2008-01-01

    Opening wedge high tibial osteotomies are performed for degenerative changes and varus. Opening wedge osteotomies can change proximal tibial slope in the sagittal plane, possibly imparting stability in the ACL-deficient knee. The aim of this study was to assess the effect of plate position and size on change in tibial slope. Eight cadaveric knees underwent opening wedge high tibial osteotomy with Puddu plates of each different size. Plates were placed anterior, central, and posterior for each size used. Lateral radiographs were obtained. Tibial slope was measured and compared with baseline slope. Tibial slope was affected by plate position (P < 0.05) and size (P < 0.001). Smaller, posterior plates had less effect on tibial slope. However, anterior and central plates increased tibial slope over all plate sizes (P < 0.05). This study found that tibial slope increases with opening wedge high tibial osteotomy. Larger corrections and anterior placement of the plate are associated with larger increases in slope.

  2. Flow-Through Free Fibula Osteocutaneous Flap in Reconstruction of Tibial Bone, Soft Tissue, and Main Artery Segmental Defects.

    PubMed

    Li, Zonghuan; Yu, Aixi; Qi, Baiwen; Pan, Zhenyu; Ding, Junhui

    2017-08-01

    The aim of this report was to present the use of flow-through free fibula osteocutaneous flap for the repair of complex tibial bone, soft tissue, and main artery segmental defects. Five patients with bone, soft tissue, and segmental anterior tibial artery defects were included. The lengths of injured tibial bones ranged from 4 to 7 cm. The sizes of impaired soft tissues were between 9 × 4 and 15 × 6 cm. The lengths of defect of anterior tibial artery segments ranged from 6 to 10 cm. Two patients had distal limb perfusion problems. Flow-through free fibula osteocutaneous flap was performed for all 5 patients. Patients were followed for 12 to 18 months. All wounds healed after 1-stage operation, and all flow-through flaps survived. The distal perfusion after vascular repair was normal in all patients. Superficial necrosis of flap edge was noted in 1 case. After the local debridement and partial thickness skin graft, the flap healed uneventfully, and the surgical operation did not increase injury to the donor site. Satisfactory bone union was achieved in all patients in 2 to 4 months postoperation. Enlargement of fibula graft was observed during follow-up from 12 to 18 months. The functions of adjacent joints were recovered, and all patients were able to walk normally. Flow-through free fibula osteocutaneous flap was shown to be an effective and efficient technique for repairing composite tibial bone, soft tissue, and main artery segmental defects. This 1-stage operation should be useful in clinical practice for the treatment of complex bone, soft tissue, and vessel defects.

  3. Tibial tunnel defect size as a risk factor in growth arrest following paediatric transphyseal anterior cruciate ligament reconstruction: an anatomical study.

    PubMed

    Pananwala, Hasitha; Jabbar, Yaser; Mills, Leonora; Symes, Michael; Nandapalan, Haren; Sefton, Andrew; Delungahawatte, Lasitha; Dao, Quang

    2016-09-01

    There is ongoing controversy regarding growth disturbances in younger patients undergoing anterior cruciate ligament reconstructions. Animal models have shown that an injury of 7-9% of the physeal area is a risk factor for growth disturbances. A total of 39 magnetic resonance imaging studies of the knee were examined. The proximal tibial physeal area was determined using a calibrated 'region of interest' ligature encompassing the tibial physis in the axial plane. The potential defect left by commonly used drill sizes was calculated as a percentage of the physeal area. A 7-mm drill leaves a mean defect of 1.45% physeal area (range: 1.11-1.89%, SD: 0.28, 95% CI: ±0.09), 8-mm drill leaves a 1.84% mean defect (range: 1.43-2.49%, SD: 0.38, 95% CI: ±0.12) and a 9-mm drill leaves a 2.30% mean defect (range: 1.83-3.19%, SD: 0.58, 95% CI: ±0.17). At 55°, 7-mm drill leaves a mean defect of 1.96% (range: 1.32-2.28%, SD: 0.37, 95% CI: ±0.12), 8-mm drill leaves a mean defect of 2.19% (range: 1.71-2.95%, SD: 0.46, 95% CI: ±0.14) and a 9-mm drill leaves a mean defect of 2.76% (range: 2.16-3.73%, SD: 0.58, 95% CI: ±0.18). There was a statistically significant difference in the tunnel area with a change of drill angle (7-mm drill P = 0.005, 8-mm drill P = 0.001, 9-mm drill P = 0.001). On the basis of this study in the context of animal model and observational evidence, the area of physeal injury using drill tunnels for anterior cruciate ligament reconstruction would not appear to contribute to potential growth disturbances. © 2016 Royal Australasian College of Surgeons.

  4. Ad hoc posterior tibial vessels perforator propeller flaps for the reconstruction of lower third leg soft- tissue defects.

    PubMed

    Balakrishnan, Thalaivirithan Margabandu; Ramkumar, Jayagosh; Jaganmohan, Janardhanan

    2017-01-01

    Lower third leg soft tissue defects with anatomical and pathological constraints are posing formidable challenges to reconstructive surgeon. This retrospective study was conducted to assess the effectiveness of ad hoc posterior tibial vessels perforator-propeller flaps for the reconstruction of small and medium sized soft tissue defects in the lower third leg. 22 patients (16 were males and 6 were females) were involved in this study between period of January 2012 and December 2016.We followed the protocol of initial non delineating exploratory incision made to find out single best perforator in all patients. All the defects in leg reconstructed with adhoc posterior tibial vessel propeller flaps. All 22 flaps survived well. All in an average of 13 months follow up period, had pain free walking, with minimal scarring and acceptable aesthesis at the reconstruction sites with no need for any secondary procedure. With inability of preoperatively dopplering the perforators in the lower third leg region, the exploratory posterior nondelineating incision was used in all cases to secure the single best perforator for the propeller flaps. Thus adhoc posterior tibial vessel propeller flaps are dependable, easily adoptable for the reconstruction of soft tissue defects of the lower third leg region.

  5. Ad hoc posterior tibial vessels perforator propeller flaps for the reconstruction of lower third leg soft- tissue defects

    PubMed Central

    Balakrishnan, Thalaivirithan Margabandu; Ramkumar, Jayagosh; Jaganmohan, Janardhanan

    2017-01-01

    Introduction: Lower third leg soft tissue defects with anatomical and pathological constraints are posing formidable challenges to reconstructive surgeon. Aim: This retrospective study was conducted to assess the effectiveness of ad hoc posterior tibial vessels perforator-propeller flaps for the reconstruction of small and medium sized soft tissue defects in the lower third leg. Patients and Methods: 22 patients (16 were males and 6 were females) were involved in this study between period of January 2012 and December 2016.We followed the protocol of initial non delineating exploratory incision made to find out single best perforator in all patients. All the defects in leg reconstructed with adhoc posterior tibial vessel propeller flaps. Results: All 22 flaps survived well. All in an average of 13 months follow up period, had pain free walking, with minimal scarring and acceptable aesthesis at the reconstruction sites with no need for any secondary procedure. Conclusion: With inability of preoperatively dopplering the perforators in the lower third leg region, the exploratory posterior nondelineating incision was used in all cases to secure the single best perforator for the propeller flaps. Thus adhoc posterior tibial vessel propeller flaps are dependable, easily adoptable for the reconstruction of soft tissue defects of the lower third leg region. PMID:29618863

  6. Computational modelling of ovine critical-sized tibial defects with implanted scaffolds and prediction of the safety of fixator removal.

    PubMed

    Doyle, Heather; Lohfeld, Stefan; Dürselen, Lutz; McHugh, Peter

    2015-04-01

    Computational model geometries of tibial defects with two types of implanted tissue engineering scaffolds, β-tricalcium phosphate (β-TCP) and poly-ε-caprolactone (PCL)/β-TCP, are constructed from µ-CT scan images of the real in vivo defects. Simulations of each defect under four-point bending and under simulated in vivo axial compressive loading are performed. The mechanical stability of each defect is analysed using stress distribution analysis. The results of this analysis highlights the influence of callus volume, and both scaffold volume and stiffness, on the load-bearing abilities of these defects. Clinically-used image-based methods to predict the safety of removing external fixation are evaluated for each defect. Comparison of these measures with the results of computational analyses indicates that care must be taken in the interpretation of these measures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Allografts with autogenous platelet-rich plasma for tibial defect reconstruction: a rabbit study.

    PubMed

    Nather, Aziz; Wong, Keng Lin; David, Vikram; Pereira, Barry P

    2012-12-01

    To evaluate the effect of autogenous platelet-rich plasma (PRP) for fresh-frozen allografts in tibial defect reconstruction in rabbits. 40 adult New Zealand white rabbits underwent tibial defect reconstruction with autografts (n=12), allografts without PRP (n=12), or allografts with PRP (n=12) and were observed for 12, 16, and 24 weeks (4 for each period). Tibias of the remaining 4 rabbits were used as donor allografts, and the remaining allografts were procured from recipient rabbits. A 1.5- cm cortical segment of the tibia was osteotomised, and then fixed with a 9-hole mini-compression plate and 2 cerclage wires. Allografts were stripped off the periosteum and soft tissues and medullary contents, and then stored in a freezer at -80 ºC. All allografts were deep frozen for at least 4 weeks before transplantation. 7 ml of whole blood was drawn to prepare 1 ml of PRP. The PRP was then mixed with 1.0 ml of human thrombin to form a platelet gel. The PRP gel was then packed into the medullary canal of the allograft and applied on the cortical surface before tibial defect reconstruction. Rabbits were sacrificed at 12, 16, and 24 weeks. The specimens were assessed for bone union at host-graft junctions and for bone resorption, new bone formation, callus encasement, and viable osteocyte counts. There were 4 specimens in each group at each observation period. Osteoid bridging the gap at host-graft junctions was noted in all specimens in the autograft and allograft-with-PRP groups at week 12 and in the allograft-without-PRP group at week 24. Bone union in allografts without PRP was delayed. All indices for biological incorporation (resorption index, new bone formation index, callus encasement index, and viable osteocyte count) were significantly greater in the autograft than allograft-without-PRP groups, except for the resorption index at week 24, whereas the differences were not significant between the autograft and allograft-with-PRP groups. The differences between the 2

  8. Treatment of large posttraumatic tibial bone defects using the Ilizarov method: a subjective outcome assessment.

    PubMed

    Krappinger, Dietmar; Irenberger, Alexander; Zegg, Michael; Huber, Burkhart

    2013-06-01

    The treatment of large posttraumatic tibial bone defects using the Ilizarov method was shown to be successful in several studies. These studies, however, typically focus on the radiological and functional outcome using objective parameters only. The aim of the present study was therefore to assess the objective and subjective outcome of a consecutive series of patients with large posttraumatic tibial bone defects using the Ilizarov method. Additionally, it was our goal to assess the physical and mental stress for the patients and their relatives during the long treatment period and the general health status at final follow-up. A consecutive series of 15 patients with posttraumatic tibial bone defects of >30 mm after sustaining open tibial fractures and failure of internal fixation was included. The objective outcome was assessed at final follow-up using Paley's criteria. For the assessment of the subjective outcome, all patients were asked to evaluate their satisfaction with the function of the lower leg, the cosmetic appearance and overall outcome as well. The physical and mental stress of the treatment for the patients and the nearest relative of patients were assessed at the time of frame removal using a custom-made questionnaire. The SF-36 was used to evaluate the general health status at final follow-up. Solid bone union with stable soft tissue coverage and eradication of infection was achieved in all patients despite a high complication rate. The functional outcome at final follow-up was excellent or good in all patients. The patients' satisfaction with the overall outcome and the function of the lower extremity was high as well. The fear of amputation and complications was the major subjective burden for both the patients and their relatives. The long external fixation time is another relevant issue. The Ilizarov method is a safe option for the treatment of large posttraumatic tibial bone defects after failure of internal fixation despite the high

  9. Higher Rate of Revision in PFC Sigma Primary Total Knee Arthroplasty With Mismatch of Femoro-Tibial Component Sizes.

    PubMed

    Young, Simon W; Clarke, Henry D; Graves, Stephen E; Liu, Yen-Liang; de Steiger, Richard N

    2015-05-01

    Total knee arthroplasty (TKA) systems permit a degree of femoro-tibial component size mismatch. The effect of mismatched components on revision rates has not been evaluated in a large study. We reviewed 21,906 fixed-bearing PFC Sigma primary TKAs using the Australian Orthopaedic Association National Joint Replacement Registry, dividing patients into three groups: no femoro-tibial size mismatch, tibial component size > femoral component size, and femoral component > tibial component. Revision rates were higher when the femoral size was greater than the tibia, compared to both equal size (HR = 1.20 (1.00, 1.45), P = 0.047) and to tibial size greater than femoral (HR = 1.60 (1.08, 2.37), P = 0.019). Potential mechanisms to explain these findings include edge loading of polyethylene and increased tibial component stresses. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. [Repairing of soft tissue defect in leg by free vascularized thoracoumbilical flap with reversed flow].

    PubMed

    Xu, Y Q; Li, Z Y; Li, J

    2000-11-01

    To investigate the clinical effect of free vascularized thoracoumbilical flap with reversal flow in repairing the soft tissue defect in leg with tibia exposure. Forty-four casting mould specimens of leg arteries were studied firstly. Then 25 cases with soft tissue defect and tibia exposure in the proximal-middle segment of leg were adopted in this study. Among them, 18 cases had long distance thrombosis of the anterior tibial vessels or posterior tibial vessels due to traumatic lesion. The maximal size of defect was 28 cm x 11 cm and the minimal size of defect was 11 cm x 9 cm. In operation, the thoracoumbilical flap which was based on the inferior epigastric vessels was anastomosed to the distal end of the anterior tibial vessels or posterior tibial vessels. Anterior tibial artery, posterior tibial artery and fibular artery had rich communication branches in foot and ankle. All the flaps survived, the color and cosmetic result of them were good. The free vascularized thoracoumbilical flap with reversed flow is practical in repairing the soft tissue defect of leg with tibia exposure. Either the anterior tibial vessels or the posterior tibial vessels is normal, and the distal end of injured blood vessels is available, this technique can be adopted.

  11. Segmental transports for posttraumatic lower extremity bone defects: are femoral bone transports safer than tibial?

    PubMed

    Liodakis, Emmanouil; Kenawey, Mohamed; Krettek, Christian; Ettinger, Max; Jagodzinski, Michael; Hankemeier, Stefan

    2011-02-01

    The long-term outcomes following femoral and tibial segment transports are not well documented. Purpose of the study is to compare the complication rates and life quality scores of femoral and tibial transports in order to find what are the complication rates of femoral and tibial monorail bone transports and if they are different? We retrospectively analyzed the medical records of 8 femoral and 14 tibial consecutive segment transports performed with the monorail technique between 2001 and 2008 in our institution. Mean follow-up was 5.1 ± 2.1 years with a minimum follow-up of 2 years. Aetiology of the defects was posttraumatic in all cases. Four femoral (50%) and nine tibial (64%) fractures were open. The Short Form-36 (SF-36) health survey was used to compare the life quality after femoral and tibial bone transports. The Mann-Whiney U test, Fisher exact test, and the Student's two tailed t-test were used for statistical analysis. P ≤ 0.05 was considered to be statistically significant. The tibial transport was associated with higher rates of severe complications and additional procedures (1.5 ± 0.9 vs. 3.4 ± 2.7, p = 0.048). Three patients of the tibial group were amputated because of recurrent infections and one developed a complete regenerate insufficiency that was treated with partial diaphyseal tibial replacement. Contrary to that none of patients of the femoral group developed a complete regenerate insufficiency or was amputated. Tibial bone transports have a higher rate of complete and incomplete regenerate insufficiency and can more often end in an amputation. The authors suggest systematic weekly controls of the CRP value and of the callus formation in patients with posttraumatic tibia bone transports. Further comparative studies comparing the results of bone transports with and without intramedullary implants are necessary.

  12. [Current treatment situation and progress on bone defect of collapsed tibial plateau fractures].

    PubMed

    Luo, Chang-qi; Fang, Yue; Tu, Chong-qi; Yang, Tian-fu

    2016-02-01

    Characteristics of collapsed tibial plateau fracture determines that the joint surface must remain anatomical reduction,line of force in tibial must exist and internal fixation must be strong. However, while renewing articular surface smoothness, surgeons have a lot of problems in dealing with bone defect under the joint surface. Current materials used for bone defect treatment include three categories: autologous bone, allograft bone and bone substitutes. Some scholars think that autologous bone grafts have a number of drawbacks, such as increasing trauma, prolonged operation time, the limited source, bone area bleeding,continuous pain, local infection and anesthesia,but most scholars believe that the autologous cancellous bone graft is still the golden standard. Allograft bone has the ability of bone conduction, but the existence of immune responses, the possibility of a virus infection, and the limited source of the allograft cannot meet the clinical demands. Likewise, bone substitutes have the problem that osteogenesis does not match with degradation in rates. Clinical doctors can meet the demand of the patient's bone graft according to patient's own situation and economic conditions.

  13. Osteogenic capacity of nanocrystalline bone cement in a weight-bearing defect at the ovine tibial metaphysis.

    PubMed

    Harms, Christoph; Helms, Kai; Taschner, Tibor; Stratos, Ioannis; Ignatius, Anita; Gerber, Thomas; Lenz, Solvig; Rammelt, Stefan; Vollmar, Brigitte; Mittlmeier, Thomas

    2012-01-01

    The synthetic material Nanobone(®) (hydroxyapatite nanocrystallines embedded in a porous silica gel matrix) was examined in vivo using a standardized bone defect model in the ovine tibial metaphysis. A standardized 6 × 12 × 24-mm bone defect was created below the articular surface of the medial tibia condyles on both hind legs of 18 adult sheep. The defect on the right side was filled with Nanobone(®), while the defect on the contralateral side was left empty. The tibial heads of six sheep were analyzed after 6, 12, and 26 weeks each. The histological and radiological analysis of the defect on the control side did not reveal any bone formation after the total of 26 weeks. In contrast, the microcomputed tomography analysis of the defect filled with Nanobone(®) showed a 55%, 72%, and 74% volume fraction of structures with bone density after 6, 12, and 26 weeks, respectively. Quantitative histomorphological analysis after 6, and 12 weeks revealed an osteoneogenesis of 22%, and 36%, respectively. Hematoxylin and eosin sections demonstrated multinucleated giant cells on the surface of the biomaterial and resorption lacunae, indicating osteoclastic resorptive activity. Nanobone(®) appears to be a highly potent bone substitute material with osteoconductive properties in a loaded large animal defect model, supporting the potential use of Nanobone(®) also in humans.

  14. Osteogenic capacity of nanocrystalline bone cement in a weight-bearing defect at the ovine tibial metaphysis

    PubMed Central

    Harms, Christoph; Helms, Kai; Taschner, Tibor; Stratos, Ioannis; Ignatius, Anita; Gerber, Thomas; Lenz, Solvig; Rammelt, Stefan; Vollmar, Brigitte; Mittlmeier, Thomas

    2012-01-01

    The synthetic material Nanobone® (hydroxyapatite nanocrystallines embedded in a porous silica gel matrix) was examined in vivo using a standardized bone defect model in the ovine tibial metaphysis. A standardized 6 × 12 × 24-mm bone defect was created below the articular surface of the medial tibia condyles on both hind legs of 18 adult sheep. The defect on the right side was filled with Nanobone®, while the defect on the contralateral side was left empty. The tibial heads of six sheep were analyzed after 6, 12, and 26 weeks each. The histological and radiological analysis of the defect on the control side did not reveal any bone formation after the total of 26 weeks. In contrast, the microcomputed tomography analysis of the defect filled with Nanobone® showed a 55%, 72%, and 74% volume fraction of structures with bone density after 6, 12, and 26 weeks, respectively. Quantitative histomorphological analysis after 6, and 12 weeks revealed an osteoneogenesis of 22%, and 36%, respectively. Hematoxylin and eosin sections demonstrated multinucleated giant cells on the surface of the biomaterial and resorption lacunae, indicating osteoclastic resorptive activity. Nanobone® appears to be a highly potent bone substitute material with osteoconductive properties in a loaded large animal defect model, supporting the potential use of Nanobone® also in humans. PMID:22745551

  15. Effect of interstitial low level laser therapy on tibial defect

    NASA Astrophysics Data System (ADS)

    Lee, Sangyeob; Ha, Myungjin; Hwang, Donghyun; Yu, Sungkon; Jang, Seulki; Park, Jihoon; Radfar, Edalat; Kim, Hansung; Jung, Byungjo

    2016-03-01

    Tibial defect is very common musculoskeletal disorder which makes patient painful and uncomfortable. Many studies about bone regeneration tried to figure out fast bone healing on early phase. It is already known that low level laser therapy (LLLT) is very convenient and good for beginning of bone disorder. However, light scattering and absorption obstruct musculoskeletal therapy which need optimal photon energy delivery. This study has used an interstitial laser probe (ILP) to overcome the limitations of light penetration depth and scattering. Animals (mouse, C57BL/6) were divided into three groups: laser treated test group 1 (660 nm; power 10 mW; total energy 5 J) and test group 2 (660 nm; power 20 mW; total energy 10 J); and untreated control group. All animals were taken surgical operation to make tibial defect on right crest of tibia. The test groups were treated every 48 hours with ILP. Bone volume and X-ray attenuation coefficient were measured on 0, 14th and 28th day with u-CT after treatment and were used to evaluate effect of LLLT. Results show that bone volume of test groups has been improved more than control group. X-ray attenuation coefficients of each groups have slightly different. The results suggest that LLLT combined with ILP may affect on early phase of bone regeneration and may be used in various musculoskeletal disease in deep tissue layer.

  16. Defining the Lower Limit of a "Critical Bone Defect" in Open Diaphyseal Tibial Fractures.

    PubMed

    Haines, Nikkole M; Lack, William D; Seymour, Rachel B; Bosse, Michael J

    2016-05-01

    To determine healing outcomes of open diaphyseal tibial shaft fractures treated with reamed intramedullary nailing (IMN) with a bone gap of 10-50 mm on ≥50% of the cortical circumference and to better define a "critical bone defect" based on healing outcome. Retrospective cohort study. Forty patients, age 18-65, with open diaphyseal tibial fractures with a bone gap of 10-50 mm on ≥50% of the circumference as measured on standard anteroposterior and lateral postoperative radiographs treated with IMN. IMN of an open diaphyseal tibial fracture with a bone gap. Level-1 trauma center. Healing outcomes, union or nonunion. Forty patients were analyzed. Twenty-one (52.5%) went on to nonunion and nineteen (47.5%) achieved union. Radiographic apparent bone gap (RABG) and infection were the only 2 covariates predicting nonunion outcome (P = 0.046 for infection). The RABG was determined by measuring the bone gap on each cortex and averaging over 4 cortices. Fractures achieving union had a RABG of 12 ± 1 mm versus 20 ± 2 mm in those going on to nonunion (P < 0.01). This remained significant when patients with infection were removed. Receiver operator characteristic analysis demonstrated that RABG was predictive of outcome (area under the curve of 0.79). A RABG of 25 mm was the statistically optimal threshold for prediction of healing outcome. Patients with open diaphyseal tibial fractures treated with IMN and a <25 mm RABG have a reasonable probability of achieving union without additional intervention, whereas those with larger gaps have a higher probability of nonunion. Research investigating interventions for RABGs should use a predictive threshold for defining a critical bone defect that is associated with greater than 50% risk of nonunion without supplementary treatment. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

  17. Area of the tibial insertion site of the anterior cruciate ligament as a predictor for graft size.

    PubMed

    Guenther, Daniel; Irarrázaval, Sebastian; Albers, Marcio; Vernacchia, Cara; Irrgang, James J; Musahl, Volker; Fu, Freddie H

    2017-05-01

    To determine the distribution of different sizes of the area of the tibial insertion site among the population and to evaluate whether preoperative MRI measurements correlate with intraoperative findings to enable preoperative planning of the required graft size to cover the tibial insertion site sufficiently. The hypothesis was that the area of the tibial insertion site varies among individuals and that there is good agreement between MRI and intraoperative measurements. Intraoperative measurements of the tibial insertion site were taken on 117 patients. Three measurements were taken in each plane building a grid to cover the tibial insertion site as closely as possible. The mean of the three measurements in each plane was used for determination of the area. Two orthopaedic surgeons, who were blinded to the intraoperative measurements, took magnetic resonance imaging (MRI) measurements of the area of the tibial insertion site at two different time points. The intraoperative measured mean area was 123.8 ± 21.5 mm 2 . The mean area was 132.8 ± 15.7 mm 2 (rater 1) and 136.7 ± 15.4 mm 2 (rater 2) when determined using MRI. The size of the area was approximately normally distributed. Inter-rater (0.89; 95 % CI 0.84, 0.92; p < 0.001) and intrarater reliability (rater 1: 0.97; 95 % CI 0.95, 0.98; p < 0.001; rater 2: 0.95; 95 % CI 0.92, 0.96; p < 0.001) demonstrated excellent test-retest reliability. There was good agreement between MRI and intraoperative measurement of tibial insertion site area (ICCs rater 1: 0.80; 95 % CI 0.71, 0.87; p < 0.001; rater 2: 0.87; 95 % CI 0.81, 0.91; p < 0.001). The tibial insertion site varies in size and shape. Preoperative determination of the area using MRI is repeatable and enables planning of graft choice and size to optimally cover the tibial insertion site. III.

  18. Ilizarov bone transport versus fibular graft for reconstruction of tibial bone defects in children.

    PubMed

    Abdelkhalek, Mostafa; El-Alfy, Barakat; Ali, Ayman M

    2016-11-01

    The aim of this study was to compare the results of treatment of segmental tibial defects in the pediatric age group using an Ilizarov external fixator versus a nonvascularized fibular bone graft. This study included 24 patients (age range from 5.5 to 15 years) with tibial bone defects: 13 patients were treated with bone transport (BT) and 11 patients were treated with a nonvascularized fibular graft (FG). The outcome parameters were bone results (union, deformity, infection, leg-length discrepancy) and functional results: external fixation index and external fixation time. In group A (BT), one patient developed refracture at the regenerate site, whereas, in group B (FG), after removal of the external fixator, one of the FGs developed a stress fracture. The external fixator time in group A was 10.7 months (range 8-14.5) versus 7.8 months (range 4-11.5 months) in group B (FG). In group A (BT), one patient had a limb-length discrepancy (LLD), whereas, in group B (FG), three patients had LLD. The functional and bone results of the Ilizarov BT technique were excellent in 23.1 and 30.8%, good in 38.5 and 46.2, fair in 30.8 and 15.4, and poor in 7.6 and 7.6%, respectively. The poor functional result was related to the poor bone result because of prolonged external fixator time resulting in significant pain, limited ankle motion, whereas the functional and bone results of fibular grafting were excellent in 9.1 and 18.2%, good in 63.6 and 45.5%, fair in 18.2 and 27.2%, and poor in 9.1 and 9.1%, respectively. Segmental tibial defects can be effectively treated with both methods. The FG method provides satisfactory results, with early removal of the external fixator. However, it had a limitation in patients with severe infection and those with LLD. Also, it requires a long duration of limb bracing until adequate hypertrophy of the graft. The Ilizarov method has the advantages of early weight bearing, treatment of postinfection bone defect in a one-stage surgery, and the

  19. Treatment of open tibial shaft fracture with soft tissue and bone defect caused by aircraft bomb--case report.

    PubMed

    Golubović, Zoran; Vidić, Goran; Trenkić, Srbobran; Vukasinović, Zoran; Lesić, Aleksandar; Stojiljković, Predrag; Stevanović, Goran; Golubović, Ivan; Visnjić, Aleksandar; Najman, Stevo

    2010-01-01

    Aircraft bombs can cause severe orthopaedic injuries. Tibia shaft fractures caused by aircraft bombs are mostly comminuted and followed by bone defects, which makes the healing process extremely difficult and prone to numerous complications. The goal of this paper is to present the method of treatment and the end results of treatment of a serious open tibial fracture with soft and bone tissue defects resulting from aircraft bomb shrapnel wounds. A 26-year-old patient presented with a tibial fracture as the result of a cluster bomb shrapnel wound. He was treated applying the method of external bone fixation done two days after wounding, as well as of early coverage of the lower leg soft tissue defects done on the tenth day after the external fixation of the fracture. The external fixator was removed after five months, whereas the treatment was continued by means of functional plaster cast for another two months. The final functional result was good. Radical wound debridement, external bone fixation of the fracture, and early reconstruction of any soft tissue and bone defects are the main elements of the treatment of serious fractures.

  20. Theoretical discrepancy between cage size and efficient tibial tuberosity advancement in dogs treated for cranial cruciate ligament rupture.

    PubMed

    Etchepareborde, S; Mills, J; Busoni, V; Brunel, L; Balligand, M

    2011-01-01

    To calculate the difference between the desired tibial tuberosity advancement (TTA) along the tibial plateau axis and the advancement truly achieved in that direction when cage size has been determined using the method of Montavon and colleagues. To measure the effect of this difference on the final patellar tendon-tibial plateau angle (PTA) in relation to the ideal 90°. Trigonometry was used to calculate the theoretical actual advancement of the tibial tuberosity in a direction parallel to the tibial plateau that would be achieved by the placement of a cage at the level of the tibial tuberosity in the osteotomy plane of the tibial crest. The same principle was used to calculate the size of the cage that would have been required to achieve the desired advancement. The effect of the difference between the desired advancement and the actual advancement achieved on the final PTA was calculated. For a given desired advancement, the greater the tibial plateau angle (TPA), the greater the difference between the desired advancement and the actual advancement achieved. The maximum discrepancy calculated was 5.8 mm for a 12 mm advancement in a case of extreme TPA (59°). When the TPA was less than 31°, the PTA was in the range of 90° to 95°. A discrepancy does exist between the desired tibial tuberosity advancement and the actual advancement in a direction parallel to the TPA, when the tibial tuberosity is not translated proximally. Although this has an influence on the final PTA, further studies are warranted to evaluate whether this is clinically significant.

  1. Induced membrane technique combined with two-stage internal fixation for the treatment of tibial osteomyelitis defects.

    PubMed

    Luo, Fei; Wang, Xiaohua; Wang, Shulin; Fu, Jingshu; Xie, Zhao

    2017-07-01

    The purpose of this study was to observe the effects of induced membrane technique combined with two-stage internal fixation in the treatment of tibial osteomyelitis defects. A retrospective analyses for 67 cases of tibialosteomyelitis defects were admitted to our department between September 2012 to February 2015, which were treated with induced membrane technique. At the first stage, implanted with a PMMA cement spacer in the defects after radical debridement and fixed with reconstructive locked plate. Bone grafting and exchanged the plate with intramedullary nail at the second stage. In current study, all patients were followed up for 18-35 months. Sixty-six patients achieved bone union with the average radiographic and clinical healing times of 5.55±2.19 and 7.45±1.69months, respectively. Seven patients required a second debridement before grafting, while four patients experienced a recurrence of infection or a relapse following second stage treatment. Twelve patients experienced either knee or ankle dysfunctions and 2 patients faced delayed wound healing. Donor site complications includes pain and infection were found in 7 and 3 patients, respectively with delayed stress fracture in 1 patient only. Induced membrane technique for the treatment of tibial osteomyelitis defects, seems a reliable method. The use of reconstructive locked plate as a temporary internal fixation at the first stage and exchanged with intramedullary nail at the second stage, potentially achieves good clinical efficacy. Care should be taken to restore the joint function especially in distal tibia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Does Treatment of the Tibia Matter in Bipolar Chondral Defects of the Knee? Clinical Outcomes with Greater Than 2 Years Follow-up.

    PubMed

    Hannon, Charles P; Weber, Alexander E; Gitelis, Matthew; Meyer, Maximillian A; Yanke, Adam B; Cole, Brian J

    2018-04-01

    To compare the osteochondral allograft (OCA) outcomes of bipolar defects with isolated femoral defects and to investigate the optimal treatment of bipolar defects by comparing femoral OCA with tibial debridement to femoral OCA and tibial microfracture. A series of patients with 2-year follow-up from March 2004 to September 2015 after femoral OCA for bipolar chondral defects was identified. Group 1 contained patients with tibial defects treated with debridement and group 2 contained patients with microfractured tibial defects. A third group (group 3) with isolated femoral defects treated with OCA was identified and matched by gender, body mass index (BMI), laterality, and OCA size to groups 1 and 2. Patient-specific, defect-specific, intraoperative, and postoperative data including patient-reported outcomes were collected on all patients. The study groups were compared using analyses of variance, paired sample t tests, and χ-square analyses. Thirty-six patients who had femoral OCA for bipolar lesions were identified with 20 patients in group 1 and 16 patients in group 2. Group 3 had 20 patients. There were no differences between the 3 groups in terms of gender (P = .616), BMI (P = .271), number of previous surgeries (P = .451), femoral or tibial defect size (P = .296), and OCA size (P = .981). Preoperative to postoperative patient-reported clinical outcomes (PROs) revealed statistical and clinically meaningful improvement in all 3 groups, but did not differ between groups. Patient-specific and defect-specific factors did not correlate with PROs. The graft survivorship for group 1 was 85% at 4.5 years, 100% for group 2 at 2.5 years, and 95% for group 3 at 3.8 years. Regardless of tibial treatment, patients with bipolar defects treated with femoral OCA have clinically meaningful improvements in PROs and excellent graft survivorship comparable to isolated femoral OCAs at more than 2 years. Level III, case-control study. Copyright © 2017 Arthroscopy

  3. 3D printed alendronate-releasing poly(caprolactone) porous scaffolds enhance osteogenic differentiation and bone formation in rat tibial defects.

    PubMed

    Kim, Sung Eun; Yun, Young-Pil; Shim, Kyu-Sik; Kim, Hak-Jun; Park, Kyeongsoon; Song, Hae-Ryong

    2016-09-29

    The aim of this study was to evaluate the in vitro osteogenic effects and in vivo new bone formation of three-dimensional (3D) printed alendronate (Aln)-releasing poly(caprolactone) (PCL) (Aln/PCL) scaffolds in rat tibial defect models. 3D printed Aln/PCL scaffolds were fabricated via layer-by-layer deposition. The fabricated Aln/PCL scaffolds had high porosity and an interconnected pore structure and showed sustained Aln release. In vitro studies showed that MG-63 cells seeded on the Aln/PCL scaffolds displayed increased alkaline phosphatase (ALP) activity and calcium content in a dose-dependent manner when compared with cell cultures in PCL scaffolds. In addition, in vivo animal studies and histologic evaluation showed that Aln/PCL scaffolds implanted in a rat tibial defect model markedly increased new bone formation and mineralized bone tissues in a dose-dependent manner compared to PCL-only scaffolds. Our results show that 3D printed Aln/PCL scaffolds are promising templates for bone tissue engineering applications.

  4. Tibial bone fractures occurring after medioproximal tibial bone grafts for oral and maxillofacial reconstruction.

    PubMed

    Kim, Il-Kyu; Cho, Hyun-Young; Pae, Sang-Pill; Jung, Bum-Sang; Cho, Hyun-Woo; Seo, Ji-Hoon

    2013-12-01

    Oral and maxillofacial defects often require bone grafts to restore missing tissues. Well-recognized donor sites include the anterior and posterior iliac crest, rib, and intercalvarial diploic bone. The proximal tibia has also been explored as an alternative donor site. The use of the tibia for bone graft has many benefits, such as procedural ease, adequate volume of cancellous and cortical bone, and minimal complications. Although patients rarely complain of pain, swelling, discomfort, or dysfunction, such as gait disturbance, both patients and surgeons should pay close attention to such after effects due to the possibility of tibial fracture. The purpose of this study is to analyze tibial fractures that occurring after osteotomy for a medioproximal tibial graft. An analysis was intended for patients who underwent medioproximal tibial graft between March 2004 and December 2011 in Inha University Hospital. A total of 105 subjects, 30 females and 75 males, ranged in age from 17 to 78 years. We investigated the age, weight, circumstance, and graft timing in relation to tibial fracture. Tibial fractures occurred in four of 105 patients. There were no significant differences in graft region, shape, or scale between the fractured and non-fractured patients. Patients who undergo tibial grafts must be careful of excessive external force after the operation.

  5. Posterior tibial slope and femoral sizing affect posterior cruciate ligament tension in posterior cruciate-retaining total knee arthroplasty.

    PubMed

    Kuriyama, Shinichi; Ishikawa, Masahiro; Nakamura, Shinichiro; Furu, Moritoshi; Ito, Hiromu; Matsuda, Shuichi

    2015-08-01

    During cruciate-retaining total knee arthroplasty, surgeons sometimes encounter increased tension of the posterior cruciate ligament. This study investigated the effects of femoral size, posterior tibial slope, and rotational alignment of the femoral and tibial components on forces at the posterior cruciate ligament in cruciate-retaining total knee arthroplasty using a musculoskeletal computer simulation. Forces at the posterior cruciate ligament were assessed with the standard femoral component, as well as with 2-mm upsizing and 2-mm downsizing in the anterior-posterior dimension. These forces were also determined with posterior tibial slope angles of 5°, 7°, and 9°, and lastly, were measured in 5° increments when the femoral (tibial) components were positioned from 5° (15°) of internal rotation to 5° (15°) of external rotation. Forces at the posterior cruciate ligament increased by up to 718N with the standard procedure during squatting. The 2-mm downsizing of the femoral component decreased the force at the posterior cruciate ligament by up to 47%. The 2° increment in posterior tibial slope decreased the force at the posterior cruciate ligament by up to 41%. In addition, posterior cruciate ligament tension increased by 11% during internal rotation of the femoral component, and increased by 18% during external rotation of the tibial component. These findings suggest that accurate sizing and bone preparation are very important to maintain posterior cruciate ligament forces in cruciate-retaining total knee arthroplasty. Care should also be taken regarding malrotation of the femoral and tibial components because this increases posterior cruciate ligament tension. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. The proximally based long peroneal muscle turnover flap: A novel salvage flap for small to medium-sized defects of the knee.

    PubMed

    Wagner, Till; Hupkens, Pieter; Slater, Nicholas J; Ulrich, Dietmar J O

    2016-04-01

    Coverage of soft-tissue defects of the knee due to multiple operations, trauma, and infection remains a surgical challenge. Often, these defects are repaired using free tissue transfer. The aim of this study was to find an easy and reliable local method of repair for small to medium-sized defects. The authors describe a new surgical option for tissue coverage using a proximally based long peroneal muscle turnover flap (LPTF) with split-thickness skin graft. Proximally based LPTFs were harvested and transposed into same-size created defects in five cadavers. After optimizing this technique, it was clinically used in two patients with defects secondary to total knee replacement revisions. Average cadaver flap size was 4.7 × 15.8 cm allowing reach of all knee joint areas and was based consistently on a sufficient (2-mm-diameter average) proximal arterial branch of the anterior tibial artery. Donor sites were closed without tension. Subsequent application of the flap on two patients resulted in good functional outcome. The proximally based LPTF is a new option available in the reconstruction of knee defects and should be added to the reconstructive surgeon's armamentarium of pedicled flaps, providing short operating time and promising clinical outcome. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  7. Effect of Hydroxyapatite on Bone Integration in a Rabbit Tibial Defect Model

    PubMed Central

    Sohn, Sung-Keun; Kim, Kyung-Taek; Kim, Chul-Hong; Ahn, Hee-Bae; Rho, Mee-Sook; Jeong, Min-Ho; Sun, Sang-Kyu

    2010-01-01

    Background The aim of the present study was to prepare hydroxyapatite (HA) and then characterize its effect on bone integration in a rabbit tibial defect model. The bone formation with different designs of HA was compared and the bony integration of several graft materials was investigated qualitatively by radiologic and histologic study. Methods Ten rabbits were included in this study; two holes were drilled bilaterally across the near cortex and the four holes in each rabbit were divided into four treatment groups (HAP, hydroxyapatite powder; HAC, hydroxyapatite cylinder; HA/TCP, hydroxyapatite/tri-calcium phosphate cylinder, and titanium cylinder). The volume of bone ingrowth and the change of bone mineral density were statistically calculated by computed tomography five times for each treatment group at 0, 2, 4, 6, and 8 weeks after grafting. Histologic analysis was performed at 8 weeks after grafting. Results The HAP group showed the most pronounced effect on the bone ingrowth surface area, which seen at 4, 6, and 8 weeks after graft (p < 0.05). On comparing the change of bone mineral density the bone ingrowth surface area among the 4 groups, there were no statistically significant differences among the groups found for any period (p > 0.05). On histological examination, the HAP group revealed well-recovered cortical bone, but the bone was irregularly thickened and haphazardly admixed with powder. The HAC group showed similar histological features to those of the HA/TCP group; the cortical surface of the newly developed bone was smooth and the bone matrix on the surface of the cylinder was regularly arranged. Conclusions We concluded that both the hydroxyapatite powder and cylinder models investigated in our study may be suitable as a bone substitute in the rabbit tibial defect model, but their characteristic properties are quite different. In contrast to hydroxyapatite powder, which showed better results for the bone ingrowth surface, the hydroxyapatite

  8. Anthropometric measurements of tibial plateau and correlation with the current tibial implants.

    PubMed

    Erkocak, Omer Faruk; Kucukdurmaz, Fatih; Sayar, Safak; Erdil, Mehmet Emin; Ceylan, Hasan Huseyin; Tuncay, Ibrahim

    2016-09-01

    The aim of the study was to make an anthropometric analysis at the resected surfaces of the proximal tibia in the Turkish population and to compare the data with the dimensions of tibial components in current use. We hypothesized that tibial components currently available on the market do not fulfil the requirements of this population and a new tibial component design may be required, especially for female patients with small stature. Anthropometric data from the proximal tibia of 226 knees in 226 Turkish subjects were measured using magnetic resonance imaging. We measured the mediolateral, middle anteroposterior, medial and lateral anteroposterior dimensions and the aspect ratio of the resected proximal tibial surface. All morphological data were compared with the dimensions of five contemporary tibial implants, including asymmetric and symmetric design types. The dimensions of the tibial plateau of Turkish knees demonstrated significant differences according to gender (P < 0.05). Among the different tibial implants reviewed, neither asymmetric nor symmetric designs exhibited a perfect conformity to proximal tibial morphology in size and shape. The vast majority of tibial implants involved in this study tend to overhang anteroposteriorly, and a statistically significant number of women (21 %, P < 0.05) had tibial anteroposterior diameters smaller than the smallest available tibial component. Tibial components designed according to anthropometric measurements of Western populations do not perfectly meet the requirements of Turkish population. These data could provide the basis for designing the optimal and smaller tibial component for this population, especially for women, is required for best fit. II.

  9. Relationship between tibial spine size and the occurrence of osteochondritis dissecans: an argument in favour of the impingement theory.

    PubMed

    Cavaignac, Etienne; Perroncel, Geoffroy; Thépaut, Mathias; Vial, Julie; Accadbled, Franck; De Gauzy, Jérôme Sales

    2017-08-01

    Pathophysiology of osteochondritis dissecans (OCD) of the medial femoral condyle remains uncertain. Specifically, the relationship between the size of the anterior tibial spine (ATS) and the presence of OCD has not been explored. The purpose of this study was to evaluate the relationship between ATS size and the occurrence of OCD. Seventy-nine children between 8 and 17 years of age were included in two groups: OCD (n = 37) and control (n = 42). The groups were matched in terms of age, gender, BMI and weight. Two independent observers performed an MRI analysis of the size of the tibial spine and intercondylar notch relative to the size of the respective epiphyses. For this study, the "S ratio" was calculated by dividing the height of the tibial spine by the height of the tibial epiphysis. The "N ratio" was calculated by dividing the height of the notch by the height of the femoral epiphysis. These two ratios for both groups were compared using Student's t test. The mean value of the S ratio in the OCD group was 0.39 ± 0.06; the mean value of the S ratio in the control group was 0.32 ± 0.03 (P = 0.004). The mean value of the N ratio in the OCD group was 0.70 ± 0.08; the mean value of the N ratio in the control group was 0.70 ± 0.07 (n.s.). This study's findings confirm our hypothesis that patients with OCD have a more prominent tibial spine than in patients without OCD. IV.

  10. The use of tibial tuberosity-trochlear groove indices based on joint size in lower limb evaluation.

    PubMed

    Ferlic, Peter Wilhelm; Runer, Armin; Dirisamer, Florian; Balcarek, Peter; Giesinger, Johannes; Biedermann, Rainer; Liebensteiner, Michael Christian

    2018-05-01

    The correlation between tibial tuberosity-trochlear groove distance (TT-TG) and joint size, taking into account several different parameters of knee joint size as well as lower limb dimensions, is evaluated in order to assess whether TT-TG indices should be used in instead of absolute TT-TG values. This study comprised a retrospective analysis of knee CT scans, including 36 cases with patellofemoral instability (PFI) and 30 controls. Besides TT-TG, five measures of knee joint size were evaluated in axial CT slices: medio-lateral femur width, antero-posterior lateral condylar height, medio-lateral width of the tibia, width of the patella and the proximal-distal joint size (TT-TE). Furthermore, the length of the femur, the tibia and the total leg length were measured in the CT scanogram. Correlation analysis of TT-TG and the other parameters was done by calculating the Spearman correlation coefficient. In the PFI group lateral condylar height (r = 0.370), tibia width (r = 0.406) and patella width (r = 0.366) showed significant moderate correlations (p < 0.03) with TT-TG. Furthermore, we found a significant correlation between TT-TG and tibia length (r = 0.371) and total leg length (r = 381). The control group showed no significant correlation between TT-TG and knee joint size or between TT-TG and measures of lower limb length. Tibial tuberosity-trochlear groove distance correlates with several parameters of knee joint size and leg length in patients with patellofemoral instability. Application of indices determining TT-TG as a ratio of joint size could be helpful in establishing the indication for medial transfer of the tibial tuberosity in patients with PFI. Level III.

  11. The indications and donor-site morbidity of tibial cortical strut autografts in the management of defects in long bones.

    PubMed

    Lauthe, O; Soubeyrand, M; Babinet, A; Dumaine, V; Anract, P; Biau, D J

    2018-05-01

    Aims The primary aim of this study was to determine the morbidity of a tibial strut autograft and characterize the rate of bony union following its use. Patients and Methods We retrospectively assessed a series of 104 patients from a single centre who were treated with a tibial strut autograft of > 5 cm in length. A total of 30 had a segmental reconstruction with continuity of bone, 27 had a segmental reconstruction without continuity of bone, 29 had an arthrodesis and 18 had a nonunion. Donor-site morbidity was defined as any event that required a modification of the postoperative management. Union was assessed clinically and radiologically at a median of 36 months (IQR, 14 to 74). Results Donor-site morbidity occurred in four patients (4%; 95% confidence interval (CI) 1 to 10). One patient had a stress fracture of the tibia, which healed with a varus deformity, requiring an osteotomy. Two patients required evacuation of a haematoma and one developed anterior compartment syndrome which required fasciotomies. The cumulative probability of union was 90% (95% CI 80 to 96) at five years. The type of reconstruction (p = 0.018), continuity of bone (p = 0.006) and length of tibial graft (p = 0.037) were associated with the time to union. Conclusion The tibial strut autograft has a low risk of morbidity and provides adequate bone stock for treating various defects of long bones. Cite this article: Bone Joint J 2018;100-B:667-74.

  12. Treatment of open tibial fracture with bone defect caused by high velocity missiles: a case report.

    PubMed

    Golubović, Zoran; Vukajinović, Zoran; Stojiljković, Predrag; Golubović, Ivan; Visnjić, Aleksandar; Radovanović, Zoran; Najman, Stevo

    2013-01-01

    Tibia fracture caused by high velocity missiles is mostly comminuted and followed by bone defect which makes their healing process extremely difficult and prone to numerous complications. A 34-year-old male was wounded at close range by a semi-automatic gun missile. He was wounded in the distal area of the left tibia and suffered a massive defect of the bone and soft tissue. After the primary treatment of the wound, the fracture was stabilized with an external fixator type Mitkovic, with convergent orientation of the pins. The wound in the medial region of the tibia was closed with the secondary stitch, whereas the wound in the lateral area was closed with the skin transplant after Thiersch. Due to massive bone defect in the area of the rifle-missile wound six months after injury, a medical team placed a reconstructive external skeletal fixator type Mitkovic and performed corticotomy in the proximal metaphyseal area of the tibia. By the method of bone transport (distractive osteogenesis), the bone defect of the tibia was replaced. After the fracture healing seven months from the secondary surgery, the fixator was removed and the patient was referred to physical therapy. Surgical treatment of wounds, external fixation, performing necessary debridement, adequate antibiotic treatment and soft and bone tissue reconstruction are essential in achieving good results in patients with the open tibial fracture with bone defect caused by high velocity missiles. Reconstruction of bone defect can be successfully treated by reconstructive external fixator Mitkovic.

  13. Anatomic tibial component design can increase tibial coverage and rotational alignment accuracy: a comparison of six contemporary designs.

    PubMed

    Dai, Yifei; Scuderi, Giles R; Bischoff, Jeffrey E; Bertin, Kim; Tarabichi, Samih; Rajgopal, Ashok

    2014-12-01

    The aim of this study was to comprehensively evaluate contemporary tibial component designs against global tibial anatomy. We hypothesized that anatomically designed tibial components offer increased morphological fit to the resected proximal tibia with increased alignment accuracy compared to symmetric and asymmetric designs. Using a multi-ethnic bone dataset, six contemporary tibial component designs were investigated, including anatomic, asymmetric, and symmetric design types. Investigations included (1) measurement of component conformity to the resected tibia using a comprehensive set of size and shape metrics; (2) assessment of component coverage on the resected tibia while ensuring clinically acceptable levels of rotation and overhang; and (3) evaluation of the incidence and severity of component downsizing due to adherence to rotational alignment and overhang requirements, and the associated compromise in tibial coverage. Differences in coverage were statistically compared across designs and ethnicities, as well as between placements with or without enforcement of proper rotational alignment. Compared to non-anatomic designs investigated, the anatomic design exhibited better conformity to resected tibial morphology in size and shape, higher tibial coverage (92% compared to 85-87%), more cortical support (posteromedial region), lower incidence of downsizing (3% compared to 39-60%), and less compromise of tibial coverage (0.5% compared to 4-6%) when enforcing proper rotational alignment. The anatomic design demonstrated meaningful increase in tibial coverage with accurate rotational alignment compared to symmetric and asymmetric designs, suggesting its potential for less intra-operative compromises and improved performance. III.

  14. Mean Glenoid Defect Size and Location Associated With Anterior Shoulder Instability

    PubMed Central

    Gottschalk, Lionel J.; Bois, Aaron J.; Shelby, Marcus A.; Miniaci, Anthony; Jones, Morgan H.

    2017-01-01

    Background: There is a strong correlation between glenoid defect size and recurrent anterior shoulder instability. A better understanding of glenoid defects could lead to improved treatments and outcomes. Purpose: To (1) determine the rate of reporting numeric measurements for glenoid defect size, (2) determine the consistency of glenoid defect size and location reported within the literature, (3) define the typical size and location of glenoid defects, and (4) determine whether a correlation exists between defect size and treatment outcome. Study Design: Systematic review; Level of evidence, 4. Methods: PubMed, Ovid, and Cochrane databases were searched for clinical studies measuring glenoid defect size or location. We excluded studies with defect size requirements or pathology other than anterior instability and studies that included patients with known prior surgery. Our search produced 83 studies; 38 studies provided numeric measurements for glenoid defect size and 2 for defect location. Results: From 1981 to 2000, a total of 5.6% (1 of 18) of the studies reported numeric measurements for glenoid defect size; from 2001 to 2014, the rate of reporting glenoid defects increased to 58.7% (37 of 63). Fourteen studies (n = 1363 shoulders) reported defect size ranges for percentage loss of glenoid width, and 9 studies (n = 570 shoulders) reported defect size ranges for percentage loss of glenoid surface area. According to 2 studies, the mean glenoid defect orientation was pointing toward the 3:01 and 3:20 positions on the glenoid clock face. Conclusion: Since 2001, the rate of reporting numeric measurements for glenoid defect size was only 58.7%. Among studies reporting the percentage loss of glenoid width, 23.6% of shoulders had a defect between 10% and 25%, and among studies reporting the percentage loss of glenoid surface area, 44.7% of shoulders had a defect between 5% and 20%. There is significant variability in the way glenoid bone loss is measured, calculated

  15. Measurement of anterior tibial muscle size using real-time ultrasound imaging.

    PubMed

    Martinson, H; Stokes, M J

    1991-01-01

    Cross-sectional images of the anterior tibial muscle group were obtained using real-time ultrasound scanning in 17 normal women. From photographs taken of the images, the cross-sectional area (CSA) and two linear measurements of muscle cross-section were determined. A measurement of the shortest distance of the muscle depth was termed DS, and a measurement of the longest distance through the muscle group was termed DL. Both linear dimensions showed a positive correlation with CSA and the best correlations were obtained when the dimensions were squared or combined (DS x DL). The correlation values were: CSA vs DS2, r = 0.9; CSA vs DL2, r = 0.75 and CSA vs DS x DL, r = 0.88. An approximate value for CSA could be calculated from DS2 by the equation 2 x DS2 + 1. A shape ratio, obtained by dividing DL by DS, was consistent within the group [mean 2.1 (SD 0.2)] and characterised the muscle geometrically. The CSA of repeated scans was assessed for repeatability between-days and between-scans by analysis of variance and the coefficient of variation (CV) calculated. Areas were repeatable between-days (CV 6.5%) and between-scans (CV 3.6%). Linear dimensions of the anterior tibial muscle group reflected CSA and their potential for assessing changes in muscle size with atrophy and hypertrophy have yet to be established.

  16. Defect formation energy in pyrochlore: the effect of crystal size

    NASA Astrophysics Data System (ADS)

    Wang, Jianwei; Ewing, Rodney C.; Becker, Udo

    2014-09-01

    Defect formation energies of point defects of two pyrochlores Gd2Ti2O7 and Gd2Zr2O7 as a function of crystal size were calculated. Density functional theory with plane-wave basis sets and the projector-augmented wave method were used in the calculations. The results show that the defect formation energies of the two pyrochlores diverge as the size decreases to the nanometer range. For Gd2Ti2O7 pyrochlore, the defect formation energy is higher at nanometers with respect to that of the bulk, while it is lower for Gd2Zr2O7. The lowest defect formation energy for Gd2Zr2O7 is found at 15-20 Å. The different behaviors of the defect formation energies as a function of crystal size are caused by different structural adjustments around the defects as the size decreases. For both pyrochlore compositions at large sizes, the defect structures are similar to those of the bulk. As the size decreases, for Gd2Ti2O7, additional structure distortions appear at the surfaces, which cause the defect formation energy to increase. For Gd2Zr2O7, additional oxygen Frenkel pair defects are introduced, which reduce the defect formation energy. As the size further decreases, increased structure distortions occur at the surfaces, which cause the defect formation energy to increase. Based on a hypothesis that correlates the energetics of defect formation and radiation response for complex oxides, the calculated results suggest that at nanometer range Gd2Ti2O7 pyrochlore is expected to have a lower radiation tolerance, and those of Gd2Zr2O7 pyrochlore to have a higher radiation tolerance. The highest radiation tolerance for Gd2Zr2O7 pyrochlore is expected to be found at ˜2 nanometers.

  17. Adaptations in tibial cortical thickness and total volumetric bone density in postmenopausal South Asian women with small bone size.

    PubMed

    Darling, Andrea L; Hakim, Ohood A; Horton, Khim; Gibbs, Michelle A; Cui, Liang; Berry, Jacqueline L; Lanham-New, Susan A; Hart, Kathryn H

    2013-07-01

    There is some evidence that South Asian women may have an increased risk of osteoporosis compared with Caucasian women, although whether South Asians are at increased risk of fracture is not clear. It is unknown whether older South Asian women differ from Caucasian women in bone geometry. This is the first study, to the authors' knowledge, to use peripheral Quantitative Computed Tomography (pQCT) to measure radial and tibial bone geometry in postmenopausal South Asian women. In comparison to Caucasian women, Asian women had smaller bone size at the 4% (-18% p<0.001) and 66% radius (-15% p=0.04) as well as increased total density at the 4% (+13% p=0.01) radius. For the tibia, they had a smaller bone size at the 4% (-16% p=0.005) and 14% (-38% p=0.002) sites. Also, Asians had increased cortical thickness (-17% p=0.04) at the 38% tibia, (in proportion to bone size (-30% p=0.003)). Furthermore, at the 4% and 14% tibia there were increased total densities (+12% to +29% p<0.01) and at the 14% tibia there was increased cortical density (+5% p=0.005) in Asians. These differences at the 14% and 38% (but not 4%) remained statistically significant after adjustment for Body Mass Index (BMI). These adaptations are similar to those seen previously in Chinese women. Asian women had reduced strength at the radius and tibia, evidenced by the 20-40% reduction in both polar Strength Strain Index (SSIp) and fracture load (under bending). Overall, the smaller bone size in South Asians is likely to be detrimental to bone strength, despite some adaptations in tibial cortical thickness and tibial and radial density which may partially compensate for this. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Management of tibial non-unions according to a novel treatment algorithm.

    PubMed

    Ferreira, Nando; Marais, Leonard Charles

    2015-12-01

    Tibial non-unions represent a spectrum of conditions that are challenging to treat. The optimal management remains unclear despite the frequency with which these diagnoses are encountered. The aim of this study was to determine the outcome of tibial non-unions managed according to a novel tibial non-union treatment algorithm. One hundred and eighteen consecutive patients with 122 uninfected tibial non-unions were treated according to our proposed tibial non-union treatment algorithm. All patients were followed-up clinically and radiologically for a minimum of six months after external fixator removal. Four patients were excluded because they did not complete the intended treatment process. The final study population consisted of 94 men and 24 women with a mean age of 34 years. Sixty-seven non-unions were stiff hypertrophic, 32 mobile atrophic, 16 mobile oligotrophic and one true pseudoarthrosis. Six non-unions were classified as type B1 defect non-unions. Bony union was achieved after the initial surgery in 113/122 (92.6%) tibias. Nine patients had failure of treatment. Seven persistent non-unions were successfully retreated according to the tibial non-union treatment algorithm. This resulted in final bony union in 120/122 (98.3%) tibias. The proposed tibial non-union treatment algorithm appears to produce high union rates across a diverse group of tibial non-unions. Tibial non-unions however, remain difficult to treat and should be referred to specialist units where advanced reconstructive techniques are practiced on a regular basis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Multiple Osteochondral Allograft Transplantation with Concomitant Tibial Tubercle Osteotomy for Multifocal Chondral Disease of the Knee.

    PubMed

    Cotter, Eric J; Waterman, Brian R; Kelly, Mick P; Wang, Kevin C; Frank, Rachel M; Cole, Brian J

    2017-08-01

    Symptomatic patellofemoral chondral lesions are a challenging clinical entity, as these defects may result from persistent lateral patellar maltracking or repetitive microtrauma. Anteromedializing tibial tubercle osteotomy has been shown to be an effective strategy for primary and adjunctive treatment of focal or diffuse patellofemoral disease to improve the biomechanical loading environment. Similarly, osteochondral allograft transplantation has proven efficacy in physiologically young, high-demand patients with condylar or patellofemoral lesions, particularly without early arthritic progression. The authors present the surgical management of a young athlete with symptomatic tricompartmental focal chondral defects with fresh osteochondral allograft transplantation and anteromedializing tibial tubercle osteotomy.

  20. Outcomes assessment in the SPRINT multicenter tibial fracture trial: Adjudication committee size has trivial effect on trial results.

    PubMed

    Simunovic, Nicole; Walter, Stephen; Devereaux, P J; Sprague, Sheila; Guyatt, Gordon H; Schemitsch, Emil; Tornetta, Paul; Sanders, David; Swiontkowski, Marc; Bhandari, Mohit

    2011-09-01

    To evaluate how the size of an outcome adjudication committee, and the potential for dominance among its members, potentially impacts a trial's results. We conducted a retrospective analysis of data from the six-member adjudication committee in the Study to Prospectively Evaluate Reamed Intramedullary Nails in Patients with Tibial Fractures (SPRINT) Trial. We modeled the adjudication process, predicted the results and costs if smaller committees had been used, and tested for the presence of a dominant adjudicator. Use of smaller committee sizes (one to five members) would have had little impact on the final study results, although one analysis suggested that the benefit in reduction of reoperations with reamed nails in closed tibial fractures would have lost significance if committee sizes of three or less were used. We identified a significant difference between adjudicators in the number of times their original minority decisions became the final consensus decision (χ(2)=9.67, P=0.046), suggesting that dominant adjudicators were present. However, their impact on the final study results was trivial. Reducing the number of adjudicators from six to four would have led to little change in the final SPRINT study results irrespective of the significance of the original trial results, demonstrating the potential for savings in trial resources. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. The effect of defect cluster size and interpolation on radiographic image quality

    NASA Astrophysics Data System (ADS)

    Töpfer, Karin; Yip, Kwok L.

    2011-03-01

    For digital X-ray detectors, the need to control factory yield and cost invariably leads to the presence of some defective pixels. Recently, a standard procedure was developed to identify such pixels for industrial applications. However, no quality standards exist in medical or industrial imaging regarding the maximum allowable number and size of detector defects. While the answer may be application specific, the minimum requirement for any defect specification is that the diagnostic quality of the images be maintained. A more stringent criterion is to keep any changes in the images due to defects below the visual threshold. Two highly sensitive image simulation and evaluation methods were employed to specify the fraction of allowable defects as a function of defect cluster size in general radiography. First, the most critical situation of the defect being located in the center of the disease feature was explored using image simulation tools and a previously verified human observer model, incorporating a channelized Hotelling observer. Detectability index d' was obtained as a function of defect cluster size for three different disease features on clinical lung and extremity backgrounds. Second, four concentrations of defects of four different sizes were added to clinical images with subtle disease features and then interpolated. Twenty observers evaluated the images against the original on a single display using a 2-AFC method, which was highly sensitive to small changes in image detail. Based on a 50% just-noticeable difference, the fraction of allowed defects was specified vs. cluster size.

  2. External fixation of tibial pilon fractures and fracture healing.

    PubMed

    Ristiniemi, Jukka

    2007-06-01

    Distal tibial fractures are rare and difficult to treat because the bones are subcutaneous. External fixation is commonly used, but the method often results in delayed union. The aim of the present study was to find out the factors that affect fracture union in tibial pilon fractures. For this purpose, prospective data collection of tibial pilon fractures was carried out in 1998-2004, resulting in 159 fractures, of which 83 were treated with external fixation. Additionally, 23 open tibial fractures with significant > 3 cm bone defect that were treated with a staged method in 2000-2004 were retrospectively evaluated. The specific questions to be answered were: What are the risk factors for delayed union associated with two-ring hybrid external fixation? Does human recombinant BMP-7 accelerate healing? What is the role of temporary ankle-spanning external fixation? What is the healing potential of distal tibial bone loss treated with a staged method using antibiotic beads and subsequent autogenous cancellous grafting compared to other locations of the tibia? The following risk factors for delayed healing after external fixation were identified: post-reduction fracture gap of >3 mm and fixation of the associated fibula fracture. Fracture displacement could be better controlled with initial temporary external fixation than with early definitive fixation, but it had no significant effect on healing time, functional outcome or complication rate. Osteoinduction with rhBMP-7 was found to accelerate fracture healing and to shorten the sick leave. A staged method using antibiotic beads and subsequent autogenous cancellous grafting proved to be effective in the treatment of tibial bone loss. Healing potential of the bone loss in distal tibia was at least equally good as in other locations of the tibia.

  3. Kinematically aligned total knee arthroplasty limits high tibial forces, differences in tibial forces between compartments, and abnormal tibial contact kinematics during passive flexion.

    PubMed

    Roth, Joshua D; Howell, Stephen M; Hull, Maury L

    2018-06-01

    Following total knee arthroplasty (TKA), high tibial forces, large differences in tibial forces between the medial and lateral compartments, and anterior translation of the contact locations of the femoral component on the tibial component during passive flexion indicate abnormal knee function. Because the goal of kinematically aligned TKA is to restore native knee function without soft tissue release, the objectives were to determine how well kinematically aligned TKA limits high tibial forces, differences in tibial forces between compartments, and anterior translation of the contact locations of the femoral component on the tibial component during passive flexion. Using cruciate retaining components, kinematically aligned TKA was performed on thirteen human cadaveric knee specimens with use of manual instruments without soft tissue release. The tibial forces and tibial contact locations were measured in both the medial and lateral compartments from 0° to 120° of passive flexion using a custom tibial force sensor. The average total tibial force (i.e. sum of medial + lateral) ranged from 5 to 116 N. The only significant average differences in tibial force between compartments occurred at 0° of flexion (29 N, p = 0.0008). The contact locations in both compartments translated posteriorly in all thirteen kinematically aligned TKAs by an average of 14 mm (p < 0.0001) and 18 mm (p < 0.0001) in the medial and lateral compartments, respectively, from 0° to 120° of flexion. After kinematically aligned TKA, average total tibial forces due to the soft tissue restraints were limited to 116 N, average differences in tibial forces between compartments were limited to 29 N, and a net posterior translation of the tibial contact locations was observed in all kinematically aligned TKAs during passive flexion from 0° to 120°, which are similar to what has been measured previously in native knees. While confirmation in vivo is warranted, these findings give

  4. Management of Distal Tibial Metaphyseal Bone Defects With an Intramedullary Nitinol Scaffold: A Novel Technique.

    PubMed

    Ford, Samuel E; Ellington, J Kent

    2017-08-01

    Difficult problems that are faced when reconstructing severe pilon fractures include filling metaphyseal defects and supporting an impacted, multifragmented articular surface. Supplements to plate fixation currently available in a surgeon's armamentarium include cancellous bone autograft, structural bone allograft, demineralized bone matrix, and calcium-based cements. Cancellous autograft possesses limited inherent mechanical stability and is associated with graft site morbidity. Structural allografts incorporate inconsistently and are plagued by late resorption. Demineralized bone matrix also lacks inherent structural stability. Calcium phosphate cements are not rigidly fixed to bone unless fixation is applied from cortical bone or through a plate, which must be taken into consideration when planning fixation. The Conventus DRS (Conventus Orthopaedics, Maple Grove, MN) implant is an expandable nitinol scaffold that takes advantage of the elasticity and shape memory of nitinol alloy. Once deployed and locked, it serves as a stable intramedullary base for fragment-specific periarticular fracture fixation, even in the face of metaphyseal bone loss. Two cases of successful implant use are presented. In both cases, the implant is used to fill a metaphyseal void and provide stable articular support to the distal tibial plafond. Therapeutic Level V: Case Report, Expert Opinion.

  5. Establishment of a preclinical ovine model for tibial segmental bone defect repair by applying bone tissue engineering strategies.

    PubMed

    Reichert, Johannes C; Epari, Devakara R; Wullschleger, Martin E; Saifzadeh, Siamak; Steck, Roland; Lienau, Jasmin; Sommerville, Scott; Dickinson, Ian C; Schütz, Michael A; Duda, Georg N; Hutmacher, Dietmar W

    2010-02-01

    Currently, well-established clinical therapeutic approaches for bone reconstruction are restricted to the transplantation of autografts and allografts, and the implantation of metal devices or ceramic-based implants to assist bone regeneration. Bone grafts possess osteoconductive and osteoinductive properties; however, they are limited in access and availability and associated with donor-site morbidity, hemorrhage, risk of infection, insufficient transplant integration, graft devitalization, and subsequent resorption resulting in decreased mechanical stability. As a result, recent research focuses on the development of alternative therapeutic concepts. The field of tissue engineering has emerged as an important approach to bone regeneration. However, bench-to-bedside translations are still infrequent as the process toward approval by regulatory bodies is protracted and costly, requiring both comprehensive in vitro and in vivo studies. The subsequent gap between research and clinical translation, hence, commercialization, is referred to as the "Valley of Death" and describes a large number of projects and/or ventures that are ceased due to a lack of funding during the transition from product/technology development to regulatory approval and subsequently commercialization. One of the greatest difficulties in bridging the Valley of Death is to develop good manufacturing processes and scalable designs and to apply these in preclinical studies. In this article, we describe part of the rationale and road map of how our multidisciplinary research team has approached the first steps to translate orthopedic bone engineering from bench to bedside by establishing a preclinical ovine critical-sized tibial segmental bone defect model, and we discuss our preliminary data relating to this decisive step.

  6. Medial Tibial Stress Shielding: A Limitation of Cobalt Chromium Tibial Baseplates.

    PubMed

    Martin, J Ryan; Watts, Chad D; Levy, Daniel L; Kim, Raymond H

    2017-02-01

    Stress shielding is a well-recognized complication associated with total knee arthroplasty. However, this phenomenon has not been thoroughly described. Specifically, no study to our knowledge has evaluated the radiographic impact of utilizing various tibial component compositions on tibial stress shielding. We retrospectively reviewed 3 cohorts of 50 patients that had a preoperative varus deformity and were implanted with a titanium, cobalt chromium (CoCr), or an all polyethylene tibial implant. A radiographic comparative analysis was performed to evaluate the amount of medial tibial bone loss in each cohort. In addition, a clinical outcomes analysis was performed on the 3 cohorts. The CoCr was noted to have a statistically significant increase in medial tibial bone loss compared with the other 2 cohorts. The all polyethylene cohort had a statistically significantly higher final Knee Society Score and was associated with the least amount of stress shielding. The CoCr tray is the most rigid of 3 implants that were compared in this study. Interestingly, this cohort had the highest amount of medial tibial bone loss. In addition, 1 patient in the CoCr cohort had medial soft tissue irritation which was attributed to a prominent medial tibial tray which required revision surgery to mitigate the symptoms. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Evaluation of carbonate apatite blocks fabricated from dicalcium phosphate dihydrate blocks for reconstruction of rabbit femoral and tibial defects.

    PubMed

    Kanazawa, Masayuki; Tsuru, Kanji; Fukuda, Naoyuki; Sakemi, Yuta; Nakashima, Yasuharu; Ishikawa, Kunio

    2017-06-01

    This study aimed to evaluate in vivo behavior of a carbonate apatite (CO 3 Ap) block fabricated by compositional transformation via a dissolution-precipitation reaction using a calcium hydrogen phosphate dihydrate [DCPD: CaHPO 4 ·2H 2 O] block as a precursor. These blocks were used to reconstruct defects in the femur and tibia of rabbits, using sintered dense hydroxyapatite (HAp) blocks as the control. Both the CO 3 Ap and HAp blocks showed excellent tissue response and good osteoconductivity. HAp block maintained its structure even after 24 weeks of implantation, so no bone replacement of the implant was observed throughout the post-implantation period in either femoral or tibial bone defects. In contrast, CO 3 Ap was resorbed with increasing time after implantation and replaced with new bone. The CO 3 Ap block was resorbed approximately twice as fast at the metaphysis of the proximal tibia than at the epiphysis of the distal femur. The CO 3 Ap block was resorbed at an approximately linear change over time, with complete resorption was estimated by extrapolation of data at approximately 1-1.5 years. Hence, the CO 3 Ap block fabricated in this study has potential value as an ideal artificial bone substitute because of its resorption and subsequent replacement by bone.

  8. Proximal tibial fracture following anterior cruciate ligament reconstruction surgery: a biomechanical analysis of the tibial tunnel as a stress riser.

    PubMed

    Aldebeyan, Wassim; Liddell, Antony; Steffen, Thomas; Beckman, Lorne; Martineau, Paul A

    2017-08-01

    This is the first biomechanical study to examine the potential stress riser effect of the tibial tunnel or tunnels after ACL reconstruction surgery. In keeping with literature, the primary hypothesis tested in this study was that the tibial tunnel acts as a stress riser for fracture propagation. Secondary hypotheses were that the stress riser effect increases with the size of the tunnel (8 vs. 10 mm), the orientation of the tunnel [standard (STT) vs. modified transtibial (MTT)], and with the number of tunnels (1 vs. 2). Tibial tunnels simulating both single bundle hamstring graft (8 mm) and bone-patellar tendon-bone graft (10 mm) either STT or MTT position, as well as tunnels simulating double bundle (DB) ACL reconstruction (7, 6 mm), were drilled in fourth-generation saw bones. These five experimental groups and a control group consisting of native saw bones without tunnels were loaded to failure on a Materials Testing System to simulate tibial plateau fracture. There were no statistically significant differences in peak load to failure between any of the groups, including the control group. The fracture occurred through the tibial tunnel in 100 % of the MTT tunnels (8 and 10 mm) and 80 % of the DB tunnels specimens; however, the fractures never (0 %) occurred through the tibial tunnel of the standard tunnels (8 or 10 mm) (P = 0.032). In the biomechanical model, the tibial tunnel does not appear to be a stress riser for fracture propagation, despite suggestions to the contrary in the literature. Use of a standard, more vertical tunnel decreases the risk of ACL graft compromise in the event of a fracture. This may help to inform surgical decision making on ACL reconstruction technique.

  9. Proximal Tibial Bone Graft

    MedlinePlus

    ... All Site Content AOFAS / FootCareMD / Treatments Proximal Tibial Bone Graft Page Content What is a bone graft? Bone grafts may be needed for various ... the proximal tibia. What is a proximal tibial bone graft? Proximal tibial bone graft (PTBG) is a ...

  10. Investigation on size tolerance of pore defect of girth weld pipe.

    PubMed

    Li, Yan; Shuai, Jian; Xu, Kui

    2018-01-01

    Welding quality control is an important parameter for safe operation of oil and gas pipes, especially for high-strength steel pipes. Size control of welding defect is a bottleneck problem for current pipe construction. As a key part of construction procedure for butt-welding of pipes, pore defects in girth weld is difficult to ignore. A three-dimensional non-linear finite element numerical model is established to study applicability of size control indices based on groove shape and softening phenomenon of material in heat-affected zone of practical pipe girth weld. Taking design criteria of pipe as the basis, basic tensile, extremely tensile and extremely compressive loading conditions are determined for pipe stress analysis, and failure criteria based on flow stress is employed to perform stress analysis for pipe girth weld with pore defect. Results show that pipe girth welding stresses of pores at various radial locations are similar. Whereas, stress for pores of different sharpness varied significantly. Besides, tolerance capability of API 5L X90 grade pipe to pore defect of girth weld is lower than that of API 5L X80 grade pipe, and size control index of 3 mm related to pore defect in current standards is applicable to API 5L X80 and X90 grade girth welded pipes with radially non-sharp pore defects.

  11. Investigation on size tolerance of pore defect of girth weld pipe

    PubMed Central

    Shuai, Jian; Xu, Kui

    2018-01-01

    Welding quality control is an important parameter for safe operation of oil and gas pipes, especially for high-strength steel pipes. Size control of welding defect is a bottleneck problem for current pipe construction. As a key part of construction procedure for butt-welding of pipes, pore defects in girth weld is difficult to ignore. A three-dimensional non-linear finite element numerical model is established to study applicability of size control indices based on groove shape and softening phenomenon of material in heat-affected zone of practical pipe girth weld. Taking design criteria of pipe as the basis, basic tensile, extremely tensile and extremely compressive loading conditions are determined for pipe stress analysis, and failure criteria based on flow stress is employed to perform stress analysis for pipe girth weld with pore defect. Results show that pipe girth welding stresses of pores at various radial locations are similar. Whereas, stress for pores of different sharpness varied significantly. Besides, tolerance capability of API 5L X90 grade pipe to pore defect of girth weld is lower than that of API 5L X80 grade pipe, and size control index of 3 mm related to pore defect in current standards is applicable to API 5L X80 and X90 grade girth welded pipes with radially non-sharp pore defects. PMID:29364986

  12. Tibial tunnel aperture location during single-bundle posterior cruciate ligament reconstruction: comparison of tibial guide positions.

    PubMed

    Shin, Young-Soo; Han, Seung-Beom; Hwang, Yeok-Ku; Suh, Dong-Won; Lee, Dae-Hee

    2015-05-01

    We aimed to compare posterior cruciate ligament (PCL) tibial tunnel location after tibial guide insertion medial (between the PCL remnant and the medial femoral condyle) and lateral (between the PCL remnant and the anterior cruciate ligament) to the PCL stump as determined by in vivo 3-dimensional computed tomography (3D-CT). Tibial tunnel aperture location was analyzed by immediate postoperative in vivo CT in 66 patients who underwent single-bundle PCL reconstruction, 31 by over-the-PCL and 35 by under-the-PCL tibial guide insertion techniques. Tibial tunnel positions were measured in the medial to lateral and proximal to distal directions of the posterior proximal tibia. The center of the tibial tunnel aperture was located more laterally (by 2.7 mm) in the over-the-PCL group than in the under-the-PCL group (P = .040) and by a relative percentage (absolute value/tibial width) of 3.2% (P = .031). Tibial tunnel positions in the proximal to distal direction, determined by absolute value and relative percentage, were similar in the 2 groups. Tibial tunnel apertures were located more laterally after lateral-to-the-PCL tibial guide insertion than after medial-to-the-PCL tibial guide insertion. There was, however, no significant difference between these techniques in distance from the joint line to the tibial tunnel aperture. Insertion lateral to the PCL stump may result in better placement of the PCL in its anatomic footprint. Level III, retrospective comparative study. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  13. Transplantation of free tibial periosteal grafts for the repair of articular cartilage defect: An experimental study

    PubMed Central

    Singh, Ravijot; Chauhan, Vijendra; Chauhan, Neena; Sharma, Sansar

    2009-01-01

    Background: Articular chondrocytes have got a long lifespan but rarely divides after maturity. Thus, an articular cartilage has a limited capacity for repair. Periosteal grafts have chondrogenic potential and have been used to repair defects in the articular cartilage. The purpose of the present study is to investigate the differentiation of free periosteal grafts in the patellofemoral joint where the cambium layer faces the subchondral bone and to investigate the applicability of periosteal grafts in the reconstruction of articular surfaces. Materials and Methods: The study was carried out over a period of 1 year on 25 adult, male Indian rabbits after obtaining permission from the institutional animal ethical committee. A full-thickness osteochondral defect was created by shaving off the whole articular cartilage of the patella of the left knee. The defect thus created was grafted with free periosteal graft. The patella of the right knee was taken as a control where no grafting was done after shaving off the articular cartilage. The first animal was used to study the normal histology of the patellar articular cartilage and periosteum obtained from the medial surface of tibial condyle. Rest 24 animals were subjected to patellectomy, 4 each at serial intervals of 2, 4, 8, 16, 32 and 48 weeks and the patellar articular surfaces were examined macroscopically and histologically. Results: The grafts got adherent to the underlying patellar articular surface at the end of 4 weeks. Microscopically, graft incorporation could be appreciated at 4 weeks. Mesenchymal cells of the cambium layer were seen differentiating into chondrocytes by the end of 4 weeks in four grafts (100%) and they were arranged in a haphazard manner. Till the end of 8 weeks, the cellular arrangement was mostly wooly. At 16 weeks, one graft (25%) had wooly arrangement of chondrocytes and three grafts (75%) had columnar formation of cells. Same percentage was maintained at 32 weeks. Four grafts (100%) at

  14. Tissue-engineered bone constructed in a bioreactor for repairing critical-sized bone defects in sheep.

    PubMed

    Li, Deqiang; Li, Ming; Liu, Peilai; Zhang, Yuankai; Lu, Jianxi; Li, Jianmin

    2014-11-01

    Repair of bone defects, particularly critical-sized bone defects, is a considerable challenge in orthopaedics. Tissue-engineered bones provide an effective approach. However, previous studies mainly focused on the repair of bone defects in small animals. For better clinical application, repairing critical-sized bone defects in large animals must be studied. This study investigated the effect of a tissue-engineered bone for repairing critical-sized bone defect in sheep. A tissue-engineered bone was constructed by culturing bone marrow mesenchymal-stem-cell-derived osteoblast cells seeded in a porous β-tricalcium phosphate ceramic (β-TCP) scaffold in a perfusion bioreactor. A critical-sized bone defect in sheep was repaired with the tissue-engineered bone. At the eighth and 16th week after the implantation of the tissue-engineered bone, X-ray examination and histological analysis were performed to evaluate the defect. The bone defect with only the β-TCP scaffold served as the control. X-ray showed that the bone defect was successfully repaired 16 weeks after implantation of the tissue-engineered bone; histological sections showed that a sufficient volume of new bones formed in β-TCP 16 weeks after implantation. Eight and 16 weeks after implantation, the volume of new bones that formed in the tissue-engineered bone group was more than that in the β-TCP scaffold group (P < 0.05). Tissue-engineered bone improved osteogenesis in vivo and enhanced the ability to repair critical-sized bone defects in large animals.

  15. Management of Anterior Skull Base Defect Depending on Its Size and Location

    PubMed Central

    Bernal-Sprekelsen, Manuel; Rioja, Elena; Enseñat, Joaquim; Enriquez, Karla; Viscovich, Liza; Agredo-Lemos, Freddy Enrique; Alobid, Isam

    2014-01-01

    Introduction. We present our experience in the reconstruction of these leaks depending on their size and location. Material and Methods. Fifty-four patients who underwent advanced skull base surgery (large defects, >20 mm) and 62 patients with CSF leaks of different origin (small, 2–10 mm, and midsize, 11–20 mm, defects) were included in the retrospective study. Large defects were reconstructed with a nasoseptal pedicled flap positioned on fat and fascia lata. In small and midsized leaks. Fascia lata in an underlay position was used for its reconstruction covered with mucoperiosteum of either the middle or the inferior turbinate. Results. The most frequent etiology for small and midsized defects was spontaneous (48.4%), followed by trauma (24.2%), iatrogenic (5%). The success rate after the first surgical reconstruction was 91% and 98% in large skull base defects and small/midsized, respectively. Rescue surgery achieved 100%. Conclusions. Endoscopic surgery for any type of skull base defect is the gold standard. The size of the defects does not seem to play a significant role in the success rate. Fascia lata and mucoperiosteum of the turbinate allow a two-layer reconstruction of small and midsized defects. For larger skull base defects, a combination of fat, fascia lata, and nasoseptal pedicled flaps provides a successful reconstruction. PMID:24895567

  16. Tibial plateau fracture following gracilis-semitendinosus anterior cruciate ligament reconstruction: The tibial tunnel stress-riser.

    PubMed

    Sundaram, R O; Cohen, D; Barton-Hanson, N

    2006-06-01

    Tibial plateau fractures following anterior cruciate ligament (ACL) reconstruction are extremely rare. This is the first reported case of a tibial plateau fracture following four-strand gracilis-semitendinosus autograft ACL reconstruction. The tibial tunnel alone may behave as a stress riser which can significantly reduce bone strength.

  17. USE OF BIOCERAMICS IN FILLING BONE DEFECTS

    PubMed Central

    Garrido, Carlos Antõnio; Sampaio, Tania Clarete Fonseca Vieira Sales

    2015-01-01

    Objective: To present the results from using biological ceramics for filling bone defects resulting from post-traumatic or orthopedic injuries. Methods: Thirty-six patients with bone defects caused by trauma or orthopedic injury were evaluated. Nineteen patients were male (52.8%) and 17 were female (47.2%). Their ages ranged from 19 to 84 years, with a mean of 45.7 years and median of 37 years. Only patients with defects that required at least five grams of biological ceramic were included. Eighteen cases were classified as orthopedic: bone defects were observed in 11 cases of total hip arthroplasty; one case of primary total hip arthroplasty, due to coxarthrosis; five cases of femoral or tibial open wedge osteotomy; and one case of tarsal arthrodesis. There were 18 cases of trauma-related defects; uninfected pseudarthrosis, eight cases; recent fractures of the tibial plateau with compression of the spongy bone, three cases; and exposed fractures treated with external fixators, seven cases. The surgical technique consisted of curetting and debriding the injury until bone suitable for grafting was found. Biological ceramic was then used to fill the defect and some kind of fixation was applied. Results: Among the 36 patients evaluated, it was seen that 35 (97.2%) presented integration of the biological ceramic, while one case of open fracture treated with external fixation had poor integration of the biological ceramic. Conclusion: Treatment of bone defects of orthopedic or post-traumatic etiology using a phosphocalcium ceramic composed of hydroxyapatite was shown to be a practical, effective and safe method. PMID:27022576

  18. Tibial Tray Thickness Significantly Increases Medial Tibial Bone Resorption in Cobalt-Chromium Total Knee Arthroplasty Implants.

    PubMed

    Martin, J Ryan; Watts, Chad D; Levy, Daniel L; Miner, Todd M; Springer, Bryan D; Kim, Raymond H

    2017-01-01

    Stress shielding is an uncommon complication associated with primary total knee arthroplasty. Patients are frequently identified radiographically with minimal clinical symptoms. Very few studies have evaluated risk factors for postoperative medial tibial bone loss. We hypothesized that thicker cobalt-chromium tibial trays are associated with increased bone loss. We performed a retrospective review of 100 posterior stabilized, fixed-bearing total knee arthroplasty where 50 patients had a 4-mm-thick tibial tray (thick tray cohort) and 50 patients had a 2.7-mm-thick tibial tray (thin tray cohort). A clinical evaluation and a radiographic assessment of medial tibial bone loss were performed on both cohorts at a minimum of 2 years postoperatively. Mean medial tibial bone loss was significantly higher in the thick tray cohort (1.07 vs 0.16 mm; P = .0001). In addition, there were significantly more patients with medial tibial bone loss in the thick tray group compared with the thin tray group (44% vs 10%, P = .0002). Despite these differences, there were no statistically significant differences in range of motion, knee society score, complications, or revision surgeries performed. A thicker cobalt-chromium tray was associated with significantly more medial tibial bone loss. Despite these radiographic findings, we found no discernable differences in clinical outcomes in our patient cohort. Further study and longer follow-up are needed to understand the effects and clinical significance of medial tibial bone loss. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. ACL double-bundle reconstruction with one tibial tunnel provides equal stability compared to two tibial tunnels.

    PubMed

    Drews, Björn Holger; Seitz, Andreas Martin; Huth, Jochen; Bauer, Gerhard; Ignatius, Anita; Dürselen, Lutz

    2017-05-01

    The purpose of this study was to investigate whether an anterior cruciate ligament (ACL) double-bundle reconstruction with one tibial tunnel displays the same in vitro stability as a conventional double-bundle reconstruction with two tibial tunnels when using the same tensioning protocol. In 11 fresh-frozen cadaveric knees, ACL double-bundle reconstruction with one and two tibial tunnels was performed. The two grafts were tightened using 80 N in different flexion angles (anteromedial-bundle at 60° and posterolateral-bundle at 15°). Anterior tibial translation (134 N) and translation with combined rotatory and valgus loads (10 Nm valgus stress and 4 Nm internal tibial torque) were determined at 0°, 30°, 60° and 90° flexion. Measurements were taken in intact ACL, resected ACL, three-tunnel reconstruction and four-tunnel reconstruction. Additionally, the tension on the grafts was determined. Student's t test was performed for statistical analysis of the related samples. Significance was set at p < 0.017 according to Bonferroni correction. The two reconstructive techniques displayed no significant differences in comparison with the intact ACL in anterior tibial translation at 0°, 60° and 90° of flexion. The same results were obtained for the anterior tibial translation with a combined rotatory load at 60° and 90°. When directly comparing both reconstructive techniques, there were no significant differences for the anterior tibial translation and combined rotatory load at all flexion angles. The measured tension on grafts displayed similar load sharing between both bundles. Except at full extension, both grafts displayed a significantly different tension increase under anterior tibial translation for both techniques (p = 0.0086). Tightening both bundles in ACL double-bundle reconstruction with one or two tibial tunnels in different flexion angles achieved comparable restoration of stability, although there was different load sharing on the bundles

  20. Tibial lengthening over humeral and tibial intramedullary nails in patients with sequelae of poliomyelitis: a comparative study.

    PubMed

    Chen, Daoyun; Chen, Jianmin; Jiang, Yao; Liu, Fanggang

    2011-06-01

    Leg discrepancy is common after poliomyelitis. Tibial lengthening is an effective way to solve this problem. It is believed lengthening over a tibial intramedullary nail can provide a more comfortable lengthening process than by the conventional technique. However, patients with sequelae of poliomyelitis typically have narrow intramedullary canals allowing limited space for inserting a tibial intramedullary nail and Kirschner wires. To overcome this problem, we tried using humeral nails instead of tibial nails in the lengthening procedure. In this study, we used humeral nails in 20 tibial lengthening procedures and compared the results with another group of patients who were treated with tibial lengthening over tibial intramedullary nails. The mean consolidation index, percentage of increase and external fixation index did not show significant differences between the two groups. However, less blood loss and shorter operating time were noted in the humeral nail group. More patients encountered difficulty with the inserted intramedullary nail in the tibial nail group procedure. The complications did not show a statistically significant difference between the two techniques on follow-up. In conclusion, we found the humeral nail lengthening technique was more suitable in leg discrepancy patients with sequelae of poliomyelitis.

  1. Cranial tibial wedge osteotomy: a technique for eliminating cranial tibial thrust in cranial cruciate ligament repair.

    PubMed

    Slocum, B; Devine, T

    1984-03-01

    Cranial tibial wedge osteotomy, surgical technique for cranial cruciate ligament rupture, was performed on 19 stifles in dogs. This procedure leveled the tibial plateau, thus causing weight-bearing forces to be compressive and eliminating cranial tibial thrust. Without cranial tibial thrust, which was antagonistic to the cranial cruciate ligament and its surgical reconstruction, cruciate ligament repairs were allowed to heal without constant loads. This technique was meant to be used as an adjunct to other cranial cruciate ligament repair techniques.

  2. Tibial component coverage based on bone mineral density of the cut tibial surface during unicompartmental knee arthroplasty: clinical relevance of the prevention of tibial component subsidence.

    PubMed

    Lee, Yong Seuk; Yun, Ji Young; Lee, Beom Koo

    2014-01-01

    An optimally implanted tibial component during unicompartmental knee arthroplasty would be flush with all edges of the cut tibial surface. However, this is often not possible, partly because the tibial component may not be an ideal shape or because the ideal component size may not be available. In such situations, surgeons need to decide between component overhang and underhang and as to which sites must be covered and which sites could be undercovered. The objectives of this study were to evaluate the bone mineral density of the cut surface of the proximal tibia around the cortical rim and to compare the bone mineral density according to the inclusion of the cortex and the site-specific matched evaluation. One hundred and fifty consecutive patients (100 men and 50 women) were enrolled in this study. A quantitative computed tomography was used to determine the bone density of the cut tibial surface. Medial and lateral compartments were divided into anterior, middle, and posterior regions, and these three regions were further subdivided into two regions according to containment of cortex. The site-specific matched comparison (medial vs. lateral) of bone mineral density was performed. In medial sides, the mid-region, including the cortex, showed the highest bone mineral density in male and female patients. The posterior region showed the lowest bone mineral density in male patients, and the anterior and posterior regions showed the lowest bone mineral density in female patients. Regions including cortex showed higher bone mineral density than pure cancellous regions in medial sides. In lateral sides, posterior regions including cortex showed highest bone mineral density with statistical significance in both male and female patients. The anterior region showed the lowest bone mineral density in both male and female patients. The mid-region of the medial side and the posterior region of the lateral side are relatively safe without cortical coverage when the component

  3. Stretched size of atrial septal defect predicted by intracardiac echocardiography.

    PubMed

    Lin, Ming-Chih; Fu, Yun-Ching; Jan, Sheng-Ling; Ho, Chi-Lin; Hwang, Betau

    2010-01-01

    The stretched size of an atrial septal defect (ASD) is important for device selection during transcatheter closure. However, balloon sizing carries potential risks such as hypotension, bradycardia, or laceration of the atrial septum. The aim of the present study was to investigate the accuracy of the predicted stretched size of ASD by intracardiac echocardiography (ICE). From December 2004 to November 2007, 136 consecutive patients with single secundum type ASD undergoing transcatheter closure of their defect using the Amplatzer septal occluder under ICE guidance were enrolled for analysis. There were 43 males and 93 females. The age ranged from 2.2 to 79.1 years with a median age of 13.4 years. The body weight ranged from 12.1 to 93.2 kg with a median body weight of 45.8 kg. The stretched size of ASD measured by a sizing plate was considered as the standard. ASD sizes measured by ICE in bicaval and short-axis views predicted the stretched size by formulae derived from linear regressions. The predicted stretched sizes obtained using 2 formulae, 1.34 x radicalbicaval xshort axis (formula 1) and 1.22 x larger diameter (formula 2), exhibited good agreement with the standard stretched size with Kappa values of 0.91 and 0.90, respectively. The accuracy rate of predicted stretched sizes within 2 mm, 3 mm, and 4 mm range of the standard size were 32.8%, 45.4%, and 57.7% (formula 1) and 33.1%, 50%, and 63.2% (formula 2). The stretched size of ASD predicted by ICE exhibited good agreement with the standard stretched size. This prediction provides helpful information, especially if balloon sizing cannot be adequately performed.

  4. Effect of Tibial Plateau Levelling Osteotomy on Cranial Tibial Subluxation in the Feline Cranial Cruciate Deficient Stifle Joint: An Ex Vivo Experimental Study.

    PubMed

    Bilmont, A; Retournard, M; Asimus, E; Palierne, S; Autefage, A

    2018-06-11

     This study evaluated the effects of tibial plateau levelling osteotomy on cranial tibial subluxation and tibial rotation angle in a model of feline cranial cruciate ligament deficient stifle joint.  Quadriceps and gastrocnemius muscles were simulated with cables, turnbuckles and a spring in an ex vivo limb model. Cranial tibial subluxation and tibial rotation angle were measured radiographically before and after cranial cruciate ligament section, and after tibial plateau levelling osteotomy, at postoperative tibial plateau angles of +5°, 0° and -5°.  Cranial tibial subluxation and tibial rotation angle were not significantly altered after tibial plateau levelling osteotomy with a tibial plateau angle of +5°. Additional rotation of the tibial plateau to a tibial plateau angle of 0° and -5° had no significant effect on cranial tibial subluxation and tibial rotation angle, although 2 out of 10 specimens were stabilized by a postoperative tibial plateau angle of -5°. No stabilization of the cranial cruciate ligament deficient stifle was observed in this model of the feline stifle, after tibial plateau levelling osteotomy.  Given that stabilization of the cranial cruciate ligament deficient stifle was not obtained in this model, simple transposition of the tibial plateau levelling osteotomy technique from the dog to the cat may not be appropriate. Schattauer GmbH Stuttgart.

  5. The critical size of focal articular cartilage defects is associated with strains in the collagen fibers.

    PubMed

    Heuijerjans, A; Wilson, W; Ito, K; van Donkelaar, C C

    2017-12-01

    The size of full-thickness focal cartilage defect is accepted to be predictive of its fate, but at which size threshold treatment is required is unclear. Clarification of the mechanism behind this threshold effect will help determining when treatment is required. The objective was to investigate the effect of defect size on strains in the collagen fibers and the non-fibrillar matrix of surrounding cartilage. These strains may indicate matrix disruption. Tissue deformation into the defect was expected, stretching adjacent superficial collagen fibers, while an osteochondral implant was expected to prevent these deformations. Finite element simulations of cartilage/cartilage contact for intact, 0.5 to 8mm wide defects and 8mm implant cases were performed. Impact, a load increase to 2MPa in 1ms, and creep loading, a constant load of 0.5MPa for 900s, scenarios were simulated. A composition-based material model for articular cartilage was employed. Impact loading caused low strain levels for all models. Creep loading increased deviatoric strains and collagen strains in the surrounding cartilage. Deviatoric strains increased gradually with defect size, but the surface area at which collagen fiber strains exceeded failure thresholds, abruptly increased for small increases of defect size. This was caused by a narrow distribution of collagen fiber strains resulting from the non-linear stiffness of the fibers. We postulate this might be the mechanism behind the existence of a critical defect size. Filling of the defect with an implant reduced deviatoric and collagen fiber strains towards values for intact cartilage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. The Valgus Inclination of the Tibial Component Increases the Risk of Medial Tibial Condylar Fractures in Unicompartmental Knee Arthroplasty.

    PubMed

    Inoue, Shinji; Akagi, Masao; Asada, Shigeki; Mori, Shigeshi; Zaima, Hironori; Hashida, Masahiko

    2016-09-01

    Medial tibial condylar fractures (MTCFs) are a rare but serious complication after unicompartmental knee arthroplasty. Although some surgical pitfalls have been reported for MTCFs, it is not clear whether the varus/valgus tibial inclination contributes to the risk of MTCFs. We constructed a 3-dimensional finite elemental method model of the tibia with a medial component and assessed stress concentrations by changing the inclination from 6° varus to 6° valgus. Subsequently, we repeated the same procedure adding extended sagittal bone cuts of 2° and 10° in the posterior tibial cortex. Furthermore, we calculated the bone volume that supported the tibial component, which is considered to affect stress distribution in the medial tibial condyle. Stress concentrations were observed on the medial tibial metaphyseal cortices and on the anterior and posterior tibial cortices in the corner of cut surfaces in all models; moreover, the maximum principal stresses on the posterior cortex were larger than those on the anterior cortex. The extended sagittal bone cuts in the posterior tibial cortex increased the stresses further at these 3 sites. In the models with a 10° extended sagittal bone cut, the maximum principal stress on the posterior cortex increased as the tibial inclination changed from 6° varus to 6° valgus. The bone volume decreased as the inclination changed from varus to valgus. In this finite element method, the risk of MTCFs increases with increasing valgus inclination of the tibial component and with increased extension of the sagittal cut in the posterior tibial cortex. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Association of baseline knee bone size, cartilage volume, and body mass index with knee cartilage loss over time: a longitudinal study in younger or middle-aged adults.

    PubMed

    Antony, Benny; Ding, Changhai; Stannus, Oliver; Cicuttini, Flavia; Jones, Graeme

    2011-09-01

    To determine the association of knee bone size, cartilage volume, and body mass index (BMI) at baseline with knee cartilage loss over 2 years in younger or middle-aged adults. A total of 324 subjects (mean age 45 yrs, range 26-61) were measured at baseline and about 2 years later. Knee cartilage volume and bone size were determined using T1-weighted fat-saturated magnetic resonance imaging. In multivariable analysis, baseline knee bone size was negatively associated with annual change in knee cartilage volume at medial and lateral tibial sites (ß = -0.62% to -0.47%/cm(2), all p < 0.001). The associations disappeared at medial tibial site after adjustment for baseline cartilage volume and became of borderline statistical significance at lateral tibial site after adjustment for both baseline cartilage volume and osteophytes (ß = -0.29, p = 0.059). Baseline knee cartilage volume was consistently and negatively associated with annual change in knee cartilage volume at all 3 medial tibial, lateral tibial, and patellar sites (ß = -4.41% to -1.37%/ml, all p < 0.001). Baseline BMI was negatively associated with an annual change in knee cartilage volume, but only in subjects within the upper tertile of baseline cartilage volume, even after adjusting for cartilage defects (ß = -0.16% to -0.34%/kg/m(2), all p < 0.05). Our study suggests that both higher baseline tibial bone area and knee cartilage volume (most likely due to cartilage swelling) are associated with greater knee cartilage loss over 2 years. A higher BMI was associated with greater knee cartilage loss only in subjects with higher baseline cartilage volume.

  8. Size and Location of Defects at the Coupling Interface Affect Lithotripter Performance

    PubMed Central

    Li, Guangyan; Williams, James C.; Pishchalnikov, Yuri A.; Liu, Ziyue; McAteer, James A.

    2012-01-01

    OBJECTIVE To determine how the size and location of coupling defects caught between the therapy head of a lithotripter and the skin of a surrogate patient (acoustic window of a test chamber) affect the features of shock waves responsible for stone breakage. METHODS Model defects were placed in the coupling gel between the therapy head of a Dornier Compact-S electromagnetic lithotripter and the Mylar window of a water-filled coupling test system. A fiber-optic hydrophone was used to measure acoustic pressures and map the lateral dimensions of the focal zone of the lithotripter. The effect of coupling conditions on stone breakage was assessed using Gypsum model stones. RESULTS Stone breakage decreased in proportion to the area of the coupling defect; a centrally located defect blocking only 18% of the transmission area reduced stone breakage by an average of almost 30%. The effect on stone breakage was greater for defects located on-axis and decreased as the defect was moved laterally; an 18% defect located near the periphery of the coupling window (2.0 cm off-axis) reduced stone breakage by only ~15% compared to when coupling was completely unobstructed. Defects centered within the coupling window acted to narrow the focal width of the lithotripter; an 8.2% defect reduced the focal width ~30% compared to no obstruction (4.4 mm versus 6.5 mm). Coupling defects located slightly off center disrupted the symmetry of the acoustic field; an 18% defect positioned 1.0 cm off-axis shifted the focus of maximum positive pressure ~1.0 mm laterally. Defects on and off-axis imposed a significant reduction in the energy density of shock waves across the focal zone. CONCLUSIONS In addition to blocking the transmission of shock wave energy, coupling defects also disrupt the properties of shock waves that play a role in stone breakage, including the focal width of the lithotripter and the symmetry of the acoustic field; the effect is dependent on the size and location of defects

  9. Detection of small-size solder ball defects through heat conduction analysis

    NASA Astrophysics Data System (ADS)

    Zhou, Xiuyun; Chen, Yaqiu; Lu, Xiaochuan

    2018-02-01

    Aiming to solve the defect detection problem of a small-size solder ball in the high density chip, heat conduction analysis based on eddy current pulsed thermography is put forward to differentiate various defects. With establishing the 3D finite element model about induction heating, defects such as cracks and void can be distinguished by temperature difference resulting from heat conduction. Furthermore, the experiment of 0.4 mm-diameter solder balls with different defects is carried out to prove that crack and void solder can be distinguished. Three kinds of crack length on a gull-wing pin are selected, including 0.24 mm, 1.2 mm, and 2.16 mm, to verify that the small defect can be discriminated. Both the simulation study and experiment result show that the heat conduction analysis method is reliable and convenient.

  10. Effects of osteochondral defect size on cartilage regeneration using a double-network hydrogel.

    PubMed

    Higa, Kotaro; Kitamura, Nobuto; Goto, Keiko; Kurokawa, Takayuki; Gong, Jian Ping; Kanaya, Fuminori; Yasuda, Kazunori

    2017-05-22

    There has been increased interest in one-step cell-free procedures to avoid the problems related to cell manipulation and its inherent disadvantages. We have studied the chondrogenic induction ability of a PAMPS/PDMAAm double-network (DN) gel and found it to induce chondrogenesis in animal osteochondral defect models. The purpose of this study was to investigate whether the healing process and the degree of cartilage regeneration induced by the cell-free method using DN gel are influenced by the size of osteochondral defects. A total of 63 mature female Japanese white rabbits were used in this study, randomly divided into 3 groups of 21 rabbits each. A 2.5-mm diameter osteochondral defect was created in the femoral trochlea of the patellofemoral joint of bilateral knees in Group I, a 4.3-mm osteochondral defect in Group II, and a 5.8-mm osteochondral defect in Group III. In the right knee of each animal, a DN gel plug was implanted so that a vacant space of 2-mm depth was left above the plug. In the left knee, we did not conduct any treatment to obtain control data. Animals were sacrificed at 2, 4, and 12 weeks after surgery, and gross and histological evaluations were made. The present study demonstrated that all sizes of the DN gel implanted defects as well as the 2.5mm untreated defects showed cartilage regeneration at 4 and 12 weeks. The 4.3-mm and 5.8-mm untreated defects did not show cartilage regeneration during the 12-week period. The quantitative score reported by O'Driscoll et al. was significantly higher in the 4.3-mm and 5.8-mm DN gel-implanted defects than the untreated defects at 4 and 12 weeks (p < 0.05). The 2.5-mm and 4.3-mm DN gel implanted defects maintained relatively high macroscopic and histological scores for the 12-week implantation period, while the histological score of the 5.8-mm DN gel implanted defect had decreased somewhat but statistically significantly at 12 weeks (p = 0.0057). The DN gel induced cartilage regeneration in

  11. [Tibial periostitis ("medial tibial stress syndrome")].

    PubMed

    Fournier, Pierre-Etienne

    2003-06-01

    Medial tibial stress syndrome is characterised by complaints along the posteromedial tibia. Runners and athletes involved in jumping activities may develop this syndrome. Increased stress to stabilize the foot especially when excessive pronation is present explain the occurrence this lesion.

  12. Free flap reconstructions of tibial fractures complicated after internal fixation.

    PubMed

    Nieminen, H; Kuokkanen, H; Tukiainen, E; Asko-Seljavaara, S

    1995-04-01

    The cases of 15 patients are presented where microvascular soft-tissue reconstructions became necessary after internal fixation of tibial fractures. Primarily, seven of the fractures were closed. Eleven fractures had originally been treated by open reduction and internal fixation using plates and screws, and four by intramedullary nailing. All of the patients suffered from postoperative complications leading to exposure of the bone or fixation material. The internal fixation material was removed and radical revision of dead and infected tissue was carried out in all cases. Soft tissue reconstruction was performed using a free microvascular muscle flap (11 latissimus dorsi, three rectus abdominis, and one gracilis). In eight cases the nonunion of the fracture indicated external fixation. The microvascular reconstruction was successful in all 15 patients. In one case the recurrence of deep infection finally indicated a below-knee amputation. In another case, chronic infection with fistulation recurred postoperatively. After a mean follow-up of 26 months the soft tissue coverage was good in all the remaining 13 cases. All the fractures united. Microvascular free muscle flap reconstruction of the leg is regarded as a reliable method for salvaging legs with large soft-tissue defects or defects in the distal leg. If after internal fixation of the tibial fracture the osteosynthesis material or fracture is exposed, reconstruction of the soft-tissue can successfully be performed by free flap transfer. By radical revision, external fixation, bone grafting, and a free flap the healing of the fracture can be achieved.

  13. A comparison of defect size and film quality obtained from Film digitized image and digital image radiographs

    NASA Astrophysics Data System (ADS)

    Kamlangkeng, Poramate; Asa, Prateepasen; Mai, Noipitak

    2014-06-01

    Digital radiographic testing is an acceptable premature nondestructive examination technique. Its performance and limitation comparing to the old technique are still not widely well known. In this paper conducted the study on the comparison of the accuracy of the defect size measurement and film quality obtained from film and digital radiograph techniques by testing in specimens and known size sample defect. Initially, one specimen was built with three types of internal defect; which are longitudinal cracking, lack of fusion, and porosity. For the known size sample defect, it was machined various geometrical size for comparing the accuracy of the measuring defect size to the real size in both film and digital images. To compare the image quality by considering at smallest detectable wire and the three defect images. In this research used Image Quality Indicator (IQI) of wire type 10/16 FE EN BS EN-462-1-1994. The radiographic films were produced by X-ray and gamma ray using Kodak AA400 size 3.5x8 inches, while the digital images were produced by Fuji image plate type ST-VI with 100 micrometers resolution. During the tests, a radiator GE model MF3 was implemented. The applied energy is varied from 120 to 220 kV and the current from 1.2 to 3.0 mA. The intensity of Iridium 192 gamma ray is in the range of 24-25 Curie. Under the mentioned conditions, the results showed that the deviation of the defect size measurement comparing to the real size obtained from the digital image radiographs is below than that of the film digitized, whereas the quality of film digitizer radiographs is higher in comparison.

  14. Size and location of defects at the coupling interface affect lithotripter performance.

    PubMed

    Li, Guangyan; Williams, James C; Pishchalnikov, Yuri A; Liu, Ziyue; McAteer, James A

    2012-12-01

    Study Type--Therapy (case series) Level of Evidence 4. What's known on the subject? and What does the study add? In shock wave lithotripsy air pockets tend to get caught between the therapy head of the lithotripter and the skin of the patient. Defects at the coupling interface hinder the transmission of shock wave energy into the body, reducing the effectiveness of treatment. This in vitro study shows that ineffective coupling not only blocks the transmission of acoustic pulses but also alters the properties of shock waves involved in the mechanisms of stone breakage, with the effect dependent on the size and location of defects at the coupling interface. • To determine how the size and location of coupling defects caught between the therapy head of a lithotripter and the skin of a surrogate patient (i.e. the acoustic window of a test chamber) affect the features of shock waves responsible for stone breakage. • Model defects were placed in the coupling gel between the therapy head of a Dornier Compact-S electromagnetic lithotripter (Dornier MedTech, Kennesaw, GA, USA) and the Mylar (biaxially oriented polyethylene terephthalate) (DuPont Teijin Films, Chester, VA, USA) window of a water-filled coupling test system. • A fibre-optic probe hydrophone was used to measure acoustic pressures and map the lateral dimensions of the focal zone of the lithotripter. • The effect of coupling conditions on stone breakage was assessed using gypsum model stones. • Stone breakage decreased in proportion to the area of the coupling defect; a centrally located defect blocking only 18% of the transmission area reduced stone breakage by an average of almost 30%. • The effect on stone breakage was greater for defects located on-axis and decreased as the defect was moved laterally; an 18% defect located near the periphery of the coupling window (2.0 cm off-axis) reduced stone breakage by only ~15% compared to when coupling was completely unobstructed. • Defects centred

  15. Minimally invasive fixation in tibial plateau fractures using an pre-operative and intra-operative real size 3D printing.

    PubMed

    Giannetti, Silvio; Bizzotto, Nicola; Stancati, Andrea; Santucci, Attilio

    2017-03-01

    The purpose of our study was to compare the outcome after minimally invasive reconstruction and internal fixation with and without the use of pre- and intra-operative real size 3D printing for patients with displaced tibial plateau fractures (TPFs). We prospectively followed up 40 consecutive adult patients with closed TPF who underwent surgical treatment of reconstruction of the tibial plateau with the use of minimally invasive fixation. Sixteen patients (group 1) were operated using a pre-operative and intra-operative real size 3D-model, while 24 patients (group 2) were operated without 3D-model printing, but using only pre-operative and intra-operative 3D Tc-scan images. The mean operating time was 148.2±15.9min for group 1 and 174.5±22.2min for group 2 (p=0.041). In addition, the mean intraoperative blood loss was less in group 1 (520mL) than in group 2 (546mL) (p=0.534). After discharge, all patients were followed up at 6 weeks, 12 weeks, 6 months, 1year and then every year post surgically and radiographic evaluation was carried out each time using clinical and radiological Rasmussen's score, with no significant differences between the two groups. Two patients (group 2) developed infection which resolved within 3 weeks after usage of antibiotics. Neither superficial nor deep infections were present in group 1. In all patients, no non-union occurred. No intraoperative, perioperative, or postoperative complications, such as loss of valgus correction, bone fractures, or metallic plate failures were detected at follow-up. In patients operated with the use of 3D-model printing, we found a significant reduction in surgical time. Moreover, the technique without a 3D-model increased the patient's and the surgeon's exposure to radiation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Effect of Resorbable Collagen Plug on Bone Regeneration in Rat Critical-Size Defect Model.

    PubMed

    Liu, Weiqing; Kang, Ning; Dong, Yuliang; Guo, Yuchen; Zhao, Dan; Zhang, Shiwen; Zhou, Liyan; Seriwatanachai, Dutmanee; Liang, Xing; Yuan, Quan

    2016-04-01

    The purpose of this investigation was to examine the effect of resorbable collagen plug (RCP) on bone regeneration in rat calvarial critical-size defects. About 5-mm-diameter calvarial defects were created in forty 12-week-old male Sprague-Dawley rats and implanted with or without RCP. Animals were killed at 1, 2, 4, and 8 weeks postoperatively. After being killed, specimens were collected and subjected to micro-computed tomography (μCT) and histological analysis. The μCT showed a significant increase of newly formed bone volume/tissue volume in RCP-implanted defect compared with controls at all designated time points. After 8 weeks, the defects implanted with RCP displayed almost complete closure. Hematoxylin and eosin staining of the decalcified sections confirmed these observations and evidenced active bone regeneration in the RCP group. In addition, Masson's trichrome staining demonstrated that RCP implantation accelerated the process of collagen maturation. The RCP enhances bone regeneration in rat critical-size cranial defects, which suggest it might be a desired material for bone defect repair.

  17. Total knee arthroplasty in patients with a prior fracture of the tibial plateau.

    PubMed

    Weiss, Nicholas G; Parvizi, Javad; Trousdale, Robert T; Bryce, Rex D; Lewallen, David G

    2003-02-01

    A fracture of the tibial plateau may predispose the knee to the development of posttraumatic arthritis. Malunion, intra-articular chondro-osseous defects, limb malalignment, retained internal fixation devices, and poor surrounding soft tissues may in turn compromise the outcome of total knee arthroplasty. The aim of our study was to evaluate the results of total knee arthroplasty in patients with a previous fracture of the tibial plateau. The results of sixty-two condylar total knee arthroplasties performed with cement, from 1988 to 1999, in sixty-two patients with a previous fracture of the tibial plateau were reviewed. The fracture of the tibial plateau had been treated by open reduction and internal fixation in thirty-eight knees, external fixation in one knee, and nonoperatively in twenty-three knees. There were forty women and twenty-two men with an average age of sixty-three years at the time of the arthroplasty. Knee Society scores were recorded preoperatively and at the time of follow-up, at an average of 4.7 years, and complications were noted. No patient was lost to follow-up. The mean Knee Society scores improved significantly (p < 0.0001), from 43.9 points for pain and 52 points for function preoperatively to 82.9 and 84 points, respectively, at the time of the latest follow-up. There were thirteen reoperations, which included manipulation with the patient under anesthesia (five knees), wound revision (three knees), and component revision (five knees). There were six intraoperative complications (10%). A postoperative complication occurred in sixteen knees (26%). The vast majority of patients treated with total knee arthroplasty after a previous fracture of the tibial plateau have substantial improvement in function and relief of pain. However, these patients are at increased risk for perioperative complications, as evidenced by the high reoperation rate of 21% in this study.

  18. [Application of tibial mechanical axis locator in tibial extra-articular deformity in total knee arthroplasty].

    PubMed

    Li, Guoliang; Han, Guangpu; Zhang, Jinxiu; Ma, Shiqiang; Guo, Donghui; Yuan, Fulu; Qi, Bingbing; Shen, Runbin

    2013-07-01

    To explore the application value of self-made tibial mechanical axis locator in tibial extra-articular deformity in total knee arthroplasty (TKA) for improving the lower extremity force line. Between January and August 2012, 13 cases (21 knees) of osteoarthritis with tibial extra-articular deformity were treated, including 5 males (8 knees) and 8 females (13 knees) with an average age of 66.5 years (range, 58-78 years). The disease duration was 2-5 years (mean, 3.5 years). The knee society score (KSS) was 45.5 +/- 15.5. Extra-articular deformities included 1 case of knee valgus (2 knees) and 12 cases of knee varus (19 knees). Preoperative full-length X-ray films of lower extremities showed 10-21 degrees valgus or varus deformity of tibial extra joint. Self-made tibial mechanical axis locator was used to determine and mark coronal tibial mechanical axis under X-ray before TKA, and then osteotomy was performed with extramedullary positioning device according to the mechanical axis marker.' All incisions healed by first intention, without related complications of infection and joint instability. All patients were followed up 5-12 months (mean, 8.3 months). The X-ray examination showed < 2 degrees knee deviation angle in the others except 1 case of 2.9 degrees knee deviation angle at 3 days after operation, and the accurate rate was 95.2%. No loosening or instability of prosthesis occurred during follow-up. KSS score was 85.5 +/- 15.0 at last follow-up, showing significant difference when compared with preoperative score (t=12.82, P=0.00). The seft-made tibial mechanical axis locator can improve the accurate rate of the lower extremity force line in TKA for tibia extra-articular deformity.

  19. Maximizing tibial coverage is detrimental to proper rotational alignment.

    PubMed

    Martin, Stacey; Saurez, Alex; Ismaily, Sabir; Ashfaq, Kashif; Noble, Philip; Incavo, Stephen J

    2014-01-01

    Traditionally, the placement of the tibial component in total knee arthroplasty (TKA) has focused on maximizing coverage of the tibial surface. However, the degree to which maximal coverage affects correct rotational placement of symmetric and asymmetric tibial components has not been well defined and might represent an implant design issue worthy of further inquiry. Using four commercially available tibial components (two symmetric, two asymmetric), we sought to determine (1) the overall amount of malrotation that would occur if components were placed for maximal tibial coverage; and (2) whether the asymmetric designs would result in less malrotation than the symmetric designs when placed for maximal coverage in a computer model using CT reconstructions. CT reconstructions of 30 tibial specimens were used to generate three-dimensional tibia reconstructions with attention to the tibial anatomic axis, the tibial tubercle, and the resected tibial surface. Using strict criteria, four commercially available tibial designs (two symmetric, two asymmetric) were placed on the resected tibial surface. The resulting component rotation was examined. Among all four designs, 70% of all tibial components placed in orientation maximizing fit to resection surface were internally malrotated (average 9°). The asymmetric designs had fewer cases of malrotation (28% and 52% for the two asymmetric designs, 100% and 96% for the two symmetric designs; p < 0.001) and less malrotation on average (2° and 5° for the asymmetric designs, 14° for both symmetric designs; p < 0.001). Maximizing tibial coverage resulted in implant malrotation in a large percentage of cases. Given similar amounts of tibial coverage, correct rotational positioning was more likely to occur with the asymmetric designs. Malrotation of components is an important cause of failure in TKA. Priority should be given to correct tibial rotational positioning. This study suggested that it is easier to balance rotation and

  20. Posterior tibial slope in medial opening-wedge high tibial osteotomy: 2-D versus 3-D navigation.

    PubMed

    Yim, Ji Hyeon; Seon, Jong Keun; Song, Eun Kyoo

    2012-10-01

    Although opening-wedge high tibial osteotomy (HTO) is used to correct deformities, it can simultaneously alter tibial slope in the sagittal plane because of the triangular configuration of the proximal tibia, and this undesired change in tibial slope can influence knee kinematics, stability, and joint contact pressure. Therefore, medial opening-wedge HTO is a technically demanding procedure despite the use of 2-dimensional (2-D) navigation. The authors evaluated the posterior tibial slope pre- and postoperatively in patients who underwent navigation-assisted opening-wedge HTO and compared posterior slope changes for 2-D and 3-dimensional (3-D) navigation versions. Patients were randomly divided into 2 groups based on the navigation system used: group A (2-D guidance for coronal alignment; 17 patients) and group B (3-D guidance for coronal and sagittal alignments; 17 patients). Postoperatively, the mechanical axis was corrected to a mean valgus of 2.81° (range, 1°-5.4°) in group A and 3.15° (range, 1.5°-5.6°) in group B. A significant intergroup difference existed for the amount of posterior tibial slope change (Δ slope) pre- and postoperatively (P=.04).Opening-wedge HTO using navigation offers accurate alignment of the lower limb. In particular, the use of 3-D navigation results in significantly less change in the posterior tibial slope postoperatively than does the use of 2-D navigation. Accordingly, the authors recommend the use of 3-D navigation systems because they provide real-time intraoperative information about coronal, sagittal, and transverse axes and guide the maintenance of the native posterior tibial slope. Copyright 2012, SLACK Incorporated.

  1. Role of the fibula in the stability of diaphyseal tibial fractures fixed by intramedullary nailing.

    PubMed

    Galbraith, John G; Daly, Charles J; Harty, James A; Dailey, Hannah L

    2016-10-01

    For tibial fractures, the decision to fix a concomitant fibular fracture is undertaken on a case-by-case basis. To aid in this clinical decision-making process, we investigated whether loss of integrity of the fibula significantly destabilises midshaft tibial fractures, whether fixation of the fibula restores stability to the tibia, and whether removal of the fibula and interosseous membrane for expediency in biomechanical testing significantly influences tibial interfragmentary mechanics. Tibia/fibula pairs were harvested from six cadaveric donors with the interosseous membrane intact. A tibial osteotomy fracture was fixed by reamed intramedullary (IM) nailing. Axial, torsion, bending, and shear tests were completed for four models of fibular involvement: intact fibula, osteotomy fracture, fibular plating, and resected fibula and interosseous membrane. Overall construct stiffness decreased slightly with fibular osteotomy compared to intact bone, but this change was not statistically significant. Under low loads, the influence of the fibula on construct stability was only statistically significant in torsion (large effect size). Fibular plating stiffened the construct slightly, but this change was not statistically significant compared to the fibular osteotomy case. Complete resection of the fibula and interosseous membrane significantly decreased construct torsional stiffness only (large effect size). These results suggest that fixation of the fibula may not contribute significantly to the stability of diaphyseal tibial fractures and should not be undertaken unless otherwise clinically indicated. For testing purposes, load-sharing through the interosseous membrane contributes significantly to overall construct mechanics, especially in torsion, and we recommend preservation of these structures when possible. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Tibial coverage, meniscus position, size and damage in knees discordant for joint space narrowing – data from the Osteoarthritis Initiative

    PubMed Central

    Bloecker, K.; Guermazi, A.; Wirth, W.; Benichou, O.; Kwoh, C.K.; Hunter, D.J.; Englund, M.; Resch, H.; Eckstein, F.

    2013-01-01

    SUMMARY Introduction Meniscal extrusion is thought to be associated with less meniscus coverage of the tibial surface, but the association of radiographic disease stage with quantitative measures of tibial plateau coverage is unknown. We therefore compared quantitative and semi-quantitative measures of meniscus position and morphology in individuals with bilateral painful knees discordant on medial joint space narrowing (mJSN). Methods A sample of 60 participants from the first half (2,678 cases) of the Osteoarthritis Initiative cohort fulfilled the inclusion criteria: bilateral frequent pain, Osteoarthritis Research Society International (OARSI) mJSN grades 1–3 in one, no-JSN in the contra-lateral (CL), and no lateral JSN in either knee (43 unilateral mJSN1; 17 mJSN2/3; 22 men, 38 women, body mass index (BMI) 31.3 ± 3.9 kg/m2). Segmentation and three-dimensional quantitative analysis of the tibial plateau and meniscus, and semi-quantitative evaluation of meniscus damage (magnetic resonance imaging (MRI) osteoarthritis knee score – MOAKS) was performed using coronal 3T MR images (MPR DESSwe and intermediate-weighted turbo spin echo (IW-TSE) images). CL knees were compared using paired t-tests (between-knee, within-person design). Results Medial tibial plateau coverage was 36 ± 9% in mJSN1 vs 45 ± 8% in CL no-JSN knees, and was 31 ± 9% in mJSN2/3 vs 46 ± 6% in no-JSN knees (both P < 0.001). mJSN knees showed greater meniscus extrusion and damage (MOAKS), but no significant difference in meniscus volume. No significant differences in lateral tibial coverage, lateral meniscus morphology or position were observed. Conclusions Knees with medial JSN showed substantially less medial tibial plateau coverage by the meniscus. We suggest that the less meniscal coverage, i.e., less mechanical protection may be a reason for greater rates of cartilage loss observed in JSN knees. PMID:23220556

  3. Incidence and epidemiology of tibial shaft fractures.

    PubMed

    Larsen, Peter; Elsoe, Rasmus; Hansen, Sandra Hope; Graven-Nielsen, Thomas; Laessoe, Uffe; Rasmussen, Sten

    2015-04-01

    The literature lacks recent population-based epidemiology studies of the incidence, trauma mechanism and fracture classification of tibial shaft fractures. The purpose of this study was to provide up-to-date information on the incidence of tibial shaft fractures in a large and complete population and report the distribution of fracture classification, trauma mechanism and patient baseline demographics. Retrospective reviews of clinical and radiological records. A total of 196 patients were treated for 198 tibial shaft fractures in the years 2009 and 2010. The mean age at time of fracture was 38.5 (21.2SD) years. The incidence of tibial shaft fracture was 16.9/100,000/year. Males have the highest incidence of 21.5/100,000/year and present with the highest frequency between the age of 10 and 20, whereas women have a frequency of 12.3/100,000/year and have the highest frequency between the age of 30 and 40. AO-type 42-A1 was the most common fracture type, representing 34% of all tibial shaft fractures. The majority of tibial shaft fractures occur during walking, indoor activity and sports. The distribution among genders shows that males present a higher frequency of fractures while participating in sports activities and walking. Women present the highest frequency of fractures while walking and during indoor activities. This study shows an incidence of 16.9/100,000/year for tibial shaft fractures. AO-type 42-A1 was the most common fracture type, representing 34% of all tibial shaft fractures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. System-size convergence of point defect properties: The case of the silicon vacancy

    NASA Astrophysics Data System (ADS)

    Corsetti, Fabiano; Mostofi, Arash A.

    2011-07-01

    We present a comprehensive study of the vacancy in bulk silicon in all its charge states from 2+ to 2-, using a supercell approach within plane-wave density-functional theory, and systematically quantify the various contributions to the well-known finite size errors associated with calculating formation energies and stable charge state transition levels of isolated defects with periodic boundary conditions. Furthermore, we find that transition levels converge faster with respect to supercell size when only the Γ-point is sampled in the Brillouin zone, as opposed to a dense k-point sampling. This arises from the fact that defect level at the Γ-point quickly converges to a fixed value which correctly describes the bonding at the defect center. Our calculated transition levels with 1000-atom supercells and Γ-point only sampling are in good agreement with available experimental results. We also demonstrate two simple and accurate approaches for calculating the valence band offsets that are required for computing formation energies of charged defects, one based on a potential averaging scheme and the other using maximally-localized Wannier functions (MLWFs). Finally, we show that MLWFs provide a clear description of the nature of the electronic bonding at the defect center that verifies the canonical Watkins model.

  5. Increased revision rate with posterior tibial tunnel placement after using the 70-degree tibial guide in ACL reconstruction.

    PubMed

    Inderhaug, Eivind; Raknes, Sveinung; Østvold, Thomas; Solheim, Eirik; Strand, Torbjørn

    2017-01-01

    To map knee morphology radiographically in a population with a torn ACL and to investigate whether anatomic factors could be related to outcomes after ACL reconstruction at mid- to long-term follow-up. Further, we wanted to assess tibial tunnel placement after using the 70-degree "anti-impingement" tibial tunnel guide and investigate any relation between tunnel placement and revision surgery. Patients undergoing ACL reconstruction involving the 70-degree tibial guide from 2003 to 2008 were included. Two independent investigators analysed pre- and post-operative radiographs. Demographic data and information on revision surgery were collected from an internal database. Anatomic factors and post-operative tibial tunnel placements were investigated as predictors of revision. Three-hundred and seventy-seven patients were included in the study. A large anatomic variation with significant differences between men and women was seen. None of the anatomic factors could be related to a significant increase in revision rate. Patients with a posterior tibial tunnel placement, defined as 50 % or more posterior on the Amis and Jakob line, did, however, have a higher risk of revision surgery compared to patients with an anterior tunnel placement (P = 0.03). Use of the 70-degree tibial guide did result in a high incidence (47 %) of posterior tibial tunnel placements associated with an increased rate of revision surgery. The current study was, however, not able to identify any anatomic variation that could be related to a higher risk of revision surgery. Avoiding graft impingement from the femoral roof in anterior tibial tunnel placements is important, but the insight that overly posterior tunnel placement can lead to inferior outcome should also be kept in mind when performing ACL surgery. IV.

  6. Fractures of the Tibial Plateau Involve Similar Energies as the Tibial Pilon but Greater Articular Surface Involvement

    PubMed Central

    Dibbern, Kevin; Kempton, Laurence B.; Higgins, Thomas F.; Morshed, Saam; McKinley, Todd O.; Marsh, J. Lawrence; Anderson, Donald D.

    2016-01-01

    Patients with tibial pilon fractures have a higher incidence of post-traumatic osteoarthritis than those with fractures of the tibial plateau. This may indicate that pilon fractures present a greater mechanical insult to the joint than do plateau fractures. We tested the hypothesis that fracture energy and articular fracture edge length, two independent indicators of severity, are higher in pilon than plateau fractures. We also evaluated if clinical fracture classification systems accurately reflect severity. Seventy-five tibial plateau fractures and fifty-two tibial pilon fractures from a multi-institutional study were selected to span the spectrum of severity. Fracture severity measures were calculated using objective CT-based image analysis methods. The ranges of fracture energies measured for tibial plateau and pilon fractures were 3.2 to 33.2 Joules (J) and 3.6 to 32.2 J, respectively, and articular fracture edge lengths were 68.0 to 493.0 mm and 56.1 to 288.6 mm, respectively. There were no differences in the fracture energies between the two fracture types, but plateau fractures had greater articular fracture edge lengths (p<0.001). The clinical fracture classifications generally reflected severity, but there was substantial overlap of fracture severity measures between different classes. Clinical Significance Similar fracture energies with different degrees of articular surface involvement suggest a possible explanation for dissimilar rates of post-traumatic osteoarthritis for fractures of the tibial plateau compared to the tibial pilon. The substantial overlap of severity measures between different fracture classes may well have confounded prior clinical studies relying on fracture classification as a surrogate for severity. PMID:27381653

  7. Trifurcation of the tibial nerve within the tarsal tunnel.

    PubMed

    Develi, Sedat

    2018-05-01

    The tibial nerve is the larger terminal branch of the sciatic nerve and it terminates in the tarsal tunnel by giving lateral and medial plantar nerves. We present a rare case of trifurcation of the tibial nerve within the tarsal tunnel. The variant nerve curves laterally after branching from the tibial nerve and courses deep to quadratus plantae muscle. Interestingly, posterior tibial artery was also terminating by giving three branches. These branches were accompanying the terminal branches of the tibial nerve.

  8. Importance of elastic finite-size effects: Neutral defects in ionic compounds

    DOE PAGES

    Burr, P. A.; Cooper, M. W. D.

    2017-09-15

    Small system sizes are a well known source of error in DFT calculations, yet computational constraints frequently dictate the use of small supercells, often as small as 96 atoms in oxides and compound semiconductors. In ionic compounds, electrostatic finite size effects have been well characterised, but self-interaction of charge neutral defects is often discounted or assumed to follow an asymptotic behaviour and thus easily corrected with linear elastic theory. Here we show that elastic effect are also important in the description of defects in ionic compounds and can lead to qualitatively incorrect conclusions if inadequatly small supercells are used; moreover,more » the spurious self-interaction does not follow the behaviour predicted by linear elastic theory. Considering the exemplar cases of metal oxides with fluorite structure, we show that numerous previous studies, employing 96-atom supercells, misidentify the ground state structure of (charge neutral) Schottky defects. We show that the error is eliminated by employing larger cells (324, 768 and 1500 atoms), and careful analysis determines that elastic effects, not electrostatic, are responsible. The spurious self-interaction was also observed in non-oxide ionic compounds and irrespective of the computational method used, thereby resolving long standing discrepancies between DFT and force-field methods, previously attributed to the level of theory. The surprising magnitude of the elastic effects are a cautionary tale for defect calculations in ionic materials, particularly when employing computationally expensive methods (e.g. hybrid functionals) or when modelling large defect clusters. We propose two computationally practicable methods to test the magnitude of the elastic self-interaction in any ionic system. In commonly studies oxides, where electrostatic effects would be expected to be dominant, it is the elastic effects that dictate the need for larger supercells | greater than 96 atoms.« less

  9. Importance of elastic finite-size effects: Neutral defects in ionic compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burr, P. A.; Cooper, M. W. D.

    Small system sizes are a well known source of error in DFT calculations, yet computational constraints frequently dictate the use of small supercells, often as small as 96 atoms in oxides and compound semiconductors. In ionic compounds, electrostatic finite size effects have been well characterised, but self-interaction of charge neutral defects is often discounted or assumed to follow an asymptotic behaviour and thus easily corrected with linear elastic theory. Here we show that elastic effect are also important in the description of defects in ionic compounds and can lead to qualitatively incorrect conclusions if inadequatly small supercells are used; moreover,more » the spurious self-interaction does not follow the behaviour predicted by linear elastic theory. Considering the exemplar cases of metal oxides with fluorite structure, we show that numerous previous studies, employing 96-atom supercells, misidentify the ground state structure of (charge neutral) Schottky defects. We show that the error is eliminated by employing larger cells (324, 768 and 1500 atoms), and careful analysis determines that elastic effects, not electrostatic, are responsible. The spurious self-interaction was also observed in non-oxide ionic compounds and irrespective of the computational method used, thereby resolving long standing discrepancies between DFT and force-field methods, previously attributed to the level of theory. The surprising magnitude of the elastic effects are a cautionary tale for defect calculations in ionic materials, particularly when employing computationally expensive methods (e.g. hybrid functionals) or when modelling large defect clusters. We propose two computationally practicable methods to test the magnitude of the elastic self-interaction in any ionic system. In commonly studies oxides, where electrostatic effects would be expected to be dominant, it is the elastic effects that dictate the need for larger supercells | greater than 96 atoms.« less

  10. Importance of elastic finite-size effects: Neutral defects in ionic compounds

    NASA Astrophysics Data System (ADS)

    Burr, P. A.; Cooper, M. W. D.

    2017-09-01

    Small system sizes are a well-known source of error in density functional theory (DFT) calculations, yet computational constraints frequently dictate the use of small supercells, often as small as 96 atoms in oxides and compound semiconductors. In ionic compounds, electrostatic finite-size effects have been well characterized, but self-interaction of charge-neutral defects is often discounted or assumed to follow an asymptotic behavior and thus easily corrected with linear elastic theory. Here we show that elastic effects are also important in the description of defects in ionic compounds and can lead to qualitatively incorrect conclusions if inadequately small supercells are used; moreover, the spurious self-interaction does not follow the behavior predicted by linear elastic theory. Considering the exemplar cases of metal oxides with fluorite structure, we show that numerous previous studies, employing 96-atom supercells, misidentify the ground-state structure of (charge-neutral) Schottky defects. We show that the error is eliminated by employing larger cells (324, 768, and 1500 atoms), and careful analysis determines that elastic, not electrostatic, effects are responsible. The spurious self-interaction was also observed in nonoxide ionic compounds irrespective of the computational method used, thereby resolving long-standing discrepancies between DFT and force-field methods, previously attributed to the level of theory. The surprising magnitude of the elastic effects is a cautionary tale for defect calculations in ionic materials, particularly when employing computationally expensive methods (e.g., hybrid functionals) or when modeling large defect clusters. We propose two computationally practicable methods to test the magnitude of the elastic self-interaction in any ionic system. In commonly studied oxides, where electrostatic effects would be expected to be dominant, it is the elastic effects that dictate the need for larger supercells: greater than 96 atoms.

  11. Histological analysis of the tibial anterior cruciate ligament insertion.

    PubMed

    Oka, Shinya; Schuhmacher, Peter; Brehmer, Axel; Traut, Ulrike; Kirsch, Joachim; Siebold, Rainer

    2016-03-01

    This study was performed to investigate the morphology of the tibial anterior cruciate ligament (ACL) by histological assessment. The native (undissected) tibial ACL insertion of six fresh-frozen cadaveric knees was cut into four sagittal sections parallel to the long axis of the medial tibial spine. For histological evaluation, the slices were stained with haematoxylin and eosin, Safranin O and Russell-Movat pentachrome. All slices were digitalized and analysed at a magnification of 20×. The anterior tibial ACL insertion was bordered by a bony anterior ridge. The most medial ACL fibres inserted from the medial tibial spine and were adjacent to the articular cartilage of the medial tibial plateau. Parts of the bony insertions of the anterior and posterior horns of the lateral meniscus were in close contact with the lateral part of the tibial ACL insertion. A small fat pad was located just posterior to the functional ACL fibres. The anterior-posterior length of the medial ACL insertion was an average of 10.8 ± 1.1 mm compared with the lateral, which was only 6.2 ± 1.1 mm (p < 0.001). There were no central or posterolateral inserting ACL fibres. The shape of the bony tibial ACL insertion was 'duck-foot-like'. In contrast to previous findings, the functional mid-substance fibres arose from the most posterior part of the 'duck-foot' in a flat and 'c-shaped' way. The most anterior part of the tibial ACL insertion was bordered by a bony anterior ridge and the most medial by the medial tibial spine. No posterolateral fibres nor ACL bundles have been found histologically. This histological investigation may improve our understanding of the tibial ACL insertion and may provide important information for anatomical ACL reconstruction.

  12. High altitude hypoxia as a factor that promotes tibial growth plate development in broiler chickens

    PubMed Central

    Huang, Shucheng; Zhang, Lihong; Rehman, Mujeeb Ur; Iqbal, Muhammad Kashif; Lan, Yanfang; Mehmood, Khalid; Zhang, Hui; Qiu, Gang; Nabi, Fazul; Yao, Wangyuan; Wang, Meng; Li, Jiakui

    2017-01-01

    Tibial dyschondroplasia (TD) is one of the most common problems in the poultry industry and leads to lameness by affecting the proximal growth plate of the tibia. However, due to the unique environmental and geographical conditions of Tibet, no case of TD has been reported in Tibetan chickens (TBCs). The present study was designed to investigate the effect of high altitude hypoxia on blood parameters and tibial growth plate development in chickens using the complete blood count, morphology, and histological examination. The results of this study showed an undesirable impact on the overall performance, body weight, and mortality of Arbor Acres chickens (AACs) exposed to a high altitude hypoxic environment. However, AACs raised under hypoxic conditions showed an elevated number of red blood cells (RBCs) and an increase in hemoglobin and hematocrit values on day 14 compared to the hypobaric normoxia group. Notably, the morphology and histology analyses showed that the size of tibial growth plates in AACs was enlarged and that the blood vessel density was also higher after exposure to the hypoxic environment for 14 days, while no such change was observed in TBCs. Altogether, our results revealed that the hypoxic environment has a potentially new role in increasing the blood vessel density of proximal tibial growth plates to strengthen and enhance the size of the growth plates, which may provide new insights for the therapeutic manipulation of hypoxia in poultry TD. PMID:28282429

  13. Characterization of micron-sized, optical coating defects by photothermal deflection microscopy

    NASA Astrophysics Data System (ADS)

    Abate, J. A.; Schmid, A. W.; Guardalben, M. G.; Smith, D. J.; Jacobs, S. D.

    1984-04-01

    Information about the localized absorbing defects in optical thin films is required for a better understanding of laser induced damage. Photothermal deflection microscopy offers a nondestructive optical diagnostic which yields spatially resolved absorption data on simple and multiple layer AR and HR dielectric coatings. The computer controlled apparatus used to generate absorption maps of dielectric thin films and an experiment in which a partial correlation between localized absorption sites and damage caused by nanosecond laser irradiation at 351 nm is established are described. An absolute calibration of absorption for our measurement technique is presented here. Micron sized absorbtive defects of Cu were introduced into our coatings to provide a means of calibration. Also presented here are some preliminary data on the modification of the absorption signatures measured by photothermal deflection as a function of the location of the defect within the coating layers.

  14. Do modern total knee replacements improve tibial coverage?

    PubMed

    Meier, Malin; Webb, Jonathan; Collins, Jamie E; Beckmann, Johannes; Fitz, Wolfgang

    2018-01-25

    The purpose of the present study is to compare newer designs of various symmetric and asymmetric tibial components and measure tibial bone coverage using the rotational safe zone defined by two commonly utilized anatomic rotational landmarks. Computed tomography scans (CT scans) of one hundred consecutive patients scheduled for total knee arthroplasty were obtained pre-operatively. A virtual proximal tibial cut was performed and two commonly used rotational axes were added for each image: the medio-lateral axis (ML-axis) and the medial 1/3 tibial tubercle axis (med-1/3-axis). Different symmetric and asymmetric implant designs were then superimposed in various rotational positions for best cancellous and cortical coverage. The images were imported to a public domain imaging software, and cancellous and cortical bone coverage was computed for each image, with each implant design in various rotational positions. One single implant type could not be identified that provided the best cortical and cancellous coverage of the tibia, irrespective of using the med-1/3-axis or the ML-axis for rotational alignment. However, it could be confirmed that the best bone coverage was dependent on the selected rotational landmark. Furthermore, improved bone coverage was observed when tibial implant positions were optimized between the two rotational axes. Tibial coverage is similar for symmetric and asymmetric designs, but depends on the rotational landmark for which the implant is designed. The surgeon has the option to improve tibial coverage by optimizing placement between the two anatomic rotational alignment landmarks, the medial 1/3 and the ML-axis. Surgeons should be careful assessing intraoperative rotational tibial placement using the described anatomic rotational landmarks to optimize tibial bony coverage without compromising patella tracking. III.

  15. Preserving the PCL during the tibial cut in total knee arthroplasty.

    PubMed

    Cinotti, G; Sessa, P; Amato, M; Ripani, F R; Giannicola, G

    2017-08-01

    Previous studies have shown that the PCL insertion may be damaged during the tibial cut performed in total knee arthroplasty. We investigated the maximum thickness of a tibial cut that preserves the PCL insertion and to what extent the posterior slope of the tibial cut and that of the patient's tibial plateaus affect the outcome. MR images of 83 knees were analysed. The maximum thickness of a tibial cut that preserves the PCL using a posterior slope of 0°, 3°, 5° and parallel to the patient's slope of the tibial plateau, was evaluated. Correlations between the results and the degrees of the posterior slope of the patient's tibial plateaus were also investigated. The maximum thickness of a tibial cut that preserves the entire PCL insertion was, on average, 5.5, 4.7, 4.2 and 3.1 mm when a posterior slope of 0°, 3°, 5° and parallel to the patients' tibial plateaus was used, respectively. When the 25th percentile was considered, the maximum thickness of a tibial cut that preserved the PCL was 4 and 3 mm with a tibial cut of 0° and 5° of posterior slope, respectively. The maximum thickness of a tibial cut that preserved the PCL was significantly greater in patients with a sagittal slope of the tibial plateaus more than 8° than in those with a sagittal slope less than 8°. In cruciate retaining implants, the PCL insertion may be spared in the majority of patients by performing a tibial cut of 4 mm, or even less when a posterior slope of 3°-5° is used. The clinical relevance of our study is that the execution of a conservative tibial cut, followed by a second tibial resection to achieve the thickness required for the tibial component to be implanted, may be an alternative technique to spare the PCL in CR TKA. II.

  16. Reliable critical sized defect rodent model for cleft palate research.

    PubMed

    Mostafa, Nesrine Z; Doschak, Michael R; Major, Paul W; Talwar, Reena

    2014-12-01

    Suitable animal models are necessary to test the efficacy of new bone grafting therapies in cleft palate surgery. Rodent models of cleft palate are available but have limitations. This study compared and modified mid-palate cleft (MPC) and alveolar cleft (AC) models to determine the most reliable and reproducible model for bone grafting studies. Published MPC model (9 × 5 × 3 mm(3)) lacked sufficient information for tested rats. Our initial studies utilizing AC model (7 × 4 × 3 mm(3)) in 8 and 16 weeks old Sprague Dawley (SD) rats revealed injury to adjacent structures. After comparing anteroposterior and transverse maxillary dimensions in 16 weeks old SD and Wistar rats, virtual planning was performed to modify MPC and AC defects dimensions, taking the adjacent structures into consideration. Modified MPC (7 × 2.5 × 1 mm(3)) and AC (5 × 2.5 × 1 mm(3)) defects were employed in 16 weeks old Wistar rats and healing was monitored by micro-computed tomography and histology. Maxillary dimensions in SD and Wistar rats were not significantly different. Preoperative virtual planning enhanced postoperative surgical outcomes. Bone healing occurred at defect margin leaving central bone void confirming the critical size nature of the modified MPC and AC defects. Presented modifications for MPC and AC models created clinically relevant and reproducible defects. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  17. Bypass grafting to the anterior tibial artery.

    PubMed

    Armour, R H

    1976-01-01

    Four patients with severe ischaemia of a leg due to atherosclerotic occlusion of the tibial and peroneal arteries had reversed long saphenous vein grafts to the patent lower part of the anterior tibial artery. Two of these grafts continue to function 19 and 24 months after operation respectively. One graft failed on the fifth postoperative day and another occluded 4 months after operation. The literature on femorotibial grafting has been reviewed. The early failure rate of distal grafting is higher than in the case of femoropopliteal bypass, but a number of otherwise doomed limbs can be salvaged. Contrary to widely held views, grafting to the anterior tibial artery appears to give results comparable to those obtained when the lower anastomosis is made to the posterior tibial artery.

  18. Physeal growth arrest after tibial lengthening in achondroplasia

    PubMed Central

    2012-01-01

    Background and purpose Bilateral tibial lengthening has become one of the standard treatments for upper segment-lower segment disproportion and to improve quality of life in achondroplasia. We determined the effect of tibial lengthening on the tibial physis and compared tibial growth that occurred at the physis with that in non-operated patients with acondroplasia. Methods We performed a retrospective analysis of serial radiographs until skeletal maturity in 23 achondroplasia patients who underwent bilateral tibial lengthening before skeletal maturity (lengthening group L) and 12 achondroplasia patients of similar height and age who did not undergo tibial lengthening (control group C). The mean amount of lengthening of tibia in group L was 9.2 cm (lengthening percentage: 60%) and the mean age at the time of lengthening was 8.2 years. The mean duration of follow-up was 9.8 years. Results Skeletal maturity (fusion of physis) occurred at 15.2 years in group L and at 16.0 years in group C. The actual length of tibia (without distraction) at skeletal maturity was 238 mm in group L and 277 mm in group C (p = 0.03). The mean growth rates showed a decrease in group L relative to group C from about 2 years after surgery. Physeal closure was most pronounced on the anterolateral proximal tibial physis, with relative preservation of the distal physis. Interpretation Our findings indicate that physeal growth rate can be disturbed after tibial lengthening in achondroplasia, and a close watch should be kept for such an occurrence—especially when lengthening of more than 50% is attempted. PMID:22489887

  19. Toxicity and developmental defects of different sizes and shape nickel nanoparticles in zebrafish

    PubMed Central

    Ispas, Cristina; Andreescu, Daniel; Patel, Avni; Goia, Dan V.; Andreescu, Silvana; Wallace, Kenneth N.

    2009-01-01

    Metallic nanoparticles such as nickel are used in catalytic, sensing and electronic applications, but health and environmental affects have not been fully investigated. While some metal nanoparticles result in toxicity, it is also important to determine whether nanoparticles of the same metal but of different size and shape changes toxicity. Three different size nickel nanoparticle (Ni NPs) of 30, 60, and 100 nm and larger particle clusters of aggregated 60 nm entities with a dendritic structure were synthesized and exposed to zebrafish embryos assessing mortality and developmental defects. Ni NPs exposure was compared to soluble nickel salts. All three 30, 60, and 100 nm Ni NPs are equal to or less toxic than soluble nickel while dendritic clusters were more toxic. With each Ni NP exposure, thinning of the intestinal epithelium first occurs around the LD10 continuing into the LD50. LD50 exposure also results in skeletal muscle fiber separation. Exposure to soluble nickel does not cause intestinal defects while skeletal muscle separation occurs at concentrations well over LD50. These results suggest that configuration of nanoparticles may affect toxicity more than size and defects from Ni NPs exposure occur by different biological mechanisms than soluble nickel. PMID:19746736

  20. An Improved Tibial Force Sensor to Compute Contact Forces and Contact Locations In Vitro After Total Knee Arthroplasty.

    PubMed

    Roth, Joshua D; Howell, Stephen M; Hull, Maury L

    2017-04-01

    Contact force imbalance and contact kinematics (i.e., motion of the contact location in each compartment during flexion) of the tibiofemoral joint are both important predictors of a patient's outcome following total knee arthroplasty (TKA). Previous tibial force sensors have limitations in that they either did not determine contact forces and contact locations independently in the medial and lateral compartments or only did so within restricted areas of the tibial insert, which prevented them from thoroughly evaluating contact force imbalance and contact kinematics in vitro. Accordingly, the primary objective of this study was to present the design and verification of an improved tibial force sensor which overcomes these limitations. The improved tibial force sensor consists of a modified tibial baseplate which houses independent medial and lateral arrays of three custom tension-compression transducers each. This sensor is interchangeable with a standard tibial component because it accommodates tibial articular surface inserts with a range of sizes and thicknesses. This sensor was verified by applying known loads at known locations over the entire surface of the tibial insert to determine the errors in the computed contact force and contact location in each compartment. The root-mean-square errors (RMSEs) in contact force are ≤ 6.1 N which is 1.4% of the 450 N full-scale output. The RMSEs in contact location are ≤ 1.6 mm. This improved tibial force sensor overcomes the limitations of the previous sensors and therefore should be useful for in vitro evaluation of new alignment goals, new surgical techniques, and new component designs in TKA.

  1. In vivo investigation of tissue-engineered periosteum for the repair of allogeneic critical size bone defects in rabbits.

    PubMed

    Zhao, Lin; Zhao, Junli; Yu, Jiajia; Sun, Rui; Zhang, Xiaofeng; Hu, Shuhua

    2017-04-01

    The aim of the study was to evaluate the efficacy of tissue-engineered periosteum (TEP) in repairing allogenic bone defects in the long term. TEP was biofabricated with osteoinduced rabbit bone marrow mesenchymal stem cells and porcine small intestinal submucosa (SIS). A total of 24 critical sized defects were created bilaterally in radii of 12 New Zealand White rabbits. TEP/SIS was implanted into the defect site. Bone defect repair was evaluated with radiographic and histological examination at 4, 8 and 12 weeks. Bone defects were structurally reconstructed in the TEP group with mature cortical bone and medullary canals, however this was not observed in the SIS group at 12 weeks. The TEP approach can effectively restore allogenic critical sized defects, and achieve maturity of long-bone structure in 12 weeks in rabbit models.

  2. BMP delivery complements the guiding effect of scaffold architecture without altering bone microstructure in critical-sized long bone defects: A multiscale analysis.

    PubMed

    Cipitria, A; Wagermaier, W; Zaslansky, P; Schell, H; Reichert, J C; Fratzl, P; Hutmacher, D W; Duda, G N

    2015-09-01

    Scaffold architecture guides bone formation. However, in critical-sized long bone defects additional BMP-mediated osteogenic stimulation is needed to form clinically relevant volumes of new bone. The hierarchical structure of bone determines its mechanical properties. Yet, the micro- and nanostructure of BMP-mediated fast-forming bone has not been compared with slower regenerating bone without BMP. We investigated the combined effects of scaffold architecture (physical cue) and BMP stimulation (biological cue) on bone regeneration. It was hypothesized that a structured scaffold directs tissue organization through structural guidance and load transfer, while BMP stimulation accelerates bone formation without altering the microstructure at different length scales. BMP-loaded medical grade polycaprolactone-tricalcium phosphate scaffolds were implanted in 30mm tibial defects in sheep. BMP-mediated bone formation after 3 and 12 months was compared with slower bone formation with a scaffold alone after 12 months. A multiscale analysis based on microcomputed tomography, histology, polarized light microscopy, backscattered electron microscopy, small angle X-ray scattering and nanoindentation was used to characterize bone volume, collagen fiber orientation, mineral particle thickness and orientation, and local mechanical properties. Despite different observed kinetics in bone formation, similar structural properties on a microscopic and sub-micron level seem to emerge in both BMP-treated and scaffold only groups. The guiding effect of the scaffold architecture is illustrated through structural differences in bone across different regions. In the vicinity of the scaffold increased tissue organization is observed at 3 months. Loading along the long bone axis transferred through the scaffold defines bone micro- and nanostructure after 12 months. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. The reverse sural artery fasciomusculocutaneous flap for small lower-limb defects: the use of the gastrocnemius muscle cuff as a plug for small bony defects following debridement of infected/necrotic bone.

    PubMed

    Al-Qattan, M M

    2007-09-01

    The reverse sural artery fasciomusculocutaneous flap is a modification of the original fasciocutaneous flap in which a midline gastrocnemius muscle cuff around the buried sural pedicle is included in the flap. This modification was done to improve the blood supply of the distal part of the flap, which is harvested from the upper leg. The aim of this paper is to demonstrate that there is another important advantage of the modified flap: the use of the muscle cuff as a "plug" for small lower limb defects following debridement of infected/necrotic bone. A total of 10 male adult patients with small complex lower-limb defects with underlying bone pathology were treated with the modified flap using the muscle component to fill up the small bony defects. The bony pathology included necrotic exposed bone without evidence of osteomyelitis or wound infection (n = 1), an underlying neglected tibial fracture with wound infection (n = 4), and a sinus at the heel with underlying calcaneal osteomyelitis (n = 5). Primary wound healing of the flap into the defect was noted in all patients. No recurrence of calcaneal osteomyelitis was seen and all tibial fractures united following appropriate orthopedic fixation. It was concluded that the reverse sural artery fasciomusculocutaneous flap is well suited for small complex lower-limb defects with underlying bone pathology.

  4. Anterior Cruciate Ligament Reconstruction with Tibial Attachment Preserving Hamstring Graft without Implant on Tibial Side

    PubMed Central

    Sinha, Skand; Naik, Ananta Kumar; Maheshwari, Mridul; Sandanshiv, Sumedh; Meena, Durgashankar; Arya, Rajendra K

    2018-01-01

    Background: Tibial attachment preserving hamstring graft could prevent potential problems of free graft in anterior cruciate ligament (ACL) reconstruction such as pull out before graft-tunnel healing or rupture before ligamentization. Different implants have been reportedly used for tibial side fixation with this technique. We investigated short-term outcome of ACL reconstruction (ACLR) with tibial attachment sparing hamstring graft without implant on the tibial side by outside in technique. Materials and Methods: Seventy nine consecutive cases of ACL tear having age of 25.7 ± 6.8 years were included after Institutional Board Approval. All subjects were male. The mean time interval from injury to surgery was of 7.5 ± 6.4 months. Hamstring tendons were harvested with open tendon stripper leaving the tibial insertion intact. The free ends of the tendons were whip stitched, quadrupled, and whip stitched again over the insertion site of hamstring with fiber wire (Arthrex). Single bundle ACLR was done by outside in technique and the femoral tunnel was created with cannulated reamer. The graft was pulled up to the external aperture of femoral tunnel and fixed with interference screw (Arthrex). The scoring was done by Lysholm, Tegner, and KT 1000 by independent observers. All cases were followed up for 2 years. Results: The mean length of quadrupled graft attached to tibia was 127.65 ± 7.5 mm, and the mean width was 7.52 ± 0.78 mm. The mean preoperative Lysholm score of 47.15 ± 9.6, improved to 96.8 ± 2.4 at 1 year. All cases except two returned to the previous level of activity after ACLR. There was no significant difference statistically between preinjury (5.89 ± 0.68) and postoperative (5.87 ± 0.67) Tegner score. The anterior tibial translation (ATT) (KT 1000) improved from 11.44 ± 1.93 mm to 3.59 ± 0.89 mm. The ATT of operated knee returned to nearly the similar value as of the opposite knee (3.47 ± 1.16 mm). The Pivot shift test was negative in all cases

  5. Calcium phosphate cement augmentation in the treatment of depressed tibial plateau fractures with open reduction and internal fixation.

    PubMed

    Oztürkmen, Yusuf; Caniklioğlu, Mustafa; Karamehmetoğlu, Mahmut; Sükür, Erhan

    2010-01-01

    We aimed to evaluate the clinical and radiological outcomes of open reduction and internal fixation augmented with calcium phosphate cement (CPC) in the treatment of depressed tibial plateau fractures. Twenty-eight knees of 28 patients [19 males and 9 females; mean age, 41.2 years (range 22-72 years)] who had open reduction and internal fixation combined with CPC augmentation were included in this study. Seventeen fractures were Schatzker type II, 5 were type III, 3 were type IV, 2 were type V, and 1 was type VI. CPC was used to fill the subchondral bone defects in all knees. Fixation of the fragments was done with screws in 3 knees (10%). Standard proximal tibial plates or buttress plates were used in 25 knees (90%) with an additional split fragment extending distally to achieve internal fixation. Full weight-bearing was allowed in 6.4 weeks (range 6-12 weeks) after surgery. Resorption of CPC granules was defined as the decrease in the size and density of grafting material on radiographs. Rasmussen's radiological and clinical scores were determined postoperatively. Functionality was assessed with Lysholm knee scoring system. Activity was graded with Tegner's activity scale. Union was achieved in all patients with a mean follow-up of 22.2 months (range 6-36 months). There were no intraoperative complications. At the latest follow-up radiographs, resorption of the graft was observed in 25 knees (89%). Rasmussen's radiologic score was excellent in 17 patients (61%), good in 9 patients (32%), and fair in 2 patients (7%). Rasmussen's clinical score was excellent in 9 patients (32%), good in 18 patients (64%), and fair in 1 patient (4%). According to the Lysholm knee score, functional results were excellent in 16 patients (57%), good in 8 patients (29%), and fair in 4 patients (14%). Twenty-two patients (78%) achieved the preoperative activity level after surgery, and there was no significant difference between the mean preoperative and postoperative Tegner scores (4

  6. Effects of Socket Size on Metrics of Socket Fit in Trans-Tibial Prosthesis Users

    PubMed Central

    Sanders, Joan E; Youngblood, Robert T; Hafner, Brian J; Cagle, John C; McLean, Jake B; Redd, Christian B; Dietrich, Colin R; Ciol, Marcia A; Allyn, Katheryn J

    2017-01-01

    The purpose of this research was to conduct a preliminary effort to identify quantitative metrics to distinguish a good socket from an oversized socket in people with trans-tibial amputation. Results could be used to inform clinical practices related to socket replacement. A cross-over study was conducted on community ambulators (K-level 3 or 4) with good residual limb sensation. Participants were each provided with two sockets, a duplicate of their as-prescribed socket and a modified socket that was enlarged or reduced by 1.8 mm (~6% of the socket volume) based on the fit quality of the as-prescribed socket. The two sockets were termed a larger socket and a smaller socket. Activity was monitored while participants wore each socket for 4wk. Participants’ gait; self-reported satisfaction, quality of fit, and performance; socket comfort; and morning-to-afternoon limb fluid volume changes were assessed. Visual analysis of plots and estimated effect sizes (measure as mean difference divided by standard deviation) showed largest effects for step time asymmetry, step width asymmetry, anterior and anterior-distal morning-to-afternoon fluid volume change, socket comfort scores, and self-reported measures of utility, satisfaction, and residual limb health. These variables may be viable metrics for early detection of deterioration in socket fit, and should be tested in a larger clinical study. PMID:28373013

  7. Effects of socket size on metrics of socket fit in trans-tibial prosthesis users.

    PubMed

    Sanders, Joan E; Youngblood, Robert T; Hafner, Brian J; Cagle, John C; McLean, Jake B; Redd, Christian B; Dietrich, Colin R; Ciol, Marcia A; Allyn, Katheryn J

    2017-06-01

    The purpose of this research was to conduct a preliminary effort to identify quantitative metrics to distinguish a good socket from an oversized socket in people with trans-tibial amputation. Results could be used to inform clinical practices related to socket replacement. A cross-over study was conducted on community ambulators (K-level 3 or 4) with good residual limb sensation. Participants were each provided with two sockets, a duplicate of their as-prescribed socket and a modified socket that was enlarged or reduced by 1.8mm (∼6% of the socket volume) based on the fit quality of the as-prescribed socket. The two sockets were termed a larger socket and a smaller socket. Activity was monitored while participants wore each socket for 4 weeks. Participants' gait; self-reported satisfaction, quality of fit, and performance; socket comfort; and morning-to-afternoon limb fluid volume changes were assessed. Visual analysis of plots and estimated effect sizes (measured as mean difference divided by standard deviation) showed largest effects for step time asymmetry, step width asymmetry, anterior and anterior-distal morning-to-afternoon fluid volume change, socket comfort score, and self-reported utility. These variables may be viable metrics for early detection of deterioration in socket fit, and should be tested in a larger clinical study. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  8. All-polyethylene tibial components in distal femur limb-salvage surgery: a finite element analysis based on promising clinical outcomes.

    PubMed

    Tang, Fan; Zhou, Yong; Zhang, Wenli; Min, Li; Shi, Rui; Luo, Yi; Duan, Hong; Tu, Chongqi

    2017-04-04

    Whether all-polyethylene tibial (APT) components are beneficial to patients who received distal femur limb-salvage surgery lacks high-quality clinical follow-up and mechanical evidence. This study aimed to investigate the biomechanics of the distal femur reconstructed with APT tumor knee prostheses using finite element (FE) analysis based on our previous, promising clinical outcome. Three-dimensional FE models that use APT and metal-backed tibial (MBT) prostheses to reconstruct distal femoral bone defects were developed and input into the Abaqus FEA software version 6.10.1. Mesh refinement tests and gait simulation with a single foot both in the upright and 15°-flexion positions with mechanical loading were conducted. Stress distribution analysis was compared between APT and MBT at the two static positions. For both prosthesis types, the stress was concentrated on the junction of the stem and shaft, and the maximum stress in the femoral axis base was more than 100 Mpa. The stress on the tibial surface was relatively distributed, which was 1-19 MPa. The stress on the tibial bone-cement layer of the APT prosthesis was approximately 20 times higher than that on the MBT prosthesis in the same region. The stress on the proximal tibial cancellous bone and cortical bone of the APT prosthesis was 3-5 times greater than that of the MBT prosthesis, and it was more distributed. Although the stress of bone-cement around the APT component is relatively high, the stress was better distributed at the polyethylene-cement-bone interface in APT than in MBT prosthesis, which effectively protects the proximal tibia in distal femur tumor knee prosthesis replacement. These results should be considered when selecting the appropriate tibial component for a patient, especially under the foreseeable conditions of osteoporosis.

  9. Bilateral double level tibial lengthening in dwarfism.

    PubMed

    Burghardt, Rolf D; Yoshino, Koichi; Kashiwagi, Naoya; Yoshino, Shigeo; Bhave, Anil; Paley, Dror; Herzenberg, John E

    2015-12-01

    Outcome assessment after double level tibial lengthening in patients with dwarfism. Fourteen patients with dwarfism were analyzed after bilateral simultaneous double level tibial lengthening. Average age was 15.1 years. Average lengthening was 13.5 cm. The two levels were lengthened by an average of 7.5 cm proximally and 6.0 cm distally. Concomitant deformities were also addressed during lengthening. External fixation treatment time averaged 8.8 months. Healing index averaged 0.7 months/cm. Bilateral tibial lengthening for dwarfism is difficult, but the results are usually quite gratifying.

  10. Minimizing Alteration of Posterior Tibial Slope During Opening Wedge High Tibial Osteotomy: a Protocol with Experimental Validation in Paired Cadaveric Knees

    PubMed Central

    Westermann, Robert W; DeBerardino, Thomas; Amendola, Annunziato

    2014-01-01

    Introduction The High Tibial Osteotomy (HTO) is a reliable procedure in addressing uni- compartmental arthritis with associated coronal deformities. With osteotomy of the proximal tibia, there is a risk of altering the tibial slope in the sagittal plane. Surgical techniques continue to evolve with trends towards procedure reproducibility and simplification. We evaluated a modification of the Arthrex iBalance technique in 18 paired cadaveric knees with the goals of maintaining sagittal slope, increasing procedure efficiency, and decreasing use of intraoperative fluoroscopy. Methods Nine paired cadaveric knees (18 legs) underwent iBalance medial opening wedge high tibial osteotomies. In each pair, the right knee underwent an HTO using the modified technique, while all left knees underwent the traditional technique. Independent observers evaluated postoperative factors including tibial slope, placement of hinge pin, and implant placement. Specimens were then dissected to evaluate for any gross muscle, nerve or vessel injury. Results Changes to posterior tibial slope were similar using each technique. The change in slope in traditional iBalance technique was -0.3° ±2.3° and change in tibial slope using the modified iBalance technique was -0.4° ±2.3° (p=0.29). Furthermore, we detected no differences in posterior tibial slope between preoperative and postoperative specimens (p=0.74 traditional, p=0.75 modified). No differences in implant placement were detected between traditional and modified techniques. (p=0.85). No intraoperative iatrogenic complications (i.e. lateral cortex fracture, blood vessel or nerve injury) were observed in either group after gross dissection. Discussion & Conclusions Alterations in posterior tibial slope are associated with HTOs. Both traditional and modified iBalance techniques appear reliable in coronal plane corrections without changing posterior tibial slope. The present modification of the Arthrex iBalance technique may increase the

  11. Proximal tibial osteotomy. A survivorship analysis.

    PubMed

    Ritter, M A; Fechtman, R A

    1988-01-01

    Proximal tibial osteotomy is generally accepted as a treatment for the patient with unicompartmental arthritis. However, a few reports of the long-term results of this procedure are available in the literature, and none have used the technique known as survivorship analysis. This technique has an advantage over conventional analysis because it does not exclude patients for inadequate follow-up, loss to follow-up, or patient death. In this study, survivorship analysis was applied to 78 proximal tibial osteotomies, performed exclusively by the senior author for the correction of a preoperative varus deformity, and a survival curve was constructed. It was concluded that the reliable longevity of the proximal tibial osteotomy is approximately 6 years.

  12. Compartment syndrome after tibial plateau fracture☆

    PubMed Central

    Pitta, Guilherme Benjamin Brandão; dos Santos, Thays Fernanda Avelino; dos Santos, Fernanda Thaysa Avelino; da Costa Filho, Edelson Moreira

    2014-01-01

    Fractures of the tibial plateau are relatively rare, representing around 1.2% of all fractures. The tibia, due to its subcutaneous location and poor muscle coverage, is exposed and suffers large numbers of traumas, not only fractures, but also crush injuries and severe bruising, among others, which at any given moment, could lead compartment syndrome in the patient. The case is reported of a 58-year-old patient who, following a tibial plateau fracture, presented compartment syndrome of the leg and was submitted to decompressive fasciotomy of the four right compartments. After osteosynthesis with internal fixation of the tibial plateau using an L-plate, the patient again developed compartment syndrome. PMID:26229779

  13. Relationship between Defect Size and Fatigue Life Distributions in Al-7 Pct Si-Mg Alloy Castings

    NASA Astrophysics Data System (ADS)

    Tiryakioğlu, Murat

    2009-07-01

    A new method for predicting the variability in fatigue life of castings was developed by combining the size distribution for the fatigue-initiating defects and a fatigue life model based on the Paris-Erdoğan law for crack propagation. Two datasets for the fatigue-initiating defects in Al-7 pct Si-Mg alloy castings, reported previously in the literature, were used to demonstrate that (1) the size of fatigue-initiating defects follow the Gumbel distribution; (2) the crack propagation model developed previously provides respectable fits to experimental data; and (3) the method developed in the present study expresses the variability in both datasets, almost as well as the lognormal distribution and better than the Weibull distribution.

  14. [Posttraumatic deformities of the knee joint : Intra-articular osteotomy after malreduction of tibial head fractures].

    PubMed

    Frosch, K-H; Krause, M; Frings, J; Drenck, T; Akoto, R; Müller, G; Madert, J

    2016-10-01

    Malreduction of tibial head fractures often leads to malalignment of the lower extremity, pain, limited range of motion and instability. The extent of the complaints and the degree of deformity requires an exact analysis and a standardized approach. True ligamentous instability should be distinguished from pseudoinstability of the joint. Also extra- and intra-articular deformities have to be differentiated. In intra-articular deformities the extent of articular surface displacement, defects and clefts must be accurately evaluated. A specific surgical approach is necessary, which allows adequate visualization, correct osteotomy and refixation of the fractured area of the tibial head. In the long-term course good clinical results are described for intra-articular osteotomies. If the joint is damaged to such an extent that it cannot be reconstructed or in cases of advanced posttraumatic osteoarthritis, total knee arthroplasty may be necessary; however, whenever possible and reasonable, anatomical reconstruction and preservation of the joint should be attempted.

  15. Tibial lengthening over intramedullary nails

    PubMed Central

    Burghardt, R. D.; Manzotti, A.; Bhave, A.; Paley, D.

    2016-01-01

    Objectives The purpose of this study was to compare the results and complications of tibial lengthening over an intramedullary nail with treatment using the traditional Ilizarov method. Methods In this matched case study, 16 adult patients underwent 19 tibial lengthening over nails (LON) procedures. For the matched case group, 17 patients who underwent 19 Ilizarov tibial lengthenings were retrospectively matched to the LON group. Results The mean external fixation time for the LON group was 2.6 months and for the matched case group was 7.6 months. The mean lengthening amounts for the LON and the matched case groups were 5.2 cm and 4.9 cm, respectively. The radiographic consolidation time in the LON group was 6.6 months and in the matched case group 7.6 months. Using a clinical and radiographic outcome score that was designed for this study, the outcome was determined to be excellent in 17 and good in two patients for the LON group. The outcome was excellent in 14 and good in five patients in the matched case group. The LON group had increased blood loss and increased cost. The LON group had four deep infections; the matched case group did not have any deep infections. Conclusions The outcomes in the LON group were comparable with the outcomes in the matched case group. The LON group had a shorter external fixation time but experienced increased blood loss, increased cost, and four cases of deep infection. The advantage of reducing external fixation treatment time may outweigh these disadvantages in patients who have a healthy soft-tissue envelope. Cite this article: J. E. Herzenberg. Tibial lengthening over intramedullary nails: A matched case comparison with Ilizarov tibial lengthening. Bone Joint Res 2016;5:1–10. doi: 10.1302/2046-3758.51.2000577 PMID:26764351

  16. The effects of intrinsic properties and defect structures on the indentation size effect in metals

    NASA Astrophysics Data System (ADS)

    Maughan, Michael R.; Leonard, Ariel A.; Stauffer, Douglas D.; Bahr, David F.

    2017-08-01

    The indentation size effect has been linked to the generation of geometrically necessary dislocations that may be impacted by intrinsic materials properties, such as stacking fault energy, and extrinsic defects, such as statistically stored dislocations. Nanoindentation was carried out at room temperature and elevated temperatures on four different metals in a variety of microstructural conditions. A size effect parameter was determined for each material set combining the effects of temperature and existing dislocation structure. Extrinsic defects, particularly dislocation density, dominate the size effect parameter over those due to intrinsic properties such as stacking fault energy. A multi-mechanism description using a series of mechanisms, rather than a single mechanism, is presented as a phenomenological explanation for the observed size effect in these materials. In this description, the size effect begins with a volume scale dominated by sparse sources, next is controlled by the ability of dislocations to cross-slip and multiply, and then finally at larger length scales work hardening and recovery dominate the effect.

  17. Repairing a critical-sized bone defect with highly porous modified and unmodified baghdadite scaffolds.

    PubMed

    Roohani-Esfahani, S I; Dunstan, C R; Davies, B; Pearce, S; Williams, R; Zreiqat, H

    2012-11-01

    This is the first reported study to prepare highly porous baghdadite (Ca₃ZrSi₂O₉) scaffolds with and without surface modification and investigate their ability to repair critical-sized bone defects in a rabbit radius under normal load. The modification was carried out to improve the mechanical properties of the baghdadite scaffolds (particularly to address their brittleness) by coating their surfaces with a thin layer (∼400 nm) of polycaprolactone (PCL)/bioactive glass nanoparticles (nBGs). The β-tricalcium phosphate/hydroxyapatite (TCP/HA) scaffolds with and without modification were used as the control groups. All of the tested scaffolds had an open and interconnected porous structure with a porosity of ∼85% and average pore size of 500 μm. The scaffolds (six per scaffold type and size of 4 mm × 4 mm × 15 mm) were implanted (press-fit) into the rabbit radial segmental defects for 12 weeks. Micro-computed tomography and histological evaluations were used to determine bone ingrowth, bone quality, and implant integration after 12 weeks of healing. Extensive new bone formation with complete bridging of the radial defect was evident with the baghdadite scaffolds (modified/unmodified) at the periphery and in close proximity to the ceramics within the pores, in contrast to TCP/HA scaffolds (modified/unmodified), where bone tended to grow between the ulna adjacent to the implant edge. Although the modification of the baghdadite scaffolds significantly improved their mechanical properties, it did not show any significant effect on in vivo bone formation. Our findings suggest that baghdadite scaffolds with and without modification can serve as a potential material to repair critical sized bone defects. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  18. Biomimetic coatings for bone tissue engineering of critical-sized defects.

    PubMed

    Liu, Yuelian; Wu, Gang; de Groot, Klaas

    2010-10-06

    The repair of critical-sized bone defects is still challenging in the fields of implantology, maxillofacial surgery and orthopaedics. Current therapies such as autografts and allografts are associated with various limitations. Cytokine-based bone tissue engineering has been attracting increasing attention. Bone-inducing agents have been locally injected to stimulate the native bone-formation activity, but without much success. The reason is that these drugs must be delivered slowly and at a low concentration to be effective. This then mimics the natural method of cytokine release. For this purpose, a suitable vehicle was developed, the so-called biomimetic coating, which can be deposited on metal implants as well as on biomaterials. Materials that are currently used to fill bony defects cannot by themselves trigger bone formation. Therefore, biological functionalization of such materials by the biomimetic method resulted in a novel biomimetic coating onto different biomaterials. Bone morphogenetic protein 2 (BMP-2)-incorporated biomimetic coating can be a solution for a large bone defect repair in the fields of dental implantology, maxillofacial surgery and orthopaedics. Here, we review the performance of the biomimetic coating both in vitro and in vivo.

  19. High tibial osteotomy in knee laxities: Concepts review and results

    PubMed Central

    Robin, Jonathan G.; Neyret, Philippe

    2016-01-01

    Patients with unstable, malaligned knees often present a challenging management scenario, and careful attention must be paid to the clinical history and examination to determine the priorities of treatment. Isolated knee instability treated with ligament reconstruction and isolated knee malalignment treated with periarticular osteotomy have both been well studied in the past. More recently, the effects of high tibial osteotomy on knee instability have been studied. Lateral closing-wedge high tibial osteotomy tends to reduce the posterior tibial slope, which has a stabilising effect on anterior tibial instability that occurs with ACL deficiency. Medial opening-wedge high tibial osteotomy tends to increase the posterior tibia slope, which has a stabilising effect in posterior tibial instability that occurs with PCL deficiency. Overall results from recent studies indicate that there is a role for combined ligament reconstruction and periarticular knee osteotomy. The use of high tibial osteotomy has been able to extend the indication for ligament reconstruction which, when combined, may ultimately halt the evolution of arthritis and preserve their natural knee joint for a longer period of time. Cite this article: Robin JG, Neyret P. High tibial osteotomy in knee laxities: Concepts review and results. EFORT Open Rev 2016;1:3-11. doi: 10.1302/2058-5241.1.000001. PMID:28461908

  20. Histological Analysis of the Tibial Anterior Cruciate Ligament Insertion

    PubMed Central

    Siebold, Rainer; Oka, Shinya; Traut, Ulrike; Schuhmacher, Peter; Kirsch, Joachim

    2017-01-01

    Objective: To describe the morphology of the tibial ACL insertion by histological assessment in the sagittal plane. Methods: For histology the native (undissected) tibial ACL insertion of 6 fresh-frozen cadaveric knees was cut into 4 sagittal sections parallel to the long axis of the medial tibial spine. The slices were stained with hematoxylin and eosin, Safranin O and Russell-Movat pentachrome. All slices were digitalized and analyzed at a magnification of ×20. Results: From medial to lateral the anterior-posterior lengths of the ACL insertion were an average of 10.2, 9.3, 7.6 and 5.8 mm. The anterior margin of the tibial ACL insertion raised from an anterior ridge. The most medial ACL fibers rose along with a peak of the anterior part of the medial tibial spine in which the direct insertion was adjacent to the articular cartilage. Parts of the bony insertions of the anterior and posterior horns of the lateral meniscus were in close contact to the lateral ACL insertion. A small fat pad was located just posterior to the tibial ACL insertion. There were no central or posterolateral inserting ACL fibers in the area intercondylaris anterior. Conclusion: The functional intraligamentous midsubstance ACL fibers arose from the most posterior part of its bony tibial insertion in a flat and “C-shape” way. The anterior border of this functional ACL started from a bony ‘anterior ridge’ and the medial border was along with a peak of the medial tibial spine.

  1. The repeatability of mean defect with size III and size V standard automated perimetry.

    PubMed

    Wall, Michael; Doyle, Carrie K; Zamba, K D; Artes, Paul; Johnson, Chris A

    2013-02-15

    The mean defect (MD) of the visual field is a global statistical index used to monitor overall visual field change over time. Our goal was to investigate the relationship of MD and its variability for two clinically used strategies (Swedish Interactive Threshold Algorithm [SITA] standard size III and full threshold size V) in glaucoma patients and controls. We tested one eye, at random, for 46 glaucoma patients and 28 ocularly healthy subjects with Humphrey program 24-2 SITA standard for size III and full threshold for size V each five times over a 5-week period. The standard deviation of MD was regressed against the MD for the five repeated tests, and quantile regression was used to show the relationship of variability and MD. A Wilcoxon test was used to compare the standard deviations of the two testing methods following quantile regression. Both types of regression analysis showed increasing variability with increasing visual field damage. Quantile regression showed modestly smaller MD confidence limits. There was a 15% decrease in SD with size V in glaucoma patients (P = 0.10) and a 12% decrease in ocularly healthy subjects (P = 0.08). The repeatability of size V MD appears to be slightly better than size III SITA testing. When using MD to determine visual field progression, a change of 1.5 to 4 decibels (dB) is needed to be outside the normal 95% confidence limits, depending on the size of the stimulus and the amount of visual field damage.

  2. Predictive formula for the length of tibial tunnel in anterior crucitate ligament reconstruction.

    PubMed

    Chernchujit, Bancha; Barthel, Thomas

    2009-12-01

    The anterior cruciate ligament (ACL) reconstruction using bone-patellar tendon bone graft is a common procedure in orthopedics. One challenging problem found is a graft-tunnel mismatch. Previous studies have reported the mathematic formula to predict the tibial angle length and angle to avoid graft-tunnel mismatch but these formulas have shown limited predictability. To propose a predictive formula for the length of tibial tunnel and to examine its predictability. Thirty six patients (26 males, 14 females) with ACL injury were included in this study. The preoperativemedial proximal tibial angle was measured. Intraoperatively, the tibial tunnel length and tibial entry point were measured. The postoperative coronal and saggital angle of tibial tunnel were measured from knee radiograph. The data were analysed by using trigonometry correlation and formulate the predictive formula of tibial tunnel length. We found that tibial tunnel length (T) has trigonometric correlation between the location of tibial tunnel entry point (w), coronal angle of tibial tunnel (b), saggital angle of tibial tunnel (a) and the medial proximal tibial slope (c) by using this formula T = Wcos(c)tan(b)/sin(a) This proposed predictive formula can well predict the length of the tibial tunnel at preoperative period to avoid graft-tunnel mismatch.

  3. Rapid and reliable healing of critical size bone defects with genetically modified sheep muscle.

    PubMed

    Liu, F; Ferreira, E; Porter, R M; Glatt, V; Schinhan, M; Shen, Z; Randolph, M A; Kirker-Head, C A; Wehling, C; Vrahas, M S; Evans, C H; Wells, J W

    2015-09-21

    Large segmental defects in bone fail to heal and remain a clinical problem. Muscle is highly osteogenic, and preliminary data suggest that autologous muscle tissue expressing bone morphogenetic protein-2 (BMP-2) efficiently heals critical size defects in rats. Translation into possible human clinical trials requires, inter alia, demonstration of efficacy in a large animal, such as the sheep. Scale-up is fraught with numerous biological, anatomical, mechanical and structural variables, which cannot be addressed systematically because of cost and other practical issues. For this reason, we developed a translational model enabling us to isolate the biological question of whether sheep muscle, transduced with adenovirus expressing BMP-2, could heal critical size defects in vivo. Initial experiments in athymic rats noted strong healing in only about one-third of animals because of unexpected immune responses to sheep antigens. For this reason, subsequent experiments were performed with Fischer rats under transient immunosuppression. Such experiments confirmed remarkably rapid and reliable healing of the defects in all rats, with bridging by 2 weeks and remodelling as early as 3-4 weeks, despite BMP-2 production only in nanogram quantities and persisting for only 1-3 weeks. By 8 weeks the healed defects contained well-organised new bone with advanced neo-cortication and abundant marrow. Bone mineral content and mechanical strength were close to normal values. These data demonstrate the utility of this model when adapting this technology for bone healing in sheep, as a prelude to human clinical trials.

  4. Models of tibial fracture healing in normal and Nf1-deficient mice.

    PubMed

    Schindeler, Aaron; Morse, Alyson; Harry, Lorraine; Godfrey, Craig; Mikulec, Kathy; McDonald, Michelle; Gasser, Jürg A; Little, David G

    2008-08-01

    Delayed union and nonunion are common complications associated with tibial fractures, particularly in the distal tibia. Existing mouse tibial fracture models are typically closed and middiaphyseal, and thus poorly recapitulate the prevailing conditions following surgery on a human open distal tibial fracture. This report describes our development of two open tibial fracture models in the mouse, where the bone is broken either in the tibial midshaft (mid-diaphysis) or in the distal tibia. Fractures in the distal tibial model showed delayed repair compared to fractures in the tibial midshaft. These tibial fracture models were applied to both wild-type and Nf1-deficient (Nf1+/-) mice. Bone repair has been reported to be exceptionally problematic in human NF1 patients, and these patients can also spontaneously develop tibial nonunions (known as congenital pseudarthrosis of the tibia), which are recalcitrant to even vigorous intervention. pQCT analysis confirmed no fundamental differences in cortical or cancellous bone in Nf1-deficient mouse tibiae compared to wild-type mice. Although no difference in bone healing was seen in the tibial midshaft fracture model, the healing of distal tibial fractures was found to be impaired in Nf1+/- mice. The histological features associated with nonunited Nf1+/- fractures were variable, but included delayed cartilage removal, disproportionate fibrous invasion, insufficient new bone anabolism, and excessive catabolism. These findings imply that the pathology of tibial pseudarthrosis in human NF1 is complex and likely to be multifactorial.

  5. Healing of rabbit calvarial critical-sized defects using autogenous bone grafts and fibrin glue.

    PubMed

    Lappalainen, Olli-Pekka; Korpi, Riikka; Haapea, Marianne; Korpi, Jarkko; Ylikontiola, Leena P; Kallio-Pulkkinen, Soili; Serlo, Willy S; Lehenkari, Petri; Sándor, George K

    2015-04-01

    This study aimed to evaluate ossification of cranial bone defects comparing the healing of a single piece of autogenous calvarial bone representing a bone flap as in cranioplasty compared to particulated bone slurry with and without fibrin glue to represent bone collected during cranioplasty. These defect-filling materials were then compared to empty control cranial defects. Ten White New Zealand adult male rabbits had bilateral critical-sized calvarial defects which were left either unfilled as control defects or filled with a single full-thickness piece of autogenous bone, particulated bone, or particulated bone combined with fibrin glue. The defects were left to heal for 6 weeks postoperatively before termination. CT scans of the calvarial specimens were performed. Histomorphometric assessment of hematoxylin-eosin- and Masson trichrome-stained specimens was used to analyze the proportion of new bone and fibrous tissue in the calvarial defects. There was a statistically significant difference in both bone and soft tissue present in all the autogenous bone-grafted defect sites compared to the empty negative control defects. These findings were supported by CT scan findings. While fibrin glue combined with the particulated bone seemed to delay ossification, the healing was more complete compared to empty control non-grafted defects. Autogenous bone grafts in various forms such as solid bone flaps or particulated bone treated with fibrin glue were associated with bone healing which was superior to the empty control defects.

  6. Measurement of Posterior Tibial Slope Using Magnetic Resonance Imaging.

    PubMed

    Karimi, Elham; Norouzian, Mohsen; Birjandinejad, Ali; Zandi, Reza; Makhmalbaf, Hadi

    2017-11-01

    Posterior tibial slope (PTS) is an important factor in the knee joint biomechanics and one of the bone features, which affects knee joint stability. Posterior tibial slope has impact on flexion gap, knee joint stability and posterior femoral rollback that are related to wide range of knee motion. During high tibial osteotomy and total knee arthroplasty (TKA) surgery, proper retaining the mechanical and anatomical axis is important. The aim of this study was to evaluate the value of posterior tibial slope in medial and lateral compartments of tibial plateau and to assess the relationship among the slope with age, gender and other variables of tibial plateau surface. This descriptive study was conducted on 132 healthy knees (80 males and 52 females) with a mean age of 38.26±11.45 (20-60 years) at Imam Reza hospital in Mashhad, Iran. All patients, selected and enrolled for MRI in this study, were admitted for knee pain with uncertain clinical history. According to initial physical knee examinations the study subjects were reported healthy. The mean posterior tibial slope was 7.78± 2.48 degrees in the medial compartment and 6.85± 2.24 degrees in lateral compartment. No significant correlation was found between age and gender with posterior tibial slope ( P ≥0.05), but there was significant relationship among PTS with mediolateral width, plateau area and medial plateau. Comparison of different studies revealed that the PTS value in our study is different from other communities, which can be associated with genetic and racial factors. The results of our study are useful to PTS reconstruction in surgeries.

  7. Ideal tibial intramedullary nail insertion point varies with tibial rotation.

    PubMed

    Walker, Richard M; Zdero, Rad; McKee, Michael D; Waddell, James P; Schemitsch, Emil H

    2011-12-01

    The aim of the study was to investigate how superior entry point varies with tibial rotation and to identify landmarks that can be used to identify suitable radiographs for successful intramedullary nail insertion. The proximal tibia and knee were imaged for 12 cadaveric limbs undergoing 5° increments of internal and external rotation. Medial and lateral arthrotomies were performed, the ideal superior entry point was identified, and a 2-mm Kirschner wire inserted. A second Kirschner wire was sequentially placed at the 5-mm and then the 10-mm position, both medial and lateral to the initial Kirschner wire. Radiographs of the knee were obtained for all increments. The changing position of the ideal nail insertion point was recorded. A 30° arc (range, 25°-40°) provided a suitable anteroposterior radiograph. On the neutral anteroposterior radiograph, the Kirschner wire was 54% ± 1.5% (range, 51-56%) from the medial edge of the tibial plateau. For every 5° of rotation, the Kirschner wire moved 3% of the plateau width. During external rotation, a misleading medial entry point was obtained. A fibular bisector line correlated with an entry point that was ideal or up to 5 mm lateral to this but never medial. The film that best showed the fibular bisector line was between 0° and 10° of internal rotation of the tibia. The fibula head bisector line can be used to avoid choosing external rotation views and, thus, avoid medial insertion points. The current results may help the surgeon prevent malalignment during intramedullary nailing in proximal tibial fractures.

  8. Tibial Stress Injuries: Decisive Diagnosis and Treatment of "Shin Splints."

    ERIC Educational Resources Information Center

    Couture, Christopher J.; Karlson, Kristine A.

    2002-01-01

    Tibial stress injuries, commonly called shin splints, often result when bone remodeling processes adopt inadequately to repetitive stress. Physicians who are caring for athletic patients must have a thorough understanding of this continuum of injuries, including medial tibial stress syndrome and tibial stress fractures, because there are…

  9. Tibial Eminence Involvement With Tibial Plateau Fracture Predicts Slower Recovery and Worse Postoperative Range of Knee Motion.

    PubMed

    Konda, Sanjit R; Driesman, Adam; Manoli, Arthur; Davidovitch, Roy I; Egol, Kenneth A

    2017-07-01

    To examine 1-year functional and clinical outcomes in patients with tibial plateau fractures with tibial eminence involvement. Retrospective analysis of prospectively collected data. Academic Medical Center. All patients who presented with a tibial plateau fracture (Orthopaedic Trauma Association (OTA) 41-B and 41-C). Patients were divided into fractures with a tibial eminence component (+TE) and those without (-TE) cohorts. All patients underwent similar surgical approaches and fixation techniques for fractures. No tibial eminence fractures received fixation specifically. Short musculoskeletal functional assessment (SMFA), pain (Visual Analogue Scale), and knee range-of-motion (ROM) were evaluated at 3, 6, and 12 months postoperatively and compared between cohorts. Two hundred ninety-three patients were included for review. Patients with OTA 41-C fractures were more likely to have an associated TE compared with 41-B fractures (63% vs. 28%, P < 0.01). At 3 months postoperatively, the +TE cohort was noted to have worse knee ROM (75.16 ± 51 vs. 86.82 ± 53 degree, P = 0.06). At 6 months, total SMFA and knee ROM was significantly worse in the +TE cohort (29 ± 17 vs. 21 ± 18, P ≤ 0.01; 115.6 ± 20 vs. 124.1 ± 15, P = 0.01). By 12 months postoperatively, only knee ROM remained significantly worse in the +TE cohort (118.7 ± 15 vs. 126.9 ± 13, P < 0.01). Multivariate analysis revealed that tibial eminence involvement was a significant predictor of ROM at 6 and 12 months and SFMA at 6 months. Body mass index was found to be a significant predictor of ROM and age was a significant predictor of total SMFA at all time points. Knee ROM remains worse throughout the postoperative period in the +TE cohort. Functional outcome improves less rapidly in the +TE cohort but achieves similar results by 1 year. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

  10. Size Does Matter: An Integrative In Vivo-In Silico Approach for the Treatment of Critical Size Bone Defects

    PubMed Central

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

    2014-01-01

    Although bone has a unique restorative capacity, i.e., it has the potential to heal scarlessly, the conditions for spontaneous bone healing are not always present, leading to a delayed union or a non-union. In this work, we use an integrative in vivo - in silico approach to investigate the occurrence of non-unions, as well as to design possible treatment strategies thereof. The gap size of the domain geometry of a previously published mathematical model was enlarged in order to study the complex interplay of blood vessel formation, oxygen supply, growth factors and cell proliferation on the final healing outcome in large bone defects. The multiscale oxygen model was not only able to capture the essential aspects of in vivo non-unions, it also assisted in understanding the underlying mechanisms of action, i.e., the delayed vascularization of the central callus region resulted in harsh hypoxic conditions, cell death and finally disrupted bone healing. Inspired by the importance of a timely vascularization, as well as by the limited biological potential of the fracture hematoma, the influence of the host environment on the bone healing process in critical size defects was explored further. Moreover, dependent on the host environment, several treatment strategies were designed and tested for effectiveness. A qualitative correspondence between the predicted outcomes of certain treatment strategies and experimental observations was obtained, clearly illustrating the model's potential. In conclusion, the results of this study demonstrate that due to the complex non-linear dynamics of blood vessel formation, oxygen supply, growth factor production and cell proliferation and the interactions thereof with the host environment, an integrative in silico-in vivo approach is a crucial tool to further unravel the occurrence and treatments of challenging critical sized bone defects. PMID:25375821

  11. Micro-Nanostructures of Cellulose-Collagen for Critical Sized Bone Defect Healing.

    PubMed

    Aravamudhan, Aja; Ramos, Daisy M; Nip, Jonathan; Kalajzic, Ivo; Kumbar, Sangamesh G

    2018-02-01

    Bone tissue engineering strategies utilize biodegradable polymeric matrices alone or in combination with cells and factors to provide mechanical support to bone, while promoting cell proliferation, differentiation, and tissue ingrowth. The performance of mechanically competent, micro-nanostructured polymeric matrices, in combination with bone marrow stromal cells (BMSCs), is evaluated in a critical sized bone defect. Cellulose acetate (CA) is used to fabricate a porous microstructured matrix. Type I collagen is then allowed to self-assemble on these microstructures to create a natural polymer-based, micro-nanostructured matrix (CAc). Poly (lactic-co-glycolic acid) matrices with identical microstructures serve as controls. Significantly higher number of implanted host cells are distributed in the natural polymer based micro-nanostructures with greater bone density and more uniform cell distribution. Additionally, a twofold increase in collagen content is observed with natural polymer based scaffolds. This study establishes the benefits of natural polymer derived micro-nanostructures in combination with donor derived BMSCs to repair and regenerate critical sized bone defects. Natural polymer based materials with mechanically competent micro-nanostructures may serve as an alternative material platform for bone regeneration. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. [Application of rafting K-wire technique for tibial plateau fractures].

    PubMed

    Zhang, Xing-zhou; Yu, Wei-zhong; Li, Yun-feng; Liu, Yan-hui

    2015-12-01

    To summarize application of rafting K-wires technique for tibial plateau fractures. From January 2013 to January 2015,45 patients with tibial plateau fractures were treated by locking plate with rafting K-wires, including 33 males and 12 females with an average of 44.2 years old ranging from 22 to 56 years old. According to Schatzker classification, 6 cases were type II, 8 were type Ill, 4 were type IV, 4 were type V, and 5 were type VI. Allogeneic bone graft were performed for bone defects. All patients were fixed with two to five K-wires. Part of weight loading were encouraged at 3 months after operation,and full weight-loading were done at 5 months after operation. Postoperative complications were observed,and Rasmussen clinical and radiological assessment were used to evaluate clinical results. All Patients were followed up from 10 to 23 months with average of 14 months. According to Rasmussen clinical and radiological assessment, clinical scores 23.58 ± 6.33, radiological scores were 14.00 ± 6.33; and excellent and good rates were 82.2% and 77.8% respectively. Four patients occurred severe osteoporosis and collapse of articular surface; 5 patients occurred traumatic arthritis. Rafting K-wires technique with anatomized armor plate could effective fix and support platform collapse and joint bone fragments, increase support surface area and reduce postoperative reduction loss rate.

  13. [Bone defect replacement under conditions of transosseous osteosynthesis and titanium nickelide implant application].

    PubMed

    Ir'ianov, Iu M; Ir'ianova, T Iu

    2012-01-01

    In the experiment conducted on 30 Wistar rats, the peculiarities of tibial bone defect replacement under conditions of transosseous osteosynthesis and implantation of titanium nickelide mesh structures were studied using the methods of scanning electron microscopy and x-ray electron probe microanalysis. It was demonstrated that implant osseointegration occured 7 days after surgery, and after 30 days the defect was replaced with bone tissue by the type of primary bone wound healing, thus the organotypical remodeling of regenerated bone took place.

  14. Medial tibial plateau morphology and stress fracture location: A magnetic resonance imaging study.

    PubMed

    Yukata, Kiminori; Yamanaka, Issei; Ueda, Yuzuru; Nakai, Sho; Ogasa, Hiroyoshi; Oishi, Yosuke; Hamawaki, Jun-Ichi

    2017-06-18

    To determine the location of medial tibial plateau stress fractures and its relationship with tibial plateau morphology using magnetic resonance imaging (MRI). A retrospective review of patients with a diagnosis of stress fracture of the medial tibial plateau was performed for a 5-year period. Fourteen patients [three female and 11 male, with an average age of 36.4 years (range, 15-50 years)], who underwent knee MRI, were included. The appearance of the tibial plateau stress fracture and the geometry of the tibial plateau were reviewed and measured on MRI. Thirteen of 14 stress fractures were linear, and one of them stellated on MRI images. The location of fractures was classified into three types. Three fractures were located anteromedially (AM type), six posteromedially (PM type), and five posteriorly (P type) at the medial tibial plateau. In addition, tibial posterior slope at the medial tibial plateau tended to be larger when the fracture was located more posteriorly on MRI. We found that MRI showed three different localizations of medial tibial plateau stress fractures, which were associated with tibial posterior slope at the medial tibial plateau.

  15. Medial tibial plateau morphology and stress fracture location: A magnetic resonance imaging study

    PubMed Central

    Yukata, Kiminori; Yamanaka, Issei; Ueda, Yuzuru; Nakai, Sho; Ogasa, Hiroyoshi; Oishi, Yosuke; Hamawaki, Jun-ichi

    2017-01-01

    AIM To determine the location of medial tibial plateau stress fractures and its relationship with tibial plateau morphology using magnetic resonance imaging (MRI). METHODS A retrospective review of patients with a diagnosis of stress fracture of the medial tibial plateau was performed for a 5-year period. Fourteen patients [three female and 11 male, with an average age of 36.4 years (range, 15-50 years)], who underwent knee MRI, were included. The appearance of the tibial plateau stress fracture and the geometry of the tibial plateau were reviewed and measured on MRI. RESULTS Thirteen of 14 stress fractures were linear, and one of them stellated on MRI images. The location of fractures was classified into three types. Three fractures were located anteromedially (AM type), six posteromedially (PM type), and five posteriorly (P type) at the medial tibial plateau. In addition, tibial posterior slope at the medial tibial plateau tended to be larger when the fracture was located more posteriorly on MRI. CONCLUSION We found that MRI showed three different localizations of medial tibial plateau stress fractures, which were associated with tibial posterior slope at the medial tibial plateau. PMID:28660141

  16. Autogeneous Friction Stir Weld Lack-of-Penetration Defect Detection and Sizing Using Directional Conductivity Measurements with MWM Eddy Current Sensor

    NASA Technical Reports Server (NTRS)

    Goldfine, Neil; Zilberstei, Vladimir; Lawson, Ablode; Kinchen, David; Arbegast, William

    2000-01-01

    Al 2195-T8 plate specimens containing Friction Stir Welds (FSW), provided by Lockheed Martin, were inspected using directional conductivity measurements with the MWM sensor. Sensitivity to lack-of-penetration (LOP) defect size has been demonstrated. The feature used to determine defect size was the normalized longitudinal component of the MWM conductivity measurements. This directional conductivity component was insensitive to the presence of a discrete crack. This permitted correlation of MWM conductivity measurements with the LOP defect size as changes in conductivity were apparently associated with metallurgical features within the first 0.020 in. of the LOP defect zone. Transverse directional conductivity measurements also provided an indication of the presence of discrete cracks. Continued efforts are focussed on inspection of a larger set of welded panels and further refinement of LOP characterization tools.

  17. [Surgical approaches to tibial plateau fractures].

    PubMed

    Krause, Matthias; Müller, Gunnar; Frosch, Karl-Heinz

    2018-06-06

    Intra-articular tibial plateau fractures can present a surgical challenge due to complex injury patterns and compromised soft tissue. The treatment goal is to spare the soft tissue and an anatomical reconstruction of the tibial articular surface. Depending on the course of the fracture, a fracture-specific access strategy is recommended to provide correct positioning of the plate osteosynthesis. While the anterolateral approach is used in the majority of lateral tibial plateau fractures, only one third of the joint surface is visible; however, posterolateral fragments require an individual approach, e. g. posterolateral or posteromedial. If necessary, osteotomy of the femoral epicondyles can improve joint access for reduction control. Injuries to the posterior columns should be anatomically reconstructed and biomechanically correctly addressed via posterior approaches. Bony posterior cruciate ligament tears can be refixed via a minimally invasive posteromedial approach.

  18. Tibial stress injuries: decisive diagnosis and treatment of 'shin splints'.

    PubMed

    Couture, Christopher J; Karlson, Kristine A

    2002-06-01

    Tibial stress injuries, commonly called 'shin splints,' often result when bone remodeling processes adapt inadequately to repetitive stress. Physicians who care for athletic patients need a thorough understanding of this continuum of injuries, including medial tibial stress syndrome and tibial stress fractures, because there are implications for appropriate diagnosis, management, and prevention.

  19. Understanding the etiology of the posteromedial tibial stress fracture.

    PubMed

    Milgrom, Charles; Burr, David B; Finestone, Aharon S; Voloshin, Arkady

    2015-09-01

    Previous human in vivo tibial strain measurements from surface strain gauges during vigorous activities were found to be below the threshold value of repetitive cyclical loading at 2500 microstrain in tension necessary to reduce the fatigue life of bone, based on ex vivo studies. Therefore it has been hypothesized that an intermediate bone remodeling response might play a role in the development of tibial stress fractures. In young adults tibial stress fractures are usually oblique, suggesting that they are the result of failure under shear strain. Strains were measured using surface mounted unstacked 45° rosette strain gauges on the posterior aspect of the flat medial cortex just below the tibial midshaft, in a 48year old male subject while performing vertical jumps, staircase jumps and running up and down stadium stairs. Shear strains approaching 5000 microstrain were recorded during stair jumping and vertical standing jumps. Shear strains above 1250 microstrain were recorded during runs up and down stadium steps. Based on predictions from ex vivo studies, stair and vertical jumping tibial shear strain in the test subject was high enough to potentially produce tibial stress fracture subsequent to repetitive cyclic loading without necessarily requiring an intermediate remodeling response to microdamage. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. A novel locus for split-hand/foot malformation associated with tibial hemimelia (SHFLD syndrome) maps to chromosome region 17p13.1-17p13.3.

    PubMed

    Lezirovitz, Karina; Maestrelli, Sylvia Regina Pedrosa; Cotrim, Nelson Henderson; Otto, Paulo A; Pearson, Peter L; Mingroni-Netto, Regina Celia

    2008-07-01

    Split-hand/foot malformation (SHFM) associated with aplasia of long bones, SHFLD syndrome or Tibial hemimelia-ectrodactyly syndrome is a rare condition with autosomal dominant inheritance, reduced penetrance and an incidence estimated to be about 1 in 1,000,000 liveborns. To date, three chromosomal regions have been reported as strong candidates for harboring SHFLD syndrome genes: 1q42.2-q43, 6q14.1 and 2q14.2. We characterized the phenotype of nine affected individuals from a large family with the aim of mapping the causative gene. Among the nine affected patients, four had only SHFM of the hands and no tibial defects, three had both defects and two had only unilateral tibial hemimelia. In keeping with previous publications of this and other families, there was clear evidence of both variable expression and incomplete penetrance, the latter bearing hallmarks of anticipation. Segregation analysis and multipoint Lod scores calculations (maximum Lod score of 5.03 using the LINKMAP software) using all potentially informative family members, both affected and unaffected, identified the chromosomal region 17p13.1-17p13.3 as the best and only candidate for harboring a novel mutated gene responsible for the syndrome in this family. The candidate gene CRK located within this region was sequenced but no pathogenic mutation was detected.

  1. Surgical Membranes as Directional Delivery Devices to Generate Tissue: Testing in an Ovine Critical Sized Defect Model

    PubMed Central

    Knothe Tate, Melissa L.; Chang, Hana; Moore, Shannon R.; Knothe, Ulf R.

    2011-01-01

    Purpose Pluripotent cells residing in the periosteum, a bi-layered membrane enveloping all bones, exhibit a remarkable regenerative capacity to fill in critical sized defects of the ovine femur within two weeks of treatment. Harnessing the regenerative power of the periosteum appears to be limited only by the amount of healthy periosteum available. Here we use a substitute periosteum, a delivery device cum implant, to test the hypothesis that directional delivery of endogenous periosteal factors enhances bone defect healing. Methods Newly adapted surgical protocols were used to create critical sized, middiaphyseal femur defects in four groups of five skeletally mature Swiss alpine sheep. Each group was treated using a periosteum substitute for the controlled addition of periosteal factors including the presence of collagen in the periosteum (Group 1), periosteum derived cells (Group 2), and autogenic periosteal strips (Group 3). Control group animals were treated with an isotropic elastomer membrane alone. We hypothesized that periosteal substitute membranes incorporating the most periosteal factors would show superior defect infilling compared to substitute membranes integrating fewer factors (i.e. Group 3>Group 2>Group 1>Control). Results Based on micro-computed tomography data, bone defects enveloped by substitute periosteum enabling directional delivery of periosteal factors exhibit superior bony bridging compared to those sheathed with isotropic membrane controls (Group 3>Group 2>Group 1, Control). Quantitative histological analysis shows significantly increased de novo tissue generation with delivery of periosteal factors, compared to the substitute periosteum containing a collagen membrane alone (Group 1) as well as compared to the isotropic control membrane. Greatest tissue generation and maximal defect bridging was observed when autologous periosteal transplant strips were included in the periosteum substitute. Conclusion Periosteum-derived cells as well

  2. Anatomy and classification of the posterior tibial fragment in ankle fractures.

    PubMed

    Bartoníček, Jan; Rammelt, Stefan; Kostlivý, Karel; Vaněček, Václav; Klika, Daniel; Trešl, Ivo

    2015-04-01

    The aim of this study was to analyze the pathoanatomy of the posterior fragment on the basis of a comprehensive CT examination, including 3D reconstructions, in a large patient cohort. One hundred and forty one consecutive individuals with an ankle fracture or fracture-dislocation of types Weber B or Weber C and evidence of a posterior tibial fragment in standard radiographs were included in the study. The mean patient age was 49 years (range 19-83 years). The exclusion criteria were patients below 18 years of age, inability to provide written consent, fractures of the tibial pilon, posttraumatic arthritis and pre-existing deformities. In all patients, post-injury radiographs were obtained in anteroposterior, mortise and lateral views. All patients underwent CT scanning in transverse, sagittal and frontal planes. 3D CT reconstruction was performed in 91 patients. We were able to classify 137 cases into one of the following four types with constant pathoanatomic features: type 1: extraincisural fragment with an intact fibular notch, type 2: posterolateral fragment extending into the fibular notch, type 3: posteromedial two-part fragment involving the medial malleolus, type 4: large posterolateral triangular fragment. In the 4 cases it was not possible to classify the type of the posterior tibial fragment. These were collectively termed type 5 (irregular, osteoporotic fragments). It is impossible to assess the shape and size of the posterior malleolar fragment, involvement of the fibular notch, or the medial malleolus, on the basis of plain radiographs. The system that we propose for classification of fractures of the posterior malleolus is based on CT examination and takes into account the size, shape and location of the fragment, stability of the tibio-talar joint and the integrity of the fibular notch. It may be a useful indication for surgery and defining the most useful approach to these injuries.

  3. Temporary Fixation Using a Long Femoral-tibial Nail to Treat a Displaced Medial Tibial Plateau Fracture in a 90-year-old Patient: A Case Report.

    PubMed

    Batta, V; Sinha, S; Trompeter, A

    2017-01-01

    Tibial plateau fractures are complex injuries in the elderly population. When traditional methods of fixation are not suitable, an alternative method needs to be chosen for a favorable outcome. We demonstrate a previously undescribed treatment for displaced tibial plateau fractures in the very elderly with poor soft-tissue integrity. A 90-year-old woman suffered an open, Gustilo Grade IIIA, displaced fracture of the tibial plateau. An intramedullary knee arthrodesis, the femoral-tibial nail was used to temporarily stabilize her fracture. She was able to weight bear immediately postfixation. A long femoral-tibial nail allows favorable fracture and soft tissue healing, ease of nursing and immediate full weight-bearing. It shows good promise and should be considered as a management option when traditional methods are not applicable in select patients.

  4. Bone stress in runners with tibial stress fracture.

    PubMed

    Meardon, Stacey A; Willson, John D; Gries, Samantha R; Kernozek, Thomas W; Derrick, Timothy R

    2015-11-01

    Combinations of smaller bone geometry and greater applied loads may contribute to tibial stress fracture. We examined tibial bone stress, accounting for geometry and applied loads, in runners with stress fracture. 23 runners with a history of tibial stress fracture & 23 matched controls ran over a force platform while 3-D kinematic and kinetic data were collected. An elliptical model of the distal 1/3 tibia cross section was used to estimate stress at 4 locations (anterior, posterior, medial and lateral). Inner and outer radii for the model were obtained from 2 planar x-ray images. Bone stress differences were assessed using two-factor ANOVA (α=0.05). Key contributors to observed stress differences between groups were examined using stepwise regression. Runners with tibial stress fracture experienced greater anterior tension and posterior compression at the distal tibia. Location, but not group, differences in shear stress were observed. Stepwise regression revealed that anterior-posterior outer diameter of the tibia and the sagittal plane bending moment explained >80% of the variance in anterior and posterior bone stress. Runners with tibial stress fracture displayed greater stress anteriorly and posteriorly at the distal tibia. Elevated tibial stress was associated with smaller bone geometry and greater bending moments about the medial-lateral axis of the tibia. Future research needs to identify key running mechanics associated with the sagittal plane bending moment at the distal tibia as well as to identify ways to improve bone geometry in runners in order to better guide preventative and rehabilitative efforts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Open tibial fractures grade IIIC treated successfully with external fixation, negative-pressure wound therapy and recombinant human bone morphogenetic protein 7.

    PubMed

    Babiak, Ireneusz

    2014-10-01

    The aim of the therapy in open tibial fractures grade III was to cover the bone with soft tissue and achieve healed fracture without persistent infection. Open tibial fractures grade IIIC with massive soft tissue damage require combined orthopaedic, vascular and plastic-reconstructive procedures. Negative-pressure wound therapy (NPWT), used in two consecutive cases with open fracture grade IIIC of the tibia diaphysis, healed extensive soft tissue defect with exposure of the bone. NPWT eventually allowed for wound closure by split skin graft within 21-25 days. Ilizarov external fixator combined with application of recombinant human bone morphogenetic protein-7 at the site of delayed union enhanced definitive bone healing within 16-18 months. © 2012 The Authors. International Wound Journal © 2012 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  6. Tibial stress fracture after computer-navigated total knee arthroplasty.

    PubMed

    Massai, F; Conteduca, F; Vadalà, A; Iorio, R; Basiglini, L; Ferretti, A

    2010-06-01

    A correct alignment of the tibial and femoral component is one of the most important factors determining favourable long-term results of a total knee arthroplasty (TKA). The accuracy provided by the use of the computer navigation systems has been widely described in the literature so that their use has become increasingly popular in recent years; however, unpredictable complications, such as displaced or stress femoral or tibial fractures, have been reported to occur a few weeks after the operation. We present a case of a stress tibial fracture that occurred after a TKA performed with the use of a computer navigation system. The stress fracture, which eventually healed without further complications, occurred at one of the pinhole sites used for the placement of the tibial trackers.

  7. Transmit-receive eddy current probes for defect detection and sizing in steam generator tubes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Obrutsky, L.S.; Cecco, V.S.; Sullivan, S.P.

    1997-02-01

    Inspection of steam generator tubes in aging Nuclear Generating Stations is increasingly important. Defect detection and sizing, especially in defect prone areas such as the tubesheet, support plates and U-bend regions, are required to assess the fitness-for-service of the steam generators. Information about defect morphology is required to address operational integrity issues, i.e., risk of tube rupture, number of tubes at risk, consequential leakage. A major challenge continues to be the detection and sizing of circumferential cracks. Utilities around the world have experienced this type of tube failure. Conventional in-service inspection, performed with eddy current bobbin probes, is ineffectual inmore » detecting circumferential cracks in tubing. It has been demonstrated in CANDU steam generators, with deformation, magnetite and copper deposits that multi-channel probes with transmit-receive eddy current coils are superior to those using surface impedance coils. Transmit-receive probes have strong directional properties, permitting probe optimization according to crack orientation. They are less sensitive to lift-off noise and magnetite deposits and possess good discrimination to internal defects. A single pass C3 array transmit-receive probe developed by AECL can detect and size circumferential stress corrosion cracks as shallow as 40% through-wall. Since its first trial in 1992, it has been used routinely for steam generator in-service inspection of four CANDU plants, preventing unscheduled shutdowns due to leaking steam generator tubes. More recently, a need has surfaced for simultaneous detection of both circumferential and axial cracks. The C5 probe was designed to address this concern. It combines transmit-receive array probe technology for equal sensitivity to axial and circumferential cracks with a bobbin probe for historical reference. This paper will discuss the operating principles of transmit-receive probes, along with inspection results.« less

  8. Osteogenic potential of a chalcone in a critical-size defect in rat calvaria bone.

    PubMed

    Ortolan, Xana Raquel; Fenner, Bruna Proiss; Mezadri, Telmo José; Tames, David Rivero; Corrêa, Rogério; de Campos Buzzi, Fátima

    2014-07-01

    This study describes the bone formation stimulated by the application of a type of chalcone to critical-size defects in rat calvarial bone. Sixty female Wistar rats were divided into 6 groups of 10 animals per group: control (no treatment), vehicle (vaseline) and the chalcone (1-phenyl-3-(4-chlorophenyl)-2-propen-1-one) suspended in vaseline at 10%. A critical-size defect of 5 mm was prepared using a trephine in the calvarial bone, after which the treatment was applied, in a single dose, according to the experimental group. The samples were evaluated macroscopically using ImageJ software, and histologically 30 and 45 days after surgery. At 30 days after surgery, there was significant bone formation (p < 0.05) in the groups treated with chalcone, compared with the other groups. Many active osteoblasts were observed adjacent to the borders of the newly formed bone tissue. 45 days after surgery in the chalcone group, the surgical defects showed complete bone closure. The results of this study suggest that chalcone has significant potential to induce the formation of new bone. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  9. Temporary Fixation Using a Long Femoral-tibial Nail to Treat a Displaced Medial Tibial Plateau Fracture in a 90-year-old Patient: A Case Report

    PubMed Central

    Batta, V; Sinha, S; Trompeter, A

    2017-01-01

    Introduction: Tibial plateau fractures are complex injuries in the elderly population. When traditional methods of fixation are not suitable, an alternative method needs to be chosen for a favorable outcome. We demonstrate a previously undescribed treatment for displaced tibial plateau fractures in the very elderly with poor soft-tissue integrity. Case Report: A 90-year-old woman suffered an open, Gustilo Grade IIIA, displaced fracture of the tibial plateau. An intramedullary knee arthrodesis, the femoral-tibial nail was used to temporarily stabilize her fracture. She was able to weight bear immediately postfixation. Conclusion: A long femoral-tibial nail allows favorable fracture and soft tissue healing, ease of nursing and immediate full weight-bearing. It shows good promise and should be considered as a management option when traditional methods are not applicable in select patients. PMID:29181350

  10. Gender differences in passive knee biomechanical properties in tibial rotation.

    PubMed

    Park, Hyung-Soon; Wilson, Nicole A; Zhang, Li-Qun

    2008-07-01

    The anterior cruciate ligament (ACL) is the most commonly injured knee ligament with the highest incidence of injury in female athletes who participate in pivoting sports. Noncontact ACL injuries commonly occur with both internal and external tibial rotation. ACL impingement against the lateral wall of the intercondylar notch during tibial external rotation and abduction has been proposed as an injury mechanism, but few studies have evaluated in vivo gender-specific differences in laxity and stiffness in external and internal tibial rotations. The purpose of this study was to evaluate these differences. The knees of 10 male and 10 female healthy subjects were rotated between internal and external tibial rotation with the knee at 60 degrees of flexion. Joint laxity, stiffness, and energy loss were compared between male and female subjects. Women had higher laxity (p = 0.01), lower stiffness (p = 0.038), and higher energy loss (p = 0.008) in external tibial rotation than did men. The results suggest that women may be at greater risk of ACL injury resulting from impingement against the lateral wall of the intercondylar notch, which has been shown to be associated with external tibial rotation and abduction.

  11. Observation of nanometer-sized electro-active defects in insulating layers by fluorescence microscopy and electrochemistry.

    PubMed

    Renault, Christophe; Marchuk, Kyle; Ahn, Hyun S; Titus, Eric J; Kim, Jiyeon; Willets, Katherine A; Bard, Allen J

    2015-06-02

    We report a method to study electro-active defects in passivated electrodes. This method couples fluorescence microscopy and electrochemistry to localize and size electro-active defects. The method was validated by comparison with a scanning probe technique, scanning electrochemical microscopy. We used our method for studying electro-active defects in thin TiO2 layers electrodeposited on 25 μm diameter Pt ultramicroelectrodes (UMEs). The permeability of the TiO2 layer was estimated by measuring the oxidation of ferrocenemethanol at the UME. Blocking of current ranging from 91.4 to 99.8% was achieved. Electro-active defects with an average radius ranging between 9 and 90 nm were observed in these TiO2 blocking layers. The distribution of electro-active defects over the TiO2 layer is highly inhomogeneous and the number of electro-active defect increases for lower degree of current blocking. The interest of the proposed technique is the possibility to quickly (less than 15 min) image samples as large as several hundreds of μm(2) while being able to detect electro-active defects of only a few tens of nm in radius.

  12. [APPLICATION OF V-Y ADVANCED SENSE-REMAINED POSTERIOR TIBIAL ARTERY PERFORATOR FLAP IN REPAIRING WOUND AROUND ANKLE].

    PubMed

    Tang, Xiujun; Wang, Bo; Wei, Zairong; Wang, Dali; Han, Wenjie; Zhang, Wenduo; Li, Shujun

    2015-12-01

    OBJECTIVE To explore the feasibility and effectiveness of V-Y advanced sense-remained posterior tibial artery perforator flap in repairing wound around the ankle. METHODS Between March 2012 and January 2015, 11 patients with wounds around the ankle were treated by V-Y advanced sense-remained posterior tibial artery perforator flap. There were 6 males and 5 females with a median age of 37 years (range, 21-56 years). The causes were traffic accident injury in 3 cases, thermal injury in 2 cases, burn in 2 cases, iatrogenic wounds in 2 cases, and local contusion in 2 cases. The disease duration ranged from 1 to 3 weeks (mean, 2 weeks). Injury was located at the medial malleolus in 4 cases, at the lateral malleolus in 3 cases, and at the heel in 4 cases. All had exposure of bone, tendon, or plate. The defect area ranged from 4 cmx2 cm to 5 cmx3 cm; the area of the flap ranged from 11 cmx4 cm to 15 cmx6 cm. Necrosis of distal flap occurred in 1 case after operation; re-operation to amputate the posterior tibial artery was given and the wound was repaired by proximal skin graft. Light necrosis of distal end was observed in 2 cases, and wound healed at 3 weeks after dressing. And other flaps successfully survived, and primary healing of wounds were obtained. The patients were followed up 6-24 months (mean, 11 months). The flaps were good in color, texture, and appearance. The ankle joint had normal activity. At last follow-up, 10 cases restored fine sense, and 1 case restored protective feeling with posterior tibial artery advanced flap after amputation. V-Y advanced sense-remained posterior tibial artery perforator flap has the advantages of reliable blood supply, simple operation, good appearance, and sensory recovery. Therefore, it is an ideal method to repair wound around the ankle.

  13. A high rate of tibial plateau fractures after early experience with patient-specific instrumentation for unicompartmental knee arthroplasties.

    PubMed

    Leenders, A M; Schotanus, M G M; Wind, R J P; Borghans, R A P; Kort, N P

    2018-04-30

    Patient-specific instrumentation (PSI) for unicompartmental knee arthroplasty (UKA) has been available for a few years. However, limited literature is available on this subject. Hence, the aim of this cohort study is to evaluate the 2 years' results of our first experiences with the use of PSI in UKA. It is hypothesised that there is no advantage in rate of adverse events and in radiological and functional outcomes in comparison to literature on the conventional method. This cohort included 129 knees of 122 patients, operated by one surgeon. Outcome measures were the rate of adverse events (AEs); implant position as determined on radiographs; the accuracy of the default and approved planning of the implant sizes and the patient-reported outcome measures (PROMs) preoperatively, and at 3, 12 and 24 months, postoperatively. A total of 6 (4.9%) AEs were observed in this study, with 4 (3.3%) tibial fractures being the main complication. The mean postoperative biomechanical axis was 176.4° and in the majority of cases, the radiographic criteria, as determined by the manufacturer, were met. The tibial component showed 20 (16.4%) outliers in the sagittal and 3 (2.5%) outliers in the frontal plane. There were no outliers of the femoral component. For the femoral and tibial components, respectively, in 125 (96.9%) and 79 (61.7%) cases, there was an agreement between approved planning and implanted component size. All PROMs improved significantly after surgery. Tibial fracture was the most common AE, probably related to the transition from cemented to uncemented UKA. Perioperative modifications to the surgical technique were made in order to prevent this AE. Improvements should be made to the operation technique of the uncemented tibial plateau to obtain an adequate placement and at the same time reduce the risk for tibial fracture. The PSI technique was a reliable tool for the placement of the femoral component. Functional outcome was in line with literature on the

  14. Forefoot-rearfoot coupling patterns and tibial internal rotation during stance phase of barefoot versus shod running.

    PubMed

    Eslami, Mansour; Begon, Mickaël; Farahpour, Nader; Allard, Paul

    2007-01-01

    Based on twisted plate and mitered hinge models of the foot and ankle, forefoot-rearfoot coupling motion patterns can contribute to the amount of tibial rotation. The present study determined the differences of forefoot-rearfoot coupling patterns as well as excessive excursion of tibial internal rotation in shod versus barefoot conditions during running. Sixteen male subjects ran 10 times at 170 steps per minute under the barefoot and shod conditions. Forefoot-rearfoot coupling motions were assessed by measuring mean relative phase angle during five intervals of stance phase for the main effect of five time intervals and two conditions (ANOVA, P<0.05). Tibial internal rotation excursion was compared between the shod and barefoot conditions over the first 50% of stance phase using paired t-test, (P<0.05). Forefoot adduction/abduction and rearfoot eversion/inversion coupling motion patterns were significantly different between the conditions and among the intervals (P<0.05; effect size=0.47). The mean absolute relative angle was significantly modified to 37 degrees in-phase relationship at the heel-strike of running with shoe wears. No significant differences were noted in the tibial internal rotation excursion between shod and barefoot conditions. Significant variations in the forefoot adduction/abduction and rearfoot eversion/inversion coupling patterns could have little effect on the amount of tibial internal rotation excursion. Yet it remains to be determined whether changes in the frontal plane forefoot-rearfoot coupling patterns influence the tibia kinematics for different shoe wears or foot orthotic interventions. The findings question the rational for the prophylactic use of forefoot posting in foot orthoses.

  15. The soleal line: a cause of tibial pseudoperiostitis.

    PubMed

    Levine, A H; Pais, M J; Berinson, H; Amenta, P S

    1976-04-01

    An unusually prominent soleal line (a normal anatomic variant) may mimic periosteal reaction along the posterior margin of the proximal tibial shaft. This area of pseudoperiostitis is differentiated from hyperostoses arising from the anterior tibial tubercle and the interosseous membrane. It is always associated with normal, undisturbed architecture of the underlying bone.

  16. Study on growth techniques and macro defects of large-size Nd:YAG laser crystal

    NASA Astrophysics Data System (ADS)

    Quan, Jiliang; Yang, Xin; Yang, Mingming; Ma, Decai; Huang, Jinqiang; Zhu, Yunzhong; Wang, Biao

    2018-02-01

    Large-size neodymium-doped yttrium aluminum garnet (Nd:YAG) single crystals were grown by the Czochralski method. The extinction ratio and wavefront distortion of the crystal were tested to determine the optical homogeneity. Moreover, under different growth conditions, the macro defects of inclusion, striations, and cracking in the as-grown Nd:YAG crystals were analyzed. Specifically, the inclusion defects were characterized using scanning electron microscopy and energy dispersive spectroscopy. The stresses of growth striations and cracking were studied via a parallel plane polariscope. These results demonstrate that improper growth parameters and temperature fields can enhance defects significantly. Thus, by adjusting the growth parameters and optimizing the thermal environment, high-optical-quality Nd:YAG crystals with a diameter of 80 mm and a total length of 400 mm have been obtained successfully.

  17. Tibial component considerations in bicruciate-retaining total knee arthroplasty: A 3D MRI evaluation of proximal tibial anatomy.

    PubMed

    Saxena, Vishal; Anari, Jason B; Ruutiainen, Alexander T; Voleti, Pramod B; Stephenson, Jason W; Lee, Gwo-Chin

    2016-08-01

    Restoration of normal anatomy and proper ligament balance are theoretical prerequisites for reproducing physiological kinematics with bicruciate-retaining total knee arthroplasty (TKA). The purpose of this study was to use a 3D MRI technique to evaluate the topography of the proximal tibia and outline considerations in tibial component design for bicruciate-retaining TKA. We identified 100 consecutive patients (50 males and 50 females) between ages 20 and 40 years with knee MRIs without arthritis, dysplasia, ACL tears, or prior knee surgery. A novel 3D MRI protocol coordinating axial, coronal, and sagittal images was used to measure: 1) medial and lateral posterior tibial slopes; 2) medial and lateral coronal slopes; and 3) distance from the anterior tibia to the ACL footprint. There was no overall difference in medial and lateral posterior tibial slopes (5.5° (95% CI 5.0 to 6.0°) vs. 5.4° (95% CI 4.8 to 6.0°), respectively (p=0.80)), but 41 patients had side-to-side differences greater than 3°. The medial coronal slope was greater than the lateral coronal slope (4.6° (95% CI 4.0 to 5.1°) vs. 3.3° (95% CI 2.9 to 3.7°), respectively (p<0.0001)). Females had less clearance between the anterior tibia and ACL footprint than males (10.8mm (95% CI 10.4 to 11.2mm) vs. 13.0mm (95% CI 12.5 to 13.5mm), respectively (p<0.0001)). Due to highly variable proximal tibial topography, a monoblock bicruciate-retaining tibial baseplate may not reproduce normal anatomy in all patients. Level IV - Anatomic research study. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Risk factors for tibial implant malpositioning in total knee arthrosplasty-consecutive series of one thousand, four hundred and seventeen cases.

    PubMed

    Gaillard, Romain; Cerciello, Simone; Lustig, Sebastien; Servien, Elvire; Neyret, Philippe

    2017-04-01

    Total knee arthroplasty (TKA) malalignment may result in pain and limited range of motion. The present study assessed the influence of different surgeon's and patient's related factors on the post-operative tibial tray coronal alignment. The charts and the x-rays of a continuous prospective series of 1417 TKAs operated upon between 1987 and 2015 were retrospectively reviewed. The long-leg AP views were performed at two months post-op and the tibial mechanical angle of the tibial tray was measured. Three groups were defined: varus (≤87° n = 167), valgus (≥93° n = 55) and well alignment (88° to 92° n = 1195). The influence of several pre-operative and peri-operative factors was investigated: surgeon handedness and experience (junior or senior), previous tibial osteotomies, Ahlbäck stage of osteoarthritits, pre-operative alignment, height and weight, age at surgery, approach (medial, lateral or tibial tubercle osteotomy), generation of implants, tray fixation, size of the tray and stem lenght. Univariate then multivariate analysis were performed to find out any correlation. Multivariate analysis showed a strong correlation between varus alignment of the tibial tray and pre-operative varus of the lower limb (p = 0.037), increased BMI (p = 0.016) and operated side opposite to the dominant surgeon's arm (p = 0.006). In a similar way a strong correlation was found between valgus alignment and pre-operative valgus of the limb (p = 0.026). Poor alignment of the tibial tray after TKA was associated with pre-operative malalignment of the lower limb, increased BMI and an index knee which was opposite to surgeon's dominant arm.

  19. The Dependence of Atomic Oxygen Undercutting of Protected Polyimide Kapton(tm) H upon Defect Size

    NASA Technical Reports Server (NTRS)

    Snyder, Aaron; deGroh, Kim K.

    2001-01-01

    Understanding the behavior of polymeric materials when exposed to the low-Earth-orbit (LEO) environment is important in predicting performance characteristics such as in-space durability. Atomic oxygen (AO) present in LEO is known to be the principal agent in causing undercutting erosion of SiO(x) protected polyimide Kapton(R) H film, which serves as a mechanically stable blanket material in solar arrays. The rate of undercutting is dependent on the rate of arrival, directionality and energy of the AO with respect to the film surface. The erosion rate also depends on the distribution of the size of defects existing in the protective coating. This paper presents results of experimental ground testing using low energy, isotropic AO flux together with numerical modeling to determine the dependence of undercutting erosion upon defect size.

  20. Importance of tibial slope for stability of the posterior cruciate ligament deficient knee.

    PubMed

    Giffin, J Robert; Stabile, Kathryne J; Zantop, Thore; Vogrin, Tracy M; Woo, Savio L-Y; Harner, Christopher D

    2007-09-01

    Previous studies have shown that increasing tibial slope can shift the resting position of the tibia anteriorly. As a result, sagittal osteotomies that alter slope have recently been proposed for treatment of posterior cruciate ligament (PCL) injuries. Increasing tibial slope with an osteotomy shifts the resting position anteriorly in a PCL-deficient knee, thereby partially reducing the posterior tibial "sag" associated with PCL injury. This shift in resting position from the increased slope causes a decrease in posterior tibial translation compared with the PCL-deficient knee in response to posterior tibial and axial compressive loads. Controlled laboratory study. Three knee conditions were tested with a robotic universal force-moment sensor testing system: intact, PCL-deficient, and PCL-deficient with increased tibial slope. Tibial slope was increased via a 5-mm anterior opening wedge osteotomy. Three external loading conditions were applied to each knee condition at 0 degrees, 30 degrees, 60 degrees, 90 degrees, and 120 degrees of knee flexion: (1) 134-N anterior-posterior (A-P) tibial load, (2) 200-N axial compressive load, and (3) combined 134-N A-P and 200-N axial loads. For each loading condition, kinematics of the intact knee were recorded for the remaining 5 degrees of freedom (ie, A-P, medial-lateral, and proximal-distal translations, internal-external and varus-valgus rotations). Posterior cruciate ligament deficiency resulted in a posterior shift of the tibial resting position to 8.4 +/- 2.6 mm at 90 degrees compared with the intact knee. After osteotomy, tibial slope increased from 9.2 degrees +/- 1.0 degrees in the intact knee to 13.8 degrees +/- 0.9 degrees. This increase in slope reduced the posterior sag of the PCL-deficient knee, shifting the resting position anteriorly to 4.0 +/- 2.0 mm at 90 degrees. Under a 200-N axial compressive load with the osteotomy, an additional increase in anterior tibial translation to 2.7 +/- 1.7 mm at 30 degrees was

  1. Tibial shaft fractures in football players

    PubMed Central

    Chang, Winston R; Kapasi, Zain; Daisley, Susan; Leach, William J

    2007-01-01

    Background Football is officially the most popular sport in the world. In the UK, 10% of the adult population play football at least once a year. Despite this, there are few papers in the literature on tibial diaphyseal fractures in this sporting group. In addition, conflicting views on the nature of this injury exist. The purpose of this paper is to compare our experience of tibial shaft football fractures with the little available literature and identify any similarities and differences. Methods and Results A retrospective study of all tibial football fractures that presented to a teaching hospital was undertaken over a 5 year period from 1997 to 2001. There were 244 tibial fractures treated. 24 (9.8%) of these were football related. All patients were male with a mean age of 23 years (range 15 to 29) and shin guards were worn in 95.8% of cases. 11/24 (45.8%) were treated conservatively, 11/24 (45.8%) by Grosse Kemp intramedullary nail and 2/24 (8.3%) with plating. A difference in union times was noted, conservative 19 weeks compared to operative group 23.9 weeks (p < 0.05). Return to activity was also different in the two groups, conservative 27.6 weeks versus operative 23.3 weeks (p < 0.05). The most common fracture pattern was AO Type 42A3 in 14/24 (58.3%). A high number 19/24 (79.2%) were simple transverse or short oblique fractures. There was a low non-union rate 1/24 (4.2%) and absence of any open injury in our series. Conclusion Our series compared similarly with the few reports available in the literature. However, a striking finding noted by the authors was a drop in the incidence of tibial shaft football fractures. It is likely that this is a reflection of recent compulsory FIFA regulations on shinguards as well as improvements in the design over the past decade since its introduction. PMID:17567522

  2. Balanced Flexion and Extension Gaps Are Not Always of Equal Size.

    PubMed

    Kinsey, Tracy L; Mahoney, Ormonde M

    2018-04-01

    It has been widely accepted in total knee arthroplasty (TKA) that flexion and extension gaps in the disarticulated knee during surgery should be equalized. We hypothesized that tensioning during assessment of the flexion gap can induce temporary widening of the gap due to posterior tibial translation. We aimed to describe posterior tibial translation at flexion gap (90°) assessments and assess the correlation of tibial translation with laxity (flexion space increase) using constrained and non-constrained inserts. Imageless navigation was used to measure flexion angle, tibial position relative to the femoral axis, and lateral/medial laxity in 30 patients undergoing primary TKA. Trialing was conducted using posteriorly stabilized and cruciate retaining trials of the same size to elucidate the association of posterior tibial translation with changes in joint capsule laxity at 90° knee flexion. All patients demonstrated posterior tibial translation during flexion gap assessment relative to their subsequent final implantation [mean ± standard deviation (range), 11.3 ± 4.4 (4-21) mm]. Positive linear correlation [r = 0.69, 95% confidence interval (CI) 0.44-0.84, P ≤ .001] was demonstrated between translations [8.7 ± 2.4 (3-13) mm] and laxity changes [2.9° ± 2.0° (-0.7° to 7.4°)] at 90° of flexion. Posterior tibial translation can cause artifactual widening of the flexion gap during gap balancing in posteriorly stabilized TKA, which can be of sufficient magnitude to alter femoral component size selection for some patients. Recognition and management of these intra-operative dynamics for optimal kinematics could be feasible with the advent of robotic applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Tibial Bowing and Pseudarthrosis in Neurofibromatosis Type 1

    DTIC Science & Technology

    2014-04-01

    Neurofibromatosis Type 1 PRINCIPAL INVESTIGATOR: Dr. David Stevenson CONTRACTING ORGANIZATION: University of Utah SALT LAKE CITY...COVERED 1 April 2013 - 31 March 2014 4. TITLE AND SUBTITLE Tibial Bowing and Pseudarthrosis in Neurofibromatosis Type 1 5a. CONTRACT NUMBER...SUPPLEMENTARY NOTES 14. ABSTRACT Anterolateral tibial bowing is a morbid skeletal manifestation observed in 5% of children with neurofibromatosis

  4. Comparison of volumetric bone mineral density in the tibial region of interest for ACL reconstruction.

    PubMed

    Klein, Scott A; Nyland, John; Caborn, David N M; Kocabey, Yavuz; Nawab, Akbar

    2005-12-01

    Adequate tibial bone mineral density (BMD) is essential to soft tissue graft fixation during anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to compare volumetric bone plug density measurements at the tibial region of interest for ACL reconstruction using a standardized immersion technique and Archimedes' principle. Cancellous bone cores were harvested from the proximal, middle, and distal metaphyseal regions of the lateral tibia and from the standard tibial tunnel location used for ACL reconstruction of 18 cadaveric specimens. Proximal tibial cores displayed 32.6% greater BMD than middle tibial cores and 31.8% greater BMD than distal tibial cores, but did not differ from the BMD of the tibial tunnel cores. Correlational analysis confirmed that the cancellous BMD in the tibial tunnel related to the cancellous BMD of the proximal and distal lateral tibial metaphysis. In conjunction with its adjacent cortical bone, the cancellous BMD of the region used for standard tibial tunnel placement provides an effective foundation for ACL graft fixation. In tibia with poor BMD, bicortical fixation that incorporates cortical bone from the distal tibial tunnel region is recommended.

  5. Cranial tibial thrust: a primary force in the canine stifle.

    PubMed

    Slocum, B; Devine, T

    1983-08-15

    A cranially directed force identified within the canine stifle joint was termed cranial tibial thrust. It was generated during weight bearing by tibial compression, of which the tarsal tendon of the biceps femoris is a major contributor, and by the slope of the tibial plateau, found to have a mean cranially directed inclination of 22.6 degrees. This force may be an important factor in cranial cruciate ligament rupture and in generation of cranial drawer sign.

  6. Neurofibromin Deficiency-Associated Transcriptional Dysregulation Suggests a Novel Therapy for Tibial Pseudoarthrosis in NF1

    PubMed Central

    Paria, Nandina; Cho, Tae-Joon; Choi, In Ho; Kamiya, Nobuhiro; Kayembe, Kay; Mao, Rong; Margraf, Rebecca L.; Obermosser, Gerlinde; Oxendine, Ila; Sant, David W.; Song, Mi Hyun; Stevenson, David A.; Viskochil, David H.; Wise, Carol A.; Kim, Harry K.W.; Rios, Jonathan J

    2014-01-01

    Neurofibromatosis type 1 (NF1) is an autosomal dominant disease caused by mutations in NF1. Among the earliest manifestations is tibial pseudoarthrosis and persistent nonunion after fracture. To further understand the pathogenesis of pseudoarthrosis and the underlying bone remodeling defect, pseudoarthrosis tissue and cells cultured from surgically resected pseudoarthrosis tissue from NF1 individuals were analyzed using whole-exome and whole-transcriptome sequencing as well as genomewide microarray analysis. Genomewide analysis identified multiple genetic mechanisms resulting in somatic bi-allelic NF1 inactivation; no other genes with recurring somatic mutations were identified. Gene expression profiling identified dysregulated pathways associated with neurofibromin deficiency, including phosphoinosital-3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) signaling pathways. Unlike aggressive NF1-associated malignancies, tibial pseudoarthrosis tissue does not harbor a high frequency of somatic mutations in oncogenes or other tumor-suppressor genes, such as p53. However, gene expression profiling indicates pseudoarthrosis tissue has a tumor-promoting transcriptional pattern, despite lacking tumorigenic somatic mutations. Significant over-expression of specific cancer-associated genes in pseudoarthrosis highlights a potential for receptor tyrosine kinase inhibitors to target neurofibromin-deficient pseudoarthrosis and promote proper bone remodeling and fracture healing. PMID:24932921

  7. Total knee arthroplasty and fractures of the tibial plateau

    PubMed Central

    Softness, Kenneth A; Murray, Ryan S; Evans, Brian G

    2017-01-01

    Tibial plateau fractures are common injuries that occur in a bimodal age distribution. While there are various treatment options for displaced tibial plateau fractures, the standard of care is open reduction and internal fixation (ORIF). In physiologically young patients with higher demand and better bone quality, ORIF is the preferred method of treating these fractures. However, future total knee arthroplasty (TKA) is a consideration in these patients as post-traumatic osteoarthritis is a common long-term complication of tibial plateau fractures. In older, lower demand patients, ORIF is potentially less favorable for a variety of reasons, namely fixation failure and the need for delayed weight bearing. In some of these patients, TKA can be considered as primary mode of treatment. This paper will review the literature surrounding TKA as both primary treatment and as a salvage measure in patients with fractures of the tibial plateau. The outcomes, complications, techniques and surgical challenges are also discussed. PMID:28251061

  8. Effect of rhBMP-2 on tibial plateau fractures in a canine model.

    PubMed

    Schaefer, Susan L; Lu, Yan; Seeherman, Howard; Li, X Jian; Lopez, Mandi J; Markel, Mark D

    2009-04-01

    This study was to determine the efficacy of recombinant human bone morphogenetic protien-2 (rhBMP-2)/calcium phosphate matrix (CPX) paste to accelerate healing in a canine articular fracture model with associated subchondral defect. rhBMP-2/CPX (BMP), CPX alone (CPX) or autogenous bone graft (ABG) was administered to a canine articular tibial plateau osteotomy with a subchondral defect in each of 21 female dogs. The unoperated contralateral limbs served as controls. Ground reaction forces, synovial fluid, radiographic changes, mechanical testing, bone density, and histology of bone and synovium were analyzed at 6 weeks after surgery. Radiographic analysis demonstrated that the BMP and CPX groups showed improved bony healing compared to the ABG group at week 6. Histomorphometric analysis demonstrated that the BMP group had significantly increased trabecular bone volume compared to the CPX and ABG groups. Mechanical testing revealed that the BMP group had significantly greater maximum failure loads than the ABG group. Histological analysis demonstrated that the BMP group had significantly less sub-synovial inflammation than CPX group. This study demonstrated that rhBMP-2/CPX accelerated healing of articular fractures with subchondral defect compared to ABG in most of the parameters evaluated, and had less subsynovial inflammation than the CPX alone in a canine model.

  9. Defects versus grain size effects on the ferromagnetism of ZrO2 nanocrystals clarified by positron annihilation

    NASA Astrophysics Data System (ADS)

    Wang, D. D.; Qi, N.; Jiang, M.; Chen, Z. Q.

    2013-01-01

    Undoped ZrO2 nanocrystals were annealed in open air from 100 °C to 1300 °C. X-ray diffraction and transmission electron microscope were used to study the structure change and grain growth. Both the methods reveal that the ZrO2 grain size has very slight increase after annealing up to 900 °C. Positron annihilation measurements reveal a high concentration of vacancy defects which most probably exist in the grain boundary region. Thermal annealing above 500 °C causes recovery of these defects, and after annealing at 1200 °C, most of them are removed. Room temperature ferromagnetism is observed for the sample annealed at 100 °C and 500 °C. The magnetization becomes very weak after the nanocrystals are annealed at 700 °C, and it almost disappears at 1000 °C. It is clear that the intrinsic ferromagnetism in our ZrO2 nanocrystals is mostly related with the interfacial defects instead of grain size effects.

  10. Can the tibial slope be measured on lateral knee radiographs?

    PubMed

    Faschingbauer, M; Sgroi, M; Juchems, M; Reichel, H; Kappe, T

    2014-12-01

    The posterior tibial slope influences both the natural knee stability as well as the stability and kinematics after total knee arthroplasty (TKA). Exact definition of the posterior tibial slope (PTS) requires lateral radiographs of the lower limb. Only lateral knee radiographs are routinely obtained after TKA, however. The purpose of the present study therefore was to analyse the relationship between PTS measurement results on short and expanded lateral knee radiographs. The PTS was measured on 100 consecutive lateral radiographs of the lower limb using the mechanical and three diaphyseal axes with various distances below the tibial plateau. Significant differences between PTS results were found for all three diaphyseal axes, with the smallest differences and the strongest correlation for a diaphyseal axis at 16 and 20 cm below the tibial plateau. Using short distances below the tibial plateau (6 and 10 cm) resulted in an overestimation of the PTS of 3°, on average. The PTS measurements in long lateral knee radiographs are more accurate compared to short radiographs. On short lateral knee radiographs, only a estimation of the PTS can be carried out. Diagnostic study, Level II.

  11. Minimally invasive surgical technique: Percutaneous external fixation combined with titanium elastic nails for selective treatment of tibial fractures.

    PubMed

    Tu, Kai-Kai; Zhou, Xian-Ting; Tao, Zhou-Shan; Chen, Wei-Kai; Huang, Zheng-Liang; Sun, Tao; Zhou, Qiang; Yang, Lei

    2015-12-01

    Several techniques have been described to treat tibial fractures, which respectively remains defects. This article presents a novel intra- and extramedullary fixation technique: percutaneous external fixator combined with titanium elastic nails (EF-TENs system). The purpose of this study is to introduce this new minimally invasive surgical technique and selective treatment of tibial fractures, particularly in segmental fractures, diaphysis fractures accompanied with distal or proximal bone subfissure, or fractures with poor soft-tissue problems. Following ethical approval, thirty-two patients with tibial fractures were treated by the EF-TENs system between January 2010 and December 2012. The follow-up studies included clinical and radiographic examinations. All relevant outcomes were recorded during follow-up. All thirty-two patients were achieved follow-ups. According to the AO classification, 3 Type A, 9 Type B and 20 Type C fractures were included respectively. According to the Anderson-Gustilo classification, there were 5 Type Grade II, 3 Type Grade IIIA and 2 Type Grade IIIB. Among 32 patients, 8 of them were segmental fractures. 12 fractures accompanied with bone subfissure. Results showed no nonunion case, with an average time of 23.7 weeks (range, 14-32 weeks). Among them, there were 3/32 delayed union patients and 0/32 malunion case. 4/32 patients developed a pin track infection and no patient suffered deep infection. The external fixator was removed with a mean time of 16.7 weeks (range, 10-26 weeks). Moreover, only 1/32 patient suffered with the restricted ROM of ankle, none with the restricted ROM of knee. This preliminary study indicated that the EF-TENs system, as a novel intra- and extramedullary fixation technique, had substantial effects on selective treatment of tibial fractures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Posterior tibial slope as a risk factor for anterior cruciate ligament rupture in soccer players.

    PubMed

    Senişik, Seçkin; Ozgürbüz, Cengizhan; Ergün, Metin; Yüksel, Oğuz; Taskiran, Emin; Işlegen, Cetin; Ertat, Ahmet

    2011-01-01

    Anterior cruciate ligament (ACL) is the primary stabilizer of the knee. An impairment of any of the dynamic or static stability providing factors can lead to overload on the other factors and ultimately to deterioration of knee stability. This can result in anterior tibial translation and rupture of the ACL. The purpose of this study was to examine the influence of tibial slope on ACL injury risk on soccer players. A total of 64 elite soccer players and 45 sedentary controls were included in this longitudinal and controlled study. The angle between the tibial mid-diaphysis line and the line between the anterior and posterior edges of the medial tibial plateau was measured as the tibial slope via lateral radiographs. Individual player exposure, and injuries sustained by the participants were prospectively recorded. Eleven ACL injuries were documented during the study period. Tibial slope was not different between soccer players and sedentary controls. Tibial slope in the dominant and non-dominant legs was greater for the injured players compared to the uninjured players. The difference reached a significant level only for the dominant legs (p < 0.001). While the tibial slopes of the dominant and non-dominant legs were not different on uninjured players (p > 0.05), a higher tibial slope was observed in dominant legs of injured players (p < 0.05). Higher tibial slope on injured soccer players compared to the uninjured ones supports the idea that the tibial slope degree might be an important risk factor for ACL injury. Key pointsDominant legs' tibial slopes of the injured players were significantly higher compared to the uninjured players (p < 0.001).Higher tibial slope was determined in dominant legs compared to the non-dominant side, for the injured players (p = 0.042). Different tibial slope measures in dominant and non-dominant legs might be the result of different loading and/or adaptation patterns in soccer.

  13. [Stability, bone healing and loss of correction after valgus realignment of the tibial head. A roentgen stereometry analysis].

    PubMed

    Pape, D; Adam, F; Rupp, S; Seil, R; Kohn, D

    2004-02-01

    In high tibial closing-wedge osteotomies (HTO), closure of an osteotomy gap after resection of a bony wedge can be associated with a fissure of the medial cortex of the tibial head (MCT). The effect of a broken MCT on the recurrence of varus deformity is disputed. In this study, serial roentgen stereometric analysis (RSA) was used to determine the fixation stability of a rigid internal "L" plate after HTO. Full weight lower limb radiographs were used to determine the sagittal alignment in patients with varying degrees of varus malalignment and correction over time. Forty-two patients with varus gonarthrosis stage I-III (Ahlback) were treated with HTO and internal fixation with an L-shaped rigid plate. Patients were followed by serial RSA, conventional radiographs, and clinical evaluation (Hospital of Special Surgery score) over a 12-month period. In 19 of 42 successive patients, an average wedge size of 6.9 degrees was resected leaving the MCT intact (group 1). In 23 of 42 of patients, the MCT was unintentionally fissured during surgery when an average 10.3 degrees -wedge was resected (group 2). In group 2, RSA revealed a fivefold increase in lateral displacement of the distal tibial segment within 3 weeks after HTO. Twelve weeks after HTO, translations between tibial segments were below the accuracy of the RSA setup in the majority of patients. Group 1 patients demonstrated a higher initial fixation stability, less occurrence of varus deformity, and a higher HSS score compared to patients with larger wedge sizes and frequent fracture of the MCT (group 2). Before bone healing is achieved, the integrity of the MCT plays a crucial role for the clinical and radiological outcome after HTO.

  14. Primary Ankle Arthrodesis for Severely Comminuted Tibial Pilon Fractures.

    PubMed

    Al-Ashhab, Mohamed E

    2017-03-01

    Management of severely comminuted, complete articular tibial pilon fractures (Rüedi and Allgöwer type III) remains a challenge, with few treatment options providing good clinical outcomes. Twenty patients with severely comminuted tibial pilon fractures underwent primary ankle arthrodesis with a retrograde calcaneal nail and autogenous fibular bone graft. The fusion rate was 100% and the varus malunion rate was 10%. Fracture union occurred at a mean of 16 weeks (range, 13-18 weeks) postoperatively. Primary ankle arthrodesis is a successful method for treating highly comminuted tibial pilon fractures, having a low complication rate and a high satisfaction score. [Orthopedics. 2017; 40(2):e378-e381.]. Copyright 2016, SLACK Incorporated.

  15. 21 CFR 888.3590 - Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint tibial (hemi-knee) metallic resurfacing... Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis is a device intended to be implanted...

  16. All-Polyethylene Tibial Components: An Analysis of Long-Term Outcomes and Infection.

    PubMed

    Houdek, Matthew T; Wagner, Eric R; Wyles, Cody C; Watts, Chad D; Cass, Joseph R; Trousdale, Robert T

    2016-07-01

    There is debate regarding tibial component modularity and composition in total knee arthroplasty (TKA). Biomechanical studies have suggested improved stress distribution in metal-backed tibias; however, these results have not translated clinically. The purpose of this study was to analyze the outcomes of all-polyethylene components and to compare the results to those with metal-backed components. We reviewed 31,939 patients undergoing a primary TKA over a 43-year period (1970-2013). There were 28,224 (88%) metal-backed and 3715 (12%) all-polyethylene tibial components. The metal-backed and all-polyethylene groups had comparable demographics with respect to gender, age and body mass index (BMI). Mean follow-up was 7 years. The mean survival for all primary TKAs at the 5-, 10-, 20- and 30-year time points was 95%, 89%, 73%, and 57%, respectively. All-polyethylene tibial components were found to have a significantly improved (P < .0001) survivorship when compared with their metal-backed counterparts. All-polyethylene tibial components were also found to have a significantly lower rate of infection, instability, tibial component loosening, and periprosthetic fracture. The all-polyethylene group had improved survival rates in all age groups, except in patients 85 years old or greater, where there was no significant difference. All-polyethylene tibial components had improved survival for all BMI groups except in the morbidly obese (BMI ≥ 40) where there was no significant difference. All-polyethylene tibial components had significantly improved implant survival, reduced rates of postoperative infection, fracture, and tibial component loosening. All polyethylene should be considered for most of the patients, regardless of age and BMI. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Complex Medial Meniscus Tears Are Associated With a Biconcave Medial Tibial Plateau.

    PubMed

    Barber, F Alan; Getelman, Mark H; Berry, Kathy L

    2017-04-01

    To determine whether an association exists between a biconcave medial tibial plateau and complex medial meniscus tears. A consecutive series of stable knees undergoing arthroscopy were evaluated retrospectively with the use of preoperative magnetic resonance imaging (MRI), radiographs, and arthroscopy documented by intraoperative videos. Investigators independently performed blinded reviews of the MRI or videos. Based on the arthroscopy findings, medial tibial plateaus were classified as either biconcave or not biconcave. A transverse coronal plane ridge, separating the front of the tibial plateau from the back near the inner margin of the posterior body of the medial meniscus, was defined as biconcave. The medial plateau slope was calculated with MRI sagittal views. General demographic information, body mass index, and arthroscopically confirmed knee pathology were recorded. A total of 179 consecutive knees were studied from July 2014 through August 2015; 49 (27.2%) biconcave medial tibial plateaus and 130 (72.8%) controls were identified at arthroscopy. Complex medial meniscus tears were found in 103. Patients with a biconcave medial tibial plateau were found to have more complex medial meniscus tears (69.4%) than those without a biconcavity (53.1%) (P = .049) despite having lower body mass index (P = .020). No difference in medial tibial plateau slope was observed for biconcavities involving both cartilage and bone, bone only, or an indeterminate group (P = .47). Biconcave medial tibial plateaus were present in 27.4% of a consecutive series of patients undergoing knee arthroscopy. A biconcave medial tibial plateau was more frequently associated with a complex medial meniscus tear. Level III, case-control study. Copyright © 2016 Arthroscopy Association of North America. All rights reserved.

  18. Total knee replacement-cementless tibial fixation with screws: 10-year results.

    PubMed

    Ersan, Önder; Öztürk, Alper; Çatma, Mehmet Faruk; Ünlü, Serhan; Akdoğan, Mutlu; Ateş, Yalım

    2017-12-01

    The aim of this study was to evaluate the long term clinical and radiological results of cementless total knee replacement. A total of 51 knees of 49 patients (33 female and 16 male; mean age: 61.6 years (range, 29-66 years)) who underwent TKR surgery with a posterior stabilized hydroxyapatite coated knee implant were included in this study. All of the tibial components were fixed with screws. The HSS scores were examined preoperatively and at the final follow-up. Radiological assessment was performed with Knee Society evaluating and scoring system. Kaplan-Meier survival analysis was performed to rule out the survival of the tibial component. The mean HSS scores were 45.8 (range 38-60) and 88.1 (range 61-93), preoperatively and at the final follow-up respectively. Complete radiological assessment was performed for 48 knees. Lucent lines at the tibial component were observed in 4 patients; one of these patients underwent a revision surgery due to the loosening of the tibial component. The 10-year survival rate of a tibial component was 98%. Cementless total knee replacement has satisfactory long term clinical results. Primary fixation of the tibial component with screws provides adequate stability even in elderly patients with good bone quality. Level IV, Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  19. Modified arthroscopic suture fixation of a displaced tibial eminence fracture.

    PubMed

    Lehman, Ronald A; Murphy, Kevin P; Machen, M Shaun; Kuklo, Timothy R

    2003-02-01

    This study describes a new arthroscopic method using a whip-stitch technique for treating a displaced type III tibial eminence fracture. A 12-year-old girl who sustained a displaced type III tibial eminence fracture was treated with arthroscopic fixation using the Arthrosew disposable suture device (Surgical Dynamics, Norwalk, CT) to place a whip stitch into the anterior cruciate ligament (ACL). The Arthrex ACL guide (Arthrex, Naples, FL) was used to reduce the avulsed tibial spine fragment. Sutures were then passed through the tibial tunnel and secured over a bony bridge with the knee in 20 degrees of flexion. At 9 months, the patient has a full range of motion with normal Lachman and anterior drawer testing, and she has returned to competitive basketball. Radiographs show complete fracture healing. KT-1000 and isokinetic testing at 9-month follow-up show only minimal side-to-side differences. The Arthrosew device provides a significant advantage in the treatment of type III and IV fractures of the tibial eminence by obtaining arthroscopic fixation within the substance of the ACL, thus obviating arthrotomy and hardware placement. This technique also restores the proper length and tension to the ACL, and provides a simplified, reproducible method of treatment for this injury.

  20. Bone Regeneration in Rat Cranium Critical-Size Defects Induced by Cementum Protein 1 (CEMP1)

    PubMed Central

    Serrano, Janeth; Romo, Enrique; Bermúdez, Mercedes; Narayanan, A. Sampath; Zeichner-David, Margarita; Santos, Leticia; Arzate, Higinio

    2013-01-01

    Gene therapy approaches to bone and periodontal tissue engineering are being widely explored. While localized delivery of osteogenic factors like BMPs is attractive for promotion of bone regeneration; method of delivery, dosage and side effects could limit this approach. A novel protein, Cementum Protein 1 (CEMP1), has recently been shown to promote regeneration of periodontal tissues. In order to address the possibility that CEMP1 can be used to regenerate other types of bone, experiments were designed to test the effect of hrCEMP1 in the repair/regeneration of a rat calvaria critical-size defect. Histological and microcomputed tomography (µCT) analyses of the calvaria defect sites treated with CEMP1 showed that after 16 weeks, hrCEMP1 is able to induce 97% regeneration of the defect. Furthermore, the density and characteristics of the new mineralized tissues were normal for bone. This study demonstrates that hrCEMP1 stimulates bone formation and regeneration and has therapeutic potential for the treatment of bone defects and regeneration of mineralized tissues. PMID:24265720

  1. Comparison of nanoparticular hydroxyapatite pastes of different particle content and size in a novel scapula defect model

    PubMed Central

    Hruschka, Veronika; Tangl, Stefan; Ryabenkova, Yulia; Heimel, Patrick; Barnewitz, Dirk; Möbus, Günter; Keibl, Claudia; Ferguson, James; Quadros, Paulo; Miller, Cheryl; Goodchild, Rebecca; Austin, Wayne; Redl, Heinz; Nau, Thomas

    2017-01-01

    Nanocrystalline hydroxyapatite (HA) has good biocompatibility and the potential to support bone formation. It represents a promising alternative to autologous bone grafting, which is considered the current gold standard for the treatment of low weight bearing bone defects. The purpose of this study was to compare three bone substitute pastes of different HA content and particle size with autologous bone and empty defects, at two time points (6 and 12 months) in an ovine scapula drillhole model using micro-CT, histology and histomorphometry evaluation. The nHA-LC (38% HA content) paste supported bone formation with a high defect bridging-rate. Compared to nHA-LC, Ostim® (35% HA content) showed less and smaller particle agglomerates but also a reduced defect bridging-rate due to its fast degradation The highly concentrated nHA-HC paste (48% HA content) formed oversized particle agglomerates which supported the defect bridging but left little space for bone formation in the defect site. Interestingly, the gold standard treatment of the defect site with autologous bone tissue did not improve bone formation or defect bridging compared to the empty control. We concluded that the material resorption and bone formation was highly impacted by the particle-specific agglomeration behaviour in this study. PMID:28233833

  2. Multiscale, Converging Defects of Macro-Porosity, Microstructure and Matrix Mineralization Impact Long Bone Fragility in NF1

    PubMed Central

    Kühnisch, Jirko; Seto, Jong; Lange, Claudia; Schrof, Susanne; Stumpp, Sabine; Kobus, Karolina; Grohmann, Julia; Kossler, Nadine; Varga, Peter; Osswald, Monika; Emmerich, Denise; Tinschert, Sigrid; Thielemann, Falk; Duda, Georg; Seifert, Wenke; el Khassawna, Thaqif; Stevenson, David A.; Elefteriou, Florent; Kornak, Uwe; Raum, Kay; Fratzl, Peter; Mundlos, Stefan; Kolanczyk, Mateusz

    2014-01-01

    Bone fragility due to osteopenia, osteoporosis or debilitating focal skeletal dysplasias is a frequent observation in the Mendelian disease Neurofibromatosis type 1 (NF1). To determine the mechanisms underlying bone fragility in NF1 we analyzed two conditional mouse models, Nf1Prx1 (limb knock-out) and Nf1Col1 (osteoblast specific knock-out), as well as cortical bone samples from individuals with NF1. We examined mouse bone tissue with micro-computed tomography, qualitative and quantitative histology, mechanical tensile analysis, small-angle X-ray scattering (SAXS), energy dispersive X-ray spectroscopy (EDX), and scanning acoustic microscopy (SAM). In cortical bone of Nf1Prx1 mice we detected ectopic blood vessels that were associated with diaphyseal mineralization defects. Defective mineral binding in the proximity of blood vessels was most likely due to impaired bone collagen formation, as these areas were completely devoid of acidic matrix proteins and contained thin collagen fibers. Additionally, we found significantly reduced mechanical strength of the bone material, which was partially caused by increased osteocyte volume. Consistent with these observations, bone samples from individuals with NF1 and tibial dysplasia showed increased osteocyte lacuna volume. Reduced mechanical properties were associated with diminished matrix stiffness, as determined by SAM. In line with these observations, bone tissue from individuals with NF1 and tibial dysplasia showed heterogeneous mineralization and reduced collagen fiber thickness and packaging. Collectively, the data indicate that bone fragility in NF1 tibial dysplasia is partly due to an increased osteocyte-related micro-porosity, hypomineralization, a generalized defect of organic matrix formation, exacerbated in the regions of tensional and bending force integration, and finally persistence of ectopic blood vessels associated with localized macro-porotic bone lesions. PMID:24465906

  3. Anterior tibial stress fractures treated with anterior tension band plating in high-performance athletes.

    PubMed

    Cruz, Alexandre Santa; de Hollanda, João Paris Buarque; Duarte, Aires; Hungria Neto, José Soares

    2013-06-01

    The non-surgical treatment of anterior tibial cortex stress fractures requires long periods of abstention from sports activities and often results in non-union. Many different surgical techniques have already been previously described to treat these fractures, but there is no consensus on the best treatment. We describe the outcome of treatment using anterior tibial tension band plating in three high-performance athletes (4 legs) with anterior tibial cortex stress fractures. Tibial osteosynthesis with a 3.5-mm locking compression plate in the anterolateral aspect of the tibia was performed in all patients diagnosed with anterior tibial stress fracture after September 2010 at Santa Casa Hospital. All of the fractures were consolidated within a period of 3 months after surgery, allowing for an early return to pre-injury levels of competitive sports activity. There were no infection, non-union, malunion or anterior knee pain complications. Anterior tibial tension band plating leads to prompt fracture consolidation and is a good alternative for the treatment of anterior tibial cortex stress fractures. Bone grafts were shown to be unnecessary.

  4. Potential sites of compression of tibial nerve branches in foot: a cadaveric and imaging study.

    PubMed

    Ghosh, Sanjib Kumar; Raheja, Shashi; Tuli, Anita

    2013-09-01

    Hypertrophy of abductor hallucis muscle is one of the reported causes of compression of tibial nerve branches in foot, resulting in tarsal tunnel syndrome. In this study, we dissected the foot (including the sole) of 120 lower limbs in 60 human cadavers (45 males and 15 females), aged between 45 and 70 years to analyze the possible impact of abductor hallucis muscle in compression neuropathy of tibial nerve branches. We identified five areas in foot, where tibial nerve branches could be compressed by abductor hallucis. Our findings regarding three of these areas were substantiated by clinical evidence from ultrasonography of ankle and sole region, conducted in the affected foot of 120 patients (82 males and 38 females), aged between 42 and 75 years, who were referred for evaluation of pain and/or swelling in medial side of ankle joint with or without associated heel and/or sole pain. We also assessed whether estimation of parameters for the muscle size could identify patients at risk of having nerve compression due to abductor hallucis muscle hypertrophy. The interclass correlation coefficient for dorso-planter thickness of abductor hallucis muscle was 0.84 (95% CI, 0.63-0.92) and that of medio-lateral width was 0.78 (95% CI, 0.62-0.88) in the imaging study, suggesting both are reliable parameters of the muscle size. Receiver operating characteristic curve analysis showed, if ultrasonographic estimation of dorso-plantar thickness is >12.8 mm and medio-lateral width > 30.66 mm in patients with symptoms of nerve compression in foot, abductor hallucis muscle hypertrophy associated compression neuropathy may be suspected. Copyright © 2012 Wiley Periodicals, Inc.

  5. Metal-backed versus all-polyethylene tibial components in primary total knee arthroplasty

    PubMed Central

    2011-01-01

    Background and purpose The choice of either all-polyethylene (AP) tibial components or metal-backed (MB) tibial components in total knee arthroplasty (TKA) remains controversial. We therefore performed a meta-analysis and systematic review of randomized controlled trials that have evaluated MB and AP tibial components in primary TKA. Methods The search strategy included a computerized literature search (Medline, EMBASE, Scopus, and the Cochrane Central Register of Controlled Trials) and a manual search of major orthopedic journals. A meta-analysis and systematic review of randomized or quasi-randomized trials that compared the performance of tibial components in primary TKA was performed using a fixed or random effects model. We assessed the methodological quality of studies using Detsky quality scale. Results 9 randomized controlled trials (RCTs) published between 2000 and 2009 met the inclusion quality standards for the systematic review. The mean standardized Detsky score was 14 (SD 3). We found that the frequency of radiolucent lines in the MB group was significantly higher than that in the AP group. There were no statistically significant differences between the MB and AP tibial components regarding component positioning, knee score, knee range of motion, quality of life, and postoperative complications. Interpretation Based on evidence obtained from this study, the AP tibial component was comparable with or better than the MB tibial component in TKA. However, high-quality RCTs are required to validate the results. PMID:21895503

  6. Effect of tibial plateau leveling on stability of the canine cranial cruciate-deficient stifle joint: an in vitro study.

    PubMed

    Reif, Ullrich; Hulse, Donald A; Hauptman, Joe G

    2002-01-01

    To evaluate the effect of tibial plateau leveling on joint motion in canine stifle joints in which the cranial cruciate ligament (CCL) had been severed. In vitro cadaver study. Six canine cadaver hind legs. Radiographs of the stifle joints were made to evaluate the tibial plateau angle with respect to the long axis of the tibia. The specimens were mounted in a custom-made testing device to measure cranio-caudal translation of the tibia with respect to the femur. An axial load was applied to the tibia, and its position was recorded in the normal stifle, after transection of the CCL, and after tibial plateau leveling. Further, the amount of caudal tibial thrust was measured in the tibial plateau leveled specimen while series of eight linearly increasing axial tibial loads were applied. Transection of the CCL resulted in cranial tibial translation when axial tibial load was applied. After tibial plateau leveling, axial loading resulted in caudal translation of the tibia. Increasing axial tibial load caused a linear increase in caudal tibial thrust in all tibial plateau-leveled specimens. After tibial plateau leveling, axial tibial load generates caudal tibial thrust, which increases if additional axial load is applied. Tibial plateau leveling osteotomy may prevent cranial translation during weight bearing in dogs with CCL rupture by converting axial load into caudal tibial thrust. The amount of caudal tibial thrust seems to be proportional to the amount of weight bearing. Copyright 2002 by The American College of Veterinary Surgeons

  7. Measurement of bone adjacent to tibial shaft fracture.

    PubMed

    Findlay, S C; Eastell, R; Ingle, B M

    2002-12-01

    Delayed union and non-union are common complications after fracture of the tibial shaft. Response of the surrounding bone as a fracture heals could be monitored using techniques currently used in the study of osteoporosis. The aims of our study were to: (1) evaluate the decrement in bone measurements made close to the fracture using dual-energy X-ray absorptiometry (DXA), quantitative ultrasound (QUS) and peripheral quantitative computed tomography (pQCT); (2) compare values for fractured versus non-fractured leg to determine the duration of decrement in bone measurements; and (3) calculate short-term precision in DXA, QUS and pQCT in order to calculate the ratio of decrement to precision (response ratio, RR) to determine the optimal test for monitoring changes after tibial fracture. The biggest decrement in bone measurements at the ipsilateral limb of 28 patients with tibial shaft fracture was observed at the pQCT tibial trabecular sites (distal = 19%, p<0.0001; proximal 5% = 21%, p<0.001; proximal 10% = 28%, p<0.001) and the ultradistal tibia/fibula measured by DXA (19%, p<0.0001). When comparing Z-scores, the magnitude of decrements at the ipsilateral limb was bigger for variables measured directly at the tibia, both proximal and distal to the fracture. The magnitude of the decrement in ultradistal tibia/fibula BMD decreased as the time since fracture increased ( r = 0.55). When response ratios are considered, pQCT measurements at the distal tibia (RR 6-8) and proximal 5% and 10% trabecular sites (RR 5 and 9 respectively) were found to be the most sensitive to change. Therefore, pQCT of the trabecular regions of either the proximal or distal tibia should prove the most sensitive measurement for monitoring changes in bone adjacent to a tibial shaft fracture.

  8. Ground reaction forces and bone parameters in females with tibial stress fracture.

    PubMed

    Bennell, Kim; Crossley, Kay; Jayarajan, Jyotsna; Walton, Elizabeth; Warden, Stuart; Kiss, Z Stephen; Wrigley, Tim

    2004-03-01

    Tibial stress fracture is a common overuse running injury that results from the interplay of repetitive mechanical loading and bone strength. This research project aimed to determine whether female runners with a history of tibial stress fracture (TSF) differ in ground reaction force (GRF) parameters during running, regional bone density, and tibial bone geometry from those who have never sustained a stress fracture (NSF). Thirty-six female running athletes (13 TSF; 23 NSF) ranging in age from 18 to 44 yr were recruited for this cross-sectional study. The groups were well matched for demographic, training, and menstrual parameters. A force platform measured selected GRF parameters (peak and time to peak for vertical impact and active forces, and horizontal braking and propulsive forces) during overground running at 4.0 m.s.(-1). Lumbar spine, proximal femur, and distal tibial bone mineral density were assessed by dual energy x-ray absorptiometry. Tibial bone geometry (cross-sectional dimensions and areas, and second moments of area) was calculated from a computerized tomography scan at the junction of the middle and distal thirds. There were no significant differences between the groups for any of the GRF, bone density, or tibial bone geometric parameters (P > 0.05). Both TSF and NSF subjects had bone density levels that were average or above average compared with a young adult reference range. Factor analysis followed by discriminant function analysis did not find any combinations of variables that differentiated between TSF and NSF groups. These findings do not support a role for GRF, bone density, or tibial bone geometry in the development of tibial stress fractures, suggesting that other risk factors were more important in this cohort of female runners.

  9. A perfusion bioreactor system efficiently generates cell-loaded bone substitute materials for addressing critical size bone defects.

    PubMed

    Kleinhans, Claudia; Mohan, Ramkumar Ramani; Vacun, Gabriele; Schwarz, Thomas; Haller, Barbara; Sun, Yang; Kahlig, Alexander; Kluger, Petra; Finne-Wistrand, Anna; Walles, Heike; Hansmann, Jan

    2015-09-01

    Critical size bone defects and non-union fractions are still challenging to treat. Cell-loaded bone substitutes have shown improved bone ingrowth and bone formation. However, a lack of methods for homogenously colonizing scaffolds limits the maximum volume of bone grafts. Additionally, therapy robustness is impaired by heterogeneous cell populations after graft generation. Our aim was to establish a technology for generating grafts with a size of 10.5 mm in diameter and 25 mm of height, and thus for grafts suited for treatment of critical size bone defects. Therefore, a novel tailor-made bioreactor system was developed, allowing standardized flow conditions in a porous poly(L-lactide-co-caprolactone) material. Scaffolds were seeded with primary human mesenchymal stem cells derived from four different donors. In contrast to static experimental conditions, homogenous cell distributions were accomplished under dynamic culture. Additionally, culture in the bioreactor system allowed the induction of osteogenic lineage commitment after one week of culture without addition of soluble factors. This was demonstrated by quantitative analysis of calcification and gene expression markers related to osteogenic lineage. In conclusion, the novel bioreactor technology allows efficient and standardized conditions for generating bone substitutes that are suitable for the treatment of critical size defects in humans. © 2015 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial Licence, which permits use, distribution and reproduction in any medium, provided the Contribution is properly cited and is not used for commercial purpose.

  10. Bone microarchitecture of the tibial plateau in skeletal health and osteoporosis.

    PubMed

    Krause, Matthias; Hubert, Jan; Deymann, Simon; Hapfelmeier, Alexander; Wulff, Birgit; Petersik, Andreas; Püschel, Klaus; Amling, Michael; Hawellek, Thelonius; Frosch, Karl-Heinz

    2018-05-07

    Impaired bone structure poses a challenge for the treatment of osteoporotic tibial plateau fractures. As knowledge of region-specific structural bone alterations is a prerequisite to achieving successful long-term fixation, the aim of the current study was to characterize tibial plateau bone structure in patients with osteoporosis and the elderly. Histomorphometric parameters were assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT) in 21 proximal tibiae from females with postmenopausal osteoporosis (mean age: 84.3 ± 4.9 years) and eight female healthy controls (45.5 ± 6.9 years). To visualize region-specific structural bony alterations with age, the bone mineral density (Hounsfield units) was additionally analyzed in 168 human proximal tibiae. Statistical analysis was based on evolutionary learning using globally optimal regression trees. Bone structure deterioration of the tibial plateau due to osteoporosis was region-specific. Compared to healthy controls (20.5 ± 4.7%) the greatest decrease in bone volume fraction was found in the medio-medial segments (9.2 ± 3.5%, p < 0.001). The lowest bone volume was found in central segments (tibial spine). Trabecular connectivity was severely reduced. Importantly, in the anterior and posterior 25% of the lateral and medial tibial plateaux, trabecular support and subchondral cortical bone thickness itself were also reduced. Thinning of subchondral cortical bone and marked bone loss in the anterior and posterior 25% of the tibial plateau should require special attention when osteoporotic patients require fracture fixation of the posterior segments. This knowledge may help to improve the long-term, fracture-specific fixation of complex tibial plateau fractures in osteoporosis. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Comparison of long-term results between osteo-odonto-keratoprosthesis and tibial bone keratoprosthesis.

    PubMed

    Charoenrook, Victor; Michael, Ralph; de la Paz, Maria Fideliz; Temprano, José; Barraquer, Rafael I

    2018-04-01

    To compare the anatomical and the functional results between osteo-odonto-keratoprosthesis (OOKP) and keratoprosthesis using tibial bone autograft (Tibial bone KPro). We reviewed the charts of 258 patients; 145 had OOKP whereas 113 had Tibial bone KPro implanted. Functional success was defined as best corrected visual acuity ≥0.05 on decimal scale and anatomical success as retention of the keratoprosthesis lamina. Kaplan-Meier survival curves were calculated for anatomical and functional survival as well as to estimate the probability of post-op complications. The anatomical survival for both KPro groups was not significantly different and was estimated as 67% for OOKP and 54% for Tibial bone KPro at 10 years after surgery. There was also no difference found after subdividing for primary diagnosis groups such as chemical injury, thermal burn, trachoma and all autoimmune cases combined. Estimated functional survival at 10 years post-surgery was 49% for OOKP and 25% for Tibial bone KPro, which was significantly different. The probability of patients with Tibial bone KPro developing one or more post-operative complications at 10 years after surgery (65%) was significantly higher than those with OOKP (40%). Mucous membrane necrosis and retroprosthetic membrane formation were more common in Tibial bone KPro than OOKP. Both types of autologous biological KPro, OOKP and Tibial bone KPro, had statistically similar rate of keratoprosthesis extrusion. Although functional success rate was significantly higher in OOKP, it may have been influenced by a better visual potential in the patients in this group. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Effect of tibial slope on the stability of the anterior cruciate ligament-deficient knee.

    PubMed

    Voos, James E; Suero, Eduardo M; Citak, Musa; Petrigliano, Frank P; Bosscher, Marianne R F; Citak, Mustafa; Wickiewicz, Thomas L; Pearle, Andrew D

    2012-08-01

    We aimed to quantify the effect of changes in tibial slope on the magnitude of anterior tibial translation (ATT) in the anterior cruciate ligament (ACL)-deficient knee during the Lachman and mechanized pivot shift tests. We hypothesized that increased posterior tibial slope would increase the amount of ATT of an ACL-deficient knee, while leveling the slope of the tibial plateau would decrease the amount of ATT. Lachman and mechanized pivot shift tests were performed on hip-to-toe cadaveric specimens, and ATT of the lateral and the medial compartments was measured using navigation (n = 11). The ACL was then sectioned. Stability testing was repeated, and ATT was recorded. A proximal tibial osteotomy in the sagittal plane was then performed achieving either +5 or -5° of tibial slope variation after which stability testing was repeated (n = 10). Sectioning the ACL resulted in a significant increase in ATT in both the Lachman and mechanized pivot shift tests (P < 0.05). Increasing or decreasing the slope of the tibial plateau had no effect on ATT during the Lachman test (n.s.). During the mechanized pivot shift tests, a 5° increase in posterior slope resulted in a significant increase in ATT compared to the native knee (P < 0.05), while a 5° decrease in slope reduced ATT to a level similar to that of the intact knee. Tibial slope changes did not affect the magnitude of translation during a Lachman test. However, large changes in tibial slope variation affected the magnitude of the pivot shift.

  13. Dynamic behaviour of nanometre-sized defect clusters emitted from an atomic displacement cascade in Au at 50 K

    NASA Astrophysics Data System (ADS)

    Ono, K.; Miyamoto, M.; Arakawa, K.; Birtcher, R. C.

    2017-09-01

    We demonstrate the emission of nanometre-sized defect clusters from an isolated displacement cascade formed by irradiation of high-energy self-ions and their subsequent 1-D motion in Au at 50 K, using in situ electron microscopy. The small defect clusters emitted from a displacement cascade exhibited correlated back-and-forth 1-D motion along the [-1 1 0] direction and coalescence which results in their growth and reduction of their mobility. From the analysis of the random 1-D motion, the diffusivity of the small cluster was evaluated. Correlated 1-D motion and coalescence of clusters were understood via elastic interaction between small clusters. These results provide direct experimental evidence of the migration of small defect clusters and defect cascade evolution at low temperature.

  14. Comparison of Different Periodontal Healing of Critical Size Noncontained and Contained Intrabony Defects in Beagles

    PubMed Central

    Zang, Sheng-Qi; Kang, Shuai; Hu, Xin; Wang, Meng; Wang, Xin-Wen; Zhou, Tao; Wang, Qin-Tao

    2017-01-01

    Background: Regenerative techniques help promote the formation of new attachment and bone filling in periodontal defects. However, the dimensions of intraosseous defects are a key determinant of periodontal regeneration outcomes. In this study, we evaluated the efficacy of use of anorganic bovine bone (ABB) graft in combination with collagen membrane (CM), to facilitate healing of noncontained (1-wall) and contained (3-wall) critical size periodontal defects. Methods: The study began on March 2013, and was completed on May 2014. One-wall (7 mm × 4 mm) and 3-wall (5 mm × 4 mm) intrabony periodontal defects were surgically created bilaterally in the mandibular third premolars and first molars in eight beagles. The defects were treated with ABB in combination with CM (ABB + CM group) or open flap debridement (OFD group). The animals were euthanized at 8-week postsurgery for histological analysis. Two independent Student's t-tests (1-wall [ABB + CM] vs. 1-wall [OFD] and 3-wall [ABB + CM] vs. 3-wall [OFD]) were used to assess between-group differences. Results: The mean new bone height in both 1- and 3-wall intrabony defects in the ABB + CM group was significantly greater than that in the OFD group (1-wall: 4.99 ± 0.70 mm vs. 3.01 ± 0.37 mm, P < 0.05; 3-wall: 3.11 ± 0.59 mm vs. 2.08 ± 0.24 mm, P < 0.05). The mean new cementum in 1-wall intrabony defects in the ABB + CM group was significantly greater than that in their counterparts in the OFD group (5.08 ± 0.68 mm vs. 1.16 ± 0.38 mm; P < 0.05). Likewise, only the 1-wall intrabony defect model showed a significant difference with respect to junctional epithelium between ABB + CM and OFD groups (0.67 ± 0.23 mm vs. 1.12 ± 0.28 mm, P < 0.05). Conclusions: One-wall intrabony defects treated with ABB and CM did not show less periodontal regeneration than that in 3-wall intrabony defect. The noncontained 1-wall intrabony defect might be a more discriminative defect model for further research into periodontal

  15. Promoting Endochondral Bone Repair Using Human Osteoarthritic Articular Chondrocytes.

    PubMed

    Bahney, Chelsea S; Jacobs, Linsey; Tamai, Robert; Hu, Diane; Luan, Tammy F; Wang, Miqi; Reddy, Sanjay; Park, Michelle; Limburg, Sonja; Kim, Hubert T; Marcucio, Ralph; Kuo, Alfred C

    2016-03-01

    Current tissue engineering strategies to heal critical-size bone defects through direct bone formation are limited by incomplete integration of grafts with host bone and incomplete graft vascularization. An alternative strategy for bone regeneration is the use of cartilage grafts that form bone through endochondral ossification. Endochondral cartilages stimulate angiogenesis and are remodeled into bone, but are found in very small quantities in growth plates and healing fractures. We sought to develop engineered endochondral cartilage grafts using osteoarthritic (OA) articular chondrocytes as a cell source. Such chondrocytes often undergo hypertrophy, which is a characteristic of endochondral cartilages. We compared the ability of unmodified human OA (hOA) cartilage and cartilage grafts formed in vitro from hOA chondrocytes to undergo endochondral ossification in mice. Scaffold-free engineered chondrocyte grafts were generated by pelleting chondrocytes, followed by culture with transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein 4. Samples derived from either primary or passaged chondrocytes were implanted subcutaneously into immunocompromised mice. Grafts derived from passaged chondrocytes from three patients were implanted into critical-size tibial defects in mice. Bone formation was assessed with histology after 4 weeks of implantation. The composition of tibial repair tissue was quantified with histomorphometry. Engineered cartilage grafts generated from passaged OA chondrocytes underwent endochondral ossification after implantation either subcutaneously or in bone. Cartilage grafts integrated with host bone at 15 out of 16 junctions. Grafts variably remodeled into woven bone, with the proportion of bony repair tissue in tibial defects ranging from 22% to 85% (average 48%). Bony repair tissue bridged the tibial defects in half of the animals. In contrast, unmodified OA cartilage and engineered grafts formed from primary chondrocytes did not

  16. Tibial Acceleration and Spatiotemporal Mechanics in Distance Runners During Reduced-Body-Weight Conditions.

    PubMed

    Moran, Matthew F; Rickert, Brendan J; Greer, Beau K

    2017-05-01

    Treadmills that unload runners via a differential air-pressure (DAP) bladder (eg, AlterG Anti-Gravity Treadmill) are commonly used to reduce effective body weight (BW) in a clinical setting. However, the relationship between the level of unloading and tibial stress is currently unknown. To determine the relationship between tibial impact acceleration and level of BW unloading during running. Cross-sectional. University motion-analysis laboratory. 15 distance runners (9 male, 6 female; 20.4 ± 2.4 y, 60.1 ± 12.6 kg). Peak tibial acceleration and peak-to-peak tibial acceleration were measured via a uniaxial accelerometer attached to the tibia during a 37-min continuous treadmill run that simulated reduced-BW conditions via a DAP bladder. The trial began with a 10-min run at 100% BW followed by nine 3-min stages where BW was systematically reduced from 95% to 60% in 5% increments. There was no significant relationship between level of BW and either peak tibial acceleration or peak-to-peak tibial acceleration (P > .05). Both heart rate and step rate were significantly reduced with each 5% reduction in BW level (P < .01). Although ground-reaction forces are reduced when running in reduced-BW conditions on a DAP treadmill, tibial shock magnitudes are unchanged as an alteration in spatiotemporal running mechanics (eg, reduced step rate) and may nullify the unloading effect.

  17. The treatment options for posterior malleolar fractures in tibial spiral fractures.

    PubMed

    Guo, Jialiang; Liu, Lei; Yang, Zongyou; Hou, Zhiyong; Chen, Wei; Zhang, Yingze

    2017-09-01

    The posterior malleolar fracture (PMF) in tibial spiral fractures are a common type of complication that occurs in tibial fractures. However, the indication of fixation for posterior fractures is still under debate and varies between different surgeons'. It is not unusual to find the smaller PMF (<25%), which could be treated conservatively within guidelines, treated with internal fixation in clinic. The aim of this study is to evaluate the clinical outcomes of tibial spiral fractures with PMF and provide proper guidance for the treatment of this special fracture. A total of 284 cases of spiral fractures combined with PMF were collected and analyzed. Demographic data, fragment size (classified by 25% involvement of ankle joint), time to weight-bearing and functional scores post-operatively were recorded. The ankle-hindfoot scale of the American Orthopaedic Foot and Ankle Society (AOFAS), a visual analogue scale (VAS) pain score, assessment of dorsiflexion restriction and arthritis scale were used as the main evaluations. Forty patients with a larger PMF (≥25%) and 72 with smaller ones (<25%) were fixed and categorized as the fixation group (FG). In the nonfixation group (NG), the corresponding numbers were four and 168 patients respectively. A total of 279 PMF were classified as large posterolateral triangular fragment carrying the posterior half of the fibular notch and intra-incisural posterolateral fragment involving one-fourth to one-third of the fibular notch. However, no obvious differences were observed in terms of the clinical outcomes in PMF involving one-fourth to one-third of the fibular notch. In the treatment of smaller PMF (<25%) of this type, there were no obvious differences in the functional outcomes between fixed (SF) and nonfixed PMF (SN). Many patients with smaller PMFs were fixated, but functional outcomes of SF were not better than those of SN. There is no need to emphasize other factors guiding the treatment of PMF involving one-fourth to

  18. Enhanced healing of rat calvarial critical size defect with selenium-doped lamellar biocomposites.

    PubMed

    Wang, Yanhua; Lv, Peng; Ma, Zhe; Zhang, Jingcheng

    2013-10-01

    A 3D porous lamellar selenium-containing nano-hydroxyapatite (SeHAN)/chitosan (CS) biocomposite was synthesized. The selenium-containing hydroxyapatite (HA) grains of 150~200 nm in length and 20~30 nm in width were observed by dynamic light scattering and transmission electron microscopy. A combination of X-ray diffraction, Fourier-transform infrared spectroscopy, and SEM indicated that HA particles were uniformly dispersed in chitosan matrix and there was a chemical interaction between chitosan and HA. Then, a standard critical size calvarial bone defect was created in Wistar rats. In group 1, no implant was made in the defect. In groups 2 and 3, HA nanoparticles (HAN)/CS biocomposite and SeHAN/CS biocomposite were implanted into the defect, respectively. After 4 weeks, the histological assessment clearly exhibited no significant changes, only found some living cells anchored in the periphery of the implants. After 8 and 12 weeks, most newly formed osteoid tissue was found in the SeHAN/CS implant group. Additionally, the newly formed osteoid tissue, both at the edge and in the center of implants, was bioactive and neovascularized. Microfocus computerized tomography measurements also confirmed the much better quality of the newly formed bone tissue in SeHAN/CS implant group than that in HAN/CS implant group (p < 0.01). Collectively, the SeHAN/CS biocomposite, as a bioactive bone grafting substitute, significantly enhanced the repair of bone defect.

  19. The Effect of Tibial Plateau Levelling Osteotomy on Stifle Extensor Mechanism Load: A Canine Ex Vivo Study.

    PubMed

    Drew, Jarrod O; Glyde, Mark R; Hosgood, Giselle L; Hayes, Alex J

    2018-02-01

     To evaluate the effect of tibial plateau levelling osteotomy on stifle extensor mechanism load in an ex vivo cruciate-intact canine cadaveric model.   Ex vivo mechanical testing study.  Cadaveric canine pelvic limbs ( n  = 6).  A 21-mm tibial radial osteotomy was performed on pelvic limbs ( n  = 6) prior to being mounted into a load-bearing limb press. The proximal tibial segment was incrementally rotated until the anatomical tibial plateau angle had been rotated to at least 1°. The proportional change in stifle extensor mechanism load between the anatomical tibial plateau angle and the neutralized (∼6.5 degrees) and over-rotated (∼1°) tibial plateau angle was analysed using a one-sample t -test against a null hypothesis of no change. A p -value ≤0.05 was considered significant.  There was no significant change in the stifle extensor mechanism load from the anatomical tibial plateau angle (308 N [261-355 N]) to the neutralized tibial plateau angle (313 N [254-372 N]; p =.81), or from the anatomical tibial plateau angle to the over-rotated tibial plateau angle (303 N [254-352 N; p  = 0.67).  Tibial plateau levelling osteotomy does not significantly alter stifle extensor mechanism load at either a neutralized or over-rotated tibial plateau angle in our cruciate-intact model. Schattauer GmbH Stuttgart.

  20. [Magnetic resonance imaging of tibial periostitis].

    PubMed

    Meyer, X; Boscagli, G; Tavernier, T; Aczel, F; Weber, F; Legros, R; Charlopain, P; Martin, J P

    1998-01-01

    Tibial periostitis frequently occurs in athletes. We present our experience with MRI in a series of 7 patients (11 legs) with this condition. The clinical presentation and scintigraphic scanning suggested the diagnosis. MRI exploration of 11 legs demonstrated a high band-like juxta-osseous signal enhancement of SE and IR T2 weighted sequences in 6 cases, a signal enhancement after i.v. contrast administration in 4. Tibial periostitis is a clinical diagnosis and MRI and scintigraphic findings can be used to assure the differential diagnosis in difficult cases with stress fracture. MRI can visualize juxta-osseous edematous and inflammatory reactions and an increased signal would appear to be characteristic when the band-like image is fixed to the periosteum.

  1. MRI analysis of tibial PCL attachment in a large population of adult patients: reference data for anatomic PCL reconstruction.

    PubMed

    Teng, Yuanjun; Guo, Laiwei; Wu, Meng; Xu, Tianen; Zhao, Lianggong; Jiang, Jin; Sheng, Xiaoyun; Xu, Lihu; Zhang, Bo; Ding, Ning; Xia, Yayi

    2016-09-05

    data of the tibial PCL attachment based on MRI in the sagittal orientation. In analysis of retrospective data from a large population of adult patients, the quantitative values can be used as references to define the inserted angle and depth of the drill guide, and the exact position and size of the tibial PCL tunnel for performing arthroscopic anatomic PCL reconstruction.

  2. Smart Sound Processing for Defect Sizing in Pipelines Using EMAT Actuator Based Multi-Frequency Lamb Waves

    PubMed Central

    García-Gómez, Joaquín; Rosa-Zurera, Manuel; Romero-Camacho, Antonio; Jiménez-Garrido, Jesús Antonio; García-Benavides, Víctor

    2018-01-01

    Pipeline inspection is a topic of particular interest to the companies. Especially important is the defect sizing, which allows them to avoid subsequent costly repairs in their equipment. A solution for this issue is using ultrasonic waves sensed through Electro-Magnetic Acoustic Transducer (EMAT) actuators. The main advantage of this technology is the absence of the need to have direct contact with the surface of the material under investigation, which must be a conductive one. Specifically interesting is the meander-line-coil based Lamb wave generation, since the directivity of the waves allows a study based in the circumferential wrap-around received signal. However, the variety of defect sizes changes the behavior of the signal when it passes through the pipeline. Because of that, it is necessary to apply advanced techniques based on Smart Sound Processing (SSP). These methods involve extracting useful information from the signals sensed with EMAT at different frequencies to obtain nonlinear estimations of the depth of the defect, and to select the features that better estimate the profile of the pipeline. The proposed technique has been tested using both simulated and real signals in steel pipelines, obtaining good results in terms of Root Mean Square Error (RMSE). PMID:29518927

  3. Tibial component alignment and risk of loosening in unicompartmental knee arthroplasty: a radiographic and radiostereometric study.

    PubMed

    Barbadoro, P; Ensini, A; Leardini, A; d'Amato, M; Feliciangeli, A; Timoncini, A; Amadei, F; Belvedere, C; Giannini, S

    2014-12-01

    Unicompartmental knee arthroplasty (UKA) has shown a higher rate of revision compared with total knee arthroplasty. The success of UKA depends on prosthesis component alignment, fixation and soft tissue integrity. The tibial cut is the crucial surgical step. The hypothesis of the present study is that tibial component malalignment is correlated with its risk of loosening in UKA. This study was performed in twenty-three patients undergoing primary cemented unicompartmental knee arthroplasties. Translations and rotations of the tibial component and the maximum total point motion (MTPM) were measured using radiostereometric analysis at 3, 6, 12 and 24 months. Standard radiological evaluations were also performed immediately before and after surgery. Varus/valgus and posterior slope of the tibial component and tibial-femoral axes were correlated with radiostereometric micro-motion. A survival analysis was also performed at an average of 5.9 years by contacting patients by phone. Varus alignment of the tibial component was significantly correlated with MTPM, anterior tibial sinking, varus rotation and anterior and medial translations from radiostereometry. The posterior slope of the tibial component was correlated with external rotation. The survival rate at an average of 5.9 years was 89%. The two patients who underwent revision presented a tibial component varus angle of 10° for both. There is correlation between varus orientation of the tibial component and MTPM from radiostereometry in unicompartmental knee arthroplasties. Particularly, a misalignment in varus larger than 5° could lead to risk of loosening the tibial component. Prognostic studies-retrospective study, Level II.

  4. Chitosan-Graphene Oxide 3D scaffolds as Promising Tools for Bone Regeneration in Critical-Size Mouse Calvarial Defects.

    PubMed

    Hermenean, Anca; Codreanu, Ada; Herman, Hildegard; Balta, Cornel; Rosu, Marcel; Mihali, Ciprian Valentin; Ivan, Alexandra; Dinescu, Sorina; Ionita, Mariana; Costache, Marieta

    2017-11-30

    Limited self-regenerating capacity of human skeleton makes the reconstruction of critical size bone defect a significant challenge for clinical practice. Aimed for regenerating bone tissues, this study was designed to investigate osteogenic differentiation, along with bone repair capacity of 3D chitosan (CHT) scaffolds enriched with graphene oxide (GO) in critical-sized mouse calvarial defect. Histopathological/histomorphometry and scanning electron microscopy(SEM) analysis of the implants revealed larger amount of new bone in the CHT/GO-filled defects compared with CHT alone (p < 0.001). When combined with GO, CHT scaffolds synergistically promoted the increase of alkaline phosphatase activity both in vitro and in vivo experiments. This enhanced osteogenesis was corroborated with increased expression of bone morphogenetic protein (BMP) and Runx-2 up to week 4 post-implantation, which showed that GO facilitates the differentiation of osteoprogenitor cells. Meanwhile, osteogenesis was promoted by GO at the late stage as well, as indicated by the up-regulation of osteopontin and osteocalcin at week 8 and overexpressed at week 18, for both markers. Our data suggest that CHT/GO biomaterial could represent a promising tool for the reconstruction of large bone defects, without using exogenous living cells or growth factors.

  5. Influence of the posterior tibial slope on the flexion gap in total knee arthroplasty.

    PubMed

    Okazaki, Ken; Tashiro, Yasutaka; Mizu-uchi, Hideki; Hamai, Satoshi; Doi, Toshio; Iwamoto, Yukihide

    2014-08-01

    Adjusting the joint gap length to be equal in both extension and flexion is an important issue in total knee arthroplasty (TKA). It is generally acknowledged that posterior tibial slope affects the flexion gap; however, the extent to which changes in the tibial slope angle directly affect the flexion gap remains unclear. This study aimed to clarify the influence of tibial slope changes on the flexion gap in cruciate-retaining (CR) or posterior-stabilizing (PS) TKA. The flexion gap was measured using a tensor device with the femoral trial component in 20 cases each of CR- and PS-TKA. A wedge plate with a 5° inclination was placed on the tibial cut surface by switching its front-back direction to increase or decrease the tibial slope by 5°. The flexion gap after changing the tibial slope was compared to that of the neutral slope measured with a flat plate that had the same thickness as that of the wedge plate center. When the tibial slope decreased or increased by 5°, the flexion gap decreased or increased by 1.9 ± 0.6mm or 1.8 ± 0.4mm, respectively, with CR-TKA and 1.2 ± 0.4mm or 1.1 ± 0.3mm, respectively, with PS-TKA. The influence of changing the tibial slope by 5° on the flexion gap was approximately 2mm with CR-TKA and 1mm with PS-TKA. This information is useful when considering the effect of manipulating the tibial slope on the flexion gap when performing CR- or PS-TKA. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Pseudoaneurysm of the Anterior Tibial Artery following Ankle Arthroscopy in a Soccer Player.

    PubMed

    Tonogai, Ichiro; Matsuura, Tetsuya; Iwame, Toshiyuki; Wada, Keizo; Takasago, Tomoya; Goto, Tomohiro; Hamada, Daisuke; Kawatani, Yohei; Fujimoto, Eiki; Kitagawa, Tetsuya; Takao, Shyoichiro; Iwamoto, Seiji; Yamanaka, Moriaki; Harada, Masafumi; Sairyo, Koichi

    2017-01-01

    Ankle arthroscopy carries a lower risk of vascular complications when standard anterolateral and anteromedial portals are used. However, the thickness of the fat pad at the anterior ankle affords little protection for the thin-walled anterior tibial artery, rendering it susceptible to indirect damage during procedures performed on the anterior ankle joint. To our knowledge, only 11 cases of pseudoaneurysm involving the anterior tibial artery after ankle arthroscopy have been described in the literature. Here we reported a rare case of a 19-year-old soccer player who presented with pseudoaneurysm of the anterior tibial artery following ankle arthroscopy using an ankle distraction method and underwent anastomosis for the anterior tibial artery injury. Excessive distraction of the ankle puts the neurovascular structures at greater risk for iatrogenic injury of the anterior tibial artery during ankle arthroscopy. Surgeons should look carefully for postoperative ankle swelling and pain after ankle arthroscopy.

  7. Pseudoaneurysm of the Anterior Tibial Artery following Ankle Arthroscopy in a Soccer Player

    PubMed Central

    Iwame, Toshiyuki; Hamada, Daisuke; Fujimoto, Eiki; Kitagawa, Tetsuya; Takao, Shyoichiro; Iwamoto, Seiji; Yamanaka, Moriaki; Harada, Masafumi

    2017-01-01

    Ankle arthroscopy carries a lower risk of vascular complications when standard anterolateral and anteromedial portals are used. However, the thickness of the fat pad at the anterior ankle affords little protection for the thin-walled anterior tibial artery, rendering it susceptible to indirect damage during procedures performed on the anterior ankle joint. To our knowledge, only 11 cases of pseudoaneurysm involving the anterior tibial artery after ankle arthroscopy have been described in the literature. Here we reported a rare case of a 19-year-old soccer player who presented with pseudoaneurysm of the anterior tibial artery following ankle arthroscopy using an ankle distraction method and underwent anastomosis for the anterior tibial artery injury. Excessive distraction of the ankle puts the neurovascular structures at greater risk for iatrogenic injury of the anterior tibial artery during ankle arthroscopy. Surgeons should look carefully for postoperative ankle swelling and pain after ankle arthroscopy. PMID:28607785

  8. A 3D finite element model to investigate prosthetic interface stresses of different posterior tibial slope.

    PubMed

    Shen, Yi; Li, Xiaomiao; Fu, Xiaodong; Wang, Weili

    2015-11-01

    Posterior tibial slope that is created during proximal tibial resection in total knee arthroplasty has emerged as an important factor in the mechanics of the knee joint and the surgical outcome. But the ideal degree of posterior tibial slope for recovery of the knee joint function and preventions of complications remains controversial and should vary in different racial groups. The objective of this paper is to investigate the effects of posterior tibial slope on contact stresses in the tibial polyethylene component of total knee prostheses. Three-dimensional finite element analysis was used to calculate contact stresses in tibial polyethylene component of total knee prostheses subjected to a compressive load. The 3D finite element model of total knee prosthesis was constructed from the images produced by 3D scanning technology. Stresses in tibial polyethylene component were calculated with four different posterior tibial slopes (0°, 3°, 6° and 9°). The 3D finite element model of total knee prosthesis we presented was well validated. We found that the stress distribution in the polythene as evaluated by the distributions of the von Mises stress, the maximum principle stress, the minimum principle stress and the Cpress were more uniform with 3° and 6° posterior tibial slopes than with 0° and 9° posterior tibial slopes. Moreover, the peaks of the above stresses and trends of changes with increasing degree of knee flexion were more ideal with 3° and 6° posterior slopes. The results suggested that the tibial component inclination might be favourable to 7°-10° so far as the stress distribution is concerned. The range of the tibial component inclination also can decrease the wear of polyethylene. Chinese posterior tibial slope is bigger than in the West, and the current domestic use of prostheses is imported from the West, so their demands to tilt back bone cutting can lead to shorten the service life of prostheses; this experiment result is of important

  9. The Tibial Slope in Patients With Achondroplasia: Its Characterization and Possible Role in Genu Recurvatum Development.

    PubMed

    Brooks, Jaysson T; Bernholt, David L; Tran, Kevin V; Ain, Michael C

    2016-06-01

    Genu recurvatum, a posterior resting position of the knee, is a common lower extremity deformity in patients with achondroplasia and has been thought to be secondary to ligamentous laxity. To the best of our knowledge, the role of the tibial slope has not been investigated, and no studies describe the tibial slope in patients with achondroplasia. Our goals were to characterize the tibial slope in children and adults with achondroplasia, explore its possible role in the development of genu recurvatum, and compare the tibial slope in patients with achondroplasia to that in the general population. We reviewed 252 lateral knee radiographs of 130 patients with achondroplasia seen at our clinic from November 2007 through September 2013. Patients were excluded if they had previous lower extremity surgery or radiographs with extreme rotation. We analyzed patient demographics and, on all radiographs, the tibial slope. We then compared the mean tibial slope to norms in the literature. Tibial slopes >90 degrees had an anterior tibial slope and received a positive prefix. Statistical analysis included intraclass and interclass reliability, Pearson correlation coefficient, and the Student t tests (significance, P<0.05). The overall mean tibial slope for the 252 knees was +1.32±7 degrees, which was significantly more anterior than the normal slopes reported in the literature for adults (7.2 to 10.7 degrees, P=0.0001) and children (10 to 11 degrees, P=0.0001). The Pearson correlation coefficient for mean tibial slope and age showed negative correlations of -0.4011 and -0.4335 for left and right knees, respectively. This anterior tibial slope produces proximal and posterior vector force components, which may shift the knee posteriorly in weightbearing. The mean tibial slope is significantly more anterior in patients with achondroplasia than in the general population; however, this difference diminishes as patients' age. An anterior tibial slope may predispose to a more posterior

  10. Effects of diabetic peripheral neuropathy on gait in vascular trans-tibial amputees.

    PubMed

    Nakajima, Hiroshi; Yamamoto, Sumiko; Katsuhira, Junji

    2018-07-01

    Patients with diabetes often develop diabetic peripheral neuropathy, which is a distal symmetric polyneuropathy, so foot function on the non-amputated side is expected to affect gait in vascular trans-tibial amputees. However, there is little information on the kinematics and kinetics of gait or the effects of diabetic peripheral neuropathy in vascular trans-tibial amputees. This study aimed to clarify these effects, including the biomechanics of the ankle on the non-amputated side. Participants were 10 vascular trans-tibial amputees with diabetic peripheral neuropathy (group V) and 8 traumatic trans-tibial amputees (group T). Each subject's gait was analyzed at a self-selected speed using a three-dimensional motion analyzer and force plates. Ankle plantarflexion angle, heel elevation angle, and peak and impulse of anterior ground reaction force were smaller on the non-amputated side during pre-swing in group V than in group T. Center of gravity during pre-swing on the non-amputated side was lower in group V than in group T. Hip extension torque during loading response on the prosthetic side was greater in group V than in group T. These findings suggest that the biomechanical function of the ankle on the non-amputated side during pre-swing is poorer in vascular trans-tibial amputees with DPN than in traumatic trans-tibial amputees; the height of the center of gravity could not be maintained during this phase in vascular trans-tibial amputees with diabetic peripheral neuropathy. The hip joint on the prosthetic side compensated for this diminished function at the ankle during loading response. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Avulsion of the tibial tuberosity in a litter of greyhound puppies.

    PubMed

    Skelly, C M; McAllister, H; Donnelly, W J

    1997-10-01

    Avulsion of the tibial tuberosity was diagnosed in six of seven greyhound littermates aged five and a half months. The puppies showed hindlimb lameness of varying severity. Radiological assessment of affected stifle joints revealed partial or complete avulsion of the tibial tuberosities. In four puppies the lesions were bilateral. Euthanasia of the two most severely affected puppies was performed; the changes observed on histopathological examination of their cranioproximal tibiae suggested that the underlying lesion was that of osteochondrosis. A hereditary predisposition in greyhounds to osteochondrosis of the physis between the apophysis and the cranioproximal tibial diaphysis is postulated.

  12. Repair of Segmental Load-Bearing Bone Defect by Autologous Mesenchymal Stem Cells and Plasma-Derived Fibrin Impregnated Ceramic Block Results in Early Recovery of Limb Function

    PubMed Central

    Ng, Min Hwei; Duski, Suryasmi; Tan, Kok Keong; Yusof, Mohd Reusmaazran; Low, Kiat Cheong; Mohamed Rose, Isa; Mohamed, Zahiah; Bin Saim, Aminuddin; Idrus, Ruszymah Bt Hj

    2014-01-01

    Calcium phosphate-based bone substitutes have not been used to repair load-bearing bone defects due to their weak mechanical property. In this study, we reevaluated the functional outcomes of combining ceramic block with osteogenic-induced mesenchymal stem cells and platelet-rich plasma (TEB) to repair critical-sized segmental tibial defect. Comparisons were made with fresh marrow-impregnated ceramic block (MIC) and partially demineralized allogeneic bone block (ALLO). Six New Zealand White female rabbits were used in each study group and three rabbits with no implants were used as negative controls. By Day 90, 4/6 rabbits in TEB group and 2/6 in ALLO and MIC groups resumed normal gait pattern. Union was achieved significantly faster in TEB group with a radiological score of 4.50 ± 0.78 versus ALLO (1.06 ± 0.32), MIC (1.28 ± 0.24), and negative controls (0). Histologically, TEB group scored the highest percentage of new bone (82% ± 5.1%) compared to ALLO (5% ± 2.5%) and MIC (26% ± 5.2%). Biomechanically, TEB-treated tibiae achieved the highest compressive strength (43.50 ± 12.72 MPa) compared to those treated with ALLO (15.15 ± 3.57 MPa) and MIC (23.28 ± 6.14 MPa). In conclusion, TEB can repair critical-sized segmental load-bearing bone defects and restore limb function. PMID:25165699

  13. Automated Measurement of Patient-Specific Tibial Slopes from MRI

    PubMed Central

    Amerinatanzi, Amirhesam; Summers, Rodney K.; Ahmadi, Kaveh; Goel, Vijay K.; Hewett, Timothy E.; Nyman, Edward

    2017-01-01

    Background: Multi-planar proximal tibial slopes may be associated with increased likelihood of osteoarthritis and anterior cruciate ligament injury, due in part to their role in checking the anterior-posterior stability of the knee. Established methods suffer repeatability limitations and lack computational efficiency for intuitive clinical adoption. The aims of this study were to develop a novel automated approach and to compare the repeatability and computational efficiency of the approach against previously established methods. Methods: Tibial slope geometries were obtained via MRI and measured using an automated Matlab-based approach. Data were compared for repeatability and evaluated for computational efficiency. Results: Mean lateral tibial slope (LTS) for females (7.2°) was greater than for males (1.66°). Mean LTS in the lateral concavity zone was greater for females (7.8° for females, 4.2° for males). Mean medial tibial slope (MTS) for females was greater (9.3° vs. 4.6°). Along the medial concavity zone, female subjects demonstrated greater MTS. Conclusion: The automated method was more repeatable and computationally efficient than previously identified methods and may aid in the clinical assessment of knee injury risk, inform surgical planning, and implant design efforts. PMID:28952547

  14. Bone tissue ultrastructural defects in a mouse model for osteogenesis imperfecta: a Raman spectroscopy study

    NASA Astrophysics Data System (ADS)

    Chen, Tsoching; Kozloff, Kenneth M.; Goldstein, Steven A.; Morris, Michael D.

    2004-07-01

    Osteogenesis imperfecta (OI) is genetic defect in which the genes that code for the α1(I) or α2(I) chains of type I collagen are defective. The defects often result in substitution of a bulky amino acid for glycine, causing formation of collagen that can not form the normal triple helix. Depending on the details of the defects, the outcomes range from controllable to lethal. This study focuses on OI type IV, a more common and moderately severe form of the disease. People with the disease have a substantial increase in the risk and rate of fracture. We examine the spectroscopic consequences of these defects, using a mouse model (BRTL) that mimics OI type IV. We compare Raman images from tibial cortical tissue of wild-type mice and BRTL mice with single copy of mutation and show that both mineral to matrix ratios and collagen inter-fibril cross-links are different in wild-type and mutant mice.

  15. Comparison of tibial shaft ski fractures in children and adults.

    PubMed

    Hamada, Tomo; Matsumoto, Kazu; Ishimaru, Daichi; Sumi, Hiroshi; Shimizu, Katsuji

    2014-09-01

    To examine whether child and adult skiers have different risk factors or mechanisms of injury for tibial shaft fractures. Descriptive epidemiological study. Prospectively analyzed the epidemiologic factors, injury types, and injury mechanisms at Sumi Memorial Hospital. This study analyzed information obtained from 276 patients with tibial fractures sustained during skiing between 2004 and 2012. We focused on 174 ski-related tibial shaft fractures with respect to the following factors: age, gender, laterality of fracture, skill level, mechanism of fracture (fall vs collision), scene of injury (steepness of slope), snow condition, and weather. Fracture pattern was graded according to Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification and mechanical direction [external (ER) or internal rotation (IR)]. Tibial shaft fractures were the most common in both children (89.3%) and adults (47.4%). There were no significant differences in gender, side of fracture, mechanism of fracture, snow condition, or weather between children and adults. Skill levels were significantly lower in children than in adults (P < 0.0001). Type A fractures were more dominant in children (73 cases, 72.3%) than in adults (39 cases, 53.4%). There was significantly more ER in children than in adults (P < 0.0001). Among children, female patients had significantly more IR than ER; in contrast, among adults, women were injured by ER. We found significant differences in some of these parameters, suggesting that child and adult skiers have different risk factors or mechanisms of injury for tibial shaft fractures.

  16. Single nickel-related defects in molecular-sized nanodiamonds for multicolor bioimaging: an ab initio study.

    PubMed

    Thiering, Gergő; Londero, Elisa; Gali, Adam

    2014-10-21

    Fluorescent nanodiamonds constitute an outstanding alternative to semiconductor quantum dots and dye molecules for in vivo biomarker applications, where the fluorescence comes from optically active point defects acting as color centers in the nanodiamonds. For practical purposes, these color centers should be photostable as a function of the laser power or the surface termination of nanodiamonds. Furthermore, they should exhibit a sharp and nearly temperature-independent zero-phonon line. In this study, we show by hybrid density functional theory calculations that nickel doped nanodiamonds exhibit the desired properties, thus opening the avenue to practical applications. In particular, harnessing the strong quantum confinement effect in molecule-sized nanodiamonds is very promising for achieving multicolor imaging by single nickel-related defects.

  17. Single nickel-related defects in molecular-sized nanodiamonds for multicolor bioimaging: an ab initio study

    NASA Astrophysics Data System (ADS)

    Thiering, Gergő; Londero, Elisa; Gali, Adam

    2014-09-01

    Fluorescent nanodiamonds constitute an outstanding alternative to semiconductor quantum dots and dye molecules for in vivo biomarker applications, where the fluorescence comes from optically active point defects acting as color centers in the nanodiamonds. For practical purposes, these color centers should be photostable as a function of the laser power or the surface termination of nanodiamonds. Furthermore, they should exhibit a sharp and nearly temperature-independent zero-phonon line. In this study, we show by hybrid density functional theory calculations that nickel doped nanodiamonds exhibit the desired properties, thus opening the avenue to practical applications. In particular, harnessing the strong quantum confinement effect in molecule-sized nanodiamonds is very promising for achieving multicolor imaging by single nickel-related defects.

  18. Long-term complications following tibial plateau levelling osteotomy in small dogs with tibial plateau angles > 30°.

    PubMed

    Knight, Rebekah; Danielski, Alan

    2018-04-21

    Tibial plateau levelling osteotomy (TPLO) is commonly performed for surgical management of cranial cruciate ligament (CCL) disease. It has been suggested that small dogs may have steeper tibial plateau angles (TPAs) than large dogs, which has been associated with increased complication rates after TPLO. A retrospective study was performed to assess the rate and nature of long-term complications following TPLO in small dogs with TPAs>30°. Medical records were reviewed for dogs with TPAs>30° treated for CCL rupture by TPLO with a 2.0 mm plate over a five-year period. Radiographs were assessed to determine TPA, postoperative tibial tuberosity width and to identify any complication. Up-to-date medical records were obtained from the referring veterinary surgeon and any complications in the year after surgery were recorded. The effects of different variables on complication rate were assessed using logistic regression analysis. Minor complications were reported in 22.7 per cent of cases. This is similar to or lower than previously reported complication rates for osteotomy techniques in small dogs and dogs with steep TPAs. A smaller postoperative TPA was the only variable significantly associated with an increased complication rate. No major complications were identified. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. What Components Comprise the Measurement of the Tibial Tuberosity-Trochlear Groove Distance in a Patellar Dislocation Population?

    PubMed

    Tensho, Keiji; Akaoka, Yusuke; Shimodaira, Hiroki; Takanashi, Seiji; Ikegami, Shota; Kato, Hiroyuki; Saito, Naoto

    2015-09-02

    The tibial tuberosity-trochlear groove distance is used as an indicator for medial tibial tubercle transfer; however, to our knowledge, no studies have verified whether this distance is strongly affected by tubercle lateralization at the proximal part of the tibia. We hypothesized that the tibial tuberosity-trochlear groove distance is mainly affected by tibial tubercle lateralization at the proximal part of the tibia. Forty-four patients with a history of patellar dislocation and forty-four age and sex-matched controls were analyzed with use of computed tomography. The tibial tuberosity-trochlear groove distance, tibial tubercle lateralization, trochlear groove medialization, and knee rotation were measured and were compared between the patellar dislocation group and the control group. The association between the tibial tuberosity-trochlear groove distance and three other parameters was calculated with use of the Pearson correlation coefficient and partial correlation analysis. There were significant differences in the tibial tuberosity-trochlear groove distance (p < 0.001) and knee rotation (p < 0.001), but there was no difference in the tibial tubercle lateralization (p = 0.13) and trochlear groove medialization (p = 0.08) between the patellar dislocation group and the control group. The tibial tuberosity-trochlear groove distance had no linear correlation with tubercle lateralization (r = 0.21) or groove medialization (r = -0.15); however, knee rotation had a good positive correlation in the patellar dislocation group (r = 0.62). After adjusting for the remaining parameters, knee rotation strongly correlated with the tibial tuberosity-trochlear groove distance (r = 0.69, p < 0.001), whereas tubercle lateralization showed moderate significant correlations in the patellar dislocation group (r = 0.42; p = 0.005). Because the tibial tuberosity-trochlear groove distance is affected more by knee rotation than by tubercle malposition, its use as an indicator for

  20. Experience with peroneus brevis muscle flaps for reconstruction of distal leg and ankle defects

    PubMed Central

    Bajantri, Babu; Bharathi, Ravindra; Ramkumar, Sanjai; Latheef, Latheesh; Dhane, Smitha; Sabapathy, S. Raja

    2013-01-01

    Objective: Peroneus brevis is a muscle in the leg which is expendable without much functional deficit. The objective of this study was to find out its usefulness in coverage of the defects of the lower leg and ankle. Patients and Methods: A retrospective analysis of the use of 39 pedicled peroneus brevis muscle flaps used for coverage of defects of the lower leg and ankle between November 2010 and December 2012 was carried out. The flaps were proximally based for defects of the lower third of the leg in 12 patients and distally based for reconstruction of defects of the ankle in 26 patients, with one patient having flaps on both ankles. Results: Partial flap loss in critical areas was found in four patients requiring further flap cover and in non-critical areas in two patients, which were managed with a skin graft. Three of the four critical losses occurred when we used it for covering defects over the medial malleolus. There was no complete flap loss in any of the patients. Conclusion: This flap has a unique vascular pattern and fails to fit into the classification of the vasculature of muscles by Mathes and Nahai. The unusual feature is an axial vessel system running down the deep aspect of the muscle and linking the perforators from the peroneal artery and anterior tibial artery, which allows it to be raised proximally or distally on a single perforator. The flap is simple to raise and safe for the reconstruction of small-to moderate-sized skin defects of the distal third of the tibia and all parts of the ankle except the medial malleolus, which is too far from the pedicle of the distally based flap. The donor site can be closed primarily to provide a linear scar. The muscle flap thins with time to provide a good result aesthetically at the primary defect. PMID:23960305

  1. Standing balance in people with trans-tibial amputation due to vascular causes: A literature review.

    PubMed

    Seth, Mayank; Lamberg, Eric

    2017-08-01

    Balance is an important variable to consider during the rehabilitation process of individuals with trans-tibial amputation. Limited evidence exists on the balance abilities of people with trans-tibial amputation due to vascular causes. The purpose of this article is to review literature and determine if standing balance is diminished in people with trans-tibial amputation due to vascular causes. Literature review. Data were obtained from PubMed, Google Scholar, OandP.org , CINHAL, and Science Direct. Studies were selected only if they included standing balance assessment of people with unilateral trans-tibial amputation due to vascular causes. The review yielded seven articles that met the inclusion criteria. The general test methodology required participants to stand still on force platforms, with feet together, while center of pressure or postural sway was recorded. According to the findings of this review, individuals with trans-tibial amputees due to vascular causes have diminished balance abilities. Limited evidence suggests their balance might be further diminished as compared to individuals with trans-tibial amputation due to trauma. Although the evidence is limited, because of the underlying pathology and presence of comorbidities in individuals with trans-tibial amputation due to vascular causes, one cannot ignore these findings, as even a minor injury from a fall may develop into a non-healing ulcer and affect their health and well-being more severely than individuals with trans-tibial amputation due to trauma. Clinical relevance Individuals with trans-tibial amputation due to vascular causes have diminished balance abilities compared to healthy individuals and individuals with trans-tibial amputation due to trauma. This difference should be considered when designing and fabricating prostheses. Prosthetists and rehabilitation clinicians should consider designing amputation cause-specific rehabilitation interventions, focussing on balance and other

  2. Physeal growth arrest after tibial lengthening in achondroplasia: 23 children followed to skeletal maturity.

    PubMed

    Song, Sang-Heon; Agashe, Mandar Vikas; Huh, Young-Jae; Hwang, Soon-Young; Song, Hae-Ryong

    2012-06-01

    Bilateral tibial lengthening has become one of the standard treatments for upper segment-lower segment disproportion and to improve quality of life in achondroplasia. We determined the effect of tibial lengthening on the tibial physis and compared tibial growth that occurred at the physis with that in non-operated patients with achondroplasia. We performed a retrospective analysis of serial radiographs until skeletal maturity in 23 achondroplasia patients who underwent bilateral tibial lengthening before skeletal maturity (lengthening group L) and 12 achondroplasia patients of similar height and age who did not undergo tibial lengthening (control group C). The mean amount of lengthening of tibia in group L was 9.2 cm (lengthening percentage: 60%) and the mean age at the time of lengthening was 8.2 years. The mean duration of follow-up was 9.8 years. Skeletal maturity (fusion of physis) occurred at 15.2 years in group L and at 16.0 years in group C. The actual length of tibia (without distraction) at skeletal maturity was 238 mm in group L and 277 mm in group C (p = 0.03). The mean growth rates showed a decrease in group L relative to group C from about 2 years after surgery. Physeal closure was most pronounced on the anterolateral proximal tibial physis, with relative preservation of the distal physis. Our findings indicate that physeal growth rate can be disturbed after tibial lengthening in achondroplasia, and a close watch should be kept for such an occurrence-especially when lengthening of more than 50% is attempted.

  3. A free vascularized tibia-fibular composite graft for the traumatic femoral bony defect of a 6-year-old boy with 10-year follow up: a case report

    PubMed Central

    2013-01-01

    Introduction Free vascularized fibular grafts have been widely used for the reconstruction of long bone defects. However, the use of a vascularized tibial graft is precluded by its weight-bearing function and unacceptable donor site morbidity. Case presentation We present a rare case of using a vascularized tibia-fibular composite graft taken from a 6-year-old Chinese boy’s ipsilateral lower leg to reconstruct a large bony defect of his traumatic femur. Hypertrophy of the tibial graft, good remodeling of the femoral shaft, and atrophy of the unloaded fibular graft were noted at the 10-year follow up. He was able to participate in outdoor activities such as basketball while wearing his prosthesis. Conclusions The 10-year follow up demonstrates the feasibility of this salvage procedure for a floating knee injury with neurovascular compromise. PMID:23714102

  4. High resolution ultrasonography of the tibial nerve in diabetic peripheral neuropathy.

    PubMed

    Singh, Kunwarpal; Gupta, Kamlesh; Kaur, Sukhdeep

    2017-12-01

    High-resolution ultrasonography of the tibial nerve is a fast and non invasive tool for diagnosis of diabetic peripheral neuropathy. Our study was aimed at finding out the correlation of the cross sectional area and maximum thickness of nerve fascicles of the tibial nerve with the presence and severity of diabetic peripheral neuropathy. 75 patients with type 2 diabetes mellitus clinically diagnosed with diabetic peripheral neuropathy were analysed, and the severity of neuropathy was determined using the Toronto Clinical Neuropathy Score. 58 diabetic patients with no clinical suspicion of diabetic peripheral neuropathy and 75 healthy non-diabetic subjects were taken as controls. The cross sectional area and maximum thickness of nerve fascicles of the tibial nerves were calculated 3 cm cranial to the medial malleolus in both lower limbs. The mean cross sectional area (22.63 +/- 2.66 mm 2 ) and maximum thickness of nerve fascicles (0.70 mm) of the tibial nerves in patients with diabetic peripheral neuropathy compared with both control groups was significantly larger, and statistically significant correlation was found with the Toronto Clinical Neuropathy Score ( p < 0.001). The diabetic patients with no signs of peripheral neuropathy had a larger mean cross sectional area (14.40 +/- 1.72 mm 2 ) and maximum thickness of nerve fascicles of the tibial nerve (0.40 mm) than healthy non-diabetic subjects (12.42 +/- 1.01 mm 2 and 0.30 mm respectively). The cross sectional area and maximum thickness of nerve fascicles of the tibial nerve is larger in diabetic patients with or without peripheral neuropathy than in healthy control subjects, and ultrasonography can be used as a good screening tool in these patients.

  5. Chronic shin splints. Classification and management of medial tibial stress syndrome.

    PubMed

    Detmer, D E

    1986-01-01

    A clinical classification and treatment programme has been developed for chronic medial tibial stress syndrome. Medial tibial stress syndrome has been reported to be either tibial stress fracture or microfracture, tibial periostitis, or distal deep posterior chronic compartment syndrome. Three chronic types exist and may coexist: Type I (tibial microfracture, bone stress reaction or cortical fracture); type II (periostalgia from chronic avulsion of the periosteum at the periosteal-fascial junction); and type III (chronic compartment syndrome syndrome). Type I disease is treated nonoperatively. Operations for resistant types II and III medial tibial stress syndrome were performed in 41 patients. Bilaterality was common (type II, 50% type III, 88%). Seven had coexistent type II/III; one had type I/II. Preoperative symptoms averaged 24 months in type II, 6 months in type III, and 33 months in types II/III. Mean age was 22 years (15 to 51). Resting compartment pressures were normal in type II (mean 12 mm Hg) and elevated in type III and type II/III (mean 23 mm Hg). Type II and type II/III patients received fasciotomy plus periosteal cauterisation. Type III patients had fasciotomy only. All procedures were performed on an outpatient basis using local anaesthesia. Follow up was complete and averaged 6 months (2 to 14 months). Improved performance was as follows: type II, 93%, type III, 100%; type II/III, 86%. Complete cures were as follows: type II, 78%; type III, 75%; and type II/III, 57%. This experience suggests that with precise diagnosis and treatment involving minimal risk and cost the athlete has a reasonable chance of return to full activity.

  6. Comparison of intraoperative anthropometric measurements of the proximal tibia and tibial component in total knee arthroplasty.

    PubMed

    Miyatake, Naohisa; Sugita, Takehiko; Aizawa, Toshimi; Sasaki, Akira; Maeda, Ikuo; Kamimura, Masayuki; Fujisawa, Hirokazu; Takahashi, Atsushi

    2016-09-01

    Precise matching of the tibial component and resected bony surfaces and proper rotational implanting of the tibial component are crucial for successful total knee arthroplasty. We aimed to analyze the exact anthropometric proximal tibial data of Japanese patients undergoing total knee arthroplasty and correlate the measurements with the dimensions of current total knee arthroplasty systems. A total of 703 knees in 566 Japanese patients who underwent total knee arthroplasty for osteoarthritis were included. The bone resection in the proximal tibia was performed perpendicular to the tibial axis in the frontal plane. Measurements of the proximal tibia were intraoperatively obtained after proximal tibial preparation. There were significant positive correlations between the lateral anteroposterior and medial anteroposterior and mediolateral dimensions. A progressive decrease in the mediolateral/lateral anteroposterior ratio with an increasing lateral anteroposterior dimension or the mediolateral/anteroposterior ratio with an increasing anteroposterior dimension was observed. The lateral anteroposterior dimension was smaller than the medial anteroposterior dimension by a mean of 4.8 ± 2.0 mm. The proximal tibia exhibited asymmetry between the lateral and medial plateaus. A comparison of the morphological data and dimensions of the implants, one of which was a symmetric tibial component (NexGen) and the others were asymmetric (Genesis II and Persona), indicated that an asymmetric tibial component could be beneficial to maximize tibial plateau coverage. This study provided important reference data for designing a proper tibial component for Japanese people. The proximal tibial cut surface was asymmetric. There was wide dispersion in the lateral anteroposterior, medial anteroposterior, and mediolateral dimensions depending on the patient. Our data showed that the tibial components of the Genesis II and Persona rather than that of the NexGen may be preferable for

  7. Detection, 3-D positioning, and sizing of small pore defects using digital radiography and tracking

    NASA Astrophysics Data System (ADS)

    Lindgren, Erik

    2014-12-01

    This article presents an algorithm that handles the detection, positioning, and sizing of submillimeter-sized pores in welds using radiographic inspection and tracking. The possibility to detect, position, and size pores which have a low contrast-to-noise ratio increases the value of the nondestructive evaluation of welds by facilitating fatigue life predictions with lower uncertainty. In this article, a multiple hypothesis tracker with an extended Kalman filter is used to track an unknown number of pore indications in a sequence of radiographs as an object is rotated. Each pore is not required to be detected in all radiographs. In addition, in the tracking step, three-dimensional (3-D) positions of pore defects are calculated. To optimize, set up, and pre-evaluate the algorithm, the article explores a design of experimental approach in combination with synthetic radiographs of titanium laser welds containing pore defects. The pre-evaluation on synthetic radiographs at industrially reasonable contrast-to-noise ratios indicate less than 1% false detection rates at high detection rates and less than 0.1 mm of positioning errors for more than 90% of the pores. A comparison between experimental results of the presented algorithm and a computerized tomography reference measurement shows qualitatively good agreement in the 3-D positions of approximately 0.1-mm diameter pores in 5-mm-thick Ti-6242.

  8. Pathomorphism of spiral tibial fractures in computed tomography imaging.

    PubMed

    Guzik, Grzegorz

    2011-01-01

    Spiral fractures of the tibia are virtually homogeneous with regard to their pathomorphism. The differences that are seen concern the level of fracture of the fibula, and, to a lesser extent, the level of fracture of the tibia, the length of fracture cleft, and limb shortening following the trauma. While conventional radiographs provide sufficient information about the pathomorphism of fractures, computed tomography can be useful in demonstrating the spatial arrangement of bone fragments and topography of soft tissues surrounding the fracture site. Multiple cross-sectional computed tomography views of spiral fractures of the tibia show the details of the alignment of bone chips at the fracture site, axis of the tibial fracture cleft, and topography of soft tissues that are not visible on standard radiographs. A model of a spiral tibial fracture reveals periosteal stretching with increasing spiral and longitudinal displacement. The cleft in tibial fractures has a spiral shape and its line is invariable. Every spiral fracture of both crural bones results in extensive damage to the periosteum and may damage bellies of the long flexor muscle of toes, flexor hallucis longus as well as the posterior tibial muscle. Computed tomography images of spiral fractures of the tibia show details of damage that are otherwise invisible on standard radiographs. Moreover, CT images provide useful information about the spatial location of the bone chips as well as possible threats to soft tissues that surround the fracture site. Every spiral fracture of the tibia is associated with disruption of the periosteum. 1. Computed tomography images of spiral fractures of the tibia show details of damage otherwise invisible on standard radiographs, 2. The sharp end of the distal tibial chip can damage the tibialis posterior muscle, long flexor muscles of the toes and the flexor hallucis longus, 3. Every spiral fracture of the tibia is associated with disruption of the periosteum.

  9. Autologous chondrocyte implantation: Is it likely to become a saviour of large-sized and full-thickness cartilage defect in young adult knee?

    PubMed

    Zhang, Chi; Cai, You-Zhi; Lin, Xiang-Jin

    2016-05-01

    A literature review of the first-, second- and third-generation autologous chondrocyte implantation (ACI) technique for the treatment of large-sized (>4 cm(2)) and full-thickness knee cartilage defects in young adults was conducted, examining the current literature on features, clinical scores, complications, magnetic resonance image (MRI) and histological outcomes, rehabilitation and cost-effectiveness. A literature review was carried out in the main medical databases to evaluate the several studies concerning ACI treatment of large-sized and full-thickness knee cartilage defects in young adults. ACI technique has been shown to relieve symptoms and improve functional assessment in large-sized (>4 cm(2)) and full-thickness knee articular cartilage defect of young adults in short- and medium-term follow-up. Besides, low level of evidence demonstrated its efficiency and durability at long-term follow-up after implantation. Furthermore, MRI and histological evaluations provided the evidence that graft can return back to the previous nearly normal cartilage via ACI techniques. Clinical outcomes tend to be similar in different ACI techniques, but with simplified procedure, low complication rate and better graft quality in the third-generation ACI technique. ACI based on the experience of cell-based therapy, with the high potential to regenerate hyaline-like tissue, represents clinical development in treatment of large-sized and full-thickness knee cartilage defects. IV.

  10. Sequential avulsions of the tibial tubercle in an adolescent basketball player.

    PubMed

    Huang, Ying Chieh; Chao, Ying-Hao; Lien, Fang-Chieh

    2010-05-01

    Tibial tubercle avulsion is an uncommon fracture in physically active adolescents. Sequential avulsion of tibial tubercles is extremely rare. We reported a healthy, active 15-year-old boy who suffered from left tibial tubercle avulsion fracture during a basketball game. He received open reduction and internal fixation with two smooth Kirschner wires and a cannulated screw, with every effort to reduce the plate injury. Long-leg splint was used for protection followed by programmed rehabilitation. He recovered uneventfully and returned to his previous level of activity soon. Another avulsion fracture happened at the right tibial tubercle 3.5 months later when he was playing the basketball. From the encouragement of previous successful treatment, we provided him open reduction and fixation with two small-caliber screws. He recovered uneventfully and returned to his previous level of activity soon. No genu recurvatum or other deformity was happening in our case at the end of 2-year follow-up. No evidence of Osgood-Schlatter disease or osteogenesis imperfecta was found. Sequential avulsion fractures of tibial tubercles are rare. Good functional recovery can often be obtained like our case if we treat it well. To a physically active adolescent, we should never overstate the risk of sequential avulsion of the other leg to postpone the return to an active, functional life.

  11. Allogeneic adipose-derived stem cells regenerate bone in a critical-sized ulna segmental defect

    PubMed Central

    Wen, Congji; Yan, Hai; Fu, Shibo; Qian, Yunliang

    2016-01-01

    Adipose-derived stem cells (ASCs) with multilineage potential can be induced into osteoblasts, adipocytes and chondrocytes. ASCs as seed cell are widely used in the field of tissue engineering, but most studies either use autologous cells as the source or an immunodeficient animal as the host. In our present study, we explored the feasibility of applying allogeneic ASCs and demineralized bone matrix (DBM) scaffolds for repairing tubular bone defects without using immunosuppressive therapy. Allogeneic ASCs were expanded and seeded on DBM scaffolds and induced to differentiate along the osteogenic lineage. Eight Sprague–Dawley (SD) rats were used in this study and bilateral critical-sized defects (8 mm) of the ulna were created and divided into two groups: with ASC-DBM constructs or DBM alone. The systemic immune response and the extent of bone healing were evaluated post-operatively. Twenty-four weeks after implantation, digital radiography (DR) testing showed that new bones had formed in the experimental group. By contrast, no bone tissue formation was observed in the control group. This study demonstrated that allogeneic ASCs could promote bone regeneration and repair tubular bone defects combined with DBM by histologically typical bone without systemic immune response PMID:25819682

  12. Management of combined knee medial compartmental and patellofemoral osteoarthritis with lateral closing wedge osteotomy with anterior translation of the distal tibial fragment: Does the degree of anteriorization affect the functional outcome and posterior tibial slope?

    PubMed

    Sadek, Ahmed F; Osman, Mohammed K; Laklok, Mohamed A

    2016-10-01

    The aim of this study was to assess the effect of degree of anterior translation of the distal tibial fragment after lateral closing wedge high tibial osteotomy in patients having combined knee medial compartmental and patellofemoral osteoarthritis. A retrospective study was conducted on 64 patients who were operated on for combined knee medial compartmental and patellofemoral osteoarthritis, by lateral closing wedge high tibial osteotomy with anterior translation of the distal tibial fragment. They were divided into two groups; Group I comprising 32 patients (34 knees, mean age of 51.4±7years) whose degree of anterior translation was <1cm and Group II comprising 32 patients (33 knees, mean age of 52.2±8.3years) whose degree of anterior translation was >1.5cm. The final assessment was performed via: visual analog scale, postoperative Knee Society clinical rating system function score, active range of motion, time to union, degree of correction of mechanical axis, posterior tibial slope, and Insall-Salvati ratio. Group II patients exhibited statistically superior mean postoperative score and better return to their work than Group I (P=0.013, 0.076, respectively). Both groups showed statistically significant differences between the preoperative and postoperative evaluation parameters (P<0.001). The posterior tibial slope was decreased in both groups but with no significant difference (P=0.527). Lateral closing wedge high tibial osteotomy combined with anterior translation of the distal tibial fragment more than 1.5cm achieved significantly better postoperative functional knee score. Both groups exhibited comparatively decreased posterior tibial slope. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Flat midsubstance of the anterior cruciate ligament with tibial "C"-shaped insertion site.

    PubMed

    Siebold, Rainer; Schuhmacher, Peter; Fernandez, Francis; Śmigielski, Robert; Fink, Christian; Brehmer, Axel; Kirsch, Joachim

    2015-11-01

    This anatomical cadaver study was performed to investigate the flat appearance of the midsubstance shape of the anterior cruciate ligament (ACL) and its tibial "C"-shaped insertion site. The ACL midsubstance and the tibial ACL insertion were dissected in 20 cadaveric knees (n = 6 fresh frozen and n = 14 paraffined). Magnifying spectacles were used for all dissections. Morphometric measurements were performed using callipers and on digital photographs. In all specimens, the midsubstance of the ACL was flat with a mean width of 9.9 mm, thickness of 3.9 mm and cross-sectional area of 38.7 mm(2). The "direct" "C"-shaped tibial insertion runs from along the medial tibial spine to the anterior aspect of the lateral meniscus. The mean width (length) of the "C" was 12.6 mm, its thickness 3.3 mm and area 31.4 mm(2). The centre of the "C" was the bony insertion of the anterior root of the lateral meniscus overlayed by fat and crossed by the ACL. No posterolateral (PL) inserting ACL fibres were found. Together with the larger "indirect" part (area 79.6 mm(2)), the "direct" one formed a "duck-foot"-shaped footprint. The tibial ACL midsubstance and tibial "C"-shaped insertion are flat and are resembling a "ribbon". The centre of the "C" is the bony insertion of the anterior root of the lateral meniscus. There are no central or PL inserting ACL fibres. Anatomical ACL reconstruction may therefore require a flat graft and a "C"-shaped tibial footprint reconstruction with an anteromedial bone tunnel for single bundle and an additional posteromedial bone tunnel for double bundle.

  14. Optimization of Soft Tissue Management, Spacer Design, and Grafting Strategies for Large Segmental Bone Defects using the Chronic Caprine Tibial Defect Model

    DTIC Science & Technology

    2016-12-01

    gastrocnemius muscles. 4. Place an interlocking intramedullary nail using a custom spacer to maintain 5-cm defect length. 5. Place a pre-molded 5 cm long x...2 cm diameter PMMA spacer around the nail in the defect. 6. Irrigate the wound with normal (0.9 %) saline and close the wound. The Treatment...PMMA spacer using a “bomb bay door opening”. 4. Remove the spacer without damaging the membrane or nail . 5. Collect appropriate IM samples as

  15. Determination of depth and size of defects in carbon-fiber-reinforced plastic with different methods of pulse thermography

    NASA Astrophysics Data System (ADS)

    Popow, Vitalij; Gurka, Martin

    2018-03-01

    The main advantage of high performance composite material is its exceptional light-weight capability due to individual tailoring of anisotropic fiber lay-up. Its main draw-back is a brittle and complex failure behavior under dynamic loading which requires extensive quality assurance measures and short maintenance intervals. For this reason efficient test methods are required, which not only generate good and reliable results, but are also simple in handling, allow rapid adaptation to different test situations and short measuring times. Especially the knowledge about size and position of a defect is necessary to decide about acceptance or rejection of a structure under investigation. As a promising method for contactless in-line and off-line inspection we used pulsed thermography. For the determination of the depth of the defects we used logarithmic peak second derivative, a widely accepted method. Alternatively an analytical model, describing the adiabatic heating of a solid plate by an instantaneous pulse, was fitted directly to the measurement data. For the determination of defect size four different approaches were investigated and compared with exact values. The measurements were done with continuous carbon-fiber reinforced materials.

  16. Medial tibial pain. A prospective study of its cause among military recruits.

    PubMed

    Milgrom, C; Giladi, M; Stein, M; Kashtan, H; Margulies, J; Chisin, R; Steinberg, R; Swissa, A; Aharonson, Z

    1986-12-01

    In a prospective study of 295 infantry recruits during 14 weeks of basic training, 41% had medial tibial pain. Routine scintigraphic evaluation in cases of medial tibial bone pain showed that 63% had abnormalities. A stress fracture was found in 46%. Only two patients had periostitis. None had ischemic medial compartment syndrome. Physical examination could not differentiate between cases with medial tibial bone pain secondary to stress fractures and those with scintigraphically normal tibias. When both pain and swelling were localized in the middle one-third of the tibia, the lesion most likely proved to be a stress fracture.

  17. [Mobility of a polyethylene tibial insert in a mobile total knee prosthesis].

    PubMed

    Castel, E; Roger, B; Camproux, A; Saillant, G

    1999-03-01

    We have studied the mobility of a mobile tibial implant in total knee arthroplasty (TKA) by a radiographical evaluation. We analyzed mobility of the polyethylene tibial insert of 15 "G2S" TKA implanted for one year or more. We established a dynamic radiographical evaluation. We used 3 weight-bearing radiographs: AP in extension and two lateral (one in extension and one at 90 degrees of flexion), two AP with femoral internal and external rotation, 2 strict lateral X-rays in neutral rotation in antero-posterior replacement with a 25 kilograms strength Telos, and 2 AP in varus and valgus with Telos. Wilcoxon's test and Fisher's exact test were used for statistical evaluation. Our study demonstrated preservation of the polyethylene mobility in tibial TKA implant in all movements: in rotation, in antero-posterior translation with Telos, and even in antero-posterior translation during physiological condition with flexion-extension weight-bearing radiographs. Statistical tests were very significant. We noticed that flexion induced anterior translation of tibial polyethylene when PCL was preserved. This study answered to our question whether mobility of TKA tibial implant persists after implantation. This mobility should reduce loosening forces to the tibia and stress in the polyethylene component. Now we have to determine the amplitude of mobility required to reach this objective.

  18. Improved Healing of Large, Osseous, Segmental Defects by Reverse Dynamization: Evaluation in a Sheep Model

    DTIC Science & Technology

    2014-10-01

    initiated. One such fixator has been tested on a cadaveric sheep tibia. In the unlocked, loose position, the axial stiffness of the tibia and fixator...suggested by our previous studies using rats. This aspect of the project is the present focus of attention, and additional cadaver legs will be tested...characterize external fixators). A 3 mm tibial defect was created in the leg of a cadaveric sheep, and stabilized with an experimental external

  19. Tibial and fibular nerves evaluation using intraoperative electromyography in rats.

    PubMed

    Nepomuceno, André Coelho; Politani, Elisa Landucci; Silva, Eduardo Guandelini da; Salomone, Raquel; Longo, Marco Vinicius Losso; Salles, Alessandra Grassi; Faria, José Carlos Marques de; Gemperli, Rolf

    2016-08-01

    To evaluate a new model of intraoperative electromyographic (EMG) assessment of the tibial and fibular nerves, and its respectives motor units in rats. Eight Wistar rats underwent intraoperative EMG on both hind limbs at two different moments: week 0 and week 12. Supramaximal electrical stimulation applied on sciatic nerve, and compound muscle action potential recorded on the gastrocnemius muscle (GM) and the extensor digitorum longus muscle (EDLM) through electrodes at specifics points. Motor function assessment was performaced through Walking Track Test. Exposing the muscles and nerves for examination did not alter tibial (p=0.918) or fibular (p=0.877) function between the evaluation moments. Electromyography of the GM, innervated by the tibial nerve, revealed similar amplitude (p=0.069) and latency (p=0.256) at week 0 and at 12 weeks, creating a standard of normality. Meanwhile, electromyography of the EDLM, innervated by the fibular nerve, showed significant differences between the amplitudes (p=0.003) and latencies (p=0.021) at the two different moments of observation. Intraoperative electromyography determined and quantified gastrocnemius muscle motor unit integrity, innervated by tibial nerve. Although this study was not useful to, objectively, assess extensor digitorum longus muscle motor unit, innervated by fibular nerve.

  20. Total knee arthroplasty after high tibial osteotomy. A comparison study in patients who had bilateral total knee replacement.

    PubMed

    Meding, J B; Keating, E M; Ritter, M A; Faris, P M

    2000-09-01

    The outcome of total knee replacement after high tibial osteotomy remains uncertain. We hypothesized that the results of total knee replacement with or without a previous high tibial osteotomy are similar. The results of a consecutive series of thirty-nine bilateral total knee arthroplasties performed with cement at an average of 8.7 years after unilateral high tibial osteotomy were reviewed. There were twenty-seven men and twelve women. Preoperatively, the knee scores according to the system of the Knee Society were similar for all of the knees; however, valgus alignment and patella infera were more common in the knees with a previous high tibial osteotomy. Bilateral total knee replacement was staged in seven patients and was simultaneous in thirty-two patients. The results of the total knee arthroplasties were retrospectively reviewed with respect to the knee and function scores according to the system of the Knee Society, the radiographic findings, and the complications. Intraoperatively, no notable differences were identified in the number of medial, lateral, or lateral patellar releases required. However, less lateral tibial bone was resected in the group with a previous high tibial osteotomy (average, 3.3 millimeters) than in the group without a high tibial osteotomy (average, 7.5 millimeters). The average duration of follow-up was 7.5 years (range, three to sixteen years) in the group with a previous high tibial osteotomy and 6.8 years (range, two to ten years) in the group without a high tibial osteotomy. At the time of the final follow-up, the knee and function scores were similar for the two groups (89.0 and 81.0 points, respectively, for the group with a previous high tibial osteotomy, and 89.6 and 83.9 points, respectively, for the group without a high tibial osteotomy). Although more knees were free of pain in the group without a previous high tibial osteotomy (thirty-six) than in the group with a previous osteotomy (thirty-three), this difference was

  1. Management of tibial fractures using a circular external fixator in two calves.

    PubMed

    Aithal, Hari Prasad; Kinjavdekar, Prakash; Amarpal; Pawde, Abhijit Motiram; Singh, Gaj Raj; Setia, Harish Chandra

    2010-07-01

    To report the repair of tibial diaphyseal fractures in 2 calves using a circular external skeletal fixator (CEF). Clinical report. Crossbred calves (n=2; age: 6 months; weight: 55 and 60 kg). Mid-diaphyseal tibial fractures were repaired by the use of a 4-ring CEF (made of aluminum rings with 2 mm K-wires) alone in 1 calf and in combination with hemicerclage wiring in 1 calf. Both calves had good weight bearing with moderate lameness postoperatively. Fracture healing occurred by day 60 in 1 calf and by day 30 in calf 2. The CEF was well maintained and tolerated by both calves through fracture healing. Joint mobility and limb usage improved gradually after CEF removal. CEF provided a stable fixation of tibial fractures and healing within 60 days and functional recovery within 90 days. CEF can be safely and successfully used for the management of selected tibial fractures in calves.

  2. Treatment of segmental tibial fractures with supercutaneous plating.

    PubMed

    He, Xianfeng; Zhang, Jingwei; Li, Ming; Yu, Yihui; Zhu, Limei

    2014-08-01

    Segmental tibial fractures usually follow a high-energy trauma and are often associated with many complications. The purpose of this report is to describe the authors' results in the treatment of segmental tibial fractures with supercutaneous locking plates used as external fixators. Between January 2009 and March 2012, a total of 20 patients underwent external plating (supercutaneous plating) of the segmental tibial fractures using a less-invasive stabilization system locking plate (Synthes, Paoli, Pennsylvania). Six fractures were closed and 14 were open (6 grade IIIa, 2 grade IIIb, 4 grade II, and 2 grade I, according to the Gustilo classification). When imaging studies confirmed bone union, the plates and screws were removed in the outpatient clinic. Average time of follow-up was 23 months (range, 12-47 months). All fractures achieved union. Median time to union was 19 weeks (range, 12-40 weeks) for the proximal fractures and 22 weeks (range, 12-42 weeks) for the distal fractures. Functional results were excellent in 17 patients and good in 3. Delayed union of the fracture occurred in 2 patients. All patients' radiographs showed normal alignment. No rotational deformities and leg shortening were seen. No incidences of deep infection or implant failures occurred. Minor screw tract infection occurred in 2 patients. A new 1-stage protocol using supercutaneous plating as a definitive fixator for segmental tibial fractures is less invasive, has a lower cost, and has a shorter hospitalization time. Surgeons can achieve good reduction, soft tissue reconstruction, stable fixation, and high union rates using supercutaneous plating. The current patients obtained excellent knee and ankle joint motion and good functional outcomes and had a comfortable clinical course. Copyright 2014, SLACK Incorporated.

  3. Tibial rotational osteotomy for idiopathic torsion. A comparison of the proximal and distal osteotomy levels.

    PubMed

    Krengel, W F; Staheli, L T

    1992-10-01

    A retrospective analysis was done of 52 rotational tibial osteotomies (RTOs) performed on 35 patients with severe idiopathic tibial torsion. Thirty-nine osteotomies were performed at the proximal or midtibial level. Thirteen were performed at the distal tibial level with a technique previously described by one of the authors. Serious complications occurred in five (13%) of the proximal and in none of the distal RTOs. For severe and persisting idiopathic tibial torsion, the authors recommend correction by RTO at the distal level. Proximal level osteotomy is indicated only when a varus or valgus deformity required concurrent correction.

  4. The transverse ligament as a landmark for tibial sagittal insertions of the anterior cruciate ligament: a cadaveric study.

    PubMed

    Kongcharoensombat, Wirat; Ochi, Mitsuo; Abouheif, Mohamed; Adachi, Nobuo; Ohkawa, Shingo; Kamei, Goki; Okuhara, Atushi; Shibuya, Hoyatoshi; Niimoto, Takuya; Nakasa, Tomoyuki; Nakamae, Atsuo; Deie, Masataka

    2011-10-01

    The purpose of this study was to determine the relation between the position of the transverse ligament, the anterior edge of the anterior cruciate ligament (ACL) tibial footprint, and the center of the ACL tibial insertion. We used arthroscopy for localization of the anatomic landmarks, followed by insertions of guide pins under direct visualization, and then the position of these guide pins was checked on plain lateral radiographs. The transverse ligament and the anterior aspect of the ACL tibial footprint were identified by arthroscopy in 20 unpaired cadaveric knees (10 left and 10 right). Guide pins were inserted with tibial ACL adapter drill guides under direct observation at the transverse ligament, the anterior aspect of the tibial footprint, and the center of tibial insertion of the ACL. Then, plain lateral radiographs of specimens were taken. The Amis and Jakob line was used to define the attachment of the ACL tibial insertion and the transverse ligament. A sagittal percentage of the location of the insertion point was determined and calculated from the anterior margin of the tibia in the anteroposterior direction. The transverse ligament averaged 21.20% ± 4.1%, the anterior edge of the ACL tibial insertion averaged 21.60% ± 4.0%, and the center of the ACL tibial insertion averaged 40.30% ± 4.8%. There were similar percent variations between the transverse ligament and the anterior edge of the ACL tibial insertion, with no significant difference between them (P = .38). Intraobserver and interobserver reliability was high, with small standard errors of measurement. This study shows that the transverse ligament coincides with the anterior edge of the ACL tibial footprint in the sagittal plane. The transverse ligament can be considered as a new landmark for tibial tunnel positioning during anatomic ACL reconstruction. Copyright © 2011 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  5. Posterior slope of the tibial implant and the outcome of unicompartmental knee arthroplasty.

    PubMed

    Hernigou, Philippe; Deschamps, Gerard

    2004-03-01

    Laboratory studies have suggested that the sagittal displacements permitted by a knee replacement are influenced by the posterior slope of the tibial implant. The effect of the posterior slope of the tibial implant on the outcome of unicompartmental arthroplasty is not well known. The purpose of the present study was to assess the effect of the posterior slope on the long-term outcome of unicompartmental arthroplasty in knees with intact and deficient anterior cruciate ligaments. We retrospectively reviewed the results of ninety-nine unicompartmental arthroplasties after a mean duration of follow-up of sixteen years. At the time of the arthroplasty, the anterior cruciate ligament was considered to be normal in fifty knees, damaged in thirty-one, and absent in eighteen. At the most recent follow-up, we measured the posterior tibial slope and the anterior tibial translation on standing lateral radiographs. The anteroposterior stability of seventy-seven knees that had not been revised by the time of the most recent follow-up was evaluated clinically. In the group of seventy-seven knees that had not been revised by the time of the most recent follow-up, there was a significant linear relationship between anterior tibial translation (mean, 3.7 mm) and posterior tibial slope (mean, 4.3 degrees ) (p < 0.01). The mean posterior slope of the tibial implant was significantly less in the group of seventy-seven knees without loosening of the implant than it was in the group of seventeen knees with loosening of the implant (p < 0.05). Five ruptures of the anterior cruciate ligament occurred in knees in which the ligament had been considered to be normal at the time of implantation; the posterior tibial slope in these five knees was > or = 13 degrees. Clinical evaluation revealed normal or nearly normal anteroposterior stability at the time of the most recent follow-up in all sixty-six unrevised knees in which the anterior cruciate ligament had been present at the time of

  6. Immediate effects of modified landing pattern on a probabilistic tibial stress fracture model in runners.

    PubMed

    Chen, T L; An, W W; Chan, Z Y S; Au, I P H; Zhang, Z H; Cheung, R T H

    2016-03-01

    Tibial stress fracture is a common injury in runners. This condition has been associated with increased impact loading. Since vertical loading rates are related to the landing pattern, many heelstrike runners attempt to modify their footfalls for a lower risk of tibial stress fracture. Such effect of modified landing pattern remains unknown. This study examined the immediate effects of landing pattern modification on the probability of tibial stress fracture. Fourteen experienced heelstrike runners ran on an instrumented treadmill and they were given augmented feedback for landing pattern switch. We measured their running kinematics and kinetics during different landing patterns. Ankle joint contact force and peak tibial strains were estimated using computational models. We used an established mathematical model to determine the effect of landing pattern on stress fracture probability. Heelstrike runners experienced greater impact loading immediately after landing pattern switch (P<0.004). There was an increase in the longitudinal ankle joint contact force when they landed with forefoot (P=0.003). However, there was no significant difference in both peak tibial strains and the risk of tibial stress fracture in runners with different landing patterns (P>0.986). Immediate transitioning of the landing pattern in heelstrike runners may not offer timely protection against tibial stress fracture, despite a reduction of impact loading. Long-term effects of landing pattern switch remains unknown. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. [Free latissimus dorsi flap transfer for reconstruction of soft tissue defects of the lower extremity].

    PubMed

    Knobloch, K; Herold, C; Vogt, P M

    2012-04-01

    Sustainable and durable soft tissue coverage at the lower extremity following trauma, tumor resections, sequelae of radiation therapy or osteomyelitis using free latissimus dorsi muscle transfer is provided by a free latissimus dorsi muscle flap. Soft tissue defects at the lower extremity following trauma, tumor resections, and sequelae of radiation therapy or osteomyelitis. Thoracotomy with incision of the latissimus dorsi muscle; a relative contraindication in wheelchair drivers as well as in overhead athletes due to potential diminished strength and shoulder proprioception following latissimus dorsi muscle transplantation. Under general anesthesia the patient is positioned laterally, and a substantial and meticulous debridement of the defect is performed, as is the identification and preparation of the target vessel, which is preferentially the posterior tibial artery at the calf, or more proximally the popliteal or femoral artery from the medial side as well as concomitant veins/the great saphenous vein. A tailored latissimus dorsi musculocutaneous flap is harvested with subsequent microsurgical anastomosis to the target vessel with preferential end-to-side anastomosis of the artery and end-to-end anastomosis of one or two veins. A 24-h intermediate care unit, clinical flap monitoring for at least 5-7 days, dangling of the flap using an elastic bandage for an initial 3  times  5 min starting on POD 7, compression stockings for at least 6 months subsequently. From 2001-2007 75 free latissimus dorsi flaps were performed (53 ± 17 years) for soft tissue coverage at the lower extremity. In 58% the target vessel was the posterior tibial artery, in 11% the femoral artery, in 8% the anterior tibial artery and in 8% the popliteal artery. In 15% an arteriovenous (AV) loop was applied. Overall free flap survival was 95%. We encountered four total flap losses, exclusively in complex reconstructions with AV-loop situations.

  8. How does tibial cartilage volume relate to symptoms in subjects with knee osteoarthritis?

    PubMed Central

    Wluka, A; Wolfe, R; Stuckey, S; Cicuttini, F

    2004-01-01

    Background: No consistent relationship between the severity of symptoms of knee osteoarthritis (OA) and radiographic change has been demonstrated. Objectives: To determine the relationship between symptoms of knee OA and tibial cartilage volume, whether pain predicts loss of cartilage in knee OA, and whether change in cartilage volume over time relates to change in symptoms over the same period. Method: 132 subjects with symptomatic, early (mild to moderate) knee OA were studied. At baseline and 2 years later, participants had MRI scans of their knee and completed questionnaires quantifying symptoms of knee OA (knee-specific WOMAC: pain, stiffness, function) and general physical and mental health (SF-36). Tibial cartilage volume was determined from the MRI images. Results: Complete data were available for 117 (89%) subjects. A weak association was found between tibial cartilage volume and symptoms at baseline. The severity of the symptoms of knee OA at baseline did not predict subsequent tibial cartilage loss. However, weak associations were seen between worsening of symptoms of OA and increased cartilage loss: pain (rs = 0.28, p = 0.002), stiffness (rs = 0.17, p = 0.07), and deterioration in function (rs = 0.21, p = 0.02). Conclusion: Tibial cartilage volume is weakly associated with symptoms in knee OA. There is a weak association between loss of tibial cartilage and worsening of symptoms. This suggests that although cartilage is not a major determinant of symptoms in knee OA, it does relate to symptoms. PMID:14962960

  9. Prediction of Tibial Rotation Pathologies Using Particle Swarm Optimization and K-Means Algorithms.

    PubMed

    Sari, Murat; Tuna, Can; Akogul, Serkan

    2018-03-28

    The aim of this article is to investigate pathological subjects from a population through different physical factors. To achieve this, particle swarm optimization (PSO) and K-means (KM) clustering algorithms have been combined (PSO-KM). Datasets provided by the literature were divided into three clusters based on age and weight parameters and each one of right tibial external rotation (RTER), right tibial internal rotation (RTIR), left tibial external rotation (LTER), and left tibial internal rotation (LTIR) values were divided into three types as Type 1, Type 2 and Type 3 (Type 2 is non-pathological (normal) and the other two types are pathological (abnormal)), respectively. The rotation values of every subject in any cluster were noted. Then the algorithm was run and the produced values were also considered. The values of the produced algorithm, the PSO-KM, have been compared with the real values. The hybrid PSO-KM algorithm has been very successful on the optimal clustering of the tibial rotation types through the physical criteria. In this investigation, Type 2 (pathological subjects) is of especially high predictability and the PSO-KM algorithm has been very successful as an operation system for clustering and optimizing the tibial motion data assessments. These research findings are expected to be very useful for health providers, such as physiotherapists, orthopedists, and so on, in which this consequence may help clinicians to appropriately designing proper treatment schedules for patients.

  10. Effect of ACL Transection on Internal Tibial Rotation in an in Vitro Simulated Pivot Landing

    PubMed Central

    Oh, Youkeun K.; Kreinbrink, Jennifer L.; Ashton-Miller, James A.; Wojtys, Edward M.

    2011-01-01

    Background: The amount of resistance provided by the ACL (anterior cruciate ligament) to axial tibial rotation remains controversial. The goal of this study was to test the primary hypotheses that ACL transection would not significantly affect tibial rotation under the large impulsive loads associated with a simulated pivot landing but would increase anterior tibial translation. Methods: Twelve cadaveric knees (mean age of donors [and standard deviation] at the time of death, 65.0 ± 10.5 years) were mounted in a custom testing apparatus to simulate a single-leg pivot landing. A compound impulsive load was applied to the distal part of the tibia with compression (∼800 N), flexion moment (∼40 N-m), and axial tibial torque (∼17 N-m) in the presence of five trans-knee muscle forces. A differential variable reluctance transducer mounted on the anteromedial aspect of the ACL measured relative strain. With the knee initially in 15° of flexion, and after five combined compression and flexion moment (baseline) loading trials, six trials were conducted with the addition of either internal or external tibial torque (internal or external loading), and then six baseline trials were performed. The ACL was then sectioned, six baseline trials were repeated, and then six trials of either the internal or the external loading condition, whichever had initially resulted in the larger relative ACL strain, were carried out. Tibiofemoral kinematics were measured optoelectronically. The results were analyzed with a nonparametric Wilcoxon signed-rank test. Results: Following ACL transection, the increase in the normalized internal tibial rotation was significant but small (0.7°/N-m ± 0.3°/N-m to 0.8°/N-m ± 0.3°/N-m, p = 0.012), while anterior tibial translation increased significantly (3.8 ± 2.9 to 7.0 ± 2.9 mm, p = 0.017). Conclusions: ACL transection leads to a small increase in internal tibial rotation, equivalent to a 13% decrease in the dynamic rotational resistance

  11. Delay in weight bearing in surgically treated tibial shaft fractures is associated with impaired healing: a cohort analysis of 166 tibial fractures.

    PubMed

    Houben, I B; Raaben, M; Van Basten Batenburg, M; Blokhuis, T J

    2018-04-09

    The relation between timing of weight bearing after a fracture and the healing outcome is yet to be established, thereby limiting the implementation of a possibly beneficial effect for our patients. The current study was undertaken to determine the effect of timing of weight bearing after a surgically treated tibial shaft fracture. Surgically treated diaphyseal tibial fractures were retrospectively studied between 2007 and 2015. The timing of initial weight bearing (IWB) was analysed as a predictor for impaired healing in a multivariate regression. Totally, 166 diaphyseal tibial fractures were included, 86 cases with impaired healing and 80 with normal healing. The mean age was 38.7 years (range 16-89). The mean time until IWB was significantly shorter in the normal fracture healing group (2.6 vs 7.4 weeks, p < 0.001). Correlation analysis yielded four possible confounders: infection requiring surgical intervention, fracture type, fasciotomy and open fractures. Logistic regression identified IWB as an independent predictor for impaired healing with an odds ratio of 1.13 per week delay (95% CI 1.03-1.25). Delay in initial weight bearing is independently associated with impaired fracture healing in surgically treated tibial shaft fractures. Unlike other factors such as fracture type or soft tissue condition, early resumption of weight bearing can be influenced by the treating physician and this factor therefore has a direct clinical relevance. This study indicates that early resumption of weight bearing should be the treatment goal in fracture fixation. 3b.

  12. Canine stifle joint biomechanics associated with tibial plateau leveling osteotomy predicted by use of a computer model.

    PubMed

    Brown, Nathan P; Bertocci, Gina E; Marcellin-Little, Denis J

    2014-07-01

    To evaluate effects of tibial plateau leveling osteotomy (TPLO) on canine stifle joint biomechanics in a cranial cruciate ligament (CrCL)-deficient stifle joint by use of a 3-D computer model simulating the stance phase of gait and to compare biomechanics in TPLO-managed, CrCL-intact, and CrCL-deficient stifle joints. Computer simulations of the pelvic limb of a Golden Retriever. A previously developed computer model of the canine pelvic limb was used to simulate TPLO stabilization to achieve a tibial plateau angle (TPA) of 5° (baseline value) in a CrCL-deficient stifle joint. Sensitivity analysis was conducted for tibial fragment rotation of 13° to -3°. Ligament loads, relative tibial translation, and relative tibial rotation were determined and compared with values for CrCL-intact and CrCL-deficient stifle joints. TPLO with a 5° TPA converted cranial tibial translation to caudal tibial translation and increased loads placed on the remaining stifle joint ligaments, compared with results for a CrCL-intact stifle joint. Lateral collateral ligament load was similar, medial collateral ligament load increased, and caudal cruciate ligament load decreased after TPLO, compared with loads for a CrCL-deficient stifle joint. Relative tibial rotation after TPLO was similar to that of a CrCL-deficient stifle joint. Stifle joint biomechanics were affected by TPLO fragment rotation. In the model, stifle joint biomechanics were partially improved after TPLO, compared with CrCL-deficient stifle joint biomechanics, but TPLO did not fully restore CrCL-intact stifle joint biomechanics. Overrotation of the tibial fragment negatively influenced stifle joint biomechanics by increasing caudal tibial translation.

  13. Intraoperative study on anthropometry and gender differences of the proximal tibial plateau at the arthroplasty resection surface.

    PubMed

    Yang, Bo; Yu, Jiakuo; Gong, Xi; Chen, Lianxu; Wang, Yongjian; Wang, Jian; Wang, Haijun; Zhang, Jiying

    2014-01-01

    The tibial plateau is asymmetric with a larger medial plateau. We observed from clinical practice that the shape of the tibial plateau does not always present a larger medial plateau. Tibial plateau also showed other shapes. The purpose of this study was to analyze the anthropometric data of the proximal tibia in a large group of Chinese patients undergoing total knee arthroplasty and to investigate the morphology of the resected proximal tibial surface and its gender differences. A total of 822 knees (164 males, 658 females) from the Chinese population were measured intraoperatively for medial anteroposterior (MAP) and lateral anteroposterior (LAP) dimensions of the resected proximal tibial surface. The difference of MAP and LAP (DML) was also calculated as MAP minus LAP. We then classified the data into three groups based on the DML (<-2, -2 to 2, and >2 mm) to analyze the morphology of the proximal tibia and its distribution between male and female. The shape of proximal tibial plateau was of three types: larger medial plateau type, symmetric type, and larger lateral plateau type. There were significant differences between males and females in relation to the shape distribution of the proximal tibial plateau (P < 0.05). Most of the proximal tibial plateau was asymmetric, with 517 of 822 (62.9%) tibia having a DML >2 mm and 120 of 822 (14.6%) tibia having a DML<-2 mm. Only 185 of 822 (22.5%) tibia had a DML between -2 and 2 mm. The results of this study can be used as a guideline to design tibial components with different DMLs to better match the different anthropometry of the resected tibial surface.

  14. Location, location & size: defects close to surfaces dominate fatigue crack initiation

    NASA Astrophysics Data System (ADS)

    Serrano-Munoz, Itziar; Buffiere, Jean-Yves; Mokso, Rajmund; Verdu, Catherine; Nadot, Yves

    2017-03-01

    Metallic cast components inevitably contain defects such as shrinkage cavities which are inherent to the solidification process. Those defects are known to significantly alter the fatigue life of components. Yet very little is known, quantitatively, on the dangerosity of internal casting defects compared to surface ones. In this study, fatigue specimens containing controlled internal defects (shrinkage pores) are used to foster internal cracking. In situ fatigue tests monitored by X ray synchrotron tomography revealed that the internal nucleation and propagation of cracks was systematically overran by surface cracking initiated at castings defects up to ten times smaller than the internal ones. These findings indicate that the presence of internal defects in cast components can be tolerated to a larger extent than is allowed by nowadays standards

  15. Location, location &size: defects close to surfaces dominate fatigue crack initiation.

    PubMed

    Serrano-Munoz, Itziar; Buffiere, Jean-Yves; Mokso, Rajmund; Verdu, Catherine; Nadot, Yves

    2017-03-27

    Metallic cast components inevitably contain defects such as shrinkage cavities which are inherent to the solidification process. Those defects are known to significantly alter the fatigue life of components. Yet very little is known, quantitatively, on the dangerosity of internal casting defects compared to surface ones. In this study, fatigue specimens containing controlled internal defects (shrinkage pores) are used to foster internal cracking. In situ fatigue tests monitored by X ray synchrotron tomography revealed that the internal nucleation and propagation of cracks was systematically overran by surface cracking initiated at castings defects up to ten times smaller than the internal ones. These findings indicate that the presence of internal defects in cast components can be tolerated to a larger extent than is allowed by nowadays standards.

  16. Sheet of osteoblastic cells combined with platelet-rich fibrin improves the formation of bone in critical-size calvarial defects in rabbits.

    PubMed

    Wang, Zhifa; Hu, Hanqing; Li, Zhijin; Weng, Yanming; Dai, Taiqiang; Zong, Chunlin; Liu, Yanpu; Liu, Bin

    2016-04-01

    Techniques that use sheets of cells have been successfully used in various types of tissue regeneration, and platelet-rich fibrin (PRF) can be used as a source of growth factors to promote angiogenesis. We have investigated the effects of the combination of PRF and sheets of mesenchymal stem cells (MSC) from bone marrow on the restoration of bone in critical-size calvarial defects in rabbits to find out whether the combination promotes bony healing. Sheets of MSC and PRF were prepared from the same donor. We then implanted the combined MSC and PRF in critical-size calvarial defects in rabbits and assessed bony restoration by microcomputed tomography (microCT) and histological analysis. The results showed that PRF significantly increased bony regeneration at 8 weeks after implantation of sheets of MSC and PRF compared with sheets of MSC alone (p=0.0048). Our results indicate that the combination of sheets of MSC and PRF increases bone regeneration in critical-size calvarial defects in rabbits, and provides a new way to improve skeletal healing. Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  17. Comparison of the primary stability of different tibial baseplate concepts to retain both cruciate ligaments during total knee arthroplasty.

    PubMed

    Nowakowski, Andrej M; Stangel, Melanie; Grupp, Thomas M; Valderrabano, Victor

    2013-10-01

    A novel tibial baseplate design (Transversal Support Tibial Plateau) as a new treatment concept for bi-cruciate retaining total knee arthroplasty is evaluated for mechanical stability and compared to other tibial baseplate designs. This concept should provide better primary stability and thus, less subsidence, than implantation of two separate unicondylar tibial baseplates. Different baseplates were implanted into synthetic bone specimens (Sawbones® Pacific Research Laboratories, Inc., Washington, USA), all uncemented. Using a standardized experimental setup, subsidence was achieved, enabling comparison of the models regarding primary stability. Overall implant subsidence was significantly increased for the two separate unicondylar tibial baseplates versus the new Transversal Support Tibial Plateau concept, which showed comparable levels to a conventional tibial baseplate. Reduced subsidence results in better primary stability. Linking of two separate baseplates appears to provide increased primary stability in terms of bony fixation, comparable to that of a conventional single tibial baseplate. © 2013. Published by Elsevier Ltd. All rights reserved.

  18. The medial tibial stress syndrome. A cause of shin splints.

    PubMed

    Mubarak, S J; Gould, R N; Lee, Y F; Schmidt, D A; Hargens, A R

    1982-01-01

    The medial tibial stress syndrome is a symptom complex seen in athletes who complain of exercise-induced pain along the distal posterior-medial aspect of the tibia. Intramuscular pressures within the posterior compartments of the leg were measured in 12 patients with this disorder. These pressures were not elevated and therefore this syndrome is a not a compartment syndrome. Available information suggests that the medial tibial stress syndrome most likely represents a periostitis at this location of the leg.

  19. Location, location & size: defects close to surfaces dominate fatigue crack initiation

    PubMed Central

    Serrano-Munoz, Itziar; Buffiere, Jean-Yves; Mokso, Rajmund; Verdu, Catherine; Nadot, Yves

    2017-01-01

    Metallic cast components inevitably contain defects such as shrinkage cavities which are inherent to the solidification process. Those defects are known to significantly alter the fatigue life of components. Yet very little is known, quantitatively, on the dangerosity of internal casting defects compared to surface ones. In this study, fatigue specimens containing controlled internal defects (shrinkage pores) are used to foster internal cracking. In situ fatigue tests monitored by X ray synchrotron tomography revealed that the internal nucleation and propagation of cracks was systematically overran by surface cracking initiated at castings defects up to ten times smaller than the internal ones. These findings indicate that the presence of internal defects in cast components can be tolerated to a larger extent than is allowed by nowadays standards PMID:28345599

  20. Metachronous Bilateral Posterior Tibial Artery Aneurysms in Ehlers-Danlos Syndrome Type IV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hagspiel, Klaus D., E-mail: kdh2n@virginia.edu; Bonatti, Hugo; Sabri, Saher

    2011-04-15

    Ehlers-Danlos syndrome type IV is a life-threatening genetic connective tissue disorder. We report a 24-year-old woman with EDS-IV who presented with metachronous bilateral aneurysms/pseudoaneurysms of the posterior tibial arteries 15 months apart. Both were treated successfully with transarterial coil embolization from a distal posterior tibial approach.

  1. Case report: comprehensive management of medial tibial stress syndrome

    PubMed Central

    Krenner, Bernard John

    2002-01-01

    Abstract Activity or exercise-induced leg pain is a common complication among competitive and “weekend warrior” athletes. Shin splints is a term that has been used to describe all lower leg pain as a result of activity. There are many different causes of “shin splints,” one of which is medial tibial stress syndrome, and the treating clinician must be aware of potentially serious causes of activity related leg pain. Restoring proper biomechanics to the entire kinetic chain and rehabilitation of the injured area should be the primary aim of treatment to optimize shock absorption. The role inflammation plays in medial tibial stress syndrome is controversial, but in this case, seemed to be a causative factor as symptomatology was dramatically decreased with the addition of proteolytic enzymes. Medial tibial stress syndrome can be quite difficult to treat and keeping athletes away from activities that will slow healing or aggravate the condition can be challenging. “Active” rest is the best way in which to allow proper healing while allowing the athlete to maintain their fitness. PMID:19674573

  2. [Influencing factors for trauma-induced tibial infection in underground coal mine].

    PubMed

    Meng, W Z; Guo, Y J; Liu, Z K; Li, Y F; Wang, G Z

    2016-07-20

    Objective: To investigate the influencing factors for trauma-induced tibial infection in underground coal mine. Methods: A retrospective analysis was performed for the clinical data of 1 090 patients with tibial fracture complicated by bone infection who were injured in underground coal mine and admitted to our hospital from January 1995 to August 2015, including the type of trauma, injured parts, severity, and treatment outcome. The association between risk factors and infection was analyzed. Results: Among the 1 090 patients, 357 had the clinical manifestations of acute and chronic bone infection, 219 had red and swollen legs with heat pain, and 138 experienced skin necrosis, rupture, and discharge of pus. The incidence rates of tibial infection from 1995 to 2001, from 2002 to 2008, and from 2009 to 2015 were 31%, 26.9%, and 20.2%, respectively. The incidence rate of bone infection in the proximal segment of the tibia was significantly higher than that in the middle and distal segments (42.1% vs 18.9%/27.1%, P <0.01) . As for patients with different types of trauma (Gustilo typing) , the patients with type III fracture had a significantly higher incidence rate of bone infection than those with type I/II infection (52.8% vs 21.8%/24.6%, P <0.01) . The incidence rates of bone infection after bone traction, internal fixation with steel plates, fixation with external fixator, and fixation with intramedullary nail were 20.7%, 43.5%, 21.4%, and 26.1%, respectively, suggesting that internal fixation with steel plates had a significantly higher incidence rate of bone infection than other fixation methods ( P <0.01) . The multivariate logistic regression analysis showed that the position of tibial fracture and type of fracture were independent risk factors for bone infection. Conclusion: There is a high incidence rate of trauma-induced tibial infection in workers in underground coal mine. The position of tibial fracture and type of fracture are independent risk factors

  3. Magnitude of cement-device interfacial stresses with and without tibial stemming: impact of BMI.

    PubMed

    Gopalakrishnan, Ananthkrishnan; Hedley, Anthony Keith; Kester, Mark A

    2011-03-01

    Patients expect their total knee arthroplasty to relieve pain and to be long lasting. With patients becoming more active, weighing more, and living longer, this expectation becomes increasingly more difficult to fulfill. Patients who are obese and active put greater loads on their implants and may have a greater risk of failure. Although much attention has been paid to decreasing polyethylene wear, a major cause of implant failure, very little research focus has been directed to elucidate other measures to reduce failure, such as the efficacy of prophylactic stemming of the tibial tray. This study explored whether additional mechanical support for tibial base plates would help reduce bone cement stresses in heavy patients, who, like patients with a high activity level, put added stress on their implants. A tibial base plate with a 12-mm-diameter x 50-mm-long stem was compared with the same tibial base plate with a 15-mm-diameter x 20-mm-long end cap using finite element analysis. The results indicate that the tibial base plate with a prophylactic stem significantly reduced compressive and shear stresses on the cement-device interface and therefore may help to reduce the possibility of tibial loosening in these at-risk patients. Further, such studies will aid the surgeon in educating patients and in selecting the appropriate implant strategy.

  4. Minimally-invasive plate osteosynthesis in distal tibial fractures: Results and complications.

    PubMed

    Vidović, Dinko; Matejčić, Aljoša; Ivica, Mihovil; Jurišić, Darko; Elabjer, Esmat; Bakota, Bore

    2015-11-01

    Distal tibial or pilon fractures are usually the result of combined compressive and shear forces, and may result in instability of the metaphysis, with or without articular depression, and injury to the soft tissue. The complexity of injury, lack of muscle cover and poor vascularity make these fractures difficult to treat. Surgical treatment of distal tibial fractures includes several options: external fixation, IM nailing, ORIF and minimally-invasive plate osteosynthesis (MIPO). Management of distal tibial fractures with MIPO enables preservation of soft tissue and remaining blood supply. This is a report of a series of prospectively studied closed distal tibial and pilon fractures treated with MIPO. A total of 21 patients with closed distal tibial or pilon fractures were enrolled in the study between March 2008 and November 2013 and completed follow-up. Demographic characteristics, mechanism of injury, time required for union, ankle range of motion and complications were recorded. Fractures were classified according to the AO/OTA classification. Nineteen patients were initially managed with an ankle-spanning external fixator. When the status of the soft tissue had improved and swelling had subsided enough, a definitive internal fixation with MIPO was performed. Patients were invited for follow-up examinations at 3 and 6 weeks and then at intervals of 6 to 8 weeks until 12 months. Mean age of the patients was 40.1 years (range 19-67 years). Eighteen cases were the result of high-energy trauma and three were the result of low-energy trauma. According to the AO/OTA classification there were extraarticular and intraarticular fractures, but only simple articular patterns without depression or comminution. The average time for fracture union was 19.7 weeks (range 12-38 weeks). Mean range of motion was 10° of dorsiflexion (range 5-15°) and 28.3° of plantar flexion (range 20-35°). Three cases were metalwork-related complications. Two patients underwent plate removal

  5. Polydispersity-driven topological defects as order-restoring excitations.

    PubMed

    Yao, Zhenwei; Olvera de la Cruz, Monica

    2014-04-08

    The engineering of defects in crystalline matter has been extensively exploited to modify the mechanical and electrical properties of many materials. Recent experiments on manipulating extended defects in graphene, for example, show that defects direct the flow of electric charges. The fascinating possibilities offered by defects in two dimensions, known as topological defects, to control material properties provide great motivation to perform fundamental investigations to uncover their role in various systems. Previous studies mostly focus on topological defects in 2D crystals on curved surfaces. On flat geometries, topological defects can be introduced via density inhomogeneities. We investigate here topological defects due to size polydispersity on flat surfaces. Size polydispersity is usually an inevitable feature of a large variety of systems. In this work, simulations show well-organized induced topological defects around an impurity particle of a wrong size. These patterns are not found in systems of identical particles. Our work demonstrates that in polydispersed systems topological defects play the role of restoring order. The simulations show a perfect hexagonal lattice beyond a small defective region around the impurity particle. Elasticity theory has demonstrated an analogy between the elementary topological defects named disclinations to electric charges by associating a charge to a disclination, whose sign depends on the number of its nearest neighbors. Size polydispersity is shown numerically here to be an essential ingredient to understand short-range attractions between like-charge disclinations. Our study suggests that size polydispersity has a promising potential to engineer defects in various systems including nanoparticles and colloidal crystals.

  6. * Composite Biomaterial as a Carrier for Bone-Active Substances for Metaphyseal Tibial Bone Defect Reconstruction in Rats.

    PubMed

    Horstmann, Peter Frederik; Raina, Deepak Bushan; Isaksson, Hanna; Hettwer, Werner; Lidgren, Lars; Petersen, Michael Mørk; Tägil, Magnus

    2017-12-01

    Restoring lost bone is a major challenge in orthopedic surgery. Currently available treatment strategies have shortcomings, such as risk of infection, nonunion, and excessive resorption. Our primary aim was to study if a commercially available gentamicin-containing composite calcium sulfate/hydroxyapatite biomaterial (GBM) could serve as a carrier for local delivery of bone morphogenic protein-2 (BMP-2) and zoledronic acid (ZA) in a tibia defect model in rats. Empty and allograft-filled defects were used as controls. A 3 × 4-mm metaphyseal bone defect was created in the proximal tibia, and the rats were grouped according to defect filling: (1) Empty, (2) Allograft, (3) GBM, (4) GBM + ZA, and (5) GBM + ZA + BMP-2. In vivo microcomputed tomography (micro-CT) images at 4 weeks showed significantly higher mineralized tissue volume (MV) in the intramedullary defect region and the neocortical/callus region in all GBM-treated groups. After euthanization at 8 weeks, ex vivo micro-CT showed that addition of ZA (GBM + ZA) and BMP-2 (GBM + ZA + BMP-2) mainly increased the neocortical and callus formation, with the highest MV in the combined ZA and BMP-2-treated group. Qualitative histological analysis, verifying the increased neocortical/callus thickness and finding of trabecular bone in all GBM-treated groups, supported that the differences in MV measured with micro-CT in fact represented bone tissue. In conclusion, GBM can serve as a carrier for ZA and BMP-2 leading to increased MV in the neocortex and callus of a metaphyseal bone defect in rats.

  7. Outcomes of Surgical Treatment for Anterior Tibial Stress Fractures in Athletes: A Systematic Review.

    PubMed

    Chaudhry, Zaira S; Raikin, Steven M; Harwood, Marc I; Bishop, Meghan E; Ciccotti, Michael G; Hammoud, Sommer

    2017-12-01

    Although most anterior tibial stress fractures heal with nonoperative treatment, some may require surgical management. To our knowledge, no systematic review has been conducted regarding surgical treatment strategies for the management of chronic anterior tibial stress fractures from which general conclusions can be drawn regarding optimal treatment in high-performance athletes. This systematic review was conducted to evaluate the surgical outcomes of anterior tibial stress fractures in high-performance athletes. Systematic review; Level of evidence, 4. In February 2017, a systematic review of the PubMed, MEDLINE, Cochrane, SPORTDiscus, and CINAHL databases was performed to identify studies that reported surgical outcomes for anterior tibial stress fractures. Articles meeting the inclusion criteria were screened, and reported outcome measures were documented. A total of 12 studies, published between 1984 and 2015, reporting outcomes for the surgical treatment of anterior tibial stress fractures were included in this review. All studies were retrospective case series. Collectively, surgical outcomes for 115 patients (74 males; 41 females) with 123 fractures were evaluated in this review. The overall mean follow-up was 23.3 months. The most common surgical treatment method reported in the literature was compression plating (n = 52) followed by drilling (n = 33). Symptom resolution was achieved in 108 of 123 surgically treated fractures (87.8%). There were 32 reports of complications, resulting in an overall complication rate of 27.8%. Subsequent tibial fractures were reported in 8 patients (7.0%). Moreover, a total of 17 patients (14.8%) underwent a subsequent procedure after their initial surgery. Following surgical treatment for anterior tibial stress fracture, 94.7% of patients were able to return to sports. The available literature indicates that surgical treatment of anterior tibial stress fractures is associated with a high rate of symptom resolution and return

  8. Variation in the shape of the tibial insertion site of the anterior cruciate ligament: classification is required.

    PubMed

    Guenther, Daniel; Irarrázaval, Sebastian; Nishizawa, Yuichiro; Vernacchia, Cara; Thorhauer, Eric; Musahl, Volker; Irrgang, James J; Fu, Freddie H

    2017-08-01

    To propose a classification system for the shape of the tibial insertion site (TIS) of the anterior cruciate ligament (ACL) and to demonstrate the intra- and inter-rater agreement of this system. Due to variation in shape and size, different surgical approaches may be feasible to improve reconstruction of the TIS. One hundred patients with a mean age of 26 ± 11 years were included. The ACL was cut arthroscopically at the base of the tibial insertion site. Arthroscopic images were taken from the lateral and medial portal. Images were de-identified and duplicated. Two blinded observers classified the tibial insertion site according to a classification system. The tibial insertion site was classified as type I (elliptical) in 51 knees (51 %), type II (triangular) in 33 knees (33 %) and type III (C-shaped) in 16 knees (16 %). There was good agreement between raters when viewing the insertion site from the lateral portal (κ = 0.65) as well as from the medial portal (κ = 0.66). Intra-rater reliability was good to excellent. Agreement in the description of the insertion site between the medial and lateral portals was good for rater 1 and good for rater 2 (κ = 0.74 and 0.77, respectively). There is variation in the shape of the ACL TIS. The classification system is a repeatable and reliable tool to summarize the shape of the TIS using three common patterns. For clinical relevance, different shapes may require different types of reconstruction to ensure proper footprint restoration. Consideration of the individual TIS shape is required to prevent iatrogenic damage of adjacent structures like the menisci. III.

  9. Nontraumatic tibial polyethylene insert cone fracture in mobile-bearing posterior-stabilized total knee arthroplasty.

    PubMed

    Tanikake, Yohei; Hayashi, Koji; Ogawa, Munehiro; Inagaki, Yusuke; Kawate, Kenji; Tomita, Tetsuya; Tanaka, Yasuhito

    2016-12-01

    A 72-year-old male patient underwent mobile-bearing posterior-stabilized total knee arthroplasty for osteoarthritis. He experienced a nontraumatic polyethylene tibial insert cone fracture 27 months after surgery. Scanning electron microscopy of the fracture surface of the tibial insert cone suggested progress of ductile breaking from the posterior toward the anterior of the cone due to repeated longitudinal bending stress, leading to fatigue breaking at the anterior side of the cone, followed by the tibial insert cone fracture at the anterior side of the cone, resulting in fracture at the base of the cone. This analysis shows the risk of tibial insert cone fracture due to longitudinal stress in mobile-bearing posterior-stabilized total knee arthroplasty in which an insert is designed to highly conform to the femoral component.

  10. Open wedge high tibial osteotomy using three-dimensional printed models: Experimental analysis using porcine bone.

    PubMed

    Kwun, Jun-Dae; Kim, Hee-June; Park, Jaeyoung; Park, Il-Hyung; Kyung, Hee-Soo

    2017-01-01

    The purpose of this study was to evaluate the usefulness of three-dimensional (3D) printed models for open wedge high tibial osteotomy (HTO) in porcine bone. Computed tomography (CT) images were obtained from 10 porcine knees and 3D imaging was planned using the 3D-Slicer program. The osteotomy line was drawn from the three centimeters below the medial tibial plateau to the proximal end of the fibular head. Then the osteotomy gap was opened until the mechanical axis line was 62.5% from the medial border along the width of the tibial plateau, maintaining the posterior tibial slope angle. The wedge-shaped 3D-printed model was designed with the measured angle and osteotomy section and was produced by the 3D printer. The open wedge HTO surgery was reproduced in porcine bone using the 3D-printed model and the osteotomy site was fixed with a plate. Accuracy of osteotomy and posterior tibial slope was evaluated after the osteotomy. The mean mechanical axis line on the tibial plateau was 61.8±1.5% from the medial tibia. There was no statistically significant difference (P=0.160). The planned and post-osteotomy correction wedge angles were 11.5±3.2° and 11.4±3.3°, and the posterior tibial slope angle was 11.2±2.2° pre-osteotomy and 11.4±2.5° post-osteotomy. There were no significant differences (P=0.854 and P=0.429, respectively). This study showed that good results could be obtained in high tibial osteotomy by using 3D printed models of porcine legs. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Ceramic hemi-unicondylar arthroplasty in an adolescent patient with idiopathic tibial chondrolysis.

    PubMed

    Dombroski, Derek; Garino, Jonathan; Lee, Gwo-Chin

    2009-06-01

    Despite recent advances in cartilage regeneration and restoration procedures, isolated, large, full-thickness cartilage lesions in young patients continue to pose significant challenges to patients and orthopedic surgeons. Treatment options for this difficult problem have traditionally included arthrodesis, osteotomy, osteochondral allograft, and prosthetic reconstruction. We present a case of an adolescent patient with isolated idiopathic lateral tibial chondrolysis treated with a custom ceramic hemi-unicondylar hemiarthroplasty. Preoperatively, a 3-dimensional computed tomography scan of the patient's knee was obtained to begin manufacturing a conforming custom ceramic insert that would articulate between the tibial base plate and the patient's native lateral femoral cartilage. Through a lateral parapatellar approach, the tibial preparation was carried out using the Zimmer M/G unicompartmental knee system (Warsaw, Indiana), and the tibial base plate was cemented into position in the standard fashion. A custom, conforming, prefabricated ceramic insert (CeramTec, Memphis, Tennessee) was then inserted onto the tibial base plate. At 5-year follow-up, this salvage procedure was successful in relieving pain and restoring function in this young patient. There were no signs of implant loosening or lysis. Magnetic resonance imaging of the knee at last follow-up revealed that the cartilage thickness of the patient's lateral femoral condyle remained unchanged. Unicondylar hemiarthroplasty performed in patients with large unipolar lesions in the knee can provide durable and reliable pain relief. Ceramic is a viable material that can be considered for articulation with native cartilage.

  12. Effect of tibial tuberosity advancement on femorotibial contact mechanics and stifle kinematics.

    PubMed

    Kim, Stanley E; Pozzi, Antonio; Banks, Scott A; Conrad, Bryan P; Lewis, Daniel D

    2009-01-01

    Objective- To evaluate the effects of tibial tuberosity advancement (TTA) on femorotibial contact mechanics and 3-dimensional kinematics in cranial cruciate ligament (CrCL)-deficient stifles of dogs. Study Design- In vitro biomechanical study. Animals- Unpaired pelvic limbs from 8 dogs, weighing 28-35 kg. Methods- Digital pressure sensors placed subjacent to the menisci were used to measure femorotibial contact force, contact area, peak and mean contact pressure, and peak pressure location with the limb under an axial load of 30% body weight and a stifle angle of 135 degrees . Three-dimensional static poses of the stifle were obtained using a Microscribe digitizing arm. Each specimen was tested under normal, CrCL-deficient, and TTA-treated conditions. Repeated measures analysis of variance with a Tukey post hoc test (P<.05) was used for statistical comparison. Results- Significant disturbances to all measured contact mechanic parameters were evident after CrCL transection, which corresponded to marked cranial tibial subluxation and internal tibial rotation in the CrCL-deficient stifle. No significant differences in any contact mechanic and kinematic parameters were detected between normal and TTA-treated stifles. Conclusion- TTA eliminates craniocaudal stifle instability during simulated weight-bearing and concurrently restores femorotibial contact mechanics to normal. Clinical Relevance- TTA may mitigate the progression of stifle osteoarthritis in dogs afflicted with CrCL insufficiency by eliminating cranial tibial thrust while preserving the normal orientation of the proximal tibial articulating surface.

  13. Biomechanical evaluation of tibial bone adaptation after revision total knee arthroplasty: A comparison of different implant systems

    PubMed Central

    Quilez, María Paz; Seral, Belen; Pérez, María Angeles

    2017-01-01

    The best methods to manage tibial bone defects following total knee arthroplasty remain under debate. Different fixation systems exist to help surgeons reconstruct knee osseous bone loss (such as tantalum cones, cement, modular metal augments, autografts, allografts and porous metaphyseal sleeves) However, the effects of the various solutions on the long-term outcome remain unknown. In the present work, a bone remodeling mathematical model was used to predict bone remodeling after total knee arthroplasty (TKA) revision. Five different types of prostheses were analyzed: one with a straight stem; two with offset stems, with and without supplements; and two with sleeves, with and without stems. Alterations in tibia bone density distribution and implant Von Mises stresses were quantified. In all cases, the bone density decreased in the proximal epiphysis and medullary channels, and an increase in bone density was predicted in the diaphysis and around stem tips. The highest bone resorption was predicted for the offset prosthesis without the supplement, and the highest bone formation was computed for the straight stem. The highest Von Mises stress was obtained for the straight tibial stem, and the lowest was observed for the stemless metaphyseal sleeves prosthesis. The computational model predicted different behaviors among the five systems. We were able to demonstrate the importance of choosing an adequate revision system and that in silico models may help surgeons choose patient-specific treatments. PMID:28886100

  14. Resonance ultrasonic diagnostics of defects in full-size silicon wafers

    NASA Astrophysics Data System (ADS)

    Belyaev, A.; Ostapenko, S.

    2001-12-01

    A resonance acoustic effect was observed recently in full-size 200 mm Cz-Si wafers and applied to characterize as-grown and process-induced defects. Ultrasonic vibrations can be excited into wafers using an external ultrasonic transducer and their amplitude is recorded using a scanning air-coupled acoustic probe operated in a non-contact mode. By sweeping driving frequency, f, of the transducer, we observed an amplification of a specific acoustic mode referred to as ‘whistle’. In this paper, we performed theoretical modeling of the whistle which allowed in attributing this mode to resonant flexural vibrations in a thin circular plate. We calculated normal frequencies of the flexural vibrations of a circular plate of radius ρ in the case of the free edge. The model gives an excellent fit to experimental data with regard to whistle spatial distribution. The results of calculation allow the evaluation of resonance acoustic effect in wafers of different geometries employed in the industry.

  15. Association between foot type and tibial stress injuries: a systematic review.

    PubMed

    Barnes, A; Wheat, J; Milner, C

    2008-02-01

    To systematically review published articles investigating the association between structural foot characteristics and tibial stress injuries, and to suggest possible future avenues of research in this area. Literature was identified, selected and appraised in accordance with the methods of a systematic review. Articles potentially relevant to the research question were identified by searching the following electronic databases: Amed, Cinahl, Index to UK theses, Medline, PubMed, Scopus, Sports discus and Web of science. Duplicates were removed and, based on the title and abstract, the full text of relevant studies were retrieved. Two reviewers independently assessed papers; this formed the basis for the inclusion of the most appropriate trials. From the 479 articles originally identified, nine were deemed appropriate for inclusion in the review. In general, specific data relating to this relationship was limited. Outcomes of the nine investigations were difficult to compare due to differing methods used across studies. Results have proved conflicting, with limited evidence found to implicate any specific foot type as a potential risk factor for tibial stress injuries. No definitive conclusions can be drawn relating foot structure or function to an increased risk of tibial stress injuries. Extremes of foot types are likely to pose an increased risk of tibial stress injuries compared to normal arched feet.

  16. Effect of Tibial Posterior Slope on Knee Kinematics, Quadriceps Force, and Patellofemoral Contact Force After Posterior-Stabilized Total Knee Arthroplasty.

    PubMed

    Okamoto, Shigetoshi; Mizu-uchi, Hideki; Okazaki, Ken; Hamai, Satoshi; Nakahara, Hiroyuki; Iwamoto, Yukihide

    2015-08-01

    We used a musculoskeletal model validated with in vivo data to evaluate the effect of tibial posterior slope on knee kinematics, quadriceps force, and patellofemoral contact force after posterior-stabilized total knee arthroplasty. The maximum quadriceps force and patellofemoral contact force decreased with increasing posterior slope. Anterior sliding of the tibial component and anterior impingement of the anterior aspect of the tibial post were observed with tibial posterior slopes of at least 5° and 10°, respectively. Increased tibial posterior slope contributes to improved exercise efficiency during knee extension, however excessive tibial posterior slope should be avoided to prevent knee instability. Based on our computer simulation we recommend tibial posterior slopes of less than 5° in posterior-stabilized total knee arthroplasty. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. [Investigation of tibial bones of the rats exposed on board "Spacelab-2":histomorphometric analysis

    NASA Technical Reports Server (NTRS)

    Durnova, G. N.; Kaplanskii, A. S.; Morey-Holton, E. R.; Vorobeva, V. N.

    1996-01-01

    Proximal metaphyses of tibial bones from the Sprague-Dowly rats exposed in US dedicated space life sciences laboratory SLS-2 for 13-14 days and sacrificed on day 13 in microgravity and within 5 hours and 14 days following recovery were the subject of histological, histochemical, and histomorphometric analyses. After the 13-day flight of SLS-2 the rats showed initial signs of osteopenia in the spongy tissue of tibial bones, secondary spongiosis affected first. Resorption of the secondary spongiosis was consequent to enhanced resorption and inhibition of osteogenesis. In rats sacrificed within 5 hours of recovery manifestations of tibial osteopenia were more evident than in rats sacrificed during the flight. Spaceflight-induced changes in tibial spongiosis were reverse by character the amount of spongy bone was fully compensated and following 14 days of readaptation to the terrestrial gravity.

  18. The application of porous tantalum cylinder to the repair of comminuted bone defects: a study of rabbit firearm injuries

    PubMed Central

    Ren, Bo; Zhai, Zhenbo; Guo, Kai; Liu, Yanpu; Hou, Weihuan; Zhu, Qingsheng; Zhu, Jinyu

    2015-01-01

    The aim of this study is to investigate the effect of porous tantalum material in repair tibial defects caused by firearm injuries in a rabbit model. A multifunctional biological impact machine was used to establish a rabbit tibial defect model of firearm injury. Porous tantalum rods were processed into a hollow cylinder. Kirschner wires were used for intramedullary fixation. We compared the differences of the bone ingrowth of the porous tantalum material by gross observations, X-rays and histological evaluations. The radiographic observations revealed that fibrous tissue covered the material surface after 4 weeks, and periosteal reactions and new bone callus extending materials appeared after 8 weeks. After 16 weeks, the calluses of the firearm injury group were completely wrapped around a porous tantalum material. The group with the highest Lane-Sandhu X-rays cores was the firearm injury and tantalum implant group, and the blank control group exhibited the lowest scores. The histological evaluations revealed that the presence of new bone around the biomaterial had grown into the porous tantalum. By the 16th week, the areas of bone tissue of the firearm injury group was significant higher than that of non-firearm injury group (P<0.05). The comminuted fractures treated with tantalum cylinders exhibited greater bone ingrowth in the firearm injury group. In conditions of firearm injuries, the porous tantalum biomaterial exhibited bone ingrowth that was beneficial to the treatment of bone defects. PMID:26131078

  19. Choice of Stimulus Range and Size Can Reduce Test-Retest Variability in Glaucomatous Visual Field Defects

    PubMed Central

    Swanson, William H.; Horner, Douglas G.; Dul, Mitchell W.; Malinovsky, Victor E.

    2014-01-01

    Purpose To develop guidelines for engineering perimetric stimuli to reduce test-retest variability in glaucomatous defects. Methods Perimetric testing was performed on one eye for 62 patients with glaucoma and 41 age-similar controls on size III and frequency-doubling perimetry and three custom tests with Gaussian blob and Gabor sinusoid stimuli. Stimulus range was controlled by values for ceiling (maximum sensitivity) and floor (minimum sensitivity). Bland-Altman analysis was used to derive 95% limits of agreement on test and retest, and bootstrap analysis was used to test the hypotheses about peak variability. Results Limits of agreement for the three custom stimuli were similar in width (0.72 to 0.79 log units) and peak variability (0.22 to 0.29 log units) for a stimulus range of 1.7 log units. The width of the limits of agreement for size III decreased from 1.78 to 1.37 to 0.99 log units for stimulus ranges of 3.9, 2.7, and 1.7 log units, respectively (F = 3.23, P < 0.001); peak variability was 0.99, 0.54, and 0.34 log units, respectively (P < 0.01). For a stimulus range of 1.3 log units, limits of agreement were narrowest with Gabor and widest with size III stimuli, and peak variability was lower (P < 0.01) with Gabor (0.18 log units) and frequency-doubling perimetry (0.24 log units) than with size III stimuli (0.38 log units). Conclusions Test-retest variability in glaucomatous visual field defects was substantially reduced by engineering the stimuli. Translational Relevance The guidelines should allow developers to choose from a wide range of stimuli. PMID:25371855

  20. Choice of Stimulus Range and Size Can Reduce Test-Retest Variability in Glaucomatous Visual Field Defects.

    PubMed

    Swanson, William H; Horner, Douglas G; Dul, Mitchell W; Malinovsky, Victor E

    2014-09-01

    To develop guidelines for engineering perimetric stimuli to reduce test-retest variability in glaucomatous defects. Perimetric testing was performed on one eye for 62 patients with glaucoma and 41 age-similar controls on size III and frequency-doubling perimetry and three custom tests with Gaussian blob and Gabor sinusoid stimuli. Stimulus range was controlled by values for ceiling (maximum sensitivity) and floor (minimum sensitivity). Bland-Altman analysis was used to derive 95% limits of agreement on test and retest, and bootstrap analysis was used to test the hypotheses about peak variability. Limits of agreement for the three custom stimuli were similar in width (0.72 to 0.79 log units) and peak variability (0.22 to 0.29 log units) for a stimulus range of 1.7 log units. The width of the limits of agreement for size III decreased from 1.78 to 1.37 to 0.99 log units for stimulus ranges of 3.9, 2.7, and 1.7 log units, respectively ( F = 3.23, P < 0.001); peak variability was 0.99, 0.54, and 0.34 log units, respectively ( P < 0.01). For a stimulus range of 1.3 log units, limits of agreement were narrowest with Gabor and widest with size III stimuli, and peak variability was lower ( P < 0.01) with Gabor (0.18 log units) and frequency-doubling perimetry (0.24 log units) than with size III stimuli (0.38 log units). Test-retest variability in glaucomatous visual field defects was substantially reduced by engineering the stimuli. The guidelines should allow developers to choose from a wide range of stimuli.

  1. Revision 1 size and position of the healthy meniscus, and its correlation with sex, height, weight, and bone area- a cross-sectional study.

    PubMed

    Bloecker, Katja; Englund, Martin; Wirth, Wolfgang; Hudelmaier, Martin; Burgkart, Rainer; Frobell, Richard B; Eckstein, Felix

    2011-10-28

    Meniscus extrusion or hypertrophy may occur in knee osteoarthritis (OA). However, currently no data are available on the position and size of the meniscus in asymptomatic men and women with normal meniscus integrity. Three-dimensional coronal DESSwe MRIs were used to segment and quantitatively measure the size and position of the medial and lateral menisci, and their correlation with sex, height, weight, and tibial plateau area. 102 knees (40 male and 62 female) were drawn from the Osteoarthritis Initiative "non-exposed" reference cohort, including subjects without symptoms, radiographic signs, or risk factors for knee OA. Knees with MRI signs of meniscus lesions were excluded. The tibial plateau area was significantly larger (p < 0.001) in male knees than in female ones (+23% medially; +28% laterally), as was total meniscus surface area (p < 0.001, +20% medially; +26% laterally). Ipsi-compartimental tibial plateau area was more strongly correlated with total meniscus surface area in men (r = .72 medially; r = .62 laterally) and women (r = .67; r = .75) than contra-compartimental or total tibial plateau area, body height or weight. The ratio of meniscus versus tibial plateau area was similar between men and women (p = 0.22 medially; p = 0.72 laterally). Tibial coverage by the meniscus was similar between men and women (50% medially; 58% laterally), but "physiological" medial meniscal extrusion was greater in women (1.83 ± 1.06mm) than in men (1.24mm ± 1.18mm; p = 0.011). These data suggest that meniscus surface area strongly scales with (ipsilateral) tibial plateau area across both sexes, and that tibial coverage by the meniscus is similar between men and women.

  2. Revision 1 Size and position of the healthy meniscus, and its Correlation with sex, height, weight, and bone area- a cross-sectional study

    PubMed Central

    2011-01-01

    Background Meniscus extrusion or hypertrophy may occur in knee osteoarthritis (OA). However, currently no data are available on the position and size of the meniscus in asymptomatic men and women with normal meniscus integrity. Methods Three-dimensional coronal DESSwe MRIs were used to segment and quantitatively measure the size and position of the medial and lateral menisci, and their correlation with sex, height, weight, and tibial plateau area. 102 knees (40 male and 62 female) were drawn from the Osteoarthritis Initiative "non-exposed" reference cohort, including subjects without symptoms, radiographic signs, or risk factors for knee OA. Knees with MRI signs of meniscus lesions were excluded. Results The tibial plateau area was significantly larger (p < 0.001) in male knees than in female ones (+23% medially; +28% laterally), as was total meniscus surface area (p < 0.001, +20% medially; +26% laterally). Ipsi-compartimental tibial plateau area was more strongly correlated with total meniscus surface area in men (r = .72 medially; r = .62 laterally) and women (r = .67; r = .75) than contra-compartimental or total tibial plateau area, body height or weight. The ratio of meniscus versus tibial plateau area was similar between men and women (p = 0.22 medially; p = 0.72 laterally). Tibial coverage by the meniscus was similar between men and women (50% medially; 58% laterally), but "physiological" medial meniscal extrusion was greater in women (1.83 ± 1.06mm) than in men (1.24mm ± 1.18mm; p = 0.011). Conclusions These data suggest that meniscus surface area strongly scales with (ipsilateral) tibial plateau area across both sexes, and that tibial coverage by the meniscus is similar between men and women. PMID:22035074

  3. Acute changes in foot strike pattern and cadence affect running parameters associated with tibial stress fractures.

    PubMed

    Yong, Jennifer R; Silder, Amy; Montgomery, Kate L; Fredericson, Michael; Delp, Scott L

    2018-05-18

    Tibial stress fractures are a common and debilitating injury that occur in distance runners. Runners may be able to decrease tibial stress fracture risk by adopting a running pattern that reduces biomechanical parameters associated with a history of tibial stress fracture. The purpose of this study was to test the hypothesis that converting to a forefoot striking pattern or increasing cadence without focusing on changing foot strike type would reduce injury risk parameters in recreational runners. Running kinematics, ground reaction forces and tibial accelerations were recorded from seventeen healthy, habitual rearfoot striking runners while running in their natural running pattern and after two acute retraining conditions: (1) converting to forefoot striking without focusing on cadence and (2) increasing cadence without focusing on foot strike. We found that converting to forefoot striking decreased two risk factors for tibial stress fracture: average and peak loading rates. Increasing cadence decreased one risk factor: peak hip adduction angle. Our results demonstrate that acute adaptation to forefoot striking reduces different injury risk parameters than acute adaptation to increased cadence and suggest that both modifications may reduce the risk of tibial stress fractures. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Association of physical activity and physical performance with tibial cartilage volume and bone area in young adults.

    PubMed

    Antony, Benny; Venn, Alison; Cicuttini, Flavia; March, Lyn; Blizzard, Leigh; Dwyer, Terence; Cross, Marita; Jones, Graeme; Ding, Changhai

    2015-10-26

    Physical activity has been recommended to patients with knee osteoarthritis for improving their symptoms. However, it is still controversial if physical activity has effects on joint structures including cartilage volume. The aim of this study was to describe the associations between physical activity and performance measured 5 years prior and tibial cartilage volume and bone area in young adults. Subjects broadly representative of the Australian population (n = 328, aged 31-41 years, female 47.3 %) were selected from the Childhood Determinants of Adult Health study. They underwent T1-weighted fat-suppressed magnetic resonance imaging (MRI) scans of their knees. Tibial bone area and cartilage volume were measured from MRI. Physical activity (measured using long international physical activity questionnaire (IPAQ)) and performance measures (long jump, leg muscle strength, physical work capacity (PWC170)) were measured 5 years prior. In multivariable analyses, total physical activity (min/week) (β: 0.30 mm(3), 95 % CI: 0.13,0.47), vigorous (β: 0.54 mm(3), 95 % CI: 0.13,0.94), moderate (β: 0.34 mm(3), 95 % CI: 0.01,0.67), walking (β: 0.40 mm(3), 95 % CI: 0.07,0.72) and IPAQ category (β: 182.9 mm(3), 95 % CI: 51.8,314.0) were positively associated with total tibial cartilage volume but not tibial bone area. PWC170, long jump and leg muscle strength were positively and significantly associated with both total tibial cartilage volume and total tibial bone area; and the associations with tibial cartilage volume decreased in magnitude but remained significant for PWC170 and long jump after further adjustment for tibial bone area. While tibial bone area is affected only by physical performance, total tibial cartilage volume can be influenced by both physical activity and performance in younger adults. The clinical significance suggests a beneficial effect for cartilage but the bone area association was restricted to performance suggesting other factors

  5. Combined sustained release of BMP2 and MMP10 accelerates bone formation and mineralization of calvaria critical size defect in mice.

    PubMed

    Reyes, Ricardo; Rodríguez, Jose Antonio; Orbe, Josune; Arnau, María Rosa; Évora, Carmen; Delgado, Araceli

    2018-11-01

    The effect of dual delivery of bone morphogenetic protein-2 (BMP-2) and matrix metalloproteinase 10 (MMP10) on bone regeneration was investigated in a murine model of calvarial critical-size defect, hypothesizing that it would result in an enhanced bone formation. Critical-size calvarial defects (4 mm diameter) were created in mice and PLGA microspheres preloaded with either BMP-2, MMP10 or a microsphere combination of both were transplanted into defect sites at different doses. Empty microspheres were used as the negative control. Encapsulation efficiency was assessed and in vivo release kinetics of BMP-2 and MMP10 were examined over 14 days. Histological analyses were used to analyze bone formation after four and eight weeks. Combination with MMP10 (30 ng) significantly enhanced BMP-2 (600 ng)-mediated osteogenesis, as confirmed by the increase in percentage of bone fill (p < .05) at four weeks. Moreover, it also increased mineral apposition rate (p < .05), measured by double labeling with tetracycline and calceine. MMP10 accelerates bone repair by enhancing BMP-2-promoted bone healing and improving the mineralization rate. In conclusion combination of MMP10 and BMP-2 may become a promising strategy for repair and regeneration of bone defects.

  6. Radiological Assessment of Bioengineered Bone in a Muscle Flap for the Reconstruction of Critical-Size Mandibular Defect

    PubMed Central

    Al-Fotawei, Randa; Ayoub, Ashraf F.; Heath, Neil; Naudi, Kurt B.; Tanner, K. Elizabeth; Dalby, Matthew J.; McMahon, Jeremy

    2014-01-01

    This study presents a comprehensive radiographic evaluation of bone regeneration within a pedicled muscle flap for the reconstruction of critical size mandibular defect. The surgical defect (20 mm×15 mm) was created in the mandible of ten experimental rabbits. The masseter muscle was adapted to fill the surgical defect, a combination of calcium sulphate/hydroxyapatite cement (CERAMENT™ |SPINE SUPPORT), BMP-7 and rabbit mesenchymal stromal cells (rMSCs) was injected inside the muscle tissue. Radiographic assessment was carried out on the day of surgery and at 4, 8, and 12 weeks postoperatively. At 12 weeks, the animals were sacrificed and cone beam computerized tomography (CBCT) scanning and micro-computed tomography (µ-CT) were carried out. Clinically, a clear layer of bone tissue was identified closely adherent to the border of the surgical defect. Sporadic radio-opaque areas within the surgical defect were detected radiographically. In comparison with the opposite non operated control side, the estimated quantitative scoring of the radio-opacity was 46.6% ±15, the mean volume of the radio-opaque areas was 63.4% ±20. Areas of a bone density higher than that of the mandibular bone (+35% ±25%) were detected at the borders of the surgical defect. The micro-CT analysis revealed thinner trabeculae of the regenerated bone with a more condensed trabecular pattern than the surrounding native bone. These findings suggest a rapid deposition rate of the mineralised tissue and an active remodelling process of the newly regenerated bone within the muscle flap. The novel surgical model of this study has potential clinical application; the assessment of bone regeneration using the presented radiolographic protocol is descriptive and comprehensive. The findings of this research confirm the remarkable potential of local muscle flaps as local bioreactors to induce bone formation for reconstruction of maxillofacial bony defects. PMID:25226170

  7. Does Tibial Slope Affect Perception of Coronal Alignment on a Standing Anteroposterior Radiograph?

    PubMed

    Schwartz, Adam J; Ravi, Bheeshma; Kransdorf, Mark J; Clarke, Henry D

    2017-07-01

    A standing anteroposterior (AP) radiograph is commonly used to evaluate coronal alignment following total knee arthroplasty (TKA). The impact of coronal alignment on TKA outcomes is controversial, perhaps due to variability in imaging and/or measurement technique. We sought to quantify the effect of image rotation and tibial slope on coronal alignment. Using a standard extramedullary tibial alignment guide, 3 cadaver legs were cut to accept a tibial tray at 0°, 3°, and 7° of slope. A computed tomography scan of the entire tibia was obtained for each specimen to confirm neutral coronal alignment. Images were then obtained at progressive 10° intervals of internal and external rotation up to 40° maximum in each direction. Images were then randomized and 5 blinded TKA surgeons were asked to determine coronal alignment. Continuous data values were transformed to categorical data (neutral [0], valgus [L], and varus [R]). Each 10° interval of external rotation of a 7° sloped tibial cut (or relative internal rotation of a tibial component viewed in the AP plane) resulted in perception of an additional 0.75° of varus. The slope of the proximal tibia bone cut should be taken into account when measuring coronal alignment on a standing AP radiograph. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. The location of the tibial accelerometer does influence impact acceleration parameters during running.

    PubMed

    Lucas-Cuevas, Angel Gabriel; Encarnación-Martínez, Alberto; Camacho-García, Andrés; Llana-Belloch, Salvador; Pérez-Soriano, Pedro

    2017-09-01

    Tibial accelerations have been associated with a number of running injuries. However, studies attaching the tibial accelerometer on the proximal section are as numerous as those attaching the accelerometer on the distal section. This study aimed to investigate whether accelerometer location influences acceleration parameters commonly reported in running literature. To fulfil this purpose, 30 athletes ran at 2.22, 2.78 and 3.33 m · s -1 with three accelerometers attached with double-sided tape and tightened to the participants' tolerance on the forehead, the proximal section of the tibia and the distal section of the tibia. Time-domain (peak acceleration, shock attenuation) and frequency-domain parameters (peak frequency, peak power, signal magnitude and shock attenuation in both the low and high frequency ranges) were calculated for each of the tibial locations. The distal accelerometer registered greater tibial acceleration peak and shock attenuation compared to the proximal accelerometer. With respect to the frequency-domain analysis, the distal accelerometer provided greater values of all the low-frequency parameters, whereas no difference was observed for the high-frequency parameters. These findings suggest that the location of the tibial accelerometer does influence the acceleration signal parameters, and thus, researchers should carefully consider the location they choose to place the accelerometer so that equivalent comparisons across studies can be made.

  9. The effect of mesenchymal stem cell sheets on structural allograft healing of critical-sized femoral defects in mice

    PubMed Central

    Long, Teng; Zhu, Zhenan; Awad, Hani A.; Schwarz, Edward M.; Hilton, Matthew J.; Dong, Yufeng

    2014-01-01

    Structural bone allografts are widely used in the clinic to treat critical sized bone defects, despite lacking the osteoinductive characteristics of live autografts. To address this, we generated revitalized structural allografts wrapped with mesenchymal stem/progenitor cell (MSC) sheets, which were produced by expanding primary syngenic bone marrow derived cells on temperature-responsive plates, as a tissue engineered periosteum. In vitro assays demonstrated maintenance of the MSC phenotype in the sheets, suggesting that short-term culturing of MSC sheets is not detrimental. To test their efficacy in vivo, allografts wrapped with MSC sheets were transplanted into 4-mm murine femoral defects and compared to allografts with direct seeding of MSCs and allografts without cells. Evaluations consisted of x-ray plain radiography, 3D microCT, histology, and biomechanical testing at 4- and 6-weeks post-surgery. Our findings demonstrate that MSC sheets induce prolonged cartilage formation at the graft-host junction and enhanced bone callus formation, as well as graft-host osteointegration. Moreover, a large periosteal callus was observed spanning the allografts with MSC sheets, which partially mimics live autograft healing. Finally, biomechanical testing showed a significant increase in the structural and functional properties of MSC sheet grafted femurs. Taken together, MSC sheets exhibit enhanced osteogenicity during critical sized bone defect repair, demonstrating the feasibility of this tissue engineering solution for massive allograft healing. PMID:24393269

  10. Effect of cranial cruciate ligament deficiency, tibial plateau leveling osteotomy, and tibial tuberosity advancement on contact mechanics and alignment of the stifle in flexion.

    PubMed

    Kim, Stanley E; Pozzi, Antonio; Banks, Scott A; Conrad, Bryan P; Lewis, Daniel D

    2010-04-01

    To assess contact mechanics and 3-dimensional (3-D) joint alignment in cranial cruciate ligament (CCL)-deficient stifles before and after tibial plateau leveling osteotomy (TPLO) and tibial tuberosity advancement (TTA) with the stifle in 90 degrees of flexion. In vitro biomechanical study. Cadaveric pelvic limb pairs (n=8) from dogs weighing 28-35 kg. Contralateral limbs were assigned to receive TPLO or TTA. Digital pressure sensors were used to measure femorotibial contact area, peak and mean contact pressure, and peak pressure location with the limb under a load of 30% body weight and stifle flexion angle of 90 degrees . 3-D poses were obtained using a Microscribe digitizer. Specimens were tested under normal, CCL deficient, and treatment conditions. Significant disturbances in alignment were not observed after CCL transection, although medial contact area was 10% smaller than normal (P=.003). There were no significant differences in contact mechanics or alignment between normal and TTA conditions; TPLO induced 6 degrees varus angulation (P<.001), 26% decrease in lateral peak pressure (P=.027), and 18% increase in medial mean pressure (P=.008) when compared with normal. Cranial tibial subluxation is nominal in CCL-deficient stifles loaded in flexion. Stifle alignment and contact mechanics are not altered by TTA, whereas TPLO causes mild varus and a subsequent increase in medial compartment loading. Cranial tibial subluxation of CCL-deficient stifles may not occur during postures that load the stifle in flexion. The significance of minor changes in loading patterns after TPLO is unknown.

  11. A morphologic and quantitative comparison of mechanoreceptors in the tibial remnants of the ruptured human anterior cruciate ligament.

    PubMed

    Sha, Lin; Xie, Guoming; Zhao, Song; Zhao, Jinzhong

    2017-02-01

    Reconstruction of the ruptured anterior cruciate ligament (ACL) does not always result in expected successful outcome. A satisfactory outcome depends not only on the tightness or strength of the graft but also on the quality of proprioceptive restoration. Mechanoreceptors of ACL are supposed to play considerable roles in the proprioceptive feedback system of knee. This study aimed to observe the condition and number of the surviving mechanoreceptors in the tibial remnant of ruptured ACL in human knees.From April 2009 to January 2012, 60 patients with existing free tibial remnants who had undergone arthroscopic ACL reconstruction were enrolled and divided into 4 groups according to the time duration of injury to surgery (Group I: no more than 3 months; Group II: 3 to 6 months; Group III, 6 months to 1 year; Group IV: more than 1 year). Six normal ACL specimens were taken as controls. Specimens were obtained from ACL tibial remnant and stained by the immunohistochemical staining method. The type, size, and quantity of mechanoreceptors were observed under the light microscope. A total of 92 Ruffini-like corpuscles, 9 Pacini-like corpuscles, 5 unclassified neural endings, and free nerve endings were identified via immunohistochemical staining.There were no significant differences in the number of mechanoreceptors in the 5 groups (P = 0.238). Some degenerative changes were observed in Group IV. The results suggest that the residual mechanoreceptors in the ruptured ACL exhibit long-term survival and showed no obvious signs of withering within 1 year.Residual mechanoreceptors do exist in the tibial remnants of ruptured anterior cruciate ligament in human knees and identified clearly by using immunohistochemistry staining. No significant difference was found regarding quantitative variation of the residual mechanoreceptors about the injury duration.

  12. The effect of posterior tibial slope on knee flexion in posterior-stabilized total knee arthroplasty.

    PubMed

    Shi, Xiaojun; Shen, Bin; Kang, Pengde; Yang, Jing; Zhou, Zongke; Pei, Fuxing

    2013-12-01

    To evaluate and quantify the effect of the tibial slope on the postoperative maximal knee flexion and stability in the posterior-stabilized total knee arthroplasty (TKA). Fifty-six patients (65 knees) who had undergone TKA with the posterior-stabilized prostheses were divided into the following 3 groups according to the measured tibial slopes: Group 1: ≤4°, Group 2: 4°-7° and Group 3: >7°. The preoperative range of the motion, the change in the posterior condylar offset, the elevation of the joint line, the postoperative tibiofemoral angle and the preoperative and postoperative Hospital for Special Surgery (HSS) scores were recorded. The tibial anteroposterior translation was measured using the Kneelax 3 Arthrometer at both the 30° and the 90° flexion angles. The mean values of the postoperative maximal knee flexion were 101° (SD 5), 106° (SD 5) and 113° (SD 9) in Groups 1, 2 and 3, respectively. A significant difference was found in the postoperative maximal flexion between the 3 groups (P < 0.001). However, no significant differences were found between the 3 groups in the postoperative HSS scores, the changes in the posterior condylar offset, the elevation of the joint line or the tibial anteroposterior translation at either the 30° or the 90° flexion angles. A 1° increase in the tibial slope resulted in a 1.8° flexion increment (r = 1.8, R (2) = 0.463, P < 0.001). An increase in the posterior tibial slope can significantly increase the postoperative maximal knee flexion. The tibial slope with an appropriate flexion and extension gap balance during the operation does not affect the joint stability.

  13. Bilateral periprosthetic tibial stress fracture after total knee arthroplasty: A case report.

    PubMed

    Ozdemir, Guzelali; Azboy, Ibrahim; Yilmaz, Baris

    2016-01-01

    Periprosthetic fractures around the knee after total knee arthroplasty can be seen in the femur, tibia and patella. The tibial fractures are rare cases. Our case with bilateral tibial stress fracture developed after total knee arthroplasty (TKA) is the first of its kind in the literature. 75-year-old male patient with bilateral knee osteoarthritis had not benefited from conservative treatment methods previously applied. Left TKA was applied. In the second month postoperatively, periprosthetic tibial fracture was identified and osteosynthesis was implemented with locked tibia proximal plate-screw. Bone union in 12 weeks was observed in his follow-ups. After 15 months of his first operation, TKA was applied to the right knee. Postoperatively in the second month, as in the first operation, periprosthetic tibial fracture was detected. Osteosynthesis with locking plate-screw was applied and union in 12 weeks was observed in his follow-up. He was seen mobilized independently and without support in the last control of the case made in the 24th month after the second operation. The number of TKA applications is expected to increase in the future. The incidence of periprosthetic fractures should also be expected to increase in these cases. Periprosthetic tibial fractures after TKA are rarely seen. The treatment of periprosthetic fractures around the knee after TKA can be difficult. In the case of persistent pain in the upper end of the tibia after the surgery, stress fracture should be considered. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Larger medial femoral to tibial condylar dimension may trigger posterior root tear of medial meniscus.

    PubMed

    Chung, Jun Young; Song, Hyung Keun; Jung, Myung Kuk; Oh, Hyeong Tak; Kim, Joon Ho; Yoon, Ji-Sang; Min, Byoung-Hyun

    2016-05-01

    The major meniscal functions are load bearing, load distribution, and shock absorption by increasing the tibiofemoral joint (TFJ) contact area and dissipating axial loads by conversion into hoop stresses. The increased hoop strain stretches the meniscus in outward direction towards radius, causing extrusion, which is associated with the root tear and resultant degenerative osteoarthritis. Since the larger contact area of medial TFJ may increase the hoop stresses, we hypothesized that the larger medial femoral to tibial condylar dimension would contribute to the development of medial meniscus posterior root tear (MMPRT). Thus, the purpose of the study was to assess the relationship between MMPRT and medial femoral to tibial condylar dimension. A case-control study was conducted to compare medial femoral to tibial condylar dimensions of patients with complete MMPRT (n = 59) with those of demography-matched controls (n = 59) during the period from 2010 to 2013. In each patient, MRIs were reviewed and several parameters were measured including articulation width of medial femoral condyle (MFC) at 0°, 30°, 60°, and 90°, medial tibial condyle (MTC) width, degree of meniscal extrusion, and medial femoral to tibial condylar width ratio (MFC/MTC) at 0°, 30°, 60°, and 90°, respectively. Demographic and radiographic data were assessed. A larger medial femoral to tibial condylar dimension was associated with MMPRT at 0° and 30° knee angles. Patients with MFC/MTC greater than 0.9 at 0° also showed about 2.5-fold increase in the chance of MMPRT. Those with meniscal extrusion greater than 3 mm also had about 17.1 times greater chance for the presence of MMPRT accordingly. A larger medial femoral to tibial condylar dimension may be considered as one of the regional contributors to the outbreak of MMPRT, and medial femoral to tibial condylar width ratio greater than 0.9 at 0° knee angle may be considered as a significant risk factor for MMPRT. III.

  15. Optimal lot sizing in screening processes with returnable defective items

    NASA Astrophysics Data System (ADS)

    Vishkaei, Behzad Maleki; Niaki, S. T. A.; Farhangi, Milad; Rashti, Mehdi Ebrahimnezhad Moghadam

    2014-07-01

    This paper is an extension of Hsu and Hsu (Int J Ind Eng Comput 3(5):939-948, 2012) aiming to determine the optimal order quantity of product batches that contain defective items with percentage nonconforming following a known probability density function. The orders are subject to 100 % screening process at a rate higher than the demand rate. Shortage is backordered, and defective items in each ordering cycle are stored in a warehouse to be returned to the supplier when a new order is received. Although the retailer does not sell defective items at a lower price and only trades perfect items (to avoid loss), a higher holding cost incurs to store defective items. Using the renewal-reward theorem, the optimal order and shortage quantities are determined. Some numerical examples are solved at the end to clarify the applicability of the proposed model and to compare the new policy to an existing one. The results show that the new policy provides better expected profit per time.

  16. Posterior tibial nerve stimulation vs parasacral transcutaneous neuromodulation for overactive bladder in children.

    PubMed

    Barroso, Ubirajara; Viterbo, Walter; Bittencourt, Joana; Farias, Tiago; Lordêlo, Patrícia

    2013-08-01

    Parasacral transcutaneous electrical nerve stimulation and posterior tibial nerve stimulation have emerged as effective methods to treat overactive bladder in children. However, to our knowledge no study has compared the 2 methods. We evaluated the results of parasacral transcutaneous electrical nerve stimulation and posterior tibial nerve stimulation in children with overactive bladder. We prospectively studied children with overactive bladder without dysfunctional voiding. Success of treatment was evaluated by visual analogue scale and dysfunctional voiding symptom score, and by level of improvement of each specific symptom. Parasacral transcutaneous electrical nerve stimulation was performed 3 times weekly and posterior tibial nerve stimulation was performed once weekly. A total of 22 consecutive patients were treated with posterior tibial nerve stimulation and 37 with parasacral transcutaneous electrical nerve stimulation. There was no difference between the 2 groups regarding demographic characteristics or types of symptoms. Concerning the evaluation by visual analogue scale, complete resolution of symptoms was seen in 70% of the group undergoing parasacral transcutaneous electrical nerve stimulation and in 9% of the group undergoing posterior tibial nerve stimulation (p = 0.02). When the groups were compared, there was no statistically significant difference (p = 0.55). The frequency of persistence of urgency and diurnal urinary incontinence was nearly double in the group undergoing posterior tibial nerve stimulation. However, this difference was not statistically significant. We found that parasacral transcutaneous electrical nerve stimulation is more effective in resolving overactive bladder symptoms, which matches parental perception. However, there were no statistically significant differences in the evaluation by dysfunctional voiding symptom score, or in complete resolution of urgency or diurnal incontinence. Copyright © 2013 American Urological

  17. Predictors of failure and success of tibial interventions for critical limb ischemia.

    PubMed

    Fernandez, Nathan; McEnaney, Ryan; Marone, Luke K; Rhee, Robert Y; Leers, Steven; Makaroun, Michel; Chaer, Rabih A

    2010-10-01

    The efficacy of tibial artery endovascular intervention (TAEI) for critical limb ischemia (CLI) and particularly for wound healing is not fully defined. The purpose of this study is to determine predictors of failure and success for TAEI in the setting of CLI. All TAEI for tissue loss or rest pain (Rutherford classes 4, 5, and 6) from 2004 to 2008 were retrospectively reviewed. Clinical outcomes and patency rates were analyzed by multivariable Cox proportional hazards regression and life table analysis. One hundred twenty-three limbs in 111 patients (62% male, mean age 74) were treated. Sixty-seven percent of patients were diabetics, 55% had renal insufficiency, and 21% required hemodialysis. One hundred two limbs (83%) exhibited tissue loss; all others had ischemic rest pain. All patients underwent tibial angioplasty (PTA). Tibial excimer laser atherectomy was performed in 14% of the patients. Interventions were performed on multiple tibial vessels in 20% of limbs. Isolated tibial procedures were performed on 50 limbs (41%), while 73 patients had concurrent ipsilateral superficial femoral artery or popliteal interventions. The mean distal popliteal and tibial runoff score improved from 11.8 ± 3.6 to 6.7 ± 1.6 (P < .001), and the mean ankle-brachial index increased from 0.61 ± 0.26 to 0.85 ± 0.22 (P < .001). Surgical bypass was required in seven patients (6%). The mean follow up was 6.8 ± 6.6 months, while the 1-year primary, primary-assisted, and secondary patency rates were 33%, 50%, and 56% respectively. Limb salvage rate at 1 year was 75%. Factors found to be associated with impaired limb salvage included renal insufficiency (hazard ratio [HR] = 5.7; P = .03) and the need for pedal intervention (HR = 13.75; P = .04). TAEI in an isolated peroneal artery (odds ratio = 7.80; P = .01) was associated with impaired wound healing, whereas multilevel intervention (HR = 2.1; P = .009) and tibial laser atherectomy (HR = 3.1; P = .01) were predictors of wound healing

  18. Association between patellar cartilage defects and patellofemoral geometry: a matched-pair MRI comparison of patients with and without isolated patellar cartilage defects.

    PubMed

    Mehl, Julian; Feucht, Matthias J; Bode, Gerrit; Dovi-Akue, David; Südkamp, Norbert P; Niemeyer, Philipp

    2016-03-01

    To compare the geometry of the patellofemoral joint on magnetic resonance images (MRI) between patients with isolated cartilage defects of the patella and a gender- and age-matched control group of patients without patellar cartilage defects. A total of 43 patients (17 female, 26 male) with arthroscopically verified grade III and IV patellar cartilage defects (defect group) were compared with a matched-pair control group of patients with isolated traumatic rupture of the anterior cruciate ligament without cartilage defects of the patellofemoral joint. Preoperative MRI images were analysed retrospectively with regard to patellar geometry (width, thickness, facet angle), trochlear geometry (dysplasia according to Dejour, sulcus angle, sulcus depth, lateral condyle index, trochlea facet asymmetry, lateral trochlea inclination) and patellofemoral alignment (tibial tuberosity-trochlear groove distance, patella height, lateral patella displacement, lateral patellofemoral angle, patella tilt, congruence angle). In addition to the comparison of group values, the measured values were compared to normal values reported in the literature, and the frequency of patients with pathologic findings was compared between both groups. The defect group demonstrated a significantly higher proximal chondral sulcus angle (p < 0.001), a significantly higher distal osseal sulcus angle (p = 0.004), a significantly lower distal sulcus depth (p = 0.047), a significantly lower lateral condyle index (p = 0.045), a significantly lower Caton-Deschamps index (p = 0.020) and a significantly higher Insall-Salvati index (p = 0.010). A major trochlear dysplasia (grade B-D) was significantly more common in the defect group (54 vs. 19%; p < 0.001). Eighty-eight per cent of patients in the defect group demonstrated at least one pathologic finding, compared to 63% in the control group (p = 0.006). Two or more pathologic findings were observed in 42% of the defect group and in 19% of the control group (p

  19. Ipsilateral intact fibula as a predictor of tibial plafond fracture pattern and severity.

    PubMed

    Luk, Pamela C; Charlton, Timothy P; Lee, Jackson; Thordarson, David B

    2013-10-01

    The objective of this study was to determine whether there is a difference in fracture pattern and severity of comminution between tibial plafond fractures with and without associated fibular fractures using computed tomography (CT). We hypothesized that the presence of an intact fibula was predictive of increased tibial plafond fracture severity. This was a case control, radiographic review performed at a single level I university trauma center. Between November 2007 and July 2011, 104 patients with 107 operatively treated tibial pilon fractures and preoperative CT scans were identified: 70 patients with 71 tibial plafond fractures had associated fibular fractures, and 34 patients with 36 tibial plafond fractures had intact fibulas. Four criteria were compared between the 2 groups: AO/OTA classification of distal tibia fractures, Topliss coronal and sagittal fracture pattern classification, plafond region of greatest comminution, and degree of proximal extension of fracture line. The intact fibula group had greater percentages of AO/OTA classification B2 type (5.5 vs 0, P = .046) and B3 type (52.8 vs 28.2, P = .013). Conversely, the percentage of AO/OTA classification C3 type was greater in the fractured fibula group (53.5 vs 30.6, P = .025). Evaluation using the Topliss sagittal and coronal classifications revealed no difference between the 2 groups (P = .226). Central and lateral regions of the plafond were the most common areas of comminution in fractured fibula pilons (32% and 31%, respectively). The lateral region of the plafond was the most common area of comminution in intact fibula pilon fractures (42%). There was no statistically significant difference (P = .71) in degree of proximal extension of fracture line between the 2 groups. Tibial plafond fractures with intact fibulas were more commonly associated with AO/OTA classification B-type patterns, whereas those with fractured fibulas were more commonly associated with C-type patterns. An intact fibula

  20. Posterior tibial vein aneurysm presenting as tarsal tunnel syndrome.

    PubMed

    Ayad, Micheal; Whisenhunt, Anumeha; Hong, EnYaw; Heller, Josh; Salvatore, Dawn; Abai, Babak; DiMuzio, Paul J

    2015-06-01

    Tarsal tunnel syndrome is a compressive neuropathy of the posterior tibial nerve within the tarsal tunnel. Its etiology varies, including space occupying lesions, trauma, inflammation, anatomic deformity, iatrogenic injury, and idiopathic and systemic causes. Herein, we describe a 46-year-old man who presented with left foot pain. Work up revealed a venous aneurysm impinging on the posterior tibial nerve. Following resection of the aneurysm and lysis of the nerve, his symptoms were alleviated. Review of the literature reveals an association between venous disease and tarsal tunnel syndrome; however, this report represents the first case of venous aneurysm causing symptomatic compression of the nerve. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  1. The effect of high tibial osteotomy on osteoarthritis of the knee : Clinical and histological observations.

    PubMed

    Koshino, T; Tsuchiya, K

    1979-03-01

    High tibial osteotomies were performed on 136 osteoarthritic knees for correction of varus deformity. Before osteotomy all patients experienced moderate or severe pain, and the knees showed lateral thrust on weight-bearing. The patients were followed up for one to five years. Marked relief of pain was obtained in 112 knees, and the patients were satisfied with the result of operation in 122. These painless knees showed no lateral thrust, and in the majority the deformity had been adequately corrected, with post-operative femoro-tibial angles (standing) ranging from 165° to 174°. Four of 28 knees with femoro-tibial angles of 175° to 179°, when measured one year after operation, showed recurrence of varus deformity three years after osteotomy. Preoperative ranges of knee motion were well maintained after osteotomy even when arthrotomy had also been undertaken. Intra-articular assessment in two patients, several years after operation, showed that the most degenerated portions of the articular surface were completely covered by a fibrocartilagenous layer, with no bare bone.High tibial osteotomy is most effective in osteoarthritic knees with varus deformity, when correction is made to a femoro-tibial angle (standing) of 170° (10° valgus).

  2. The effect of high tibial osteotomy on osteoarthritis of the knee. Clinical and histological observations.

    PubMed

    Koshino, T; Tsuchiya, K

    1979-01-01

    High tibial osteotomies were performed on 136 osteoarthritic knees for correction of varus deformity. Before osteotomy all patients experienced moderate or severe pain, and the knees showed lateral thrust on weight-bearing. The patients were followed up for one to five years. Marked relief of pain was obtained in 112 knees, and the patients were satisfied with the result of operation in 122. These painless knees showed no lateral thrust, and in the majority the deformity had been adequately corrected, with post-operative femoro-tibial angles (standing) ranging from 165 degrees to 174 degrees. Four of 28 knees with femoro-tibial angles of 175 degrees to 179 degrees, when measured one year after operation, showed recurrence of varus deformity three years after osteotomy. Preoperative ranges of knee motion were well maintained after osteotomy even when arthrotomy had also been undertaken. Intra-articular assessment in two patients, several years after operation, showed that the most degenerated portions of the articular surface were completely covered by a fibrocartilagenous layer, with no bare bone. High tibial osteotomy is most effective in osteoarthritic knees with varus deformity, when correction is made to a femoro-tibial angle (standing) of 170 degrees (10 degrees valgus).

  3. [Operative treatment for complex tibial plateau fractures].

    PubMed

    Song, Qi-Zhi; Li, Tao

    2012-03-01

    To explore the surgical methods and clinical evaluation of complex tibial plateau fractures resulted from high-energy injuries. From March 2006 to May 2009,48 cases with complex tibial plateau fractures were treated with open reduction and plate fixation, including 37 males and 11 females, with an average age of 37 years (ranged from 18 to 63 years). According to Schatzker classification, 16 cases were type IV, 20 cases type V and 12 cases type VI. All patients were examined by X-ray flim and CT scan. The function of knee joint were evaluated according to postoperative follow-up X-ray and Knee Merchant Rating. Forty-eight patients were followed up with a mean time of 14 months. According to Knee Merchant Rating, 24 cases got excellent results, 16 cases good, 6 cases fair and 2 cases poor. Appropriate operation time, anatomical reduction, suitable bone graft and reasonable rehabilitation exercises can maximally recovery the function of knee joint.

  4. Gait retraining and incidence of medial tibial stress syndrome in army recruits.

    PubMed

    Sharma, Jagannath; Weston, Matthew; Batterham, Alan M; Spears, Iain R

    2014-09-01

    Gait retraining, comprising biofeedback and/or an exercise intervention, might reduce the risk of musculoskeletal conditions. The purpose was to examine the effect of a gait-retraining program on medial tibial stress syndrome incidence during a 26-wk basic military training regimen. A total of 450 British Army recruits volunteered. On the basis of a baseline plantar pressure variable (mean foot balance during the first 10% of stance), participants classified as at risk of developing medial tibial stress syndrome (n = 166) were randomly allocated to an intervention (n = 83) or control (n = 83) group. The intervention involved supervised gait retraining, including exercises to increase neuromuscular control and flexibility (three sessions per week) and biofeedback enabling internalization of the foot balance variable (one session per week). Both groups continued with the usual military training regimen. Diagnoses of medial tibial stress syndrome over the 26-wk regimen were made by physicians blinded to the group assignment. Data were modeled in a survival analysis using Cox regression, adjusting for baseline foot balance and time to peak heel rotation. The intervention was associated with a substantially reduced instantaneous relative risk of medial tibial stress syndrome versus control, with an adjusted HR of 0.25 (95% confidence interval, 0.05-0.53). The number needed to treat to observe one additional injury-free recruit in intervention versus control at 20 wk was 14 (11 to 23) participants. Baseline foot balance was a nonspecific predictor of injury, with an HR per 2 SD increment of 5.2 (1.6 to 53.6). The intervention was effective in reducing incidence of medial tibial stress syndrome in an at-risk military sample.

  5. Biomechanical analysis of posteromedial tibial plateau split fracture fixation.

    PubMed

    Zeng, Zhi-Min; Luo, Cong-Feng; Putnis, Sven; Zeng, Bing-Fang

    2011-01-01

    The purpose of this study was to compare the biomechanical strength of four different fixation methods for a posteromedial tibial plateau split fracture. Twenty-eight tibial plateau fractures were simulated using right-sided synthetic tibiae models. Each fracture model was randomly instrumented with one of the four following constructs, anteroposterior lag-screws, an anteromedial limited contact dynamic compression plate (LC-DCP), a lateral locking plate, or a posterior T-shaped buttress plate. Vertical subsidence of the posteromedial fragment was measured from 500 N to 1500 N during biomechanical testing, the maximum load to failure was also determined. It was found that the posterior T-shaped buttress plate allowed the least subsidence of the posteromedial fragment and produced the highest mean failure load than each of the other three constructs (P=0.00). There was no statistical significant difference between using lag screws or an anteromedial LC-DCP construct for the vertical subsidence at a 1500 N load and the load to failure (P>0.05). This study showed that a posterior-based buttress technique is biomechanically the most stable in-vitro fixation method for posteromedial split tibial plateau fractures, with AP screws and anteromedial-based LC-DCP are not as stable for this type of fracture. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Arthroscopic repair of the posterior horn of the medial meniscus with opening wedge high tibial osteotomy: surgical technique.

    PubMed

    Jung, Kwang Am; Kim, Sung Jae; Lee, Su Chan; Jeong, Jae Hoon; Song, Moon Bok; Lee, Choon Key

    2009-07-01

    Simultaneous repair of a radial tear at the tibial attachment site of the posterior horn of the medial meniscus under special circumstances requiring tibial valgus osteotomy is technically difficult. First, most patients who need an osteotomy have a narrowed medial tibiofemoral joint space. In such a situation, the pull-out suture technique is more difficult to perform than in a normal joint space. Second, pulling out suture strands that penetrate the posterior horn of the medial meniscus to the anterior tibial cortex increases the risk of transection during osteotomy. We performed a meniscus repair combined with an opening wedge tibial valgus osteotomy without complications and present our technique as a new method for use in selective cases necessitating both meniscus repair of a complete radial tear and opening wedge tibial osteotomy.

  7. Section modulus is the optimum geometric predictor for stress fractures and medial tibial stress syndrome in both male and female athletes.

    PubMed

    Franklyn, Melanie; Oakes, Barry; Field, Bruce; Wells, Peter; Morgan, David

    2008-06-01

    Various tibial dimensions and geometric parameters have been linked to stress fractures in athletes and military recruits, but many mechanical parameters have still not been investigated. Sedentary people, athletes with medial tibial stress syndrome, and athletes with stress fractures have smaller tibial geometric dimensions and parameters than do uninjured athletes. Cohort study; Level of evidence, 3. Using a total of 88 subjects, male and female patients with either a tibial stress fracture or medial tibial stress syndrome were compared with both uninjured aerobically active controls and uninjured sedentary controls. Tibial scout radiographs and cross-sectional computed tomography images of all subjects were scanned at the junction of the midthird and distal third of the tibia. Tibial dimensions were measured directly from the films; other parameters were calculated numerically. Uninjured exercising men have a greater tibial cortical cross-sectional area than do their sedentary and injured counterparts, resulting in a greater value of some other cross-sectional geometric parameters, particularly the section modulus. However, for women, the cross-sectional areas are either not different or only marginally different, and there are few tibial dimensions or geometric parameters that distinguish the uninjured exercisers from the sedentary and injured subjects. In women, the main difference between the groups was the distribution of cortical bone about the centroid as a result of the different values of section modulus. Last, medial tibial stress syndrome subjects had smaller tibial cross-sectional dimensions than did their uninjured exercising counterparts, suggesting that medial tibial stress syndrome is not just a soft-tissue injury but also a bony injury. The results show that in men, the cross-sectional area and the section modulus are the key parameters in the tibia to distinguish exercise and injury status, whereas for women, it is the section modulus only.

  8. Plate Versus Intramedullary Nail Fixation of Anterior Tibial Stress Fractures: A Biomechanical Study.

    PubMed

    Markolf, Keith L; Cheung, Edward; Joshi, Nirav B; Boguszewski, Daniel V; Petrigliano, Frank A; McAllister, David R

    2016-06-01

    Anterior midtibial stress fractures are an important clinical problem for patients engaged in high-intensity military activities or athletic training activities. When nonoperative treatment has failed, intramedullary (IM) nail and plate fixation are 2 surgical options used to arrest the progression of a fatigue fracture and allow bone healing. A plate will be more effective than an IM nail in preventing the opening of a simulated anterior midtibial stress fracture from tibial bending. Controlled laboratory study. Fresh-frozen human tibias were loaded by applying a pure bending moment in the sagittal plane. Thin transverse saw cuts, 50% and 75% of the depth of the anterior tibial cortex, were created at the midtibia to simulate a fatigue fracture. An extensometer spanning the defect was used to measure the fracture opening displacement (FOD) before and after the application of IM nail and plate fixation constructs. IM nails were tested without locking screws, with a proximal screw only, and with proximal and distal screws. Plates were tested with unlocked bicortical screws (standard compression plate) and locked bicortical screws; both plate constructs were tested with the plate edge placed 1 mm from the anterior tibial crest (anterior location) and 5 mm posterior to the crest. For the 75% saw cut depth, the mean FOD values for all IM nail constructs were 13% to 17% less than those for the saw cut alone; the use of locking screws had no significant effect on the FOD. The mean FOD values for all plate constructs were significantly less than those for all IM nail constructs. The mean FOD values for all plates were 28% to 46% less than those for the saw cut alone. Anterior plate placement significantly decreased mean FOD values for both compression and locked plate constructs, but the mean percentage reductions for locked and unlocked plates were not significantly different from each other for either plate placement. The percentage FOD reductions for all plate

  9. The effect of mesenchymal stem cell sheets on structural allograft healing of critical sized femoral defects in mice.

    PubMed

    Long, Teng; Zhu, Zhenan; Awad, Hani A; Schwarz, Edward M; Hilton, Matthew J; Dong, Yufeng

    2014-03-01

    Structural bone allografts are widely used in the clinic to treat critical sized bone defects, despite lacking the osteoinductive characteristics of live autografts. To address this, we generated revitalized structural allografts wrapped with mesenchymal stem/progenitor cell (MSC) sheets, which were produced by expanding primary syngenic bone marrow derived cells on temperature-responsive plates, as a tissue-engineered periosteum. In vitro assays demonstrated maintenance of the MSC phenotype in the sheets, suggesting that short-term culturing of MSC sheets is not detrimental. To test their efficacy in vivo, allografts wrapped with MSC sheets were transplanted into 4-mm murine femoral defects and compared to allografts with direct seeding of MSCs and allografts without cells. Evaluations consisted of X-ray plain radiography, 3D microCT, histology, and biomechanical testing at 4- and 6-weeks post-surgery. Our findings demonstrate that MSC sheets induce prolonged cartilage formation at the graft-host junction and enhanced bone callus formation, as well as graft-host osteointegration. Moreover, a large periosteal callus was observed spanning the allografts with MSC sheets, which partially mimics live autograft healing. Finally, biomechanical testing showed a significant increase in the structural and functional properties of MSC sheet grafted femurs. Taken together, MSC sheets exhibit enhanced osteogenicity during critical sized bone defect repair, demonstrating the feasibility of this tissue engineering solution for massive allograft healing. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. A new design of facial artery perforator flaps for the reconstruction of small- to medium-sized intraoral defects.

    PubMed

    Du, Yi-fei; Zhou, Wei-na; Li, Jie; Jiang, Hong-bing; Yuan, Hua; Wan, Lin-zhong

    2014-11-01

    The aim of this study was to investigate the reliability and outcomes of a new design of facial artery perforator flaps, extending from the angle of the mouth to the border of the mandible, for the reconstruction of small- to medium-sized intraoral defects. The technique had been used in 23 patients between February 2009 and August 2012. The locations of intraoral defects included the tongue, the floor of the mouth, the inferior gingival mucosa, and the sublingual gland. All flaps were monitored for complications including skin loss and ischemia. The functions of appearance, swallowing, and speech were assessed 6 months after operation with the University of Washington Quality of Life Questionnaire. All flaps presented with satisfactory results except for one, which demonstrated superficial tip necrosis that settled after conservative treatment. The follow-up period ranged from 6 to 12 months, and 1 patient died as a result of pulmonary metastasis, and 3 patients underwent second surgery because of local tumor recurrence (2patients) and cervical recurrence (1 patient). Nineteen patients were assessed with the University of Washington Quality of Life Questionnaire, and the mean (SD) scores of appearance, swallowing, and speech were 57.89 (14.45), 83.68 (19.98), and 81.58 (23.16), respectively. This design of facial artery perforator flaps could provide an efficient and cost-effective method for reconstruction of small- to medium-sized intraoral defects with a low surgical morbidity and satisfactory levels of quality of life.

  11. Evaluation of photobiomodulation therapy associated with guided bone regeneration in critical size defects. In vivo study.

    PubMed

    Freitas, Nicole Rosa de; Guerrini, Luísa Belluco; Esper, Luis Augusto; Sbrana, Michyele Cristhiane; Dalben, Gisele da Silva; Soares, Simone; Almeida, Ana Lúcia Pompéia Fraga de

    2018-01-01

    The repair of bone defects raises the interest of investigators in several health specialties. Grafting techniques with bone substitutes and laser therapies have been investigated to replace autogenous bone and accelerate the bone healing process. Objective To evaluate the effect of photobiomodulation therapy (PBMT) associated with guided bone regeneration (GBR) in critical size defects. Material and Methods The study was conducted on 80 male rats (Rattus norvegicus albinus, Wistar) submitted to surgical creation of a critical size defect on the calvaria, divided into eight study groups: group C (control - only blood clot); group M (collagen membrane); group PBMT (photobiomodulation therapy); group AB (autogenous bone); group AB+PBMT; group AB+M; group PBMT+M; group AB+PBMT+M. The animals were killed 30 days postoperatively. After tissue processing, bone regeneration was evaluated by histomorphometric analysis and statistical analyses were performed (Tukey test, p<0.05). Results All groups had greater area of newly formed bone compared to group C (9.96±4.49%). The group PBMT+M (achieved the greater quantity of new bone (64.09±7.62%), followed by groups PBMT (47.67±8.66%), M (47.43±15.73%), AB+PBMT (39.15±16.72%) and AB+PBMT+M (35.82±7.68%). After group C, the groups AB (25.10±16.59%) and AB+M (22.72±13.83%) had the smallest quantities of newly formed bone. The area of remaining particles did not have statistically significant difference between groups AB+M (14.93±8.92%) and AB+PBMT+M (14.76±6.58%). Conclusion The PBMT utilization may be effective for bone repair, when associated with bone regeneration techniques.

  12. Tibial anatomy in normal small breed dogs including anisometry of various extracapsular stabilizing suture attachment sites.

    PubMed

    Witte, P G

    2015-01-01

    To investigate proximal tibial anatomy and its influence on anisometry of extracapsular stabilizing sutures in small dog breeds. Mediolateral radiographs of the femora, stifles, and tibiae of 12 small breed dogs were acquired with the stifles positioned at various angles. Measurements taken included tibial plateau angle (TPA), diaphyseal: proximal tibial angle (DPA), patellar tendon angle (PTA), Z-angle, relative tibial tuberosity width (rTTW), and the distance between six combinations of two femoral and three tibial extra-capsular stabilizing suture (ECS) attachment sites. Theoretical strain through stifle range-of-motion was recorded. The TPA (32° ± 5.8°), DPA (10.2° ± 7.3°), PTA (103.7° ± 6.2°), and Z-angle (70.4° ± 9.0°) were positively correlated with one another (R >0.7), but none were correlated with rTTW (0.93 ± 0.10). The F2-T1 combination of ECS attachment sites had lowest strain for nine stifles. The shortest attachment site separation was at a stifle flexion of 50° for nine stifles. Proximal tibial anatomy measurements could not predict optimal attachment site combination, optimal stifle angle for suture placement, or ECS strain. There is individual variation in the optimal attachment site combination and stifle angle for suture placement, which may influence consistency of outcomes with ECS.

  13. ACL Roof Impingement Revisited: Does the Independent Femoral Drilling Technique Avoid Roof Impingement With Anteriorly Placed Tibial Tunnels?

    PubMed

    Tanksley, John A; Werner, Brian C; Conte, Evan J; Lustenberger, David P; Burrus, M Tyrrell; Brockmeier, Stephen F; Gwathmey, F Winston; Miller, Mark D

    2017-05-01

    Anatomic femoral tunnel placement for single-bundle anterior cruciate ligament (ACL) reconstruction is now well accepted. The ideal location for the tibial tunnel has not been studied extensively, although some biomechanical and clinical studies suggest that placement of the tibial tunnel in the anterior part of the ACL tibial attachment site may be desirable. However, the concern for intercondylar roof impingement has tempered enthusiasm for anterior tibial tunnel placement. To compare the potential for intercondylar roof impingement of ACL grafts with anteriorly positioned tibial tunnels after either transtibial (TT) or independent femoral (IF) tunnel drilling. Controlled laboratory study. Twelve fresh-frozen cadaver knees were randomized to either a TT or IF drilling technique. Tibial guide pins were drilled in the anterior third of the native ACL tibial attachment site after debridement. All efforts were made to drill the femoral tunnel anatomically in the center of the attachment site, and the surrogate ACL graft was visualized using 3-dimensional computed tomography. Reformatting was used to evaluate for roof impingement. Tunnel dimensions, knee flexion angles, and intra-articular sagittal graft angles were also measured. The Impingement Review Index (IRI) was used to evaluate for graft impingement. Two grafts (2/6, 33.3%) in the TT group impinged upon the intercondylar roof and demonstrated angular deformity (IRI type 1). No grafts in the IF group impinged, although 2 of 6 (66.7%) IF grafts touched the roof without deformation (IRI type 2). The presence or absence of impingement was not statistically significant. The mean sagittal tibial tunnel guide pin position prior to drilling was 27.6% of the sagittal diameter of the tibia (range, 22%-33.9%). However, computed tomography performed postdrilling detected substantial posterior enlargement in 2 TT specimens. A significant difference in the sagittal graft angle was noted between the 2 groups. TT grafts were

  14. Reliability of frames of reference used for tibial component rotation in total knee arthroplasty.

    PubMed

    Page, Stephen R; Deakin, Angela H; Payne, Anthony P; Picard, Frederic

    2011-01-01

    This study evaluated seven different frames of reference used for tibial component rotation in total knee arthroplasty (TKA) to determine which ones showed good reliability between bone specimens. An optoelectronic system based around a computer-assisted surgical navigation system was used to measure and locate 34 individual anatomical landmarks on 40 tibias. Each particular frame of reference was reconstructed from a group of data points taken from the surface of each bone. The transverse axis was used as the baseline to which the other axes were compared, and the differences in angular rotation between the other six reference frames and the transverse axis were calculated. There was high variability in the tibial rotational alignment associated with all frames of reference. Of the references widely used in current TKA procedures, the tibial tuberosity axis and the anterior condylar axis had lower standard deviations (6.1° and 7.3°, respectively) than the transmalleolar axis and the posterior condylar axis (9.3° for both). In conclusion, we found high variability in the frames of reference used for tibial rotation alignment. However, the anterior condylar axis and transverse axis may warrant further tests with the use of navigation. Combining different frames of reference such as the tibial tuberosity axis, anterior condylar axis and transverse axis may reduce the range of errors found in all of these measurements.

  15. Knee braces can decrease tibial rotation during pivoting that occurs in high demanding activities.

    PubMed

    Giotis, Dimitrios; Tsiaras, Vasilios; Ristanis, Stavros; Zampeli, Franceska; Mitsionis, Grigoris; Stergiou, Nicholas; Georgoulis, Anastasios D

    2011-08-01

    The purpose of this study was to investigate whether knee braces could effectively decrease tibial rotation during high demanding activities. Using an in vivo three-dimensional kinematic analysis, 21 physically active, healthy, male subjects were evaluated. Each subject performed two tasks that were used extensively in the literature because they combine increased rotational and translational loads on the knee, (1) descending from a stair and subsequent pivoting and (2) landing from a platform and subsequent pivoting under three conditions: (A) wearing a prophylactic brace (braced), (B) wearing a patellofemoral brace (sleeved), and (C) unbraced condition. In the first task, tibial rotation during the pivoting phase was significantly decreased in the braced condition as compared to the sleeved condition (P = 0.019) and the non-braced condition (P = 0.002). In the second task, the same variable was significantly decreased in the braced condition as compared to the sleeved (P = 0.001) and the unbraced condition (P < 0.001). The sleeved condition also produced significantly decreased tibial rotation with respect to the unbraced condition (P = 0.021). Bracing decreased tibial rotation in activities where increased translational and rotational forces were applied. Because knee braces decreased tibial rotation, they can possibly be used with ACL-reconstructed and ACL-deficient patients to prevent such problems. Case-control study, Level III.

  16. [The geometry of the keel determines the behaviour of the tibial tray against torsional forces in total knee replacement].

    PubMed

    García David, S; Cortijo Martínez, J A; Navarro Bermúdez, I; Maculé, F; Hinarejos, P; Puig-Verdié, L; Monllau, J C; Hernández Hermoso, J A

    2014-01-01

    The keel design of the tibial tray is essential for the transmission of the majority of the forces to the peripheral bone structures, which have better mechanical proprieties, thus reducing the risk of loosening. The aim of the present study was to compare the behaviour of different tibial tray designs submitted to torsional forces. Four different tibial components were modelled. The 3-D reconstruction was made using the Mimics software. The solid elements were generated by SolidWorks. The finite elements study was done by Unigraphics. A torsional force of 6 Nm. applied to the lateral aspects of each tibial tray was simulated. The GENUTECH® tibial tray, with peripheral trabecular bone support, showed a lower displacement and less transmitted tensions under torsional forces. The results suggest that a tibial tray with more peripheral support behaves mechanically better than the other studied designs. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  17. Does lateral versus medial exposure influence total knee tibial component final external rotation? A CT based study.

    PubMed

    Passeron, D; Gaudot, F; Boisrenoult, P; Fallet, L; Beaufils, P

    2009-10-01

    A previous study demonstrated that performing a total knee arthroplasty through a lateral approach including anterior tibial tuberosity (ATT) osteotomy (refixed in its original position) presented numerous advantages: correcting the preoperative patella lateral tilt and improving postoperative patella tracking. We hypothesized that these improvements in patella centering were, at least in part, due to an increased external rotation of the tibial component. Postoperative scannographic studies were, therefore, undertaken to measure tibial component rotation and analyze the results according the medial and lateral exposure used. Rotational positioning of the tibial component is influenced by the lateral or medial approach selected at surgery. Forty-five CAT scans, performed according to the protocol criteria of the French Hip and Knee Society (SFHG), were studied 3 months postoperatively: 15 knees operated through the lateral approach and 30 knees operated through a standard medial approach. The total knee utilized in all these cases was a posteriorly stabilized, fixed-bearing, design. We measured first the angle formed between the perpendicular to the transverse axis of the tibial component and the axis joining the ATT to the center of the knee; second we also measured the coronal distance between the center of the component and the anterior tibial tuberosity (ATT). In the group using the medial approach, the lateral position of the ATT was 7 + or - 3mm with a rotation angle of 18 degrees . In the group using the lateral approach these measurements were respectively 1 + or - 4mm and 2 degrees (p<0.0001). External rotation of the tibial component is substantially increased by the lateral approach compared to the medial approach. Better exposure of the lateral tibial plateau is probably responsible of this difference. This increased external rotation improves postoperative patella tracking. Prospective; comparative; non-randomized study; level 3. 2009 Elsevier Masson

  18. Reconstruction of bilateral tibial aplasia and split hand-foot syndrome in a father and daughter.

    PubMed

    Al Kaissi, Ali; Ganger, Rudolf; Klaushofer, Klaus; Grill, Franz

    2014-01-01

    Tibial aplasia is of heterogeneous aetiology, the majority of reports are sporadic. We describe the reconstruction procedures in two subjects - a daughter and father manifested autosomal dominant (AD) inheritance of the bilateral tibial aplasia and split hand-foot syndrome. Reconstruction of these patients required multiple surgical procedures and orthoprosthesis was mandatory. The main goal of treatment was to achieve walking. Stabilization of the ankle joint by fibular-talar-chondrodesis on both sides, followed by bilateral Brown-procedure at the knee joint level has been applied accordingly. The outcome was with improved function of the deformed limbs and walking was achieved with simultaneous designation of orthotic fitting. This is the first study encompassing the diagnosis and management of a father and daughter with bilateral tibial aplasia associated with variable split hand/foot deformity without foot ablation. Our patients showed the typical AD pattern of inheritance of split-hand/foot and tibial aplasia.

  19. Return to Sport After Tibial Shaft Fractures

    PubMed Central

    Robertson, Greg A. J.; Wood, Alexander M.

    2015-01-01

    Context: Acute tibial shaft fractures represent one of the most severe injuries in sports. Return rates and return-to-sport times after these injuries are limited, particularly with regard to the outcomes of different treatment methods. Objective: To determine the current evidence for the treatment of and return to sport after tibial shaft fractures. Data Sources: OVID/MEDLINE (PubMed), EMBASE, CINAHL, Cochrane Collaboration Database, Web of Science, PEDro, SPORTDiscus, Scopus, and Google Scholar were all searched for articles published from 1988 to 2014. Study Selection: Inclusion criteria comprised studies of level 1 to 4 evidence, written in the English language, that reported on the management and outcome of tibial shaft fractures and included data on either return-to-sport rate or time. Studies that failed to report on sporting outcomes, those of level 5 evidence, and those in non–English language were excluded. Study Design: Systematic review. Level of Evidence: Level 4. Data Extraction: The search used combinations of the terms tibial, tibia, acute, fracture, athletes, sports, nonoperative, conservative, operative, and return to sport. Two authors independently reviewed the selected articles and created separate data sets, which were subsequently combined for final analysis. Results: A total of 16 studies (10 retrospective, 3 prospective, 3 randomized controlled trials) were included (n = 889 patients). Seventy-six percent (672/889) of the patients were men, with a mean age of 27.7 years. Surgical management was assessed in 14 studies, and nonsurgical management was assessed in 8 studies. Return to sport ranged from 12 to 54 weeks after surgical intervention and from 28 to 182 weeks after nonsurgical management (mean difference, 69.5 weeks; 95% CI, –83.36 to −55.64; P < 0.01). Fractures treated surgically had a return-to-sport rate of 92%, whereas those treated nonsurgically had a return rate of 67% (risk ratio, 1.37; 95% CI, 1.20 to 1.57; P < 0

  20. Analysis of Knee Joint Line Obliquity after High Tibial Osteotomy.

    PubMed

    Oh, Kwang-Jun; Ko, Young Bong; Bae, Ji Hoon; Yoon, Suk Tae; Kim, Jae Gyoon

    2016-11-01

    The aim of this study was to evaluate which lower extremity alignment (knee and ankle joint) parameters affect knee joint line obliquity (KJLO) in the coronal plane after open wedge high tibial osteotomy (OWHTO). Overall, 69 knees of patients that underwent OWHTO were evaluated using radiographs obtained preoperatively and from 6 weeks to 3 months postoperatively. We measured multiple parameters of knee and ankle joint alignment (hip-knee-ankle angle [HKA], joint line height [JLH], posterior tibial slope [PS], femoral condyle-tibial plateau angle [FCTP], medial proximal tibial angle [MPTA], mechanical lateral distal femoral angle [mLDFA], KJLO, talar tilt angle [TTA], ankle joint obliquity [AJO], and the lateral distal tibial ground surface angle [LDTGA]; preoperative [-pre], postoperative [-post], and the difference between -pre and -post values [-Δ]). We categorized patients into two groups according to the KJLO-post value (the normal group [within ± 4 degrees, 56 knees] and the abnormal group [greater than ± 4 degrees, 13 knees]), and compared their -pre parameters. Multiple logistic regression analysis was used to examine the contribution of the -pre parameters to abnormal KJLO-post. The mean HKA-Δ (-9.4 ± 4.7 degrees) was larger than the mean KJLO-Δ (-2.1 ± 3.2 degrees). The knee joint alignment parameters (the HKA-pre, FCTP-pre) differed significantly between the two groups ( p  < 0.05). In addition, the HKA-pre (odds ratio [OR] = 1.27, p  = 0.006) and FCTP-pre (OR = 2.13, p  = 0.006) were significant predictors of abnormal KJLO-post. However, -pre ankle joint parameters (TTA, AJO, and LDTGA) did not differ significantly between the two groups and were not significantly associated with the abnormal KJLO-post. The -pre knee joint alignment and knee joint convergence angle evaluated by HKA-pre and FCTP-pre angle, respectively, were significant predictors of abnormal KJLO after OWHTO. However, -pre ankle joint

  1. Study of the anatomy of the tibial nerve and its branches in the distal medial leg.

    PubMed

    Torres, André Leal Gonçalves; Ferreira, Marcus Castro

    2012-01-01

    Determine, through dissection in fresh cadavers, the topographic anatomy of the tibial nerve and its branches at the ankle, in relation to the tarsal tunnel. Bilateral dissections were performed on 26 fresh cadavers and the locations of the tibial nerve bifurcation and its branches were measured in millimeters. For the calcaneal branches, the amount and their respective nerves of origin were also analyzed. The tibial nerve bifurcation occurred under the tunnel in 88% of the cases and proximally in 12%. As for the calcaneal branches, the medial presented with one (58%), two (34%) and three (8%) branches, with the most common source occurring in the tibial nerve (90%) and the lower with a single branch per leg and lateral plantar nerve as the most common origin (70%). Level of Evidence, V Expert opinion .

  2. The effects of sectioning the spring ligament on rearfoot stability and posterior tibial tendon efficiency.

    PubMed

    Jennings, Meagan M; Christensen, Jeffery C

    2008-01-01

    Posterior tibial tendon insufficiency has been implicated as a cause of adult acquired flatfoot. Multiple theories are debated as to whether or not a flatfoot deformity develops secondary to insufficiency of the posterior tibial tendon or of the ligamentous structures such as the spring ligament complex. This cadaveric study was undertaken in an attempt to determine the effect that sectioning the spring ligament complex has on foot stability, and whether engagement of the posterior tibial tendon would be able to compensate for the loss of the spring ligament complex. A 3-dimensional kinematic system and a custom-loading frame were used to quantify rotation about the talus, navicular, and calcaneus in 5 cadaveric specimens, before and after sectioning the spring ligament complex, while incremental tension was applied to the posterior tibial tendon. This study demonstrated that sectioning the spring ligament complex created instability in the foot for which the posterior tibial tendon was unable to compensate. Sectioning the spring ligament complex also produced significant changes in talar, navicular, and calcaneal rotations. During simulated midstance, the navicular plantarflexed, adducted, and everted; the talar head plantarflexed, adducted, and inverted; and the calcaneus plantarflexed, abducted, and everted, after sectioning the spring ligament complex. The results of this study indicate that the spring ligament complex is the major stabilizer of the arch during midstance and that the posterior tibial tendon is incapable of fully accommodating for its insufficiency, suggesting that the spring ligament complex should be evaluated and, if indicated, repaired in flatfoot reconstruction. 5.

  3. Survivorship comparison of all-polyethylene and metal-backed tibial components in cruciate-substituting total knee arthroplasty--Chinese experience.

    PubMed

    Shen, Bin; Yang, Jing; Zhou, Zongke; Kang, Pengde; Wang, Liao; Pei, Fuxing

    2009-10-01

    Considering its cost saving, the all-polyethylene tibial component is of potential interest in developing countries like China. But to our knowledge, a survivorship comparison of all-polyethylene and metal-backed tibial components in posterior cruciate ligament-substituting total knee arthroplasty (PS-TKA) has not been studied in China previously. Using survivorship analysis, we have studied the midterm outcome of 34 cemented PS-TKA using an all-polyethylene tibial component and of 34 cemented PS-TKA using a metal-backed tibial component which has an identical articular surface with all-polyethylene tibial components. All operations were performed by the same group of surgeons; 58 patients underwent a unilateral operation and five patients a bilateral operation. These patients had a mean follow-up of 5.9 years (range: 5-7 years); three patients were lost to follow-up and one was revised for infection. No significant difference between the two groups was reported regarding HSS scores, ROM, clinical and radiographic parameters measured and survival rates. Although the Asian lifestyle includes more squatting and bending of the knee, the results of this series of TKA using all-polyethylene tibial components in Chinese people are comparable to the satisfactory results of other reported all-polyethylene series whose patients are mainly Western people. Considering its cost saving and excellent clinical result, the all-polyethylene tibial component is of potential interest in developing countries.

  4. Effect of tibial plateau leveling osteotomy on femorotibial contact mechanics and stifle kinematics.

    PubMed

    Kim, Stanley E; Pozzi, Antonio; Banks, Scott A; Conrad, Bryan P; Lewis, Daniel D

    2009-01-01

    To evaluate the effects of tibial plateau leveling osteotomy (TPLO) on femorotibial contact mechanics and 3-dimensional (3D) kinematics in cranial cruciate ligament (CrCL)-deficient stifles of dogs. In vitro biomechanical study. Unpaired pelvic limbs from 8 dogs, weighing 28-35 kg. Digital pressure sensors placed subjacent to the menisci were used to measure femorotibial contact force, contact area, peak and mean contact pressure, and peak pressure location with the limb under an axial load of 30% body weight and a stifle angle of 135 degrees. Three-dimensional static poses of the stifle were obtained using a Microscribe digitizing arm. Each specimen was tested under normal, CrCL-deficient, and TPLO-treated conditions. Repeated measures analysis of variance with a Tukey post hoc test (P<.05) was used for statistical comparison. Significant disturbances to all measured contact mechanical variables were evident after CrCL transection, which corresponded to marked cranial tibial subluxation and increased internal tibial rotation in the CrCL-deficient stifle. No significant differences in 3D femorotibial alignment were observed between normal and TPLO-treated stifles; however, femorotibial contact area remained significantly smaller and peak contact pressures in both medial and lateral stifle compartments were positioned more caudally on the tibial plateau, when compared with normal. Whereas TPLO eliminates craniocaudal stifle instability during simulated weight bearing, the procedure fails to concurrently restore femorotibial contact mechanics to normal. Progression of stifle osteoarthritis in dogs treated with TPLO may be partly the result of abnormal stifle contact mechanics induced by altering the orientation of the proximal tibial articulating surface.

  5. Fat-suppressed three-dimensional spoiled gradient-echo MR imaging of hyaline cartilage defects in the knee: comparison with standard MR imaging and arthroscopy.

    PubMed

    Disler, D G; McCauley, T R; Kelman, C G; Fuchs, M D; Ratner, L M; Wirth, C R; Hospodar, P P

    1996-07-01

    The sensitivity of fat-suppressed three-dimensional spoiled gradient-echo (SPGR) images was compared with that of standard MR images for detecting hyaline cartilage defects of the knee, using arthroscopy as the standard of reference. We assessed 114 consecutive patients for hyaline cartilage defects of the knee with both standard MR imaging sequences and a sagittal fat-suppressed three-dimensional SPGR sequence. Of these patients, 48 with meniscal or ligament injury, or persistent symptoms, underwent subsequent arthroscopy. The standard MR images and SPGR images of these 48 patients were then retrospectively analyzed for articular defects in a blinded fashion by two independent observers. Sensitivity, specificity, and intraobserver and interobserver agreement were determined for the different imaging techniques. One fourth of the patients who went on to arthroscopy were shown to have isolated hyaline cartilage lesions that were clinically confused with meniscal tears and that were missed on the standard MR images. When looking at all surfaces combined for each reader, the SPGR imaging sequence had a significantly higher sensitivity than the standard MR imaging sequences for detecting hyaline cartilage defects (75-85% versus 29-38%, p < .001 for each comparison). When looking at individual surfaces for each reader, significant differences in sensitivity were shown for each surface except the trochlear and lateral tibial surfaces. We found no difference in specificity (97% versus 97%, p > .99). We also found that combined evaluation of standard MR and SPGR images gave no added diagnostic advantage (sensitivity, 86%; specificity, 97%; p > .42). Except for the lateral tibial surface, the study achieved excellent reproducibility among readings and between readers. Fat-suppressed three-dimensional SPGR imaging is more sensitive than standard MR imaging for the detection of hyaline cartilage defects of the knee.

  6. Studying post-etching silicon crystal defects on 300mm wafer by automatic defect review AFM

    NASA Astrophysics Data System (ADS)

    Zandiatashbar, Ardavan; Taylor, Patrick A.; Kim, Byong; Yoo, Young-kook; Lee, Keibock; Jo, Ahjin; Lee, Ju Suk; Cho, Sang-Joon; Park, Sang-il

    2016-03-01

    Single crystal silicon wafers are the fundamental elements of semiconductor manufacturing industry. The wafers produced by Czochralski (CZ) process are very high quality single crystalline materials with known defects that are formed during the crystal growth or modified by further processing. While defects can be unfavorable for yield for some manufactured electrical devices, a group of defects like oxide precipitates can have both positive and negative impacts on the final device. The spatial distribution of these defects may be found by scattering techniques. However, due to limitations of scattering (i.e. light wavelength), many crystal defects are either poorly classified or not detected. Therefore a high throughput and accurate characterization of their shape and dimension is essential for reviewing the defects and proper classification. While scanning electron microscopy (SEM) can provide high resolution twodimensional images, atomic force microscopy (AFM) is essential for obtaining three-dimensional information of the defects of interest (DOI) as it is known to provide the highest vertical resolution among all techniques [1]. However AFM's low throughput, limited tip life, and laborious efforts for locating the DOI have been the limitations of this technique for defect review for 300 mm wafers. To address these limitations of AFM, automatic defect review AFM has been introduced recently [2], and is utilized in this work for studying DOI on 300 mm silicon wafer. In this work, we carefully etched a 300 mm silicon wafer with a gaseous acid in a reducing atmosphere at a temperature and for a sufficient duration to decorate and grow the crystal defects to a size capable of being detected as light scattering defects [3]. The etched defects form a shallow structure and their distribution and relative size are inspected by laser light scattering (LLS). However, several groups of defects couldn't be properly sized by the LLS due to the very shallow depth and low

  7. The Critical Size Defect as an Experimental Model for Craniomaxillofacial Nonunions,

    DTIC Science & Technology

    1985-01-01

    union evident at two months. The wider defects of 12 m, 15 m, and 18 mm in length exhibited bony union in four months but exhibited drainage either...Prolo, D.J., (-btierrez, R.V., DeVine, J.S., and (*und, R.A.: Clinical l1tility of Alloqeneic Skull Discs in Human Craniotomy . Neurosurgery. 14:1R3, 1984...1. R rm craniotomy defect prepared in dried rat skull. Piq. 2. 15 rm craniotamy defect in dried rabbit skull. Fig. 3. r-ied dog mandible qhowing

  8. Tibial plateau fracture after primary anatomic double-bundle anterior cruciate ligament reconstruction: a case report.

    PubMed

    Gobbi, Alberto; Mahajan, Vivek; Karnatzikos, Georgios

    2011-05-01

    Tibial plateau fracture after primary anatomic double-bundle anterior cruciate ligament (ACL) reconstruction is rare. To our knowledge, this is the first case report of a tibial plateau fracture after primary anatomic double-bundle ACL reconstruction. In our patient the tibial plateau fracture occurred after a torsional injury to the involved extremity. The fracture occurred 4.5 years after the ACL reconstruction. The fracture was intra-articular Schatzker type IV and had a significant displacement. The patient was treated operatively by open reduction-internal fixation. He recovered well. Copyright © 2011 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  9. Negative pressure wound therapy for Gustilo Anderson grade IIIb open tibial fractures.

    PubMed

    Park, Chul Hyun; Shon, Oog Jin; Kim, Gi Beom

    2016-09-01

    Traditionally, Gustilo Anderson grade IIIb open tibial fractures have been treated by initial wide wound debridement, stabilization of fracture with external fixation, and delayed wound closure. The purpose of this study is to evaluate the clinical and radiological results of staged treatment using negative pressure wound therapy (NPWT) for Gustilo Anderson grade IIIb open tibial fractures. 15 patients with Gustilo Anderson grade IIIb open tibial fractures, treated using staged protocol by a single surgeon between January 2007 and December 2011 were reviewed in this retrospective study. The clinical results were assessed using a Puno scoring system for severe open fractures of the tibia at the last followup. The range of motion (ROM) of the knee and ankle joints and postoperative complication were evaluated at the last followup. The radiographic results were assessed using time to bone union, coronal and sagittal angulations and a shortening at the last followup. The mean score of Puno scoring system was 87.4 (range 67-94). The mean ROM of the knee and ankle joints was 121.3° (range 90°-130°) and 37.7° (range 15°-50°), respectively. Bone union developed in all patients and the mean time to union was 25.3 weeks (range 16-42 weeks). The mean coronal angulation was 2.1° (range 0-4°) and sagittal was 2.7° (range 1-4°). The mean shortening was 4.1 mm (range 0-8 mm). Three patients had partial flap necrosis and 1 patient had total flap necrosis. There was no superficial and deep wound infection. Staged treatment using NPWT decreased the risks of infection and requirement of flap surgeries in Gustilo Anderson grade IIIb open tibial fractures. Therefore, staged treatment using NPWT could be a useful treatment option for Gustilo Anderson grade IIIb open tibial fractures.

  10. Relationship between product demand, tibial polyethylene insert shelf age, and total knee arthroplasty survival: retrospective review of total knees of one design.

    PubMed

    Urban, Joshua A; Collier, Matthew B; Engh, C Anderson; Engh, Gerard A

    2006-04-01

    Shelf aging of gamma-irradiated-in-air polyethylene tibial components has been associated with increased articular surface wear and an elevated risk for revision. Nine hundred fifty cruciate-retaining inserts of one design were implanted between 1987 and 1996 (shelf age, 1.0 +/- 1.2 years). Less frequently used inserts (smallest/largest sizes, thicker thicknesses, supplemental articular constraint) had longer shelf ages (means ranged from 1.2 to 2.6 years). Survival analysis showed that shelf age (P < .01) and gamma-sterilization in air (P = .01) elevated the risk for revision. Surgeons must remain attentive to identify the shelf-aged gamma-irradiated-in-air polyethylene tibial component while following designs from the era when this sterilization method was used. Recognition is expedited by understanding how shelf life is related to product demand and can be of aid when diagnosing the painful knee.

  11. Quantitative Comparison of the Microscopic Anatomy of the Human ACL Femoral and Tibial Entheses

    PubMed Central

    Beaulieu, Mélanie L.; Carey, Grace E.; Schlecht, Stephen H.; Wojtys, Edward M.; Ashton-Miller, James A.

    2015-01-01

    The femoral enthesis of the human anterior cruciate ligament (ACL) is known to be more susceptible to injury than the tibial enthesis. To determine whether anatomic differences might help explain this difference, we quantified the microscopic appearance of both entheses in 15 unembalmed knee specimens using light microscopy, toluidine blue stain and image analysis. The amount of calcified fibrocartilage and uncalcified fibrocartilage, and the ligament entheseal attachment angle were then compared between the femoral and tibial entheses via linear mixed-effects models. The results showed marked differences in anatomy between the two entheses. The femoral enthesis exhibited a 3.9-fold more acute ligament attachment angle than the tibial enthesis (p < 0.001), a 43% greater calcified fibrocartilage tissue area (p < 0.001), and a 226% greater uncalcified fibrocartilage depth (p < 0.001), with the latter differences being particularly pronounced in the central region. We conclude that the ACL femoral enthesis has more fibrocartilage and a more acute ligament attachment angle than the tibial enthesis, which provides insight into why it is more vulnerable to failure. PMID:26134706

  12. Intracardiac Ultrasound Assessment of Atrial Septal Defect: Comparison with Transthoracic Echocardiographic, Angiocardiographic, and Balloon-Sizing Measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sheng-Ling, Jan; Hwang, Betau; Lee, P.-C.

    Purpose: Accurate evaluation of the size, location and adjacent structure of an atrial septal defect (ASD) is very important in the selection of patients for further management. We directly compared the utility of transthoracic echocardiography, angiocardiography, balloon sizing, and intracardiac ultrasound (ICUS) in the detection of ASD.Methods: Twenty-one children underwent an ICUS study of ASD after routine clinical and laboratory studies. All patients had received transthoracic echocardiography (TTE), cardiac catheterization, cineangiography, and balloon sizing before the ICUS to evaluate the ASD.Results: There was a significant correlation between the ICUS-derived ASD diameter and the other methods (p < 0.001). The balloon-sizingmore » diameter was estimated by the equation: TTE diameter x 1.09 + 3.9 mm. There was a good correlation between the predicted and measured balloon-sizing diameter (r = 0.963; p < 0.001).Conclusion: It is worthwhile spending a few minutes to perform ICUS during cardiac catheterization since it will provide more detailed information on and high resolution images of atrial septal morphology, especially for patients undergoing transcatheter closure by device.« less

  13. Nano-size defects in arsenic-implanted HgCdTe films: a HRTEM study

    NASA Astrophysics Data System (ADS)

    Bonchyk, O. Yu.; Savytskyy, H. V.; Swiatek, Z.; Morgiel, Y.; Izhnin, I. I.; Voitsekhovskii, A. V.; Korotaev, A. G.; Mynbaev, K. D.; Fitsych, O. I.; Varavin, V. S.; Dvoretsky, S. A.; Marin, D. V.; Yakushev, M. V.

    2018-02-01

    Radiation damage and its transformation under annealing were studied with bright-field and high-resolution transmission electron microscopy for arsenic-implanted HgCdTe films with graded-gap surface layers. In addition to typical highly defective layers in as-implanted material, a 50 nm-thick sub-surface layer with very low defect density was observed. The main defects in other layers after implantation were dislocation loops, yet after arsenic activation annealing, the dominating defects were single dislocations. Transport (from depth to surface), transformation and annihilation of radiation-induced defects were observed as a result of annealing, with the depth with the maximum defect density decreasing from 110 to 40 nm.

  14. A Case of Nonunion Avulsion Fracture of the Anterior Tibial Eminence

    PubMed Central

    Atsumi, Satoru; Arai, Yuji; Nakagawa, Shuji; Inoue, Hiroaki; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Kubo, Toshikazu

    2016-01-01

    Avulsion fracture of the anterior tibial eminence is an uncommon injury. If bone union does not occur, knee extension will be limited by impingement of the avulsed fragment and knee instability will be induced by dysfunction of the anterior cruciate ligament (ACL). This report describes a 55-year-old woman who experienced an avulsion fracture of the right anterior tibial eminence during recreational skiing. Sixteen months later, she presented at our hospital with limitation of right knee extension. Plain radiography showed nonunion of the avulsion fracture region, and arthroscopy showed that the avulsed fragment impinged the femoral intercondylar notch during knee extension. The anterior region of the bony fragment was debrided arthroscopically until the knee could be extended completely. There was no subsequent instability, and the patient was able to climb a mountain 6 months after surgery. These findings indicate that arthroscopic debridement of an avulsed fragment for nonunion of an avulsion fracture of the anterior tibial eminence is a minimally invasive and effective treatment for middle-aged and elderly patients with a low level of sports activity. PMID:27119035

  15. Study of the anatomy of the tibial nerve and its branches in the distal medial leg

    PubMed Central

    Torres, André Leal Gonçalves; Ferreira, Marcus Castro

    2012-01-01

    Objective Determine, through dissection in fresh cadavers, the topographic anatomy of the tibial nerve and its branches at the ankle, in relation to the tarsal tunnel. Methods Bilateral dissections were performed on 26 fresh cadavers and the locations of the tibial nerve bifurcation and its branches were measured in millimeters. For the calcaneal branches, the amount and their respective nerves of origin were also analyzed. Results The tibial nerve bifurcation occurred under the tunnel in 88% of the cases and proximally in 12%. As for the calcaneal branches, the medial presented with one (58%), two (34%) and three (8%) branches, with the most common source occurring in the tibial nerve (90%) and the lower with a single branch per leg and lateral plantar nerve as the most common origin (70%). Level of Evidence, V Expert opinion. PMID:24453596

  16. Quadriceps force and anterior tibial force occur obviously later than vertical ground reaction force: a simulation study.

    PubMed

    Ueno, Ryo; Ishida, Tomoya; Yamanaka, Masanori; Taniguchi, Shohei; Ikuta, Ryohei; Samukawa, Mina; Saito, Hiroshi; Tohyama, Harukazu

    2017-11-18

    Although it is well known that quadriceps force generates anterior tibial force, it has been unclear whether quadriceps force causes great anterior tibial force during the early phase of a landing task. The purpose of the present study was to examine whether the quadriceps force induced great anterior tibial force during the early phase of a landing task. Fourteen young, healthy, female subjects performed a single-leg landing task. Muscle force and anterior tibial force were estimated from motion capture data and synchronized force data from the force plate. One-way repeated measures analysis of variance and the post hoc Bonferroni test were conducted to compare the peak time of the vertical ground reaction force, quadriceps force and anterior tibial force during the single-leg landing. In addition, we examined the contribution of vertical and posterior ground reaction force, knee flexion angle and moment to peak quadriceps force using multiple linear regression. The peak times of the estimated quadriceps force (96.0 ± 23.0 ms) and anterior tibial force (111.9 ± 18.9 ms) were significantly later than that of the vertical ground reaction force (63.5 ± 6.8 ms) during the single-leg landing. The peak quadriceps force was positively correlated with the peak anterior tibial force (R = 0.953, P < 0.001). Multiple linear regression analysis showed that the peak knee flexion moment contributed significantly to the peak quadriceps force (R 2  = 0.778, P < 0.001). The peak times of the quadriceps force and the anterior tibial force were obviously later than that of the vertical ground reaction force for the female athletes during successful single-leg landings. Studies have reported that the peak time of the vertical ground reaction force was close to the time of anterior cruciate ligament (ACL) disruption in ACL injury cases. It is possible that early contraction of the quadriceps during landing might induce ACL disruption as a result of

  17. Biomaterial-Stabilized Soft Tissue Healing for Healing of Critical-Sized Bone Defects: the Masquelet Technique.

    PubMed

    Tarchala, Magdalena; Harvey, Edward J; Barralet, Jake

    2016-03-01

    Critical-sized bone defects present a significant burden to the medical community due to their challenging treatment. However, a successful limb-salvaging technique, the Masquelet Technique (MT), has significantly improved the prognosis of many segmental bone defects in helping to restore form and function. Although the Masquelet Technique has proven to be clinically effective, the physiology of the healing it induces is not well understood. Multiple modifiable factors have been implicated by various surgical and research teams, but no single factor has been proven to be critical to the success of the Masquelet Technique. In this review the most recent clinical and experimental evidence that supports and helps to decipher the traditional Masquelet, as well as the modifiable factors and their effect on the success of the technique are discussed. In addition, future developments for the integration of the traditional Masquelet Technique with the use of alternative biomaterials to increase the effectiveness and expand the clinical applicability of the Masquelet Technique are reviewed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Eddy current inspection of weld defects in tubing

    NASA Technical Reports Server (NTRS)

    Katragadda, G.; Lord, W.

    1992-01-01

    An approach using differential probes for the inspection of weld defects in tubing is studied. Finite element analysis is used to model the weld regions and defects. Impedance plane signals are predicted for different weld defect types and compared wherever possible with signals from actual welds in tubing. Results show that detection and sizing of defects in tubing is possible using differential eddy current techniques. The phase angle of the impedance plane trajectory gives a good indication of the sizing of the crack. Data on the type of defect can be obtained from the shape of the impedance plane trajectory and the phase. Depending on the skin depth, detection of outer wall, inner wall, and subsurface defects is possible.

  19. In Vivo Tibial Fit and Rotational Analysis of a Customized, Patient-Specific TKA versus Off-the-Shelf TKA.

    PubMed

    Schroeder, Lennart; Martin, Gregory

    2018-05-25

    In total knee arthroplasty (TKA), surgeons often face the decision of maximizing tibial component fit and achieving correct rotational alignment at the same time. Customized implants (CIMs) address this difficulty by aiming to replicate the anatomical joint structure, utilizing data from patient-specific knee geometry during the manufacturing. We intraoperatively compared component fit in four tibial zones of a CIM to that of three different off-the-shelf (OTS) TKA designs in 44 knees. Additionally, we assessed the rotational alignment of the tibia using computed tomography (CT)-based computer aided design model analysis. Overall the CIM device showed significantly better component fit than the OTS TKAs. While 18% of OTS designs presented an implant overhang of 3 mm or more, none of the CIM components did ( p  < 0.05). There was a larger percentage of CIMs seen with optimal fit (≤1 mm implant overhang to ≤1 mm tibial bone undercoverage) than in OTS TKAs. Also, OTS implants showed significantly more component underhang of ≥3 mm than the CIM design (37 vs. 18%). The rotational analysis revealed that 45% of the OTS tibial components showed a rotational deviation of more than 5 degrees and 4% of more than 10 degrees to a tibial rotational axis described by Cobb et al. No deviation was seen for the CIM, as the device is designed along this axis. Using the medial one-third of the tibial tubercle as the rotational landmark, 95% of the OTS trays demonstrated a rotational deviation of more than 5 degrees and 73% of more than 10 degrees compared with 73% of CIM tibial trays with more than 5 degrees and 27% with more than 10 degrees. Based on our findings, we believe that the CIM TKA provides both better rotational alignment and tibial fit without causing overhang of the tibial tray than the three examined OTS implants. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  20. Adhesion characterization and defect sizing of sandwich honeycomb composites.

    PubMed

    Ndiaye, Elhadji Barra; Maréchal, Pierre; Duflo, Hugues

    2015-09-01

    Defects may appear in composite structures during their life cycle. A 10MHz 128 elements phased array transducer was investigated to characterize join bonds and defects in sandwich honeycomb composite structures. An adequate focal law throughout the composite skin gives the ultrasonic dispersive properties of the composite skin and glue layer behind. The resulting B-scan cartographies allow characterizing locally the honeycomb adhesion. Experimental measurements are compared in good agreement with the Debye Series Method (DSM). In the processed C-scan image, flaws are detectable and measurable, localized both in the scanning plane and in the thickness of the composite skin. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. How to deal with atrial septal defect closure from right internal jugular vein: Role of venous-arterial circuit for sizing and over-the-wire device implantation.

    PubMed

    Butera, Gianfranco; Lovin, Nicusor; Basile, Domenica Paola

    2017-01-01

    Secundum atrial septum defect (ASD) is the most common congenital heart disease. It is usually treated by a transcatheter approach using a femoral venous access. In case of bilateral femoral vein occlusion, the internal jugular venous approach for ASD closure is an option, in particular in cases where ASD balloon occlusion test and sizing is needed. Here, we report on a new technique for ASD closure using a venous-arterial circuit from the right internal jugular vein to the femoral artery. Two patients (females, 4 and 10 years of age) had occlusion of both femoral veins because of a previous history of pulmonary atresia and intact ventricular septum, for which they underwent percutaneous radiofrequency perforation and balloon angioplasty. These subjects needed balloon occlusion test of a residual ASD to size the hole and to check for hemodynamic suitability to ASD closure. After performing a venous-arterial circuit, a 24 mm St Jude ASD sizing balloon catheter was advanced over the circuit and the defect closed for 15 min to check hemodynamics and size the defect. ASD was closed is hemodinamically suitable. This technique was safe and reliable. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Perforator Propeller Flaps for the Coverage of Middle and Distal Leg Soft-tissue Defects

    PubMed Central

    Cabrera, Rodrigo; Siu, Armando; Altamirano, Roderick; Gutierrez, Sandra

    2018-01-01

    Background: Local propeller flaps preserve the main vascular arteries of the lower extremity and muscle function, avoiding the need for a microsurgical anastomosis and the benefit of providing a “like with like” coverage. Our goal in this study was to demonstrate the versatility, safety, and complications of the local propeller flaps for lower extremity reconstruction. Methods: We present a series of 28 patients in whom we used local propeller flaps to restore small-to-medium soft-tissue defects of the lower limb in different hospitals of Managua, Nicaragua. Results: Flap average dimensions were of 48 cm2. Flap rotation was performed in 180 degrees in 85% of the cases. The propeller flaps were based on a single perforator, from the posterior tibial artery in 50%, anterior tibial artery in 39.3%, and peroneal artery in 10.7% of the cases. Complications occurred in 14% of the propeller flaps performed, with 3 partial necrosis of less than 15% of the flap transposed. Complications of the patients occurred in both sex groups; however, for the female group, there was a 75% of complications with a tendency toward statistical significance of P = 0.038. Donor site of the flap was closed primarily in 85.7% (24) of the cases. Conclusions: In our opinion, the availability and safety of local propeller flaps, justifies its use in cases where microsurgical techniques are not an option for the reconstruction of the middle and distal extremity, in small-to-medium defects of soft-tissue coverage of the lower limb. PMID:29922552

  3. Foot and ankle function after tibial overlengthening.

    PubMed

    Emara, Khaled M; Diab, Ramy Ahmed; El Ghazali, Sherif; Farouk, Amr; El Kersh, Mohamed Ahmed

    2014-01-01

    Lengthening the tibia more than 25% of its original length can be indicated for proximal femoral deficiency, poliomyelitis, or femoral infected nonunion. Such lengthening of the tibia can adversely affect the ankle or foot shape and function. The present study aimed to assess the effect of tibial lengthening of more than 25% of its original length on the foot and ankle shape and function compared with the preoperative condition. This was a retrospective study of 13 children with severe proximal focal femoral deficiency, Aitken classification type D, who had undergone limb lengthening from June 2000 to June 2008 using Ilizarov external fixators. The techniques used in tibial lengthening included lengthening without intramedullary rodding and lengthening over a nail. The foot assessment was done preoperatively, at fixator removal, and then annually for 3 years, documenting the range of motion and deformity of the ankle and subtalar joints and big toe and the navicular height, calcaneal pitch angle, and talo-first metatarsal angle. At fixator removal, all cases showed equinocavovarus deformity, with decreased ankle, subtalar, and big toe motion. The mean American Orthopedic Foot and Ankle Society score was significantly reduced. During follow-up, the range of motion, foot deformity, and American Orthopedic Foot and Ankle Society score improved, reaching nearly to the preoperative condition by 2 years of follow-up. The results of our study have shown that tibial overlengthening has an adverse effect on foot and ankle function. This effect was reversible in the patients included in the present study. Lengthening of more than 25% can be safely done after careful discussion with the patients and their families about the probable effects of lengthening on foot and ankle function. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  4. Medial tibial stress syndrome: a critical review.

    PubMed

    Moen, Maarten H; Tol, Johannes L; Weir, Adam; Steunebrink, Miriam; De Winter, Theodorus C

    2009-01-01

    Medial tibial stress syndrome (MTSS) is one of the most common leg injuries in athletes and soldiers. The incidence of MTSS is reported as being between 4% and 35% in military personnel and athletes. The name given to this condition refers to pain on the posteromedial tibial border during exercise, with pain on palpation of the tibia over a length of at least 5 cm. Histological studies fail to provide evidence that MTSS is caused by periostitis as a result of traction. It is caused by bony resorption that outpaces bone formation of the tibial cortex. Evidence for this overloaded adaptation of the cortex is found in several studies describing MTSS findings on bone scan, magnetic resonance imaging (MRI), high-resolution computed tomography (CT) scan and dual energy x-ray absorptiometry. The diagnosis is made based on physical examination, although only one study has been conducted on this subject. Additional imaging such as bone, CT and MRI scans has been well studied but is of limited value. The prevalence of abnormal findings in asymptomatic subjects means that results should be interpreted with caution. Excessive pronation of the foot while standing and female sex were found to be intrinsic risk factors in multiple prospective studies. Other intrinsic risk factors found in single prospective studies are higher body mass index, greater internal and external ranges of hip motion, and calf girth. Previous history of MTSS was shown to be an extrinsic risk factor. The treatment of MTSS has been examined in three randomized controlled studies. In these studies rest is equal to any intervention. The use of neoprene or semi-rigid orthotics may help prevent MTSS, as evidenced by two large prospective studies.

  5. Survivorship comparison of all-polyethylene and metal-backed tibial components in cruciate-substituting total knee arthroplasty—Chinese experience

    PubMed Central

    Shen, Bin; Yang, Jing; Zhou, Zongke; Kang, Pengde; Wang, Liao

    2008-01-01

    Considering its cost saving, the all-polyethylene tibial component is of potential interest in developing countries like China. But to our knowledge, a survivorship comparison of all-polyethylene and metal-backed tibial components in posterior cruciate ligament-substituting total knee arthroplasty (PS-TKA) has not been studied in China previously. Using survivorship analysis, we have studied the midterm outcome of 34 cemented PS-TKA using an all-polyethylene tibial component and of 34 cemented PS-TKA using a metal-backed tibial component which has an identical articular surface with all-polyethylene tibial components. All operations were performed by the same group of surgeons; 58 patients underwent a unilateral operation and five patients a bilateral operation. These patients had a mean follow-up of 5.9 years (range: 5–7 years); three patients were lost to follow-up and one was revised for infection. No significant difference between the two groups was reported regarding HSS scores, ROM, clinical and radiographic parameters measured and survival rates. Although the Asian lifestyle includes more squatting and bending of the knee, the results of this series of TKA using all-polyethylene tibial components in Chinese people are comparable to the satisfactory results of other reported all-polyethylene series whose patients are mainly Western people. Considering its cost saving and excellent clinical result, the all-polyethylene tibial component is of potential interest in developing countries. PMID:18688613

  6. The effect of retained intramedullary nails on tibial bone mineral density.

    PubMed

    Allen, J C; Lindsey, R W; Hipp, J A; Gugala, Z; Rianon, N; LeBlanc, A

    2008-07-01

    Intramedullary nailing has become a standard treatment for adult tibial shaft fractures. Retained intramedullary nails have been associated with stress shielding, although their long-term effect on decreasing tibial bone mineral density is currently unclear. The purpose of this study was to determine if retained tibial intramedullary nails decrease tibial mineral density in patients with successfully treated fractures. Patients treated with statically locked intramedullary nails for isolated, unilateral tibia shaft fractures were studied. Inclusion required that fracture had healed radiographically and that the patient returned to the pre-injury activity level. Data on patient demographic, fracture type, surgical technique, implant, and post-operative functional status were tabulated. Dual energy X-ray absorptiometry was used to measure bone mineral density in selected regions of the affected tibia and the contralateral intact tibia. Image reconstruction software was employed to ensure symmetry of the studied regions. Twenty patients (mean age 43; range 22-77 years) were studied at a mean of 29 months (range 5-60 months) following intramedullary nailing. There was statistically significant reduction of mean bone mineral density in tibiae with retained intramedullary nails (1.02 g/cm(2) versus 1.06 g/cm(2); P=0.04). A significantly greater decrease in bone mineral density was detected in the reamed versus non-reamed tibiae (-7% versus +6%, respectively; P<0.05). The present study demonstrates a small, but statistically significant overall bone mineral density decrease in healed tibiae with retained nails. Intramedullary reaming appears to be a factor potentiating the reduction of tibia bone mineral density in long-term nail retention.

  7. Metrology to quantify wear and creep of polyethylene tibial knee inserts.

    PubMed

    Muratoglu, Orhun K; Perinchief, Rebecca S; Bragdon, Charles R; O'Connor, Daniel O; Konrad, Reto; Harris, William H

    2003-05-01

    Assessment of damage on articular surfaces of ultrahigh molecular weight polyethylene tibial knee inserts primarily has been limited to qualitative methods, such as visual observation and classification of features such as pitting, delamination, and subsurface cracking. Semiquantitative methods also have been proposed to determine the linear penetration and volume of the scar that forms on articular surfaces of tibial knee inserts. The current authors report a new metrologic method that uses a coordinate measuring machine to quantify the dimensions of this scar. The articular surface of the insert is digitized with the coordinate measuring machine before and after regular intervals of testing on a knee simulator. The volume and linear penetration of the scar are calculated by mathematically taking the difference between the digitized surface maps of the worn and unworn articular surfaces. Three conventional polyethylene tibial knee inserts of a posterior cruciate-sparing design were subjected to five million cycles of normal gait on a displacement-driven knee wear simulator in bovine serum. A metrologic method was used to calculate creep and wear contributions to the scar formation on each tibial plateau. Weight loss of the inserts was determined gravimetrically with the appropriate correction for fluid absorption. The total average wear volume was 43 +/- 9 and 41 +/- 4 mm3 measured by the metrologic and gravimetric methods, respectively. The wear rate averaged 8.3 +/- 0.9 and 8.5 +/- 1.6 mm3 per million cycles measured by the metrologic and gravimetric methods, respectively. These comparisons reflected strong agreement between the metrologic and gravimetric methods.

  8. Surgical treatment of refractory tibial stress fractures in elite dancers: a case series.

    PubMed

    Miyamoto, Ryan G; Dhotar, Herman S; Rose, Donald J; Egol, Kenneth

    2009-06-01

    Treatment of tibial stress fractures in elite dancers is centered on rest and activity modification. Surgical intervention in refractory cases has important implications affecting the dancers' careers. Refractory tibial stress fractures in dancers can be treated successfully with drilling and bone grafting or intramedullary nailing. Case series; Level of evidence, 4. Between 1992 and 2006, 1757 dancers were evaluated at a dance medicine clinic; 24 dancers (1.4%) had 31 tibial stress fractures. Of that subset, 7 (29.2%) elite dancers with 8 tibial stress fractures were treated operatively with either intramedullary nailing or drilling and bone grafting. Six of the patients were followed up closely until they were able to return to dance. One patient was available only for follow-up phone interview. Data concerning their preoperative treatment regimens, operative procedures, clinical union, radiographic union, and time until return to dance were recorded and analyzed. The mean age of the surgical patients at the time of stress fracture was 22.6 years. The mean duration of preoperative symptoms before surgical intervention was 25.8 months. Four of the dancers were male and 3 were female. All had failed nonoperative treatment regimens. Five patients (5 tibias) underwent drilling and bone grafting of the lesion, and 2 patients (3 tibias) with completed fractures or multiple refractory stress fractures underwent intramedullary nailing. Clinical union was achieved at a mean of 6 weeks and radiographic union at 5.1 months. Return to full dance activity was at an average of 6.5 months postoperatively. Surgical intervention for tibial stress fractures in dancers who have not responded to nonoperative management allowed for resolution of symptoms and return to dancing with minimal morbidity.

  9. Biomechanical Factors in Tibial Stress Fracture

    DTIC Science & Technology

    2001-08-01

    Relationship between Loading Rates and Tibial Accelerometry in Forefoot Strike Runners. Presented at the Annual American Society of Biomechanics Mtg...of the APTA, Seattle, WA, 2/99. McClay, IS, Williams, DS, and Manal, KT. Lower Extremity Mechanics of Runners with a Converted Forefoot Strike ...Management, Inc, 1998-1999 The Effect of Different Orthotic Devices on Lower Extremity Mechanics of Rearfoot and Forefoot Strikers, $3,500. Foot Management

  10. The sizing of hamstring grafts for anterior cruciate reconstruction: intra- and inter-observer reliability.

    PubMed

    Dwyer, Tim; Whelan, Daniel B; Khoshbin, Amir; Wasserstein, David; Dold, Andrew; Chahal, Jaskarndip; Nauth, Aaron; Murnaghan, M Lucas; Ogilvie-Harris, Darrell J; Theodoropoulos, John S

    2015-04-01

    The objective of this study was to establish the intra- and inter-observer reliability of hamstring graft measurement using cylindrical sizing tubes. Hamstring tendons (gracilis and semitendinosus) were harvested from ten cadavers by a single surgeon and whip stitched together to create ten 4-strand hamstring grafts. Ten sports medicine surgeons and fellows sized each graft independently using either hollow cylindrical sizers or block sizers in 0.5-mm increments—the sizing technique used was applied consistently to each graft. Surgeons moved sequentially from graft to graft and measured each hamstring graft twice. Surgeons were asked to state the measured proximal (femoral) and distal (tibial) diameter of each graft, as well as the diameter of the tibial and femoral tunnels that they would drill if performing an anterior cruciate ligament (ACL) reconstruction using that graft. Reliability was established using intra-class correlation coefficients. Overall, both the inter-observer and intra-observer agreement were >0.9, demonstrating excellent reliability. The inter-observer reliability for drill sizes was also excellent (>0.9). Excellent correlation was seen between cylindrical sizing, and drill sizes (>0.9). Sizing of hamstring grafts by multiple surgeons demonstrated excellent intra-observer and intra-observer reliability, potentially validating clinical studies exploring ACL reconstruction outcomes by hamstring graft diameter when standard techniques are used. III.

  11. The role of fixation and bone quality on the mechanical stability of tibial knee components.

    PubMed

    Lee, R W; Volz, R G; Sheridan, D C

    1991-12-01

    Tibial component loosening remains one of the major causes of failure of cemented and noncemented total knee arthroplasties. In this study, the authors identified the role of implant design, method of fixation, and bone density as it related to implant stability. The physical properties of "good" and "bad" bone were simulated using a "good" and "bad" foam model of the proximal tibia, fabricated in the laboratory from DARO RF-100 foam. A generic tibial component permitting various fixation designs was implanted into "good" and "bad" variable density foam tibial models in both cemented and noncemented modes. The mechanical stability of the implants was determined using a Materials Testing Machine by the application of an eccentrically applied cyclic load. The micromotion (subsidence and lift-off) of the tibial implants was recorded using two Linear Variable Differential Transformers. Statistically significant differences in implant stability were recorded as a function of fixation method. The most rigid implant fixation was achieved using four peripherally placed, 6.5-mm cancellous screws. The addition of a central stem added stability only in the case of "poor" quality foam. The mechanical stability of noncemented implants related directly to the density of the foam. Implant stability was greatly enhanced in "poor" quality foam by the use of cement. The method of implant fixation and bone density are critical determinants to tibial implant stability.

  12. Production of EUV mask blanks with low killer defects

    NASA Astrophysics Data System (ADS)

    Antohe, Alin O.; Kearney, Patrick; Godwin, Milton; He, Long; John Kadaksham, Arun; Goodwin, Frank; Weaver, Al; Hayes, Alan; Trigg, Steve

    2014-04-01

    For full commercialization, extreme ultraviolet lithography (EUVL) technology requires the availability of EUV mask blanks that are free of defects. This remains one of the main impediments to the implementation of EUV at the 22 nm node and beyond. Consensus is building that a few small defects can be mitigated during mask patterning, but defects over 100 nm (SiO2 equivalent) in size are considered potential "killer" defects or defects large enough that the mask blank would not be usable. The current defect performance of the ion beam sputter deposition (IBD) tool will be discussed and the progress achieved to date in the reduction of large size defects will be summarized, including a description of the main sources of defects and their composition.

  13. Combined CT-based and image-free navigation systems in TKA reduces postoperative outliers of rotational alignment of the tibial component.

    PubMed

    Mitsuhashi, Shota; Akamatsu, Yasushi; Kobayashi, Hideo; Kusayama, Yoshihiro; Kumagai, Ken; Saito, Tomoyuki

    2018-02-01

    Rotational malpositioning of the tibial component can lead to poor functional outcome in TKA. Although various surgical techniques have been proposed, precise rotational placement of the tibial component was difficult to accomplish even with the use of a navigation system. The purpose of this study is to assess whether combined CT-based and image-free navigation systems replicate accurately the rotational alignment of tibial component that was preoperatively planned on CT, compared with the conventional method. We compared the number of outliers for rotational alignment of the tibial component using combined CT-based and image-free navigation systems (navigated group) with those of conventional method (conventional group). Seventy-two TKAs were performed between May 2012 and December 2014. In the navigated group, the anteroposterior axis was prepared using CT-based navigation system and the tibial component was positioned under control of the navigation. In the conventional group, the tibial component was placed with reference to the Akagi line that was determined visually. Fisher's exact probability test was performed to evaluate the results. There was a significant difference between the two groups with regard to the number of outliers: 3 outliers in the navigated group compared with 12 outliers in the conventional group (P < 0.01). We concluded that combined CT-based and image-free navigation systems decreased the number of rotational outliers of tibial component, and was helpful for the replication of the accurate rotational alignment of the tibial component that was preoperatively planned.

  14. Local application of osteoprotegerin-chitosan gel in critical-sized defects in a rabbit model

    PubMed Central

    2017-01-01

    Background Osteoprotegerin (OPG) is used for the systemic treatment of bone diseases, although it has many side effects. The aim of this study was to investigate a newly formulated OPG-chitosan gel for local application to repair bone defects. Recent studies have reported that immunodetection of osteopontin (OPN) and osteocalcin (OC) can be used to characterise osteogenesis and new bone formation. Methods The osteogenic potential of the OPG-chitosan gel was evaluated in rabbits. Critical-sized defects were created in the calvarial bone, which were either left unfilled (control; group I), or filled with chitosan gel (group II) or OPG-chitosan gel (group III), with rabbits sacrificed at 6 and 12 weeks. Bone samples from the surgical area were decalcified and treated with routine histological and immunohistochemical protocols using OC, OPN, and cathepsin K (osteoclast marker) antibodies. The toxicity of the OPG-chitosan gel was evaluated by biochemical assays (liver and kidney function tests). Results The mean bone growth in defects filled with the OPG-chitosan gel was significantly higher than those filled with the chitosan gel or the unfilled group (p < 0.05). At 6 and 12 weeks, the highest levels of OC and OPN markers were found in the OPG-chitosan gel group, followed by the chitosan gel group. The number of osteoclasts in the OPG-chitosan gel group was lower than the other groups. The results of the liver and kidney functional tests indicated no signs of harmful systemic effects of treatment. In conclusion, the OPG-chitosan gel has many characteristics that make it suitable for bone repair and regeneration, highlighting its potential benefits for tissue engineering applications. PMID:28674665

  15. What are the bias, imprecision, and limits of agreement for finding the flexion-extension plane of the knee with five tibial reference lines?

    PubMed

    Brar, Abheetinder S; Howell, Stephen M; Hull, Maury L

    2016-06-01

    Internal-external (I-E) malrotation of the tibial component is associated with poor function after total knee arthroplasty (TKA). Kinematically aligned (KA) TKA uses a functionally defined flexion-extension (F-E) tibial reference line, which is parallel to the F-E plane of the extended knee, to set I-E rotation of the tibial component. Sixty-two, three-dimensional bone models of normal knees were analyzed. We computed the bias (mean), imprecision (±standard deviation), and limits of agreement (mean±2 standard deviations) of the angle between five anatomically defined tibial reference lines used in mechanically aligned (MA) TKA and the F-E tibial reference line (+external). The following are the bias, imprecision, and limits of agreement of the angle between the F-E tibial reference line and 1) the tibial reference lines connecting the medial border (-2°±6°, -14° to 10°), medial 1/3 (6°±6°, -6° to 18°), and the most anterior point of the tibial tubercle (9°±4°, -1° to 17°) with the center of the posterior cruciate ligament, and 2) the tibial reference lines perpendicular to the posterior condylar axis of the tibia (-3°±4°, -11° to 5°), and a line connecting the centers of the tibial condyles (1°±4°, -7° to 9°). Based on these in vitro findings, it might be prudent to reconsider setting the I-E rotation of the tibial component to tibial reference lines that have bias, imprecision, and limits of agreement that fall outside the -7° to 10° range associated with high function after KA TKA. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. The quantum Ising chain with a generalized defect

    NASA Astrophysics Data System (ADS)

    Grimm, Uwe

    1990-08-01

    The finite-size scaling properties of the quantum Ising chain with different types of generalized defects are studied. This not only means an alteration of the coupling constant as previously examined, but also an additional arbitrary transformation in the algebra of observables at one site of the chain. One can distinguish between two classes of generalized defects: on the one hand those which do not affect the finite-size integrability of the Ising chain, and on the other hand those that destroy this property. In this context, finite-size integrability is always understood as a synonym for the possibility to write the hamiltonian of the finite chain as a bilinear expression in fermionic operators by means of a Jordan-Wigner transformation. Concerning the first type of defect, an exact solution for the scaling spectrum is obtained for the most universal defect that preserves the global Z2 symmetry of the chain. It is shown that in the continuum limit this yields the same result as for one properly chosen ordinary defect, that is changing the coupling constant only, and thus the finite-size scaling spectra can be described by irreps of a shifted u(1) Kac-Moody algebra. The other type of defect is examined by means of numerical finite-size calculations. In contrast to the first case, these calculations suggest a non-continuous dependence of the scaling dimensions on the defect parameters. A conjecture for the operator content involving only one primary field of a Virasoro algebra with central charge c= {1}/{2} is given.

  17. Quantitative comparison of the microscopic anatomy of the human ACL femoral and tibial entheses.

    PubMed

    Beaulieu, Mélanie L; Carey, Grace E; Schlecht, Stephen H; Wojtys, Edward M; Ashton-Miller, James A

    2015-12-01

    The femoral enthesis of the human anterior cruciate ligament (ACL) is known to be more susceptible to injury than the tibial enthesis. To determine whether anatomic differences might help explain this difference, we quantified the microscopic appearance of both entheses in 15 unembalmed knee specimens using light microscopy, toluidine blue stain and image analysis. The amount of calcified fibrocartilage and uncalcified fibrocartilage, and the ligament entheseal attachment angle were then compared between the femoral and tibial entheses via linear mixed-effects models. The results showed marked differences in anatomy between the two entheses. The femoral enthesis exhibited a 3.9-fold more acute ligament attachment angle than the tibial enthesis (p<0.001), a 43% greater calcified fibrocartilage tissue area (p<0.001), and a 226% greater uncalcified fibrocartilage depth (p<0.001), with the latter differences being particularly pronounced in the central region. We conclude that the ACL femoral enthesis has more fibrocartilage and a more acute ligament attachment angle than the tibial enthesis, which provides insight into why it is more vulnerable to failure. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  18. Severe lateral tibial bowing with short stature in two siblings--a provisionally novel syndrome.

    PubMed

    Zitano, Lia; Loder, Randall T; Cohen, Mervyn D; Weaver, David D

    2012-09-01

    In this report, we describe two siblings with short stature and severe lateral tibial bowing. In the younger sibling, the bowing was bilateral, while in the older sib, it was unilateral. However, both showed bilateral abnormalities of the distal tibial epiphyses and growth plates. Pseudoarthrosis of the left distal tibial metaphysis and subsequent spontaneous resolution of the abnormality occurred in the younger sibling. The fibulas of both children were of normal diameter and were straight, except for the distal ends. Surgery has almost completely corrected the lower leg bowing in both patients. The type of tibial bowing seen in these children can be associated with a number of syndromes, such as neurofibromatosis type I, Weismann-Netter syndrome, and a variety of environmental caused disorders, such as vitamin D deficient rickets. However, the severity of the bowing present in our patients and the absence of other clinical features differentiates this condition from those reported in the literature. We posit that the condition in the children presented here represents an as yet undescribed syndrome, which is likely to be of genetic origin. Copyright © 2012 Wiley Periodicals, Inc.

  19. "Clothesline technique" for proximal tibial shaft fracture fixation using conventional intramedullary nail: a simple, useful, and inexpensive technique to prevent fracture malalignment.

    PubMed

    Belangero, William Dias; Santos Pires, Robinson Esteves; Livani, Bruno; Rossi, Felipe Lins; de Andrade, Andre Luis Lugnani

    2018-05-01

    Treatment of proximal tibial shaft fractures is always challenging. Despite the development of modern techniques, the literature still shows high complication rates, especially regarding proximal fragment malalignment. It is well known that knee position in flexion during tibial nailing is responsible for extension and valgus deformities of the proximal fragment. Unlike in tibial shaft fractures, nails do not reduce proximal tibial fractures due to the medullary canal width. This study aims to describe a simple, useful, and inexpensive technique to prevent valgus and extension deformities when treating proximal tibial fractures using conventional nails: the so-called clothesline technique.

  20. Tibial nerve stimulation to inhibit the micturition reflex by an implantable wireless driver microstimulator in cats

    PubMed Central

    Li, Xing; Liao, Li-Min; Chen, Guo-Qing; Wang, Zhao-Xia; Lu, Tian-Ji; Deng, Han; Loeb, Gerald-E

    2016-01-01

    Abstract Background: Traditional tibial nerve stimulation (TNS) has been used to treat overactive bladder syndrome (OAB), but there are some shortcomings. Thus, a novel alternative is needed for the treatment of OAB. The study investigated the effects of a new type of tibial nerve microstimulator on the micturition reflex in cats. Methods: An implantable wireless driver microstimulator was implanted around the tibial nerve in 9 α-chloralose anesthetized cats. Cystometry was performed by infusing 0.9% normal saline (NS) or 0.25% acetic acid (AA) through a urethral catheter. Multiple cystometrograms were performed before, during, and after TNS to determine the inhibitory effect of the microstimulator on the micturition reflex. Results: TNS at 2 threshold (T) intensity significantly increased the bladder capacity (BC) during NS infusion. Bladder overactivity was irritated by the intravesical infusion of 0.25% AA, which significantly reduced the BC compared with the NS infusion. TNS at 2 T intensity suppressed AA-induced bladder overactivity and significantly increased the BC compared with the AA control. Conclusion: The implantable wireless driver tibial nerve microstimulator appears to be effective in inhibiting the micturition reflex during physiologic and pathologic conditions. The implantable wireless driver tibial nerve microstimulator could be used to treat OAB. PMID:27537576

  1. Do running speed and shoe cushioning influence impact loading and tibial shock in basketball players?

    PubMed Central

    Liebenberg, Jacobus; Woo, Jeonghyun; Park, Sang-Kyoon; Yoon, Suk-Hoon; Cheung, Roy Tsz-Hei; Ryu, Jiseon

    2018-01-01

    Background Tibial stress fracture (TSF) is a common injury in basketball players. This condition has been associated with high tibial shock and impact loading, which can be affected by running speed, footwear condition, and footstrike pattern. However, these relationships were established in runners but not in basketball players, with very little research done on impact loading and speed. Hence, this study compared tibial shock, impact loading, and foot strike pattern in basketball players running at different speeds with different shoe cushioning properties/performances. Methods Eighteen male collegiate basketball players performed straight running trials with different shoe cushioning (regular-, better-, and best-cushioning) and running speed conditions (3.0 m/s vs. 6.0 m/s) on a flat instrumented runway. Tri-axial accelerometer, force plate and motion capture system were used to determine tibial accelerations, vertical ground reaction forces and footstrike patterns in each condition, respectively. Comfort perception was indicated on a 150 mm Visual Analogue Scale. A 2 (speed) × 3 (footwear) repeated measures ANOVA was used to examine the main effects of shoe cushioning and running speeds. Results Greater tibial shock (P < 0.001; η2 = 0.80) and impact loading (P < 0.001; η2 = 0.73–0.87) were experienced at faster running speeds. Interestingly, shoes with regular-cushioning or best-cushioning resulted in greater tibial shock (P = 0.03; η2 = 0.39) and impact loading (P = 0.03; η2 = 0.38–0.68) than shoes with better-cushioning. Basketball players continued using a rearfoot strike during running, regardless of running speed and footwear cushioning conditions (P > 0.14; η2 = 0.13). Discussion There may be an optimal band of shoe cushioning for better protection against TSF. These findings may provide insights to formulate rehabilitation protocols for basketball players who are recovering from TSF. PMID:29770274

  2. [High tibial osteotomy--fixation by means of external fixation--indication, technique, complications (author's transl)].

    PubMed

    Klems, H

    1976-02-01

    High tibial osteotomy has proved its value in the treatment of gonarthrosis with or without axis deformity. The thrust of weight-bearing and other stresses is lessened on the degenerated tibial condyle and transferred to the more normal condyle. The stable fixation by means of external fixation allows early movement of the knee joint.-R-ferences to operative technique, indication, complications and after-treatment.

  3. Crystal defect studies using x-ray diffuse scattering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Larson, B.C.

    1980-01-01

    Microscopic lattice defects such as point (single atom) defects, dislocation loops, and solute precipitates are characterized by local electronic density changes at the defect sites and by distortions of the lattice structure surrounding the defects. The effect of these interruptions of the crystal lattice on the scattering of x-rays is considered in this paper, and examples are presented of the use of the diffuse scattering to study the defects. X-ray studies of self-interstitials in electron irradiated aluminum and copper are discussed in terms of the identification of the interstitial configuration. Methods for detecting the onset of point defect aggregation intomore » dislocation loops are considered and new techniques for the determination of separate size distributions for vacancy loops and interstitial loops are presented. Direct comparisons of dislocation loop measurements by x-rays with existing electron microscopy studies of dislocation loops indicate agreement for larger size loops, but x-ray measurements report higher concentrations in the smaller loop range. Methods for distinguishing between loops and three-dimensional precipitates are discussed and possibilities for detailed studies considered. A comparison of dislocation loop size distributions obtained from integral diffuse scattering measurements with those from TEM show a discrepancy in the smaller sizes similar to that described above.« less

  4. Large-size TlBr single crystal growth and defect study

    NASA Astrophysics Data System (ADS)

    Zhang, Mingzhi; Zheng, Zhiping; Chen, Zheng; Zhang, Sen; Luo, Wei; Fu, Qiuyun

    2018-04-01

    Thallium bromide (TlBr) is an attractive semiconductor material for fabrication of radiation detectors due to its high photon stopping power originating from its high atomic number, wide band gap and high resistivity. In this paper the vertical Bridgman method was used for crystal growth and TlBr single crystals with diameter of 15 mm were grown. X-ray diffraction (XRD) was used to identify phase and orientation. Electron backscatter diffraction (EBSD) was used to investigate crystal microstructure and crystallographic orientation. The optical and electric performance of the crystal was characterized by infrared (IR) transmittance spectra and I-V measurement. The types of point defects in the crystals were investigated by thermally stimulated current (TSC) spectra and positron annihilation spectroscopy (PAS). Four types of defects, with ionization energy of each defect fitting as follows: 0.1308, 0.1540, 0.3822 and 0.538 eV, were confirmed from the TSC result. The PAS result showed that there were Tl vacancies in the crystal.

  5. Effectiveness of concurrent procedures during high tibial osteotomy for medial compartment osteoarthritis: a systematic review and meta-analysis.

    PubMed

    Lee, O-Sung; Ahn, Soyeon; Ahn, Jin Hwan; Teo, Seow Hui; Lee, Yong Seuk

    2018-02-01

    The purpose of this systematic review and meta-analysis was to evaluate the efficacy of concurrent cartilage procedures during high tibial osteotomy (HTO) for medial compartment osteoarthritis (OA) by comparing the outcomes of studies that directly compared the use of HTO plus concurrent cartilage procedures versus HTO alone. Results that are possible to be compared in more than two articles were presented as forest plots. A 95% confidence interval was calculated for each effect size, and we calculated the I 2 statistic, which presents the percentage of total variation attributable to the heterogeneity among studies. The random effects model was used to calculate the effect size. Seven articles were included to the final analysis. Case groups were composed of HTO without concurrent procedures and control groups were composed of HTO with concurrent procedures such as marrow stimulation procedure, mesenchymal stem cell transplantation, and injection. The case group showed a higher hospital for special surgery score and mean difference was 4.10 [I 2 80.8%, 95% confidence interval (CI) - 9.02 to 4.82]. Mean difference of the mechanical femorotibial angle in five studies was 0.08° (I 2 0%, 95% CI - 0.26 to 0.43). However, improved arthroscopic, histologic, and MRI results were reported in the control group. Our analysis support that concurrent procedures during HTO for medial compartment OA have little beneficial effect regarding clinical and radiological outcomes. However, they might have some beneficial effects in terms of arthroscopic, histologic, and MRI findings even though the quality of healed cartilage is not good as that of original cartilage. Therefore, until now, concurrent procedures for medial compartment OA have been considered optional. Nevertheless, no conclusions can be drawn for younger patients with focal cartilage defects and concomitant varus deformity. This question needs to be addressed separately.

  6. The risk of sacrificing the PCL in cruciate retaining total knee arthroplasty and the relationship to the sagittal inclination of the tibial plateau.

    PubMed

    Sessa, Pasquale; Fioravanti, Giulio; Giannicola, Giuseppe; Cinotti, Gianluca

    2015-01-01

    In cruciate retaining total knee arthroplasty (TKA), a partial avulsion of PCL may occur when en-bloc tibial osteotomy is performed. We evaluated the effects of a tibial cut performed with different degrees of posterior slope on PCL insertion and whether the results are affected by the sagittal inclination of the patient's tibial plateau. We selected 83 MRIs of knees showing mild or no degenerative changes. The effects of a simulated tibial cut performed with a posterior slope of 0°, 3°, 5° and parallel to the patient's tibial plateau inclination on PCL insertion in the proximal tibia were investigated. The results were correlated with the degree of posterior inclination of the tibial plateau. Every angle we used for the tibial cut caused a PCL avulsion greater than 50%. The percentage of PCL avulsion significantly increased with increasing the posterior slope of the tibial cut. Patients with sagittal tibial plateau inclination <5° showed greater PCL avulsion than those with sagittal inclination >8°. Most of the PCL insertion is likely to be sacrificed when resection of the proximal tibia is performed en-block. The risk of PCL avulsion is reduced in patients showing a marked posterior inclination of the tibial plateau, but even in this group of patients a surgical technique aimed at sparing most of the PCL insertion is necessary. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Comparison of fixed-bearing and mobile-bearing total knee arthroplasty after high tibial osteotomy.

    PubMed

    Hernigou, Philippe; Huys, Maxime; Pariat, Jacques; Roubineau, François; Flouzat Lachaniette, Charles Henri; Dubory, Arnaud

    2018-02-01

    There is no information comparing the results of fixed-bearing total knee replacement and mobile-bearing total knee replacement in the same patients previously treated by high tibial osteotomy. The purpose was therefore to compare fixed-bearing and mobile-bearing total knee replacements in patients treated with previous high tibial osteotomy. We compared the results of 57 patients with osteoarthritis who had received a fixed-bearing prosthesis after high tibial osteotomy with the results of 41 matched patients who had received a rotating platform after high tibial osteotomy. The match was made for length of follow-up period. The mean follow-up was 17 years (range, 15-20 years). The patients were assessed clinically and radiographically. The pre-operative knee scores had no statistically significant differences between the two groups. So was the case with the intra-operative releases, blood loss, thromboembolic complications and infection rates in either group. There was significant improvement in both groups of knees, and no significant difference was observed between the groups (i.e., fixed-bearing and mobile-bearing knees) for the mean Knee Society knee clinical score (95 and 92 points, respectively), or the Knee Society knee functional score (82 and 83 points, respectively) at the latest follow-up. However, the mean post-operative knee motion was higher for the fixed-bearing group (117° versus 110°). In the fixed-bearing group, one knee was revised because of periprosthetic fracture. In the rotating platform mobile-bearing group, one knee was revised because of aseptic loosening of the tibial component. The Kaplan-Meier survivorship for revision at ten years of follow-up was 95.2% for the fixed bearing prosthesis and 91.1% for the rotating platform mobile-bearing prosthesis. Although we did manage to detect significant differences mainly in clinical and radiographic results between the two groups, we found no superiority or inferiority of the mobile

  8. Do Tibial Plateau Fractures Worsen Outcomes of Knee Ligament Injuries? A Matched Cohort Analysis

    PubMed Central

    Cinque, Mark E.; Godin, Jonathan A.; Moatshe, Gilbert; Chahla, Jorge; Kruckeberg, Bradley M.; Pogorzelski, Jonas; LaPrade, Robert F.

    2017-01-01

    Background: Tibial plateau fractures account for a small portion of all fractures; however, these fractures can pose a surgical challenge when occurring concomitantly with ligament injuries. Purpose/Hypothesis: The purpose of this study was to compare 2-year outcomes of soft tissue reconstruction with or without a concomitant tibial plateau fracture and open reduction internal fixation. We hypothesized that patients with a concomitant tibial plateau fracture at the time of soft tissue surgery would have inferior outcomes compared with patients without an associated tibial plateau fracture. Study Design: Cohort study; Level of evidence, 3. Methods: Forty patients were included in this study: 8 in the fracture group and 32 in the matched control group. Inclusion criteria for the fracture group included patients who were at least 18 years old at the time of surgery and sustained a tibial plateau fracture and a concomitant injury of the anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament, or fibular collateral ligament in isolation or any combination of cruciate or collateral ligaments and who subsequently underwent isolated or combined ligament reconstruction. Patients were excluded if they underwent prior ipsilateral knee surgery, sustained additional bony injuries, or sustained an isolated extra-articular ligament injury at the time of injury. Each patient with a fracture was matched with 4 patients from a control group who had no evidence of a tibial plateau fracture but underwent the same soft tissue reconstruction procedure. Results: Patients in the fracture group improved significantly from preoperatively to postoperatively with respect to Short Form–12 (P < .05) and Western Ontario and McMaster Universities Osteoarthritis Index total scores (P < .05). The Lysholm (P = .075) and Tegner scores (P = .086) also improved, although this was not statistically significant. Patients in the control group improved significantly from

  9. Achilles lengthening/posterior tibial tenotomy with immediate weightbearing for patients with significant comorbidities.

    PubMed

    Redfern, John C; Thordarson, David B

    2008-03-01

    Fixed equinovarus deformities can be challenging to treat especially in medically debilitated patients. The purpose of this study was to evaluate Achilles lengthening with posterior tibial tenotomy and immediate weightbearing in this difficult group of patients. Thirteen extremities in 10 patients underwent Achilles lengthening and posterior tibial tenotomy for fixed equinovarus deformities with significant medical comorbidities. Pre- and postoperative ambulatory status and deformities were noted. Average age at the time of surgery was 65 with an average duration of deformity 6.3 years. The average equinus corrected from 26 degrees to 1.2 degrees and the average varus deformity improved from -8.5 degrees to 2.7 degrees. All patients except one who was wheelchair-bound had a significant improvement in ambulatory status. Achilles lengthening with posterior tibial tenotomy allowed for immediate postoperative weightbearing with improvement in deformity and ambulatory status in this complicated patient group.

  10. Chronic exertional compartment syndrome with medial tibial stress syndrome in twins.

    PubMed

    Banerjee, Purnajyoti; McLean, Christopher

    2011-06-14

    Chronic exertional compartment syndrome and medial tibial stress syndrome are uncommon conditions that affect long-distance runners or players involved in team sports that require extensive running. We report 2 cases of bilateral chronic exertional compartment syndrome, with medial tibial stress syndrome in identical twins diagnosed with the use of a Kodiag monitor (B. Braun Medical, Sheffield, United Kingdom) fulfilling the modified diagnostic criteria for chronic exertional compartment syndrome as described by Pedowitz et al, which includes: (1) pre-exercise compartment pressure level >15 mm Hg; (2) 1 minute post-exercise pressure >30 mm Hg; and (3) 5 minutes post-exercise pressure >20 mm Hg in the presence of clinical features. Both patients were treated with bilateral anterior fasciotomies through minimal incision and deep posterior fasciotomies with tibial periosteal stripping performed through longer anteromedial incisions under direct vision followed by intensive physiotherapy resulting in complete symptomatic recovery. The etiology of chronic exertional compartment syndrome is not fully understood, but it is postulated abnormal increases in intramuscular pressure during exercise impair local perfusion, causing ischemic muscle pain. No familial predisposition has been reported to date. However, some authors have found that no significant difference exists in the relative perfusion, in patients, diagnosed with chronic exertional compartment syndrome. Magnetic resonance images of affected compartments have indicated that the pain is not due to ischemia, but rather from a disproportionate oxygen supply versus demand. We believe this is the first report of chronic exertional compartment syndrome with medial tibial stress syndrome in twins, raising the question of whether there is a genetic predisposition to the causation of these conditions. Copyright 2011, SLACK Incorporated.

  11. Discriminant Analysis of Defective and Non-Defective Field Pea (Pisum sativum L.) into Broad Market Grades Based on Digital Image Features.

    PubMed

    McDonald, Linda S; Panozzo, Joseph F; Salisbury, Phillip A; Ford, Rebecca

    2016-01-01

    Field peas (Pisum sativum L.) are generally traded based on seed appearance, which subjectively defines broad market-grades. In this study, we developed an objective Linear Discriminant Analysis (LDA) model to classify market grades of field peas based on seed colour, shape and size traits extracted from digital images. Seeds were imaged in a high-throughput system consisting of a camera and laser positioned over a conveyor belt. Six colour intensity digital images were captured (under 405, 470, 530, 590, 660 and 850nm light) for each seed, and surface height was measured at each pixel by laser. Colour, shape and size traits were compiled across all seed in each sample to determine the median trait values. Defective and non-defective seed samples were used to calibrate and validate the model. Colour components were sufficient to correctly classify all non-defective seed samples into correct market grades. Defective samples required a combination of colour, shape and size traits to achieve 87% and 77% accuracy in market grade classification of calibration and validation sample-sets respectively. Following these results, we used the same colour, shape and size traits to develop an LDA model which correctly classified over 97% of all validation samples as defective or non-defective.

  12. Discriminant Analysis of Defective and Non-Defective Field Pea (Pisum sativum L.) into Broad Market Grades Based on Digital Image Features

    PubMed Central

    McDonald, Linda S.; Panozzo, Joseph F.; Salisbury, Phillip A.; Ford, Rebecca

    2016-01-01

    Field peas (Pisum sativum L.) are generally traded based on seed appearance, which subjectively defines broad market-grades. In this study, we developed an objective Linear Discriminant Analysis (LDA) model to classify market grades of field peas based on seed colour, shape and size traits extracted from digital images. Seeds were imaged in a high-throughput system consisting of a camera and laser positioned over a conveyor belt. Six colour intensity digital images were captured (under 405, 470, 530, 590, 660 and 850nm light) for each seed, and surface height was measured at each pixel by laser. Colour, shape and size traits were compiled across all seed in each sample to determine the median trait values. Defective and non-defective seed samples were used to calibrate and validate the model. Colour components were sufficient to correctly classify all non-defective seed samples into correct market grades. Defective samples required a combination of colour, shape and size traits to achieve 87% and 77% accuracy in market grade classification of calibration and validation sample-sets respectively. Following these results, we used the same colour, shape and size traits to develop an LDA model which correctly classified over 97% of all validation samples as defective or non-defective. PMID:27176469

  13. Assessment of tibial rotation and meniscal movement using kinematic magnetic resonance imaging

    PubMed Central

    2014-01-01

    Objective This work aimed to assess tibial rotations, meniscal movements, and morphological changes during knee flexion and extension using kinematic magnetic resonance imaging (MRI). Methods Thirty volunteers with healthy knees were examined using kinematic MRI. The knees were imaged in the transverse plane with flexion and extension angles from 0° to 40° and 40° to 0°, respectively. The tibial interior and exterior rotation angles were measured, and the meniscal movement range, height change, and side movements were detected. Results The tibia rotated internally (11.55° ± 3.20°) during knee flexion and rotated externally (11.40° ± 3.0°) during knee extension. No significant differences were observed between the internal and external tibial rotation angles (P > 0.05), between males and females (P > 0.05), or between the left and right knee joints (P > 0.05). The tibial rotation angle with a flexion angle of 0° to 24° differed significantly from that with a flexion angle of 24° to 40° (P < 0.01). With knee flexion, the medial and lateral menisci moved backward and the height of the meniscus increased. The movement range was greater in the anterior horn than in the posterior horn and greater in the lateral meniscus than in the medial meniscus (P < 0.01). During backward movements of the menisci, the distance between the anterior and posterior horns decreased, with the decrease more apparent in the lateral meniscus (P < 0.01). The side movements of the medial and lateral menisci were not obvious, and a smaller movement range was found than that of the forward and backward movements. Conclusion Knee flexion and extension facilitated internal and external tibial rotations, which may be related to the ligament and joint capsule structure and femoral condyle geometry. PMID:25142267

  14. The Impact of Computed Tomography on Decision Making in Tibial Plateau Fractures.

    PubMed

    Castiglia, Marcello Teixeira; Nogueira-Barbosa, Marcello Henrique; Messias, Andre Marcio Vieira; Salim, Rodrigo; Fogagnolo, Fabricio; Schatzker, Joseph; Kfuri, Mauricio

    2018-02-14

    Schatzker introduced one of the most used classification systems for tibial plateau fractures, based on plain radiographs. Computed tomography brought to attention the importance of coronal plane-oriented fractures. The goal of our study was to determine if the addition of computed tomography would affect the decision making of surgeons who usually use the Schatzker classification to assess tibial plateau fractures. Image studies of 70 patients who sustained tibial plateau fractures were uploaded to a dedicated homepage. Every patient was linked to a folder which contained two radiographic projections (anteroposterior and lateral), three interactive videos of computed tomography (axial, sagittal, and coronal), and eight pictures depicting tridimensional reconstructions of the tibial plateau. Ten attending orthopaedic surgeons, who were blinded to the cases, were granted access to the homepage and assessed each set of images in two different rounds, separated to each other by an interval of 2 weeks. Each case was evaluated in three steps, where surgeons had access, respectively to radiographs, two-dimensional videos of computed tomography, and three-dimensional reconstruction images. After every step, surgeons were asked to present how would they classify the case using the Schatzker system and which surgical approaches would be appropriate. We evaluated the inter- and intraobserver reliability of the Schatzker classification using the Kappa concordance coefficient, as well as the impact of computed tomography in the decision making regarding the surgical approach for each case, by using the chi-square test and likelihood ratio. The interobserver concordance kappa coefficients after each assessment step were, respectively, 0.58, 0.62, and 0.64. For the intraobserver analysis, the coefficients were, respectively, 0.76, 0.75, and 0.78. Computed tomography changed the surgical approach selection for the types II, V, and VI of Schatzker ( p  < 0.01). The addition of

  15. Tibial slope correction combined with second revision ACL produces good knee stability and prevents graft rupture.

    PubMed

    Dejour, David; Saffarini, Mo; Demey, Guillaume; Baverel, Laurent

    2015-10-01

    Revision ACL reconstruction requires careful analysis of failure causes particularly in cases of two previous graft ruptures. Intrinsic factors as excessive tibial slope or narrow femoral notch increase failure risks but are rarely addressed in revision surgery. The authors report outcomes, at minimum follow-up of 2 years, for second revision ACL reconstructions combined with tibial deflexion osteotomy for correction of excessive slope (>12°). Nine patients that underwent second revision ACL reconstruction combined with tibial deflexion osteotomy were retrospectively studied. The mean age was 30.3 ± 4.4 years (median 28; range 26-37), and mean follow-up was 4.0 ± 2.0 years (median 3.6; range 2.0-7.6). Autografts were harvested from the quadriceps tendon (n = 8) or hamstrings (n = 1), and tibial osteotomy was done by anterior closing wedge, without detachment of the patellar tendon, to obtain a slope of 3° to 5°. All patients had fused osteotomies, stable knees, and there were no intraoperative or postoperative complications. The mean posterior tibial slope decreased from 13.2° ± 2.6° (median 13°; range 12°-18°) preoperatively to 4.4° ± 2.3° (median 4°; range 2°-8°) postoperatively. The mean Lysholm score was 73.8 ± 5.8 (median 74; range 65-82), and the IKDC-SKF was 71.6 ± 6.1 (median 72.8; range 62.2-78.5). The satisfactory results of second revision ACL reconstruction combined with tibial deflexion osteotomy at minimum follow-up of 2 years suggest that tibia slope correction protects reconstructed ACL from fatigue failure in this study. The authors stress the importance of careful analysis failure causes prior to revision ACL reconstruction, and recommend correction of tibial slope if it exceeds 12°, to reduce the risks of graft retear. III.

  16. SEMATECH produces defect-free EUV mask blanks: defect yield and immediate challenges

    NASA Astrophysics Data System (ADS)

    Antohe, Alin O.; Balachandran, Dave; He, Long; Kearney, Patrick; Karumuri, Anil; Goodwin, Frank; Cummings, Kevin

    2015-03-01

    Availability of defect-free reflective mask has been one of the most critical challenges to extreme ultraviolet lithography (EUVL). To mitigate the risk, significant progress has been made on defect detection, pattern shifting, and defect repair. Clearly such mitigation strategies are based on the assumption that defect counts and sizes from incoming mask blanks must be below practical levels depending on mask specifics. The leading industry consensus for early mask product development is that there should be no defects greater than 80 nm in the quality area, 132 mm x 132 mm. In addition less than 10 defects smaller than 80 nm may be mitigable. SEMATECH has been focused on EUV mask blank defect reduction using Veeco Nexus TM IBD platform, the industry standard for mask blank production, and assessing if IBD technology can be evolved to a manufacturing solution. SEMATECH has recently announced a breakthrough reduction of defects in the mask blank deposition process resulting in the production of two defect-free EUV mask blanks at 54 nm inspection sensitivity (SiO2 equivalent). This paper will discuss the dramatic reduction of baseline EUV mask blank defects, review the current deposition process run and compare results with previous process runs. Likely causes of remaining defects will be discussed based on analyses as characterized by their compositions and whether defects are embedded in the multilayer stack or non-embedded.

  17. Location of the tibial tunnel aperture affects extrusion of the lateral meniscus following reconstruction of the anterior cruciate ligament.

    PubMed

    Kodama, Yuya; Furumatsu, Takayuki; Miyazawa, Shinichi; Fujii, Masataka; Tanaka, Takaaki; Inoue, Hiroto; Ozaki, Toshifumi

    2017-08-01

    The anterior root of the lateral meniscus provides functional stability to the meniscus. In this study, we evaluated the relationship between the position of the tibial tunnel and extrusion of the lateral meniscus after anterior cruciate ligament reconstruction, where extrusion provides a proxy measure of injury to the anterior root. The relationship between extrusion and tibial tunnel location was retrospectively evaluated from computed tomography and magnetic resonance images of 26 reconstructed knees, contributed by 25 patients aged 17-31 years. A measurement grid was used to localize the position of the tibial tunnel based on anatomical landmarks identified from the three-dimensional reconstruction of axial computed tomography images of the tibial plateaus. The reference point-to-tibial tunnel distance (mm) was defined as the distance from the midpoint of the lateral edge of the grid to the posterolateral aspect of the tunnel aperture. The optimal cutoff of this distance to minimize post-operative extrusion was identified using receiver operating curve analysis. Extrusion of the lateral meniscus was positively correlated to the reference point-to-tibial tunnel distance (r 2  = 0.64; p < 0.001), with a cutoff distance of 5 mm having a sensitivity to extrusion of 83% and specificity of 93%. The mean extrusion for a distance >5 mm was 0.40 ± 0.43 mm, compared to 1.40 ± 0.51 mm for a distance ≤5 mm (p < 0.001). Therefore, a posterolateral location of the tibial tunnel aperture within the footprint of the anterior cruciate ligament decreases the reference point-to-tibial tunnel distance and increases extrusion of the lateral meniscus post-reconstruction. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1625-1633, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  18. The study of develop optimization to control various resist defect in Photomask fabrication

    NASA Astrophysics Data System (ADS)

    Lim, JongHoon; Kim, ByungJu; Son, JaeSik; Park, EuiSang; Kim, SangPyo; Yim, DongGyu

    2015-07-01

    To reduce the pattern size in photomask is an inevitable trend because of the minimization of chip size. So it makes a big challenge to control defects in photomask industry. Defects below a certain size that had not been any problem in previous technology node are becoming an issue as the patterns are smaller. Therefore, the acceptable tolerance levels for current defect size and quantity are dramatically reduced. Because these defects on photomask can be the sources of the repeating defects on wafer, small size defects smaller than 200nm should not be ignored any more. Generally, almost defects are generated during develop process and etch process. Especially it is difficult to find the root cause of defects formed during the develop process because of their various types and very small size. In this paper, we studied how these small defects can be eliminated by analyzing the defects and tuning the develop process. There are 3 types of resist defects which are named as follows. The first type is `Popcorn' defect which is mainly occurred in negative resist and exists on the dark features. The second type is `Frog eggs' defect which is occurred in 2nd process of HTPSM and exists on the wide space area. The last type is `Spot' defect which also exists on the wide space area. These defects are generally appeared on the entire area of a plate and the number of these defects is about several hundred. It is thought that the original source is the surface's hydrophilic state before develop process or the incongruity between resist and developer. This study shows that the optimizing the develop process can be a good solution for some resist defects.

  19. Posterior Tibial Slope Angle Correlates With Peak Sagittal and Frontal Plane Knee Joint Loading During Robotic Simulations of Athletic Tasks.

    PubMed

    Bates, Nathaniel A; Nesbitt, Rebecca J; Shearn, Jason T; Myer, Gregory D; Hewett, Timothy E

    2016-07-01

    Tibial slope angle is a nonmodifiable risk factor for anterior cruciate ligament (ACL) injury. However, the mechanical role of varying tibial slopes during athletic tasks has yet to be clinically quantified. To examine the influence of posterior tibial slope on knee joint loading during controlled, in vitro simulation of the knee joint articulations during athletic tasks. Descriptive laboratory study. A 6 degree of freedom robotic manipulator positionally maneuvered cadaveric knee joints from 12 unique specimens with varying tibial slopes (range, -7.7° to 7.7°) through drop vertical jump and sidestep cutting tasks that were derived from 3-dimensional in vivo motion recordings. Internal knee joint torques and forces were recorded throughout simulation and were linearly correlated with tibial slope. The mean (±SD) posterior tibial slope angle was 2.2° ± 4.3° in the lateral compartment and 2.3° ± 3.3° in the medial compartment. For simulated drop vertical jumps, lateral compartment tibial slope angle expressed moderate, direct correlations with peak internally generated knee adduction (r = 0.60-0.65), flexion (r = 0.64-0.66), lateral (r = 0.57-0.69), and external rotation torques (r = 0.47-0.72) as well as inverse correlations with peak abduction (r = -0.42 to -0.61) and internal rotation torques (r = -0.39 to -0.79). Only frontal plane torques were correlated during sidestep cutting simulations. For simulated drop vertical jumps, medial compartment tibial slope angle expressed moderate, direct correlations with peak internally generated knee flexion torque (r = 0.64-0.69) and lateral knee force (r = 0.55-0.74) as well as inverse correlations with peak external torque (r = -0.34 to -0.67) and medial knee force (r = -0.58 to -0.59). These moderate correlations were also present during simulated sidestep cutting. The investigation supported the theory that increased posterior tibial slope would lead to greater magnitude knee joint moments, specifically

  20. An approach to detecting deliberately introduced defects and micro-defects in 3D printed objects

    NASA Astrophysics Data System (ADS)

    Straub, Jeremy

    2017-05-01

    In prior work, Zeltmann, et al. demonstrated the negative impact that can be created by defects of various sizes in 3D printed objects. These defects may make the object unsuitable for its application or even present a hazard, if the object is being used for a safety-critical application. With the uses of 3D printing proliferating and consumer access to printers increasing, the desire of a nefarious individual or group to subvert the desired printing quality and safety attributes of a printer or printed object must be considered. Several different approaches to subversion may exist. Attackers may physically impair the functionality of the printer or launch a cyber-attack. Detecting introduced defects, from either attack, is critical to maintaining public trust in 3D printed objects and the technology. This paper presents an alternate approach. It applies a quality assurance technology based on visible light sensing to this challenge and assesses its capability for detecting introduced defects of multiple sizes.

  1. Arthroscopic pullout repair of a complete radial tear of the tibial attachment site of the medial meniscus posterior horn.

    PubMed

    Kim, Young-Mo; Rhee, Kwang-Jin; Lee, June-Kyu; Hwang, Deuk-Soo; Yang, Jun-Young; Kim, Sung-Jae

    2006-07-01

    We developed an effective arthroscopic pullout technique for repairing complete radial tears of the tibial attachment site of the medial meniscus posterior horn (MMPH). In our technique, the torn meniscus is reattached to the tibial plateau immediately medial or anteromedial to the posterior cruciate ligament (PCL) using two No. 2 Ethibond sutures (Ethicon, Somerville, NJ). After a complete radial tear of the tibial attachment site of the MMPH and its reparability were confirmed, using a Caspari suture loaded with a suture shuttle, one No. 2 Ethibond suture is placed through the meniscus, through the red-red zone, 3 to 5 mm medial to the torn edge of the MMPH, and the other is passed through the meniscocapsular junction 3 to 5 mm medial to the torn edge of the meniscus. Then, a tibial tunnel, 5-mm in diameter, is made from the anteromedial aspect of the proximal tibia to the previously prepared tibial plateau, immediately medial or anteromedial to the PCL, and the two No. 2 Ethibond sutures are pulled out through the tibial tunnel and then fixed to the proximal tibia using a 3.5-mm cortical screw and washer. Firm reattachment of the torn meniscus was confirmed arthroscopically.

  2. Total Knee Arthroplasty for Osteoarthritis Secondary to Fracture of the Tibial Plateau. A Prospective Matched Cohort Study.

    PubMed

    Lizaur-Utrilla, Alejandro; Collados-Maestre, Isabel; Miralles-Muñoz, Francisco A; Lopez-Prats, Fernando A

    2015-08-01

    A prospective matched cohort study was performed to compare outcomes of total knee arthroplasties (TKA) between 29 patients with posttraumatic osteoarthritis (POA) after a fracture of tibial plateau and 58 patients underwent routine TKA. Mean follow-up was 6.7 years. There were no significant differences in KSS, WOMAC, SF12 scores or range of motion. In the control group there were no complications. In the posttraumatic group, complications occurred in 4 patients (13.7%) (P=0.010) including partial patellar tendon detachment, superficial infection, skin necrosis, and knee stiffness. Only this last patient required revision for manipulation under anesthesia. Also, there was a revision for tibial aseptic loosening in each group. TKA is an effective treatment for POA after tibial plateau fracture. We recommend the prior removal of hardware, as well as tibial tubercle osteotomy when necessary. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Characterization technique for detection of atom-size crystalline defects and strains using two-dimensional fast-Fourier-transform sampling Moiré method

    NASA Astrophysics Data System (ADS)

    Kodera, Masako; Wang, Qinghua; Ri, Shien; Tsuda, Hiroshi; Yoshioka, Akira; Sugiyama, Toru; Hamamoto, Takeshi; Miyashita, Naoto

    2018-04-01

    Recently, we have developed a two-dimensional (2D) fast-Fourier-transform (FFT) sampling Moiré technique to visually and quantitatively determine the locations of minute defects in a transmission electron microscopy (TEM) image. We applied this technique for defect detection with GaN high electron mobility transistor (HEMT) devices, and successfully and clearly visualized atom-size defects in AlGaN/GaN crystalline structures. The defect density obtained in the AlGaN/GaN structures is ∼1013 counts/cm2. In addition, we have successfully confirmed that the distribution and number of defects closely depend on the process conditions. Thus, this technique is quite useful for a device development. Moreover, the strain fields in an AlGaN/GaN crystal were effectively calculated with nm-scale resolution using this method. We also demonstrated that this sampling Moiré technique is applicable to silicon devices, which have principal directions different from those of AlGaN/GaN crystals. As a result, we believe that the 2D FFT sampling Moiré method has great potential applications to the discovery of new as yet unknown phenomena occurring between the characteristics of a crystalline material and device performance.

  4. The use of a robotic tibial rotation device and an electromagnetic tracking system to accurately reproduce the clinical dial test.

    PubMed

    Stinton, S K; Siebold, R; Freedberg, H; Jacobs, C; Branch, T P

    2016-03-01

    The purpose of this study was to: (1) determine whether a robotic tibial rotation device and an electromagnetic tracking system could accurately reproduce the clinical dial test at 30° of knee flexion; (2) compare rotation data captured at the footplates of the robotic device to tibial rotation data measured using an electromagnetic sensor on the proximal tibia. Thirty-two unilateral ACL-reconstructed patients were examined using a robotic tibial rotation device that mimicked the dial test. The data reported in this study is only from the healthy legs of these patients. Torque was applied through footplates and was measured using servomotors. Lower leg motion was measured at the foot using the motors. Tibial motion was also measured through an electromagnetic tracking system and a sensor on the proximal tibia. Load-deformation curves representing rotational motion of the foot and tibia were compared using Pearson's correlation coefficients. Off-axis motions including medial-lateral translation and anterior-posterior translation were also measured using the electromagnetic system. The robotic device and electromagnetic system were able to provide axial rotation data and translational data for the tibia during the dial test. Motion measured at the foot was not correlated to motion of the tibial tubercle in internal rotation or in external rotation. The position of the tibial tubercle was 26.9° ± 11.6° more internally rotated than the foot at torque 0 Nm. Medial-lateral translation and anterior-posterior translation were combined to show the path of the tubercle in the coronal plane during tibial rotation. The information captured during a manual dial test includes both rotation of the tibia and proximal tibia translation. All of this information can be captured using a robotic tibial axial rotation device with an electromagnetic tracking system. The pathway of the tibial tubercle during tibial axial rotation can provide additional information about knee

  5. Assessment of bone repair in critical-size defect in the calvarium of rats after the implantation of tricalcium phosphate beta (β-TCP).

    PubMed

    de Freitas Silva, Leonardo; de Carvalho Reis, Erik Neiva Ribeiro; Barbara, Tânia Aparecida; Bonardi, João Paulo; Garcia, Idelmo Rangel; de Carvalho, Paulo Sérgio Perri; Ponzoni, Daniela

    2017-07-01

    Evaluating the osteoconductive property of tricalcium phosphate beta (β-TCP) in comparison to that of inorganic bovine bone for repair in a critical-size defect in the rat calvarium. Critical-size defects of 7mm were made with a trephine in the calvaria of 48 Wistar rats. The animals were divided into four groups, and the defects in each group were filled with tricalcium phosphate beta (β-TCP), inorganic bovine bone (Bio-Oss), autogenous bone, or left empty. The animals were euthanized at two different time points (30 and 60days post-operation). All defects were recovered with a absorbable membrane of bovine cortical bone. Histological, histometric, and immunohistochemical (osteocalcin) assessments were carried out at 30 and 60days post-operation. At 30days post-operation, all groups showed areas of bone formation, predominantly when autogenous grafts were used. However, there were no statistically significant differences between the treatment groups (p>0.05). After 60days, there were similarities in the bone formation patterns between the β-TCP (26.32±) and Bio-Oss (17.35±) groups (p=0.549). In terms of the immunohistochemical assessment of osteocalcin, the clot group showed light to moderate staining at 30 and 60days. The autogenous group showed moderate staining at 30days and moderate to intense staining after 60days. The Bio-Oss group showed light to moderate staining after 30days and intense staining at 60days. The β-TCP group showed moderate staining at 30 and 60days post-operation. β-TCP is a good osteoconductive material with similar effects to those of inorganic bovine bone graft and is suitable for utilization in the repair of bone defects. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Radiologic assessment of femoral and tibial tunnel placement based on anatomic landmarks in arthroscopic single bundle anterior cruciate ligament reconstruction.

    PubMed

    Nema, Sandeep Kumar; Balaji, Gopisankar; Akkilagunta, Sujiv; Menon, Jagdish; Poduval, Murali; Patro, Dilip

    2017-01-01

    Accurate tibial and femoral tunnel placement has a significant effect on outcomes after anterior cruciate ligament reconstruction (ACLR). Postoperative radiographs provide a reliable and valid way for the assessment of anatomical tunnel placement after ACLR. The aim of this study was to examine the radiographic location of tibial and femoral tunnels in patients who underwent arthroscopic ACLR using anatomic landmarks. Patients who underwent arthroscopic ACLR from January 2014 to March 2016 were included in this retrospective cohort study. 45 patients who underwent arthroscopic ACLR, postoperative radiographs were studied. Femoral and tibial tunnel positions on sagittal and coronal radiographic views, graft impingement, and femoral roof angle were measured. Radiological parameters were summarized as mean ± standard deviation and proportions as applicable. Interobserver agreement was measured using intraclass correlation coefficient. The position of the tibial tunnel was found to be at an average of 35.1% ± 7.4% posterior from the anterior edge of the tibia. The femoral tunnel was found at an average of 30% ± 1% anterior to the posterior femoral cortex along the Blumensaat's line. Radiographic impingement was found in 34% of the patients. The roof angle averaged 34.3° ± 4.3°. The position of the tibial tunnel was found at an average of 44.16% ± 3.98% from the medial edge of the tibial plateau. The coronal tibial tunnel angle averaged 67.5° ± 8.9°. The coronal angle of the femoral tunnel averaged 41.9° ± 8.5°. The femoral and tibial tunnel placements correlated well with anatomic landmarks except for radiographic impingement which was present in 34% of the patients.

  7. Functional reconstruction of critical-sized load-bearing bone defects using a Sclerostin-targeting miR-210-3p-based construct to enhance osteogenic activity.

    PubMed

    Hu, Bin; Li, Yan; Wang, Mohan; Zhu, Youming; Zhou, Yong; Sui, Baiyan; Tan, Yu; Ning, Yujie; Wang, Jie; He, Jiacai; Yang, Chi; Zou, Duohong

    2018-06-10

    A considerable amount of research has focused on improving regenerative therapy strategies for repairing defects in load-bearing bones. The enhancement of tissue regeneration with microRNAs (miRNAs) is being developed because miRNAs can simultaneously regulate multiple signaling pathways in an endogenous manner. In this study, we developed a miR-210-based bone repair strategy. We identified a miRNA (miR-210-3p) that can simultaneously up-regulate the expression of multiple key osteogenic genes in vitro. This process resulted in enhanced bone formation in a subcutaneous mouse model with a miR-210-3p/poly-L-lactic acid (PLLA)/bone marrow-derived stem cell (BMSC) construct. Furthermore, we constructed a model of critical-sized load-bearing bone defects and implanted a miR-210-3p/β-tricalcium phosphate (β-TCP)/bone mesenchymal stem cell (BMSC) construct into the defect. We found that the load-bearing defect was almost fully repaired using the miR-210-3p construct. We also identified a new mechanism by which miR-210-3p regulates Sclerostin protein levels. This miRNA-based strategy may yield novel therapeutic methods for the treatment of regenerative defects in vital load-bearing bones by utilizing miRNA therapy for tissue engineering. The destroyed maxillofacial bone reconstruction is still a real challenge for maxillofacial surgeon, due to that functional bone reconstruction involved load-bearing. Base on the above problem, this paper developed a novel miR-210-3p/β-tricalcium phosphate (TCP)/bone marrow-derived stem cell (BMSC) construct (miR-210-3p/β-TCP/BMSCs), which lead to functional reconstruction of critical-size mandible bone defect. We found that the load-bearing defect was almost fully repaired using the miR-210-3p construct. In addition, we also found the mechanism of how the delivered microRNA activated the signaling pathways of endogenous stem cells, leading to the defect regeneration. This miRNA-based strategy can be used to regenerate defects in vital

  8. Improving Soldier Recovery from Catastrophic Bone Injuries: Developing an Animal Model for Standarizing the Bone Reparative Potential of Emerging Progenitor Cell Therapies

    DTIC Science & Technology

    2008-08-01

    To better understand the cellular basis of a long bone defect, we have utilized the GFP reporters in the closed tibial fracture. The surprise finding...callus. In the coming year we will apply the information learned from the calvarial defect to a non-union extension of the tibial fracture model...initiated a comprehensive examination of the tibial fracture model in mice bearing GFP reporters of lineage progression. This project has been assumed

  9. Elastomeric enriched biodegradable polyurethane sponges for critical bone defects: a successful case study reducing donor site morbidity.

    PubMed

    Lavrador, Catarina; Mascarenhas, Ramiro; Coelho, Paulo; Brites, Cláudia; Pereira, Alfredo; Gogolewski, Sylwester

    2016-03-01

    Bone substitutes have been a critical issue as the natural source can seldom provide enough bone to support full healing. No bone substitute complies with all necessary functions and characteristics that an autograft does. Polyurethane sponges have been used as a surgical alternative to cancellous bone grafts for critical bone defect donor sites. Critical bone defects were created on the tibial tuberosity and iliac crest using an ovine model. In group I (control-untreated), no bone regeneration was observed in any animal. In group II (defects left empty but covered with a microporous polymeric membrane), the new bone bridged the top ends in all animals. In groups III and IV, bone defects were implanted with polyurethane scaffolds modified with biologically active compounds, and bone regeneration was more efficient than in group II. In groups III and IV there were higher values of bone regeneration specific parameters used for evaluation (P < 0.05) although the comparison between these groups was not possible. The results obtained in this study suggest that biodegradable polyurethane substitutes modified with biologically active substances may offer an alternative to bone graft, reducing donor site morbidity associated with autogenous cancellous bone harvesting.

  10. Automatic thermographic image defect detection of composites

    NASA Astrophysics Data System (ADS)

    Luo, Bin; Liebenberg, Bjorn; Raymont, Jeff; Santospirito, SP

    2011-05-01

    Detecting defects, and especially reliably measuring defect sizes, are critical objectives in automatic NDT defect detection applications. In this work, the Sentence software is proposed for the analysis of pulsed thermography and near IR images of composite materials. Furthermore, the Sentence software delivers an end-to-end, user friendly platform for engineers to perform complete manual inspections, as well as tools that allow senior engineers to develop inspection templates and profiles, reducing the requisite thermographic skill level of the operating engineer. Finally, the Sentence software can also offer complete independence of operator decisions by the fully automated "Beep on Defect" detection functionality. The end-to-end automatic inspection system includes sub-systems for defining a panel profile, generating an inspection plan, controlling a robot-arm and capturing thermographic images to detect defects. A statistical model has been built to analyze the entire image, evaluate grey-scale ranges, import sentencing criteria and automatically detect impact damage defects. A full width half maximum algorithm has been used to quantify the flaw sizes. The identified defects are imported into the sentencing engine which then sentences (automatically compares analysis results against acceptance criteria) the inspection by comparing the most significant defect or group of defects against the inspection standards.

  11. Testing and analysis of internal hardwood log defect prediction models

    Treesearch

    R. Edward Thomas

    2011-01-01

    The severity and location of internal defects determine the quality and value of lumber sawn from hardwood logs. Models have been developed to predict the size and position of internal defects based on external defect indicator measurements. These models were shown to predict approximately 80% of all internal knots based on external knot indicators. However, the size...

  12. Synergistic effects of dimethyloxallyl glycine and recombinant human bone morphogenetic protein-2 on repair of critical-sized bone defects in rats

    PubMed Central

    Qi, Xin; Liu, Yang; Ding, Zhen-yu; Cao, Jia-qing; Huang, Jing-huan; Zhang, Jie-yuan; Jia, Wei-tao; Wang, Jing; Liu, Chang-sheng; Li, Xiao-lin

    2017-01-01

    In bone remodeling, osteogenesis is closely coupled to angiogenesis. Bone tissue engineering using multifunctional bioactive materials is a promising technique which has the ability to simultaneously stimulate osteogenesis and angiogenesis for repair of bone defects. We developed mesoporous bioactive glass (MBG)-doped poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) composite scaffolds as delivery vehicle. Two bioactive molecules, dimethyloxalylglycine (DMOG), a small-molecule angiogenic drug, and recombinant human bone morphogenetic protein-2 (rhBMP-2), an osteoinductive growth factor, were co-incorporated into the scaffold. The synergistic effects of DMOG and rhBMP-2 released in the composite scaffolds on osteogenic and angiogenic differentiation of hBMSCs were investigated using real-time quantitative polymerase chain reaction and western blotting. Moreover, in vivo studies were conducted to observe bone regeneration and vascular formation of critical-sized bone defects in rats using micro-computed tomography, histological analyses, Microfil® perfusion, fluorescence labeling, and immunohistochemical analysis. The results showed that DMOG and rhBMP-2 released in the MBG-PHBHHx scaffolds did exert synergistic effects on the osteogenic and angiogenic differentiation of hBMSCs. Moreover, DMOG and rhBMP-2 produced significant increases in newly-formed bone and neovascularization of calvarial bone defects in rats. It is concluded that the co-delivery strategy of both rhBMP-2 and DMOG can significantly improve the critical-sized bone regeneration. PMID:28230059

  13. Synergistic effects of dimethyloxallyl glycine and recombinant human bone morphogenetic protein-2 on repair of critical-sized bone defects in rats

    NASA Astrophysics Data System (ADS)

    Qi, Xin; Liu, Yang; Ding, Zhen-Yu; Cao, Jia-Qing; Huang, Jing-Huan; Zhang, Jie-Yuan; Jia, Wei-Tao; Wang, Jing; Liu, Chang-Sheng; Li, Xiao-Lin

    2017-02-01

    In bone remodeling, osteogenesis is closely coupled to angiogenesis. Bone tissue engineering using multifunctional bioactive materials is a promising technique which has the ability to simultaneously stimulate osteogenesis and angiogenesis for repair of bone defects. We developed mesoporous bioactive glass (MBG)-doped poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) composite scaffolds as delivery vehicle. Two bioactive molecules, dimethyloxalylglycine (DMOG), a small-molecule angiogenic drug, and recombinant human bone morphogenetic protein-2 (rhBMP-2), an osteoinductive growth factor, were co-incorporated into the scaffold. The synergistic effects of DMOG and rhBMP-2 released in the composite scaffolds on osteogenic and angiogenic differentiation of hBMSCs were investigated using real-time quantitative polymerase chain reaction and western blotting. Moreover, in vivo studies were conducted to observe bone regeneration and vascular formation of critical-sized bone defects in rats using micro-computed tomography, histological analyses, Microfil® perfusion, fluorescence labeling, and immunohistochemical analysis. The results showed that DMOG and rhBMP-2 released in the MBG-PHBHHx scaffolds did exert synergistic effects on the osteogenic and angiogenic differentiation of hBMSCs. Moreover, DMOG and rhBMP-2 produced significant increases in newly-formed bone and neovascularization of calvarial bone defects in rats. It is concluded that the co-delivery strategy of both rhBMP-2 and DMOG can significantly improve the critical-sized bone regeneration.

  14. High-resolution axial MR imaging of tibial stress injuries

    PubMed Central

    2012-01-01

    Purpose To evaluate the relative involvement of tibial stress injuries using high-resolution axial MR imaging and the correlation with MR and radiographic images. Methods A total of 33 patients with exercise-induced tibial pain were evaluated. All patients underwent radiograph and high-resolution axial MR imaging. Radiographs were taken at initial presentation and 4 weeks later. High-resolution MR axial images were obtained using a microscopy surface coil with 60 × 60 mm field of view on a 1.5T MR unit. All images were evaluated for abnormal signals of the periosteum, cortex and bone marrow. Results Nineteen patients showed no periosteal reaction at initial and follow-up radiographs. MR imaging showed abnormal signals in the periosteal tissue and partially abnormal signals in the bone marrow. In 7 patients, periosteal reaction was not seen at initial radiograph, but was detected at follow-up radiograph. MR imaging showed abnormal signals in the periosteal tissue and entire bone marrow. Abnormal signals in the cortex were found in 6 patients. The remaining 7 showed periosteal reactions at initial radiograph. MR imaging showed abnormal signals in the periosteal tissue in 6 patients. Abnormal signals were seen in the partial and entire bone marrow in 4 and 3 patients, respectively. Conclusions Bone marrow abnormalities in high-resolution axial MR imaging were related to periosteal reactions at follow-up radiograph. Bone marrow abnormalities might predict later periosteal reactions, suggesting shin splints or stress fractures. High-resolution axial MR imaging is useful in early discrimination of tibial stress injuries. PMID:22574840

  15. Does a conservative tibial cut in conventional total knee arthroplasty violate the deep medial collateral ligament?

    PubMed

    Maes, Michael; Luyckx, Thomas; Bellemans, Johan

    2014-11-01

    Based on the anatomy of the deep medial collateral ligament (MCL), it was hypothesized that at least part of its cross-sectional insertion area is jeopardized while performing a standard tibial cut in conventional total knee arthroplasty (TKA). The aim of this study was to determine whether it is anatomically possible to preserve the tibial deep MCL insertion during conventional TKA. Thirty-three unpaired cadaveric knee specimens were used for this study. Knees with severe varus/valgus deformity or damage to the medial structures of the knee were excluded. In the first part of the study, the dimensions of the tibial insertion of the deep MCL and its relationship to the joint line were recorded. Next, the cross-sectional area of the deep MCL insertion was determined using calibrated digital photographic analysis. In the second part, the effect of a standard 9-mm 3° sloped tibial cut on the structural integrity of the deep MCL cross-sectional insertion area was determined using conventional instrumentation. The proximal border of the deep MCL insertion site on the tibia was located on average 4.7 ± 1.2 mm distally to the joint line. After performing a standard 9-mm 3° sloped tibial cut, on average 54% of the deep MCL insertion area was resected. In 29% of the cases, the deep MCL insertion area was completely excised. The deep MCL cannot routinely be preserved in conventional TKA. The deep MCL insertion is at risk and may be jeopardized in case of a tibial cut 9 mm below the native joint line. As the deep MCL is a distinct medial stabilizer and plays an important role in rotational stability, this may have implications in future designs of both unicondylar and total knee arthroplasty, but further research is necessary.

  16. Topological defects in extended inflation

    NASA Technical Reports Server (NTRS)

    Copeland, Edmund J.; Kolb, Edward W.; Liddle, Andrew R.

    1990-01-01

    The production of topological defects, especially cosmic strings, in extended inflation models was considered. In extended inflation, the Universe passes through a first-order phase transition via bubble percolation, which naturally allows defects to form at the end of inflation. The correlation length, which determines the number density of the defects, is related to the mean size of bubbles when they collide. This mechanism allows a natural combination of inflation and large scale structure via cosmic strings.

  17. Histologic Evaluation of Critical Size Defect Healing With Natural and Synthetic Bone Grafts in the Pigeon ( Columba livia ) Ulna.

    PubMed

    Tunio, Ahmed; Jalila, Abu; Goh, Yong Meng; Shameha-Intan; Shanthi, Ganabadi

    2015-06-01

    Fracture and bone segment loss are major clinical problems in birds. Achieving bone formation and clinical union in a fracture case is important for the survival of the bird. To evaluate the efficacy of bone grafts for defect healing in birds, 2 different bone grafts were investigated in the healing of a bone defect in 24 healthy pigeons ( Columba livia ). In each bird, a 1-cm critical size defect (CSD) was created in the left ulna, and the fracture was stabilized with external skeletal fixation (ESF). A graft of hydroxyapatite (HA) alone (n = 12 birds) or demineralized bone matrix (DBM) combined with HA (n = 12 birds) was implanted in the CSD. The CSD healing was evaluated at 3 endpoints: 3, 6, and 12 weeks after surgery. Four birds were euthanatized at each endpoint from each treatment group, and bone graft healing in the ulna CSD was evaluated by histologic examination. The CSD and graft implants were evaluated for quality of union, cortex development, and bone graft incorporation. Results showed no graft rejection in any bird, and all birds had connective tissue formation in the defect because of the bone graft application. These results suggest that bone defect healing can be achieved by a combination of osteoinductive and osteoconductive bone graft materials for clinical union and new bone regeneration in birds. The combination of DBM and HA resulted in a better quality bone graft (P < .05) than did HA alone, but there was no significant differences in cortex development or bone graft incorporation at 3, 6, or 12 weeks. From the results of this study, we conclude that HA bone grafts, alone or in combination with DBM, with external skeletal fixation is suitable and safe for bone defect and fracture treatment in pigeons.

  18. Strain measurements of the tibial insert of a knee prosthesis using a knee motion simulator.

    PubMed

    Sera, Toshihiro; Iwai, Yuya; Yamazaki, Takaharu; Tomita, Tetsuya; Yoshikawa, Hideki; Naito, Hisahi; Matsumoto, Takeshi; Tanaka, Masao

    2017-12-01

    The longevity of a knee prosthesis is influenced by the wear of the tibial insert due to its posture and movement. In this study, we assumed that the strain on the tibial insert is one of the main reasons for its wear and investigated the influence of the knee varus-valgus angles on the mechanical stress of the tibial insert. Knee prosthesis motion was simulated using a knee motion simulator based on a parallel-link six degrees-of-freedom actuator and the principal strain and pressure distribution of the tibial insert were measured. In particular, the early stance phase obtained from in vivo X-ray images was examined because the knee is applied to the largest load during extension/flexion movement. The knee varus-valgus angles were 0° (neutral alignment), 3°, and 5° malalignment. Under a neutral orientation, the pressure was higher at the middle and posterior condyles. The first and second principal strains were larger at the high and low pressure areas, respectively. Even for a 3° malalignment, the load was concentrated at one condyle and the positive first principal strain increased dramatically at the high pressure area. The negative second principal strain was large at the low pressure area on the other condyle. The maximum equivalent strain was 1.3-2.1 times larger at the high pressure area. For a 5° malalignment, the maximum equivalent strain increased slightly. These strain and pressure measurements can provide the mechanical stress of the tibial insert in detail for determining the longevity of an artificial knee joint.

  19. [Management of cerebrospinal fluid leaks according to size. Our experience].

    PubMed

    Alobid, Isam; Enseñat, Joaquim; Rioja, Elena; Enriquez, Karla; Viscovich, Liza; de Notaris, Matteo; Bernal-Sprekelsen, Manuel

    2014-01-01

    We present our experience in the reconstruction of cerebrospinal fluid (CSF) leaks according to their size and location. Fifty-four patients who underwent advanced skull base surgery (large defects) and 62 patients with CSF leaks of different origin (small and medium-sized defects) were included. Large defects were reconstructed with a nasoseptal pedicled flap positioned on fat and fascia lata and lumbar drainage was used. In small and medium-sized leaks of other origin, intrathecal fluorescein 5% was applied previously to identify the defect. Fascia lata in an underlay position was used for reconstruction, which was then covered with mucoperiosteum from the turbinate. Perioperative antibiotics were administered for 5-7 days. Nasal packing was removed after 24-48 hours. The most frequent aetiology for small and medium-sized defects was spontaneous (48.4%), followed by trauma (24.2%), iatrogenic (5%) and others. The success rate was of 91% after the first surgery and 98% in large skull base defects and small/medium-sized respectively. After rescue surgery, the rate of closure achieved was 100%. The follow-up was 15.6 ± 12.4 months for large defects and 75.3 ± 51.3 months for small/medium-sized defects without recurrence. Endoscopic surgery for closure of any type of skull base defect is the gold standard approach. Defect size does not play a significant role in the success rate. Fascia lata and mucoperiosteum allow a reconstruction of small/medium-sized defects. For larger skull base defects, a combination of fat, fascia lata and nasoseptal pedicled flaps provide a successful reconstruction. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  20. Management of Open Tibial Shaft Fractures: Does the Timing of Surgery Affect Outcomes?

    PubMed

    Duyos, Oscar A; Beaton-Comulada, David; Davila-Parrilla, Ariel; Perez-Lopez, Jose Carlos; Ortiz, Krystal; Foy-Parrilla, Christian; Lopez-Gonzalez, Francisco

    2017-03-01

    Open tibial shaft fractures require emergent care. Treatment with intravenous antibiotics and fracture débridement within 6 to 24 hours is recommended. Few studies have examined outcomes when surgical treatment is performed >24 hours after occurrence of the fracture. This retrospective study included 227 patients aged ≥18 years with isolated open tibial shaft fractures in whom the time to initial débridement was >24 hours. The statistical analysis was based on time from injury to surgical débridement, Gustilo-Anderson classification, method of fixation, union status, and infection status. Fractures débrided within 24 to 48 hours and 48 to 96 hours after injury did not show a statistically significant difference in terms of infection rates (P = 0.984). External fixation showed significantly greater infection rates (P = 0.044) and nonunion rates (P = 0.001) compared with intramedullary nailing. Open tibial shaft fractures should be débrided within 24 hours after injury. Our data indicate that after the 24-hour period and up to 4 days, the risk of infection remains relatively constant independent of the time to débridement. Patients treated with external fixation had more complications than did patients treated with other methods of fixation. Primary reamed intramedullary nailing appears to be a reasonable option for the management of Gustilo-Anderson types 1 and 2 open tibial shaft fractures. Level III retrospective study.

  1. Tibial lengthening using a humeral intramedullary nail combined with a single-plane external fixator for leg discrepancy in sequelae of poliomyelitis.

    PubMed

    Chen, Daoyun; Chen, Jianmin; Liu, Fanggang; Jiang, Yao

    2011-03-01

    The sequelae of poliomyelitis are the common causes of leg discrepancy. Tibial lengthening is an effective way to solve this problem but it is associated with a high rate of complications. In this study, we combined the use of humeral nail and external fixator in tibial lengthening with the purpose of reducing lengthening complications. Compared with the cases lengthened by a single-plane external fixator alone, this combined strategy was found to be beneficial in maintaining the tibial alignment. Therefore, it can be recommended as a good technique for tibial lengthening in patients with sequelae of poliomyelitis.

  2. Application of Hydrogel in Reconstruction Surgery: Hydrogel/Fat Graft Complex Filler for Volume Reconstruction in Critical Sized Muscle Defects.

    PubMed

    Lui, Y F; Ip, W Y

    2016-01-01

    Autogenic fat graft usually suffers from degeneration and volume shrinkage in volume reconstruction applications. How to maintain graft viability and graft volume is an essential consideration in reconstruction therapies. In this presented investigation, a new fat graft transplantation method was developed aiming to improve long term graft viability and volume reconstruction effect by incorporation of hydrogel. The harvested fat graft is dissociated into small fragments and incorporated into a collagen based hydrogel to form a hydrogel/fat graft complex for volume reconstruction purpose. In vitro results indicate that the collagen based hydrogel can significantly improve the survivability of cells inside isolated graft. In a 6-month investigation on artificial created defect model, this hydrogel/fat graft complex filler has demonstrated the ability of promoting fat pad formation inside the targeted defect area. The newly generated fat pad can cover the whole defect and restore its original dimension in 6-month time point. Compared to simple fat transplantation, this hydrogel/fat graft complex system provides much improvement on long term volume restoration effect against degeneration and volume shrinkage. One notable effect is that there is continuous proliferation of adipose tissue throughout the 6-month period. In summary, the hydrogel/fat graft system presented in this investigation demonstrated a better and more significant effect on volume reconstruction in large sized volume defect than simple fat transplantation.

  3. A Biomechanical Study of Posteromedial Tibial Plateau Fracture Stability: Do They All Require Fixation?

    PubMed

    Cuéllar, Vanessa G; Martinez, Danny; Immerman, Igor; Oh, Cheongeun; Walker, Peter S; Egol, Kenneth A

    2015-07-01

    Although the posteromedial fragment in tibial plateau fractures is often considered unstable, biomechanical evidence supporting this view is lacking. We aimed to evaluate the stability of the fragment in a cadaver model. Our hypothesis was that under the expected small axial force during rehabilitation and the combined effects of this force with shear force, internal rotation torque, and varus moment, the most common posteromedial tibial fragment morphology could maintain stability in early flexion. Axial compression force alone or combined with posterior shear, internal rotation torque, or varus moment was applied to the femurs of 5 fresh cadaveric knees. A Tekscan pressure mapping system was used to measure pressure and contact area between the femoral condyles, meniscus, and tibial plateau. A Microscribe 3D digitizer was used to define the 3-dimensional positions of the femur and tibia. A 10-mm and then a 20-mm osteotomy was created with a saw at an angle of 30 degrees in the axial plane with respect to the tangent of the posterior tibial plateau and 75 degrees in the sagittal plane, representing a typical posteromedial fracture fragment. At each flexion angle (15, 30, 60, 90, and 120 degrees) and loading condition (axial compression only, compression with shear force, torque, and varus moment), distal displacement of the medial femoral condyle and the tibial fracture fragments was determined. For the 10-mm fragment, medial femoral condyle displacement was little affected up to approximately 30-degree flexion, after which it increased. For the 20-mm fragment, there was progressive medial femoral condyle displacement with increasing flexion from baseline. However, for the 10- and 20-mm fragments themselves, displacements were noted at every flexion angle, starting at 1.7 mm inferior displacement with 15 degrees of flexion and internal rotation torque and up to 10.2 mm displacement with 90 degrees of flexion and varus bending moment. In this cadaveric model of a

  4. Negative Pressure Wound Therapy (NPWT) to Treat Complex Defect of the Leg after Electrical Burn.

    PubMed

    Tevanov, Iulia; Enescu, Dan M; Bălănescu, Radu; Sterian, G; Ulici, Alexandru

    2016-01-01

    Negative pressure wound therapy is a non-invasive treatment that uses under atmospheric pressure to increase blood supply to the wound, stimulating the formation of granulation tissue, angiogenesis, proliferation of fibroblasts and endothelial cells. Negative pressure therapy has also the ability to decrease the bacterial load, reduce swelling and decrease exudate while maintaining a moist environment that facilitates healing. Our patient, a 17 year old male, suffered major third and fourth-degree high voltage electrical burns on 60% of the body surface, in November 2011. After the excision of the necrotic tissue (muscles and tendons), the lower extremity of the right leg- the tibial bone, the fibula, external and internal malleoli became exposed circularly. The soft-tissue defect was partially covered by using an internal twin muscle flap and free split skin. Then, a cross leg flap technique has been used, partially covering the defect with a contralateral thigh flap. Surface swab cultures were positive for Pseudomonas aeruginosa. In October 2013 the patient was transferred to our department. The clinical examination of the right leg showed that the tibial bone had been exposed on an area of 15/3 cm in the lower half. The peroneal malleolus had also been exposed. The resection of the devitalized, exposed tibia and the avivement of the wound edges were performed. Then the NPWT was started and performed by intermittent suction. Local cleansing, soft-tissue avivement and dressing changes were performed twice a week for 6 weeks. After six weeks of NPWT and eleven dressing changes under general anaesthesia, the wounds were ready for skin grafting. Granulation tissue was formed, covering the entire surface of both the tibia bone and the peroneal malleolus. Both receptor beds were covered with free skin graft harvested from the ipsilateral thigh. The mechanical suture of the skin grafts was performed and the grafts were covered with damp dressing. By using the NPWT it

  5. Effects of nandrolone decanoate on time to consolidation of bone defects resulting from osteotomy for tibial tuberosity advancement.

    PubMed

    Marques, Danilo R C; Marques, Danilo; Ibanez, Jose F; Freitas, Itallo B; Hespanha, Ana C; Monteiro, Juliana F; Eggert, Mayara; Becker, Amanda

    2017-09-12

    Experimental study. The aim of this study was to evaluate the effect of nandrolone decanoate (ND) on the time taken for bone consolidation in dogs undergoing tibial tuberosity advancement surgery (TTA). Seventeen dogs that underwent TTA surgery were randomly divided into two groups: group C (TTA; 9 stifles), and group TTA+ND (TTA and systemic administration of ND; 8 stifles). Three observers (two radiologists and an orthopaedic surgeon), assessed bone consolidation by visual inspection of serial radiographs at intervals of 21 days following surgery. There were no differences in median weight and age between groups, nor between the medians of the variables right and left stifle. Only weight and age values were normally distributed. The other variables, right and left stifle and time to consolidation, showed non-normal distribution. Meniscal injury was present in all animals in group C and all animals in group TTA+ND. There was a significant difference between time to consolidation in groups C and TTA+ND (p <0.05). One animal in the group TTA+ND showed increased libido. Kappa agreement among observers on radiographs was 0.87. Administration of ND reduces time to bone consolidation in dogs undergoing TTA.

  6. [CLINICAL APPLICATION AND EXPERIENCE IN RECONSTRUCTION OF SOFT TISSUE DEFECTS FOLLOWING MALIGNANT TUMOR REMOVAL OF LIMBS USING PERFORATOR PROPELLER FLAPS].

    PubMed

    Zhu, Shan; Liu, Yuanbo; Yu, Shengji; Zang, Mengqing; Zhao, Zhenguo; Xu, Libin; Zhang, Xinxin; Chen, Bo; Ding, Qiang

    2016-01-01

    To explore the feasibility and technical essentials of soft tissue defect reconstruction following malignant tumor removal of limbs using perforator propeller flaps. Between July 2008 and July 2015, 19 patients with malignant limb tumor underwent defect reconstruction following tumor removal using the perforator propeller flaps. There were 13 males and 6 females with an average age of 53.4 years (range, 20-82 years). The disease duration ranged from 1 to 420 months (mean, 82 months). The tumors located at the thigh in 10 cases, at the leg in 2 cases, at the arm in 1 case, at the forearm in 1 case, around the knee in 2 cases, and around the elbow joint in 3 cases. Totally 23 flaps (from 8 cm x 3 cm to 30 cm x 13 cm in size) were used to reconstruct defects (from 4 cm x 4 cm to 24 cm x 16 cm in size). The potential source arteries included the femoral artery (n = 2), profunda femoral artery (n = 3), superficial circumflex iliac artery (n = 1), lateral circumflex femoral artery (n = 6), superior lateral genicular artery (n = 2), peroneal artery (n = 2), anterior tibial artery (n = 1), brachial artery (n = 4), and radial artery (n = 1). The remaining one was a free style perforator flap. Partial distal flap necrosis occurred in 3 cases after surgery with rotation angles of 180, 150, and 100 degrees respectively, which were reconstructed after debridement using a free-style perforator flap in 1 case and using free skin grafting in the other 2 cases. The other 20 flaps survived completely after surgery. Primary healing of incisions was obtained at the donor and recipient sites. There was no severe complication such as infection, hematoma, and total flap failure. All patients were followed up 3 months to 5 years (mean, 19 months). One patient with malignant melanoma around the elbow joint had tumor recurrence, and underwent secondary tumor resection. The appearance, texture, and color of the flaps were similar to those at the recipient site. For patients with malignant

  7. Effects of tibial slope changes in the stability of fixed bearing medial unicompartmental arthroplasty in anterior cruciate ligament deficient knees.

    PubMed

    Suero, Eduardo M; Citak, Musa; Cross, Michael B; Bosscher, Marianne R F; Ranawat, Anil S; Pearle, Andrew D

    2012-08-01

    Patients with anterior cruciate ligament (ACL) deficiency may have increased failure rates with UKA as a result of abnormal contact stresses and altered knee kinematics. Variations in the slope of the tibial component in UKA may alter tibiofemoral translation, and affect outcomes. This cadaveric study evaluated tibiofemoral translation during the Lachman and pivot shift tests after changing the slope of a fixed bearing unicondylar tibial component. Sectioning the ACL increased tibiofemoral translation in both the Lachman and pivot shift tests (P<0.05). Tibial slope leveling (decreasing the posterior slope) of the polyethylene insert in a UKA decreases anteroposterior tibiofemoral translation in the sagittal plane to a magnitude similar to that of the intact knee. With 8° of tibial slope leveling, anterior tibial translation during the Lachman test decreased by approximately 5mm. However, no variation in slope altered the pivot shift kinematics in the ACL deficient knees. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Guided bone regeneration produced by new mineralized and reticulated collagen membranes in critical-sized rat calvarial defects

    PubMed Central

    Leitão, Renata FC; Figueiró, Sônia D; Góes, Júlio C; Lima, Vilma; Silveira, Charles O; Brito, Gerly AC

    2015-01-01

    The aim of this study was to evaluate the bone regenerative effect of glutaraldehyde (GA) cross-linking on mineralized polyanionic collagen membranes in critical-sized defects on rat calvarias. Bone calvarial defects were induced in Wistar rats, which were then divided into five groups: a sham group; a control group, which received a commercial membrane; and GA, 25GA, and 75GA groups, which received one of three different polyanionic collagen membranes mineralized by 0, 25, or 75 hydroxyapatite cycles and then cross-linked by GA. Bone formation was evaluated based on digital radiography and computerized tomography. Histological analyses were performed 4 and 12 weeks after the surgical procedure to observe bone formation, membrane resorption, and fibrous tissue surrounding the membranes. Measurement of myeloperoxidase activity, tumor necrosis factor alpha, and interleukin 1beta production was performed 24 h after surgery. The percentage of new bone formation in the GA, 25GA, and 75GA groups was higher compared with the control and sham groups. In the GA and 25 GA groups, the membranes were still in place and were contained in a thick fibrous capsule after 12 weeks. No significant difference was found among the groups regarding myeloperoxidase activity and interleukin 1beta levels, although the GA, 25GA, and 75GA groups presented decreased levels of tumor necrosis factor alpha compared with the control group. These new GA cross-linked membranes accelerated bone healing of the calvarium defects and did not induce inflammation. In addition, unlike the control membrane, the experimental membranes were not absorbed during the analyzed period, so they may offer advantages in large bone defects where prolonged membrane barrier functions are desirable. PMID:25245073

  9. Production of UT Reference Blocks Containing Artificially Introduced Defects

    NASA Astrophysics Data System (ADS)

    Kaya, A. A.; Ucuncuoglu, S.; Kurkcu, N.; Kandemir, A.; Arslan, H.

    2007-03-01

    Metallic blocks of Inconel 718 and Ti-6A1-4V alloys that contain artificially introduced defects of known type, size, shape and location were prepared to serve as calibration standards in ultrasonic inspection. The synthetic defects employed to serve as reflectors were all pertinent to the specific alloy systems used, i.e. compositional defects termed as `dirty white' `white spot' and `freckle' for Inconel 718; `hard-alpha' for titanium alloy. Furthermore, as a defect type common to all three materials, spherical voids of various sizes were also incorporated into these calibration blocks. The aim of this study is to introduce defects of known type and size into metallic blocks made of superalloy Inconel 718 and titanium Ti-6A1-4V alloy. The scope of the study entailed determination of the correct parameters for manufacturing processes involved. Based on the results of the preceding phases of this study, it was decided that the method of Vacuum Hot Pressing (VHP) was to be used in this project to manufacture the metallic block containing artificial defects.

  10. Radiologic assessment of femoral and tibial tunnel placement based on anatomic landmarks in arthroscopic single bundle anterior cruciate ligament reconstruction

    PubMed Central

    Nema, Sandeep Kumar; Balaji, Gopisankar; Akkilagunta, Sujiv; Menon, Jagdish; Poduval, Murali; Patro, Dilip

    2017-01-01

    Background: Accurate tibial and femoral tunnel placement has a significant effect on outcomes after anterior cruciate ligament reconstruction (ACLR). Postoperative radiographs provide a reliable and valid way for the assessment of anatomical tunnel placement after ACLR. The aim of this study was to examine the radiographic location of tibial and femoral tunnels in patients who underwent arthroscopic ACLR using anatomic landmarks. Patients who underwent arthroscopic ACLR from January 2014 to March 2016 were included in this retrospective cohort study. Materials and Methods: 45 patients who underwent arthroscopic ACLR, postoperative radiographs were studied. Femoral and tibial tunnel positions on sagittal and coronal radiographic views, graft impingement, and femoral roof angle were measured. Radiological parameters were summarized as mean ± standard deviation and proportions as applicable. Interobserver agreement was measured using intraclass correlation coefficient. Results: The position of the tibial tunnel was found to be at an average of 35.1% ± 7.4% posterior from the anterior edge of the tibia. The femoral tunnel was found at an average of 30% ± 1% anterior to the posterior femoral cortex along the Blumensaat's line. Radiographic impingement was found in 34% of the patients. The roof angle averaged 34.3° ± 4.3°. The position of the tibial tunnel was found at an average of 44.16% ± 3.98% from the medial edge of the tibial plateau. The coronal tibial tunnel angle averaged 67.5° ± 8.9°. The coronal angle of the femoral tunnel averaged 41.9° ± 8.5°. Conclusions: The femoral and tibial tunnel placements correlated well with anatomic landmarks except for radiographic impingement which was present in 34% of the patients. PMID:28566780

  11. The effect of proximal tibial slope on dynamic stability testing of the posterior cruciate ligament- and posterolateral corner-deficient knee.

    PubMed

    Petrigliano, Frank A; Suero, Eduardo M; Voos, James E; Pearle, Andrew D; Allen, Answorth A

    2012-06-01

    Proximal tibial slope has been shown to influence anteroposterior translation and tibial resting point in the posterior cruciate ligament (PCL)-deficient knee. The effect of proximal tibial slope on rotational stability of the knee is unknown. Change in proximal tibial slope produced via osteotomy can influence both static translation and dynamic rotational kinematics in the PCL/posterolateral corner (PLC)-deficient knee. Controlled laboratory study. Posterior drawer, dial, and mechanized reverse pivot-shift (RPS) tests were performed on hip-to-toe specimens and translation of the lateral and medial compartments measured utilizing navigation (n = 10). The PCL and structures of the PLC were then sectioned. Stability testing was repeated, and compartmental translation was recorded. A proximal tibial osteotomy in the sagittal plane was then performed achieving either +5° or -5° of tibial slope variation, after which stability testing was repeated (n = 10). Analysis was performed using 1-way analysis of variance (ANOVA; α = .05). Combined sectioning of the PCL and PLC structures resulted in a 10.5-mm increase in the posterior drawer, 15.5-mm increase in the dial test at 30°, 14.5-mm increase in the dial test at 90°, and 17.9-mm increase in the RPS (vs intact; P < .05). Increasing the posterior slope (high tibial osteotomy [HTO] +5°) in the PCL/PLC-deficient knee reduced medial compartment translation by 3.3 mm during posterior drawer (vs deficient; P < .05) but had no significant effect on the dial test at 30°, dial test at 90°, or RPS. Conversely, reversing the slope (HTO -5°) caused a 4.8-mm increase in medial compartment translation (vs deficient state; P < .05) during posterior drawer and an 8.6-mm increase in lateral compartment translation and 9.0-mm increase in medial compartment translation during RPS (vs deficient state; P < .05). Increasing posterior tibial slope diminished static posterior instability of the PCL/PLC-deficient knee as measured by the

  12. Rehabilitation after cell transplantation for cartilage defects.

    PubMed

    Deszczynski, J; Slynarski, K

    2006-01-01

    Rehabilitation is a key element of successful treatment of cartilage defects with cell transplantation. The process of graft maturation takes approximately 18 months and cannot be accelerated, but requires carefully introduced steps leading to early recovery of joint function. Rehabilitation starts at 8 hours after surgery with the continuous passive motion (CPM) exercises and physiotherapy. For the first 6 weeks, patients continue with CPM in the range of 0 degrees to 45 degrees for femoral and tibial defects and 0 degrees to 30 degrees for patellofemoral joint reconstruction. Isometric muscle training and scar manual therapy are introduced. Patients are allowed to weight-bear as tolerated from the second week after surgery. After this initial phase, from 6 to 8 weeks after surgery, rehabilitation is accelerated with increased load-bearing and progressive range of motion to full flexion. Usually patients are able to walk without crutches in this time. Proprioceptive training is introduced with the advance of pain-free full range of motion and no discomfort with full weight-bearing. At 6 months after surgery, most patients recover joint function, making it possible for them to return to daily living activities. However, they need to continue with muscle, proprioceptive, and sports-specific rehabilitation exercises. The rehabilitation process is complicated, requiring close cooperation between the patient and surgeon-physiotherapist team to understand the symptoms and address them in a timely fashion.

  13. Uncemented three-dimensional-printed prosthetic reconstruction for massive bone defects of the proximal tibia.

    PubMed

    Lu, Minxun; Li, Yongjiang; Luo, Yi; Zhang, Wenli; Zhou, Yong; Tu, Chongqi

    2018-03-06

    Currently, it is challenging to treat massive bone defects of proximal tibia. Although numerous methods are available for reconstruction with epiphysis preservation, limitations in knee function and complications are noted with these methods. Our paper describes our attempt to reconstruct a marked defect in the proximal tibia with an uncemented three-dimensional (3D)-printed prosthesis and to evaluate the prosthesis design and short-term outcomes. A 15-year-old boy with metaphyseal osteosarcoma of the tibia underwent intercalary allograft reconstruction following wide tumour resection with epiphysis preservation. However, chronic allograft rejection and/or infection occurred after the surgery and a sinus tract was formed. The rejection and/or infection process was successfully stopped by the removal of the graft and implantation of an antibiotic-loaded cement spacer; however, the limb function was poor. Because of the irregular shape of the defect and the excessively short length of the residual proximal tibia, we used the 3D printing technology to design and fabricate a personalised prosthesis to reconstruct the defect, with the preservation of the knee joint. At the last follow-up at 26 months, the patient had satisfactory limb function. The 3D-printed prosthesis may be a feasible option in the reconstruction of tibial metaphyseal defects with the preservation of the knee joint. Moreover, it can result in good postoperative function and low complication rates. However, a long-term follow-up is required to clarify its long-term outcomes.

  14. Mixed nano/micro-sized calcium phosphate composite and EDTA root surface etching improve availability of graft material in intrabony defects: an in vivo scanning electron microscopy evaluation.

    PubMed

    Gamal, Ahmed Y; Iacono, Vincent J

    2013-12-01

    The use of nanoparticles of graft materials may lead to breakthrough applications for periodontal regeneration. However, due to their small particle size, nanoparticles may be eliminated from periodontal defects by phagocytosis. In an attempt to improve nanoparticle retention in periodontal defects, the present in vivo study uses scanning electron microscopy (SEM) to evaluate the potential of micrograft particles of β-tricalcium phosphate (β-TCP) to enhance the binding and retention of nanoparticles of hydroxyapatite (nHA) on EDTA-treated and non-treated root surfaces in periodontal defects after 14 days of healing. Sixty patients having at least two hopeless periodontally affected teeth designated for extraction were randomly divided into four treatment groups (15 patients per group). Patients in group 1 had selected periodontal intrabony defects grafted with nHA of particle size 10 to 100 nm. Patients in group 2 were treated in a similar manner but had the affected roots etched for 2 minutes with a neutral 24% EDTA gel before grafting of the associated vertical defects with nHA. Patients in group 3 had the selected intrabony defects grafted with a composite graft consisting of equal volumes of nHA and β-TCP (particle size 63 to 150 nm). Patients in group 4 were treated as in group 3 but the affected roots were etched with neutral 24% EDTA as in group 2. For each of the four groups, one tooth was extracted immediately, and the second tooth was extracted after 14 days of healing for SEM evaluation. Fourteen days after surgery, all group 1 samples were devoid of any nanoparticles adherent to the root surfaces. Group 2 showed root surface areas 44.7% covered by a single layer of clot-blended grafted particles 14 days following graft application. After 14 days, group 3 samples appeared to retain fibrin strands devoid of grafted particles. Immediately extracted root samples of group 4 had adherent graft particles that covered a considerable area of the root surfaces

  15. Locking plate fixation in distal metaphyseal tibial fractures: series of 79 patients.

    PubMed

    Gupta, Rakesh K; Rohilla, Rajesh Kumar; Sangwan, Kapil; Singh, Vijendra; Walia, Saurav

    2010-12-01

    Open reduction and internal fixation in distal tibial fractures jeopardises fracture fragment vascularity and often results in soft tissue complications. Minimally invasive osteosynthesis, if possible, offers the best possible option as it permits adequate fixation in a biological manner. Seventy-nine consecutive adult patients with distal tibial fractures, including one patient with a bilateral fracture of the distal tibia, treated with locking plates, were retrospectively reviewed. The 4.5-mm limited-contact locking compression plate (LC-LCP) was used in 33 fractures, the metaphyseal LCP in 27 fractures and the distal medial tibial LCP in the remaining 20 fractures. Fibula fixation was performed in the majority of comminuted fractures (n = 41) to maintain the second column of the ankle so as to achieve indirect reduction and to prevent collapse of the fracture. There were two cases of delayed wound breakdown in fractures fixed with the 4.5-mm LC-LCP. Five patients required primary bone grafting and three patients required secondary bone grafting. All cases of delayed union (n = 7) and nonunion (n = 3) were observed in cases where plates were used in bridge mode. Minimally invasive plate osteosynthesis (MIPO) with LCP was observed to be a reliable method of stabilisation for these fractures. Peri-operative docking of fracture ends may be a good option in severely impacted fractures with gap. The precontoured distal medial tibial LCP was observed to be a better tolerated implant in comparison to the 4.5-mm LC-LCP or metaphyseal LCP with respect to complications of soft tissues, bone healing and functional outcome, though its contour needs to be modified.

  16. Open-wedge high tibial osteotomy: comparison between manual and computer-assisted techniques.

    PubMed

    Iorio, R; Pagnottelli, M; Vadalà, A; Giannetti, S; Di Sette, P; Papandrea, P; Conteduca, F; Ferretti, A

    2013-01-01

    The purpose of our study was to compare clinical and radiological results of two groups of patients treated for medial compartment osteoarthritis of the knee with either conventional or computer-assisted open-wedge high tibial osteotomy (HTO). Goals of surgical treatment were a correction of the mechanical axis between 2° and 6° of valgus and a modification of posterior tibial slope between -2° and +2°. Twenty-four patients (27 knees) affected by varus knee deformity and operated with HTO were prospectively followed-up. They were randomly divided in two groups, A (11 patients, conventional treatment) and B (13 patients, navigated treatment). The American Knee Society Score and the Modified Cincinnati Rating System Questionnaire were used for clinical assessment. All patients were radiologically evaluated with a comparative lower limb weight-bearing digital radiograph, a standard digital anteroposterior, a latero-lateral radiograph of the knee, and a Rosenberg view. Patients were followed-up at a mean of 39 months. Clinical evaluation showed no statistical difference (n.s.) between the two groups. Radiological results showed an 86% reproducibility in achieving a mechanical axis of 182°-186° in group B compared to a 23% in group A (p = 0.0392); furthermore, in group B, we achieved a modification of posterior tibial slope between -2° and +2° in 100% of patients, while in group A, this goal was achieved only in 24% of cases (p = 0.0021). High tibial osteotomy with navigator is more accurate and reproducible in the correction of the deformity compared to standard technique. Therapeutic study, Level II.

  17. Fixator-assisted medial tibial plateau elevation to treat severe Blount's disease: outcomes at maturity.

    PubMed

    Fitoussi, F; Ilharreborde, B; Lefevre, Y; Souchet, P; Presedo, A; Mazda, K; Penneçot, G F

    2011-04-01

    Severe forms of Blount's disease may be associated with medial tibial plateau (MTP) depression. Management should then take account of joint congruence, laxity, limb axis, torsional abnomality, leg length discrepancy (LLD) and eventual recurrence history. Eight knees (six patients) were managed in a single step comprising MTP elevation osteotomy, lateral epiphysiodesis and proximal tibia osteotomy to correct varus and rotational deformity. Fixation was achieved using an Ilizarov external fixator. Mean age was 10.5 years. Mean hip-knee-ankle (HKA) angle was 151°; distal femoral varus, 94°; metaphyseal-diaphyseal angle (MDA), 27°; and angle of depression of the medial tibial plateau (ADMTP), 42°. Predicted residual proximal tibial growth was 2.6 cm. At a mean 48 months' follow-up, results were good in six cases, medium in one and poor (due to incomplete lateral epiphysiodesis) in one. Mean lateral tibial torsion was 9° and final LLD 11 mm. Weight-bearing was resumed at 2 months, and the fixator was removed at 5.5 months postoperatively. At end of follow-up, mean HKA angle was 179.6°, MDA 7.3° and ADMTP 5.4°. This technically demanding procedure gave satisfactory results in terms of axes and congruence; longer term assessment remains needed. Level IV. Retrospective study. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  18. Novel Osteoinductive Photo-cross-linkable Chitosan-lactide-fibrinogen Hydrogels Enhance Bone Regeneration in Critical Size Segmental Bone Defects

    DTIC Science & Technology

    2014-08-01

    an absorbable collagen sponge (ACS) is the FDA-approved device for clinical applications including lumbar spine fusion, open tibial fractures, and...fibrinogen on the morphological change of the CL hydrogels was observed. The hydrogel samples were incubated into PBS (pH 7.4) at 37°C for 1 day and... morphology was observed qualitatively using a Zeiss Axiovert 200 microscope (Carl Zeiss Microimaging, Thornwood, NY). Photomicrographs of cells

  19. Impact of facial defect reconstruction on attractiveness and negative facial perception.

    PubMed

    Dey, Jacob K; Ishii, Masaru; Boahene, Kofi D O; Byrne, Patrick; Ishii, Lisa E

    2015-06-01

    Measure the impact of facial defect reconstruction on observer-graded attractiveness and negative facial perception. Prospective, randomized, controlled experiment. One hundred twenty casual observers viewed images of faces with defects of varying sizes and locations before and after reconstruction as well as normal comparison faces. Observers rated attractiveness, defect severity, and how disfiguring, bothersome, and important to repair they considered each face. Facial defects decreased attractiveness -2.26 (95% confidence interval [CI]: -2.45, -2.08) on a 10-point scale. Mixed effects linear regression showed this attractiveness penalty varied with defect size and location, with large and central defects generating the greatest penalty. Reconstructive surgery increased attractiveness 1.33 (95% CI: 1.18, 1.47), an improvement dependent upon size and location, restoring some defect categories to near normal ranges of attractiveness. Iterated principal factor analysis indicated the disfiguring, important to repair, bothersome, and severity variables were highly correlated and measured a common domain; thus, they were combined to create the disfigured, important to repair, bothersome, severity (DIBS) factor score, representing negative facial perception. The DIBS regression showed defect faces have a 1.5 standard deviation increase in negative perception (DIBS: 1.69, 95% CI: 1.61, 1.77) compared to normal faces, which decreased by a similar magnitude after surgery (DIBS: -1.44, 95% CI: -1.49, -1.38). These findings varied with defect size and location. Surgical reconstruction of facial defects increased attractiveness and decreased negative social facial perception, an impact that varied with defect size and location. These new social perception data add to the evidence base demonstrating the value of high-quality reconstructive surgery. NA. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  20. Surgical treatment of a proximal diaphyseal tibial deformity associated with partial caudal and cranial cruciate ligament deficiency and patella baja.

    PubMed

    Vincenti, S; Knell, S; Pozzi, A

    2017-04-01

    Caudal cruciate ligament injury can be a complication following tibial plateau leveling osteotomy (TPLO) (Slocum und Slocum, 1993) especially if the post-operative Tibial Plateau Angle (TPA) is less than 5 degree. We describe a case of negative TPA associated with partial cranial and caudal ligament rupture treated with a center of rotation of angulation (CORA) based cranial tibial opening wedge osteotomy and tibial tuberosity transposition. A 13 kg, mixed breed dog was presented for right pelvic limb lameness. Radiographically a bilateral patella baja and a malformed tibia tuberosity along with a bilateral TPA of -8 degree were detected. Arthroscopically a partial rupture of the cranial and caudal cruciate ligaments were found. A cranial tibial opening wedge osteotomy of 23 degree and a fibular ostectomy were performed. The osteotomy was fixed with a 8 holes ALPS 9 (KYON, Switzerland) and a 3-holes 2.0mm UniLock plate (Synthes, Switzerland). Then a proximal tibial tuberosity transposition of 10mm was performed and fixed with a pin and tension band construct. The postoperative TPA was 15 degree. The radiographic controls at 6, 10 weeks, 6 months and 1 year after surgery revealed an unchanged position of the implants and progressive healing of the osteotomies. At the 6 and 12 months recheck evaluation the dog had no evidence of lameness or stifle pain and radiographs revealed complete healing of the osteotomy site and no implant failure. The diaphyseal CORA based osteotomy allowed accurate correction of a proximal tibial deformity associated with negative TPA.

  1. Lateralization of the Tibial Tubercle in Recurrent Patellar Dislocation: Verification Using Multiple Methods to Evaluate the Tibial Tubercle.

    PubMed

    Tensho, Keiji; Shimodaira, Hiroki; Akaoka, Yusuke; Koyama, Suguru; Hatanaka, Daisuke; Ikegami, Shota; Kato, Hiroyuki; Saito, Naoto

    2018-05-02

    The tibial tubercle deviation associated with recurrent patellar dislocation (RPD) has not been studied sufficiently. New methods of evaluation were used to verify the extent of tubercle deviation in a group with patellar dislocation compared with that in a control group, the frequency of patients who demonstrated a cutoff value indicating that tubercle transfer was warranted on the basis of the control group distribution, and the validity of these methods of evaluation for diagnosing RPD. Sixty-six patients with a history of patellar dislocation (single in 19 [SPD group] and recurrent in 47 [RPD group]) and 66 age and sex-matched controls were analyzed with the use of computed tomography (CT). The tibial tubercle-posterior cruciate ligament (TT-PCL) distance, TT-PCL ratio, and tibial tubercle lateralization (TTL) in the SPD and RPD groups were compared with those in the control group. Cutoff values to warrant 10 mm of transfer were based on either the minimum or -2SD (2 standard deviations below the mean) value in the control group, and the prevalences of patients in the RPD group with measurements above these cutoff values were calculated. The area under the curve (AUC) in receiver operating characteristic (ROC) curve analysis was used to assess the effectiveness of the measurements as predictors of RPD. The mean TT-PCL distance, TT-PCL ratio, and TTL were all significantly greater in the RPD group than in the control group. The numbers of patients in the RPD group who satisfied the cutoff criteria when they were based on the minimum TT-PCL distance, TT-PCL ratio, and TTL in the control group were 11 (23%), 7 (15%), and 6 (13%), respectively. When the cutoff values were based on the -2SD values in the control group, the numbers of patients were 8 (17%), 6 (13%), and 0, respectively. The AUC of the ROC curve for TT-PCL distance, TT-PCL ratio, and TTL was 0.66, 0.72, and 0.72, respectively. The extent of TTL in the RPD group was not substantial, and the percentages

  2. Biomechanical analysis of four different fixations for the posterolateral shearing tibial plateau fracture.

    PubMed

    Zhang, Wei; Luo, Cong-Feng; Putnis, Sven; Sun, Hui; Zeng, Zhi-Min; Zeng, Bing-Fang

    2012-03-01

    The posterolateral shearing tibial plateau fracture is uncommon in the literature, however with the increased usage of computer tomography (CT), the incidence of these fractures is no longer as low as previously thought. Few studies have concentrated on this fracture, least of all using a biomechanical model. The purpose of this study was to compare and analyse the biomechanical characteristics of four different types of internal fixation to stabilise the posterolateral shearing tibial plateau fracture. Forty synthetic tibiae (Synbone, right) simulated the posterolateral shearing fracture models and these were randomly assigned into four groups; Group A was fixed with two anterolateral lag screws, Group B with an anteromedial Limited Contact Dynamic Compression Plate (LC-DCP), Group C with a lateral locking plate, and Group D with a posterolateral buttress plate. Vertical displacement of the posterolateral fragment was measured using three different strengths of axial loading force, and finally loaded until fixation failure. It was concluded that the posterolateral buttress plate is biomechanically the strongest fixation method for the posterolateral shearing tibial plateau fracture. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Improvement of the knee center of rotation during walking after opening wedge high tibial osteotomy.

    PubMed

    Kim, Kyungsoo; Feng, Jun; Nha, Kyung Wook; Park, Won Man; Kim, Yoon Hyuk

    2015-06-01

    Accurate measurement of the center of rotation of the knee joint is indispensable for prediction of joint kinematics and kinetics in musculoskeletal models. However, no study has yet identified the knee center of rotations during several daily activities before and after high tibial osteotomy surgery, which is one surgical option for treating knee osteoarthritis. In this study, an estimation method for determining the knee joint center of rotation was developed by applying the optimal common shape technique and symmetrical axis of rotation approach techniques to motion-capture data and validated for typical activities (walking, squatting, climbing up stairs, walking down stairs) of 10 normal subjects. The locations of knee joint center of rotations for injured and contralateral knees of eight subjects with osteoarthritis, both before and after high tibial osteotomy surgery, were then calculated during walking. It was shown that high tibial osteotomy surgery improved the knee joint center of rotation since the center of rotations for the injured knee after high tibial osteotomy surgery were significantly closer to those of the normal healthy population. The difference between the injured and contralateral knees was also generally reduced after surgery, demonstrating increased symmetry. These results indicate that symmetry in both knees can be recovered in many cases after high tibial osteotomy surgery. Moreover, the recovery of center of rotation in the injured knee was prior to that of symmetry. This study has the potential to provide fundamental information that can be applied to understand abnormal kinematics in patients, diagnose knee joint disease, and design a novel implants for knee joint surgeries. © IMechE 2015.

  4. Arthroscopic evaluation of soft tissue injuries in tibial plateau fractures: retrospective analysis of 98 cases.

    PubMed

    Abdel-Hamid, Mohamed Zaki; Chang, Chung-Hsun; Chan, Yi-Sheng; Lo, Yang-Pin; Huang, Jau-Wen; Hsu, Kuo-Yao; Wang, Ching-Jen

    2006-06-01

    This investigation arthroscopically assesses the frequency of soft tissue injury in tibial plateau fracture according to the severity of fracture patterns. We hypothesized that use of arthroscopy to evaluate soft tissue injury in tibial plateau fractures would reveal a greater number of associated injuries than have previously been reported. From March 1996 to December 2003, 98 patients with closed tibial plateau fractures were treated with arthroscopically assisted reduction and osteosynthesis, with precise diagnosis and management of associated soft tissue injuries. Arthroscopic findings for associated soft tissue injuries were recorded, and the relationship between fracture type and soft tissue injury was then analyzed. The frequency of associated soft tissue injury in this series was 71% (70 of 98). The menisci were injured in 57% of subjects (56 in 98), the anterior cruciate ligament (ACL) in 25% (24 of 98), the posterior cruciate ligament (PCL) in 5% (5 of 98), the lateral collateral ligament (LCL) in 3% (3 of 98), the medial collateral ligament (MCL) in 3% (3 of 98), and the peroneal nerve in 1% (1 of 98); none of the 98 patients exhibited injury to the arteries. No significant association was noted between fracture type and incidence of meniscus, PCL, LCL, MCL, artery, and nerve injury. However, significantly higher injury rates for the ACL were observed in type IV and VI fractures. Soft tissue injury was associated with all types of tibial plateau fracture. Menisci (peripheral tear) and ACL (bony avulsion) were the most commonly injured sites. A variety of soft tissue injuries are common with tibial plateau fracture; these can be diagnosed with the use of an arthroscope. Level III, diagnostic study.

  5. Long-term anabolic effects of prostaglandin-E2 on tibial diaphyseal bone in male rats

    NASA Technical Reports Server (NTRS)

    Jee, Webster S. S.; Ke, Hua Zhu; Li, Xiao Jian

    1991-01-01

    The effects of long-term prostaglandin E2 (PGE2) on tibial diaphyseal bone were studied in 7-month-old male Sprague-Dawley rats given daily subcutaneous injections of 0, 1, 3 and 6 mg PGE2/kg/day for 60, 120 and 180 days. The tibial shaft was measured by single photon absorptiometry and dynamic histomorphometric analyses were performed on double-fluorescent labeled undecalcified tibial diaphyseal bone samples. Exogenous PGE2 administration produced the following transient changes in a dose-response manner between zero and 60 days: (1) increased bone width and mineral density; (2) increased total tissue and total bone areas; (3) decreased marrow area; (4) increased periosteal and corticoendosteal lamellar bone formation; (5) activated corticoendosteal lamellar and woven trabecular bone formation; and (6) activated intracortical bone remodeling. A new steady-state of increased tibial diaphyseal bone mass and elevated bone activities were observed from day 60 onward. The elevated bone mass level attained after 60 days of PGE2 treatment was maintained at 120 and 180 days. These observations indicate that the powerful anabolic effects of PGE2 will increase both periosteal and corticoendosteal bone mass and sustain the transient increase in bone mass with continuous daily administration of PGE2.

  6. Cemented tibial component fixation performs better than cementless fixation: a randomized radiostereometric study comparing porous-coated, hydroxyapatite-coated and cemented tibial components over 5 years.

    PubMed

    Carlsson, Ake; Björkman, Anders; Besjakov, Jack; Onsten, Ingemar

    2005-06-01

    The question whether the tibial component of a total knee arthroplasty should be fixed to bone with or without bone cement has not yet been definitely answered. We studied movements between the tibial component and bone by radiostereometry (RSA) in total knee replacement (TKR) for 3 different types of fixation: cemented fixation (C-F), uncemented porous fixation (UC-F) and uncemented porous hydroxyapatite fixation (UCHA-F). 116 patients with osteoarthrosis, who had 146 TKRs, were included in 2 randomized series. The first series included 86 unilateral TKRs stratified into 1 of the 3 types of fixation. The second series included 30 patients who had simultaneous bilateral TKR surgery, and who were stratified into 3 subgroups of pairwise comparisons of the 3 types of fixation. After 5 years 2 knees had been revised, neither of which were due to loosening. 1 UCHA-F knee in the unilateral series showed a large and continuous migration and a poor clinical result, and is a pending failure. The C-F knees rotated and migrated less than UC-F and UCHA-F knees over 5 years. UCHA-F migrated less than UC-F after 1 year. Cementing of the tibial component offers more stable bone-implant contact for 5 years compared to uncemented fixation. When using uncemented components, however, there is evidence that augmenting a porous surface with hydroxyapatite may mean less motion between implant and bone after the initial postoperative year.

  7. Etiologic factors in the development of medial tibial stress syndrome: a review of the literature.

    PubMed

    Tweed, Jo L; Avil, Steven J; Campbell, Jackie A; Barnes, Mike R

    2008-01-01

    Medial tibial stress syndrome is a type of exercise-induced leg pain that is common in recreational and competitive athletes. Although various studies have attempted to find the exact pathogenesis of this common condition, it remains unknown. Various theories in literature from 1976 to 2006 were reviewed using key words. Until recently, inflammation of the periosteum due to excessive traction was thought to be the most likely cause of medial tibial stress syndrome. This periostitis has been hypothesized by some authors to be caused by the tearing away of the muscle fibers at the muscle-bone interface, although there are several suggestions as to which, if any, muscle is responsible. Recent studies have supported the view that medial tibial stress syndrome is not an inflammatory process of the periosteum but instead a stress reaction of bone that has become painful.

  8. [Reconstruction of tangential and circular infected bone defects].

    PubMed

    Schmidt, H G; Neikes, M; Zimmer, W

    1987-12-01

    In the treatment of bone infections the reconstruction and rehabilitation of bone defects is a problem that often requires treatment secondary to curative treatment of the infection. For the reconstruction of smaller and more extensive defects we used predominantly (92.7%) autogenous (autologous) untreated spongiosa and in only 7% of the cases allogenic (homologous) spongiosa from an organ bank, this being added if necessary. Recently the additionally introduced vascularized bone chip has become a useful extension of the therapy concept. The problems and complications of defect reconstruction are demonstrated for 705 cases of bone infection with 472 defects of different sizes, based on a comprehensive classification with defect calculation. Surgical technical approach and special aspects of after-treatment are described, as well as the results for every group of cases. We achieved stability and freedom from infection in a total of 93.7% of the patients. As was to be expected, the problems grow with the size of the defect. Particularly problematic are joint infections with adjacent extensive circular defect.

  9. ß-TCP bone substitutes in tibial plateau depression fractures.

    PubMed

    Rolvien, Tim; Barvencik, Florian; Klatte, Till Orla; Busse, Björn; Hahn, Michael; Rueger, Johannes Maria; Rupprecht, Martin

    2017-10-01

    The use of beta-tricalciumphospate (ß-TCP, Cerasorb®) ceramics as an alternative for autologous bone-grafting has been outlined previously, however with no study focusing on both clinical and histological outcomes of ß-TCP application in patients with multi-fragment tibial plateau fractures. The aim of this study was to analyze the long-term results of ß-TCP in patients with tibial plateau fractures. 52 patients were included in this study. All patients underwent open surgery with ß-TCP block or granulate application. After a mean follow-up of 36months (14-64months), the patients were reviewed. Radiography and computed-tomography were performed, while the Rasmussen score was obtained for clinical outcome. Furthermore, seven patients underwent biopsy during hardware removal, which was subsequently analyzed by histology and backscattered electron microscopy (BSEM). An excellent reduction with two millimeters or less of residual incongruity was achieved in 83% of the patients. At follow-up, no further changes occurred and no nonunions were observed. Functional outcome was good to excellent in 82%. Four patients underwent revision surgery due to reasons unrelated to the bone substitute material. Histologic analyses indicated that new bone was built around the ß-TCP-grafts, however a complete resorption of ß-TCP was not observed. ß-TCP combined with internal fixation represents an effective and safe treatment of tibial plateau depression fractures with good functional recovery. While its osteoconductivity seems to be successful, the biological degradation and replacement of ß-TCP is less pronounced in humans than previous animal studies have indicated. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Hardwood log defect photographic database, software and user's guide

    Treesearch

    R. Edward Thomas

    2009-01-01

    Computer software and user's guide for Hardwood Log Defect Photographic Database. The database contains photographs and information on external hardwood log defects and the corresponding internal characteristics. This database allows users to search for specific defect types, sizes, and locations by tree species. For every defect, the database contains photos of...

  11. [Effects of posterior tibial slope on non-contact anterior cruciate ligament rupture and stability of anterior cruciate ligament rupture knee].

    PubMed

    Yue, De-bo; E, Sen; Wang, Bai-liang; Wang, Wei-guo; Guo, Wan-shou; Zhang, Qi-dong

    2013-05-07

    To retrospectively explore the correlation between anterior cruciate ligament (ACL)-ruptured knees, stability of ACL-rupture knee and posterior tibial slope (PTS). From January 2008 to October 2012, 150 knees with ACL rupture underwent arthroscopic surgery for ACL reconstruction. A control group was established for subjects undergoing arthroscopic surgery without ACL rupture during the same period. PTS was measured on a digitalized lateral radiograph. Lachman and mechanized pivot shift tests were performed for assessing the stability of knee. There was significant difference (P = 0.007) in PTS angle between the patients with ACL rupture (9.5 ± 2.2 degrees) and the control group (6.6 ± 1.8 degrees). Only among females, increased slope of tibial plateau had effect on the Lachman test. There was a higher positive rate of pivot shift test in patients of increased posterior slope in the ACL rupture group. Increased posterior tibial slope (>6.6) appears to contribute to non-contact ACL injuries in females. And the changes of tibial slope have no effect upon the Lachman test. However, large changes in tibial slope affect pivot shift.

  12. Inspection of lithographic mask blanks for defects

    DOEpatents

    Sommargren, Gary E.

    2001-01-01

    A visible light method for detecting sub-100 nm size defects on mask blanks used for lithography. By using optical heterodyne techniques, detection of the scattered light can be significantly enhanced as compared to standard intensity detection methods. The invention is useful in the inspection of super-polished surfaces for isolated surface defects or particulate contamination and in the inspection of lithographic mask or reticle blanks for surface defects or bulk defects or for surface particulate contamination.

  13. Effect of dose and size on defect engineering in carbon cluster implanted silicon wafers

    NASA Astrophysics Data System (ADS)

    Okuyama, Ryosuke; Masada, Ayumi; Shigematsu, Satoshi; Kadono, Takeshi; Hirose, Ryo; Koga, Yoshihiro; Okuda, Hidehiko; Kurita, Kazunari

    2018-01-01

    Carbon-cluster-ion-implanted defects were investigated by high-resolution cross-sectional transmission electron microscopy toward achieving high-performance CMOS image sensors. We revealed that implantation damage formation in the silicon wafer bulk significantly differs between carbon-cluster and monomer ions after implantation. After epitaxial growth, small and large defects were observed in the implanted region of carbon clusters. The electron diffraction pattern of both small and large defects exhibits that from bulk crystalline silicon in the implanted region. On the one hand, we assumed that the silicon carbide structure was not formed in the implanted region, and small defects formed because of the complex of carbon and interstitial silicon. On the other hand, large defects were hypothesized to originate from the recrystallization of the amorphous layer formed by high-dose carbon-cluster implantation. These defects are considered to contribute to the powerful gettering capability required for high-performance CMOS image sensors.

  14. Atypical presentation of popliteal artery entrapment syndrome: involvement of the anterior tibial artery.

    PubMed

    Bou, Steven; Day, Carly

    2014-11-01

    Popliteal artery entrapment syndrome (PAES) is a rare condition that should be suspected in a young patient with exertional lower extremity pain. We report the case of an 18-year-old female volleyball player with bilateral exertional lower extremity pain who had been previously diagnosed with tendinitis and periostitis. Diagnostic studies showed entrapment of the left popliteal artery and the left anterior tibial artery. To our knowledge, there has only been 1 previous report of anterior tibial artery involvement in PAES. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  15. Effects of directly autotransplanted tibial bone marrow aspirates on bone regeneration and osseointegration of dental implants.

    PubMed

    Payer, Michael; Lohberger, Birgit; Strunk, Dirk; Reich, Karoline M; Acham, Stephan; Jakse, Norbert

    2014-04-01

    Aim of the pilot trial was to evaluate applicability and effects of directly autotransplanted tibial bone marrow (BM) aspirates on the incorporation of porous bovine bone mineral in a sinus lift model and on the osseointegration of dental implants. Six edentulous patients with bilaterally severely resorbed maxillae requiring sinus augmentation and implant treatment were included. During surgery, tibial BM was harvested and added to bone substitute material (Bio-Oss(®) ) at the randomly selected test site. At control sites, augmentation was performed with Bio-Oss(®) alone. The cellular content of each BM aspirate was checked for multipotency and surface antigen expression as quality control. Histomorphometric analysis of biopsies from the augmented sites after 3 and 6 months (during implantation) was used to evaluate effects on bone regeneration. Osseointegration of implants was evaluated with Periotest(®) and radiographic means. Multipotent cellular content in tibial BM aspirates was comparable to that in punctures from the iliac crest. No significant difference in amount of new bone formation and the integration of bone substitute particles was detected histomorphometrically. Periotest(®) values and radiographs showed successful osseointegration of inserted implants at all sites. Directly autotransplanted tibial BM aspirates did not show beneficial regenerative effects in the small study population (N = 6) of the present pilot trial. However, the proximal tibia proved to be a potential donor site for small quantities of BM. Future trials should clarify whether concentration of tibial BM aspirates could effect higher regenerative potency. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Incidence of complications associated with tibial tuberosity advancement in Boxer dogs.

    PubMed

    de Lima Dantas, Brigite; Sul, Rui; Parkin, Tim; Calvo, Ignacio

    2016-01-01

    To retrospectively review and describe the incidence of complications associated with tibial tuberosity advancement (TTA) surgical procedures in a group of Boxer dogs (n = 36 stifles) and compare the data with a non-Boxer control population (n = 271 stifles). Retrospective analysis of medical records to identify all dogs that underwent TTA surgery due to cranial cruciate ligament disease. These records were categorized into two groups: Boxer dogs and non-Boxer dogs (controls - all other breeds). Of the 307 stifles included, 69 complications were reported in 58 joints. The complication rate differed significantly for Boxer dogs (16/36 stifles) and non-Boxer dogs (42/271 stifles), corresponding to an odds ratio of 5.8 (confidence interval: 1.96-17.02; p-value <0.001). Boxer dogs were more likely to undergo revision surgery and to develop multiple complications. The incidence of tibial tuberosity fractures requiring surgical repair (2/36 versus 1/271) and incisional infections requiring antibiotic treatment (three in each group) was significantly higher in the Boxer group. Boxer dogs had more major and multiple complications after TTA surgery than the control non-Boxer group; these complications included higher rates of revision surgery, tibial tuberosity fractures requiring stabilization, and infection related complications. The pertinence and value of breed-specific recommendations for cranial cruciate ligament disease appears to be a subject worthy of further investigation.

  17. Os tibiale externum or sesamoid in the tendon of tibialis posterior.

    PubMed

    Bareither, D J; Muehleman, C M; Feldman, N J

    1995-01-01

    From a total of 165 foot and lower leg cadaveric specimens, 38 specimens were selected by palpation of the region of the tuberosity of the navicular for the possible presence of an accessory bone. Specimens were radiographed and dissected to reveal the presence of an accessory bone and its relationship to the tibialis posterior tendon. Nineteen of the specimens exhibited hypertrophy of the tibialis posterior tendon and 19 specimens exhibited an accessory bone. Specimens exhibiting an accessory bone were divided into two categories. In one group, the accessory bone was located in the tibialis posterior tendon prior to its division and was separated from the tuberosity by at least 3 mm. In the other group, the accessory bone was located in the main segment of the tibialis posterior tendon, connected to the tuberosity of the navicular by fibrous tissue, and, in some cases, exhibited a central cavity between the accessory bone and tuberosity. The accessory bone of specimens in the first group was considered to be a sesamoid in the tibialis posterior tendon and the accessory bone in the second group was an ossicle considered to be the os tibiale externum. Linking the os tibiale externum to the tibiale component of the primitive tetrapod foot rather than to the prehallux component eliminates the use of the term "prehallux" as an alternative name for this ossicle.

  18. EMG and tibial shock upon the first attempt at barefoot running.

    PubMed

    Olin, Evan D; Gutierrez, Gregory M

    2013-04-01

    As a potential means to decrease their risk of injury, many runners are transitioning into barefoot running. Habitually shod runners tend to heel-strike (SHS), landing on their heel first, while barefoot runners tend to mid-foot or toe-strike (BTS), landing flat-footed or on the ball of their foot before bringing down the rest of the foot including the heel. This study compared muscle activity, tibial shock, and knee flexion angle in subjects between shod and barefoot conditions. Eighteen habitually SHS recreational runners ran for 3 separate 7-minute trials, including SHS, barefoot heel-strike (BHS), and BTS conditions. EMG, tibial shock, and knee flexion angle were monitored using bipolar surface electrodes, an accelerometer, and an electrogoniometer, respectively. A one-way MANOVA for repeated measures was conducted and several significant changes were noted between SHS and BTS, including significant increases in average EMG of the medial gastrocnemius (p=.05), average and peak tibial shock (p<.01), and the minimum knee flexion angle (p<.01). Based on our data, the initial change in mechanics may have detrimental effects on the runner. While it has been argued that BTS running may ultimately be less injurious, these data indicate that habitually SHS runners who choose to transition into a BTS technique must undertake the process cautiously. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Estimates of Tibial Shock Magnitude in Men and Women at the Start and End of a Military Drill Training Program.

    PubMed

    Rice, Hannah M; Saunders, Samantha C; McGuire, Stephen J; O'Leary, Thomas J; Izard, Rachel M

    2018-03-26

    Foot drill is a key component of military training and is characterized by frequent heel stamping, likely resulting in high tibial shock magnitudes. Higher tibial shock during running has previously been associated with risk of lower limb stress fractures, which are prevalent among military populations. Quantification of tibial shock during drill training is, therefore, warranted. This study aimed to provide estimates of tibial shock during military drill in British Army Basic training. The study also aimed to compare values between men and women, and to identify any differences between the first and final sessions of training. Tibial accelerometers were secured on the right medial, distal shank of 10 British Army recruits (n = 5 men; n = 5 women) throughout a scheduled drill training session in week 1 and week 12 of basic military training. Peak positive accelerations, the average magnitude above given thresholds, and the rate at which each threshold was exceeded were quantified. Mean (SD) peak positive acceleration was 20.8 (2.2) g across all sessions, which is considerably higher than values typically observed during high impact physical activity. Magnitudes of tibial shock were higher in men than women, and higher in week 12 compared with week 1 of training. This study provides the first estimates of tibial shock magnitude during military drill training in the field. The high values suggest that military drill is a demanding activity and this should be considered when developing and evaluating military training programs. Further exploration is required to understand the response of the lower limb to military drill training and the etiology of these responses in the development of lower limb stress fractures.

  20. Moore I postero-medial articular tibial fracture in alpine skiers: Surgical management and return to sports activity.

    PubMed

    Morin, Vincent; Pailhé, Régis; Sharma, Akash; Rouchy, René-Christopher; Cognault, Jérémy; Rubens-Duval, Brice; Saragaglia, Dominique

    2016-06-01

    Over the past 10 years, like many authors, we observed an increasing number of Moore I tibial plateau fractures related to alpine skiing for which the surgeon may face difficult choices regarding surgical approach and fixation means. Some authors have recently been suggesting a posterior approach associated to open reduction and osteosynthesis by a buttress plate. But in our knowledge there is no specific study on sports activity recovery after Moore I tibial fractures. The aim of this work was to assess sports activities and clinical outcomes after surgically treated Moore I tibial plateau fractures in an athletic population of skiers. We conducted a prospective case series between 2012 and 2014. This included fifteen patients aged 39.6±7 years whom presented with a Moore I tibial plateau fracture during a skiing accident. 12 cases (80%) presented with an associated tibial spine fracture. Treatment consisted of a standard antero-medial approach, with a medial para patellar arthrotomy to allow direct visualisation of articular reduction and spinal fixation. Two or three 6.5mm long cancellous bone screws were placed antero-posteriorly so as to ensure perfect compression of the fracture site. Radiological and functional results were assessed by an independent observer (Lysholm-Tegner, UCLA, KOOS scores) at the longest follow-up. Mean follow-up was 18.2±6 months (12-28). An immediate postoperative anatomical reduction was achieved in all cases and remained stable in time. At last follow-up Lysholm mean score was 85±14 points (59-100), UCLA score was 7.3±1.6 (4-10) and Tegner score was 4.6±1.3 (3-6). Mean KOOS score was 77±15 (54-97). 87% of patients had resumed their skiing activity and 93% were satisfied or very satisfied from their post-operative surgical outcome. We observed no pseudarthrosis or secondary varus displacement. In our series 87% of patients had resumed back to their sporting activities. Surgical management of Moore I tibial plateau fractures by

  1. Comparison of the size of persistent foramen ovale and atrial septal defects in divers with shunt-related decompression illness and in the general population.

    PubMed

    Wilmshurst, Peter T; Morrison, W Lindsay; Walsh, Kevin P

    2015-06-01

    Decompression illness (DCI) is associated with a right-to-left shunt, such as persistent foramen ovale (PFO), atrial septal defect (ASD) and pulmonary arteriovenous malformations. About one-quarter of the population have a PFO, but considerably less than one-quarter of divers suffer DCI. Our aim was to determine whether shunt-related DCI occurs mainly or entirely in divers with the largest diameter atrial defects. Case control comparison of diameters of atrial defects (PFO and ASD) in 200 consecutive divers who had transcatheter closure of an atrial defect following shunt-related DCI and in an historic group of 263 individuals in whom PFO diameter was measured at post-mortem examination. In the divers who had experienced DCI, the median atrial defect diameter was 10 mm and the mean (standard deviation) was 9.9 (3.6) mm. Among those in the general population who had a PFO, the median diameter was 5 mm and mean was 4.9 (2.6) mm. The difference between the two groups was highly significant (P < 0.0001). Of divers with shunt-related DCI, 101 (50.5%) had an atrial defect 10 mm diameter or larger, but only 1.3% of the general population studied had a PFO that was 10 mm diameter of larger. The risk of a diver suffering DCI is related to the size of the atrial defect rather than just the presence of a defect.

  2. Distal tibial pilon fractures (AO/OTA type B, and C) treated with the external skeletal and minimal internal fixation method.

    PubMed

    Milenković, Sasa; Mitković, Milorad; Micić, Ivan; Mladenović, Desimir; Najman, Stevo; Trajanović, Miroslav; Manić, Miodrag; Mitković, Milan

    2013-09-01

    Distal tibial pilon fractures include extra-articular fractures of the tibial metaphysis and the more severe intra-articular tibial pilon fractures. There is no universal method for treating distal tibial pilon fractures. These fractures are treated by means of open reduction, internal fixation (ORIF) and external skeletal fixation. The high rate of soft-tissue complications associated with primary ORIF of pilon fractures led to the use of external skeletal fixation, with limited internal fixation as an alternative technique for definitive management. The aim of this study was to estimate efficacy of distal tibial pilon fratures treatment using the external skeletal and minimal internal fixation method. We presented a series of 31 operated patients with tibial pilon fractures. The patients were operated on using the method of external skeletal fixation with a minimal internal fixation. According to the AO/OTA classification, 17 patients had type B fracture and 14 patients type C fractures. The rigid external skeletal fixation was transformed into a dynamic external skeletal fixation 6 weeks post-surgery. This retrospective study involved 31 patients with tibial pilon fractures, average age 41.81 (from 21 to 60) years. The average follow-up was 21.86 (from 12 to 48) months. The percentage of union was 90.32%, nonunion 3.22% and malunion 6.45%. The mean to fracture union was 14 (range 12-20) weeks. There were 4 (12.19%) infections around the pins of the external skeletal fixator and one (3.22%) deep infections. The ankle joint arthrosis as a late complication appeared in 4 (12.90%) patients. All arthroses appeared in patients who had type C fractures. The final functional results based on the AOFAS score were excellent in 51.61%, good in 32.25%, average in 12.90% and bad in 3.22% of the patients. External skeletal fixation and minimal internal fixation of distal tibial pilon fractures is a good method for treating all types of inta-articular pilon fractures. In

  3. Bioprosthetics and repair of complex aerodigestive defects

    PubMed Central

    Udelsman, Brooks; Mathisen, Douglas J.

    2018-01-01

    Aerodigestive defects involving the trachea, bronchi and esophagus are a result of prolonged intubation, operative complications, congenital defects, trauma, radiation and neoplastic disease. The vast majority of these defects may be repaired primarily. Rarely, due the size of the defect, underlying complexity, or unfavorable patient characteristics, primary repair is not possible. One alternative to primary repair is bioprosthetic repair. Materials such as acellular dermal matrix and aortic homograft have been used in a variety of applications, including closure of tracheal, bronchial and esophageal defects. Herein, we review the use of bioprosthetics in the repair of aerodigestive defects, along with the unique advantages and disadvantages of these repairs. PMID:29707507

  4. Postoperative weight bearing and patient reported outcomes at one year following tibial plateau fractures.

    PubMed

    Thewlis, Dominic; Fraysse, Francois; Callary, Stuart A; Verghese, Viju Daniel; Jones, Claire F; Findlay, David M; Atkins, Gerald J; Rickman, Mark; Solomon, Lucian B

    2017-07-01

    results of tibial plateau fracture and may therefore be safe for postoperative management. These findings should be taken in context of the sample size, which was not sufficient for sub-group analysis to investigate the role of impaction grafting. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. In vivo tibial stiffness is maintained by whole bone morphology and cross-sectional geometry in growing female mice

    PubMed Central

    Main, Russell P.; Lynch, Maureen E.; van der Meulen, Marjolein C.H.

    2010-01-01

    Whole bone morphology, cortical geometry, and tissue material properties modulate skeletal stresses and strains that in turn influence skeletal physiology and remodeling. Understanding how bone stiffness, the relationship between applied load and tissue strain, is regulated by developmental changes in bone structure and tissue material properties is important in implementing biophysical strategies for promoting healthy bone growth and preventing bone loss. The goal of this study was to relate developmental patterns of in vivo whole bone stiffness to whole bone morphology, cross-sectional geometry, and tissue properties using a mouse axial loading model. We measured in vivo tibial stiffness in three age groups (6wks, 10wks, 16wks old) of female C57Bl/6 mice during cyclic tibial compression. Tibial stiffness was then related to cortical geometry, longitudinal bone curvature, and tissue mineral density using microcomputed tomography (microCT). Tibial stiffness and the stresses induced by axial compression were generally maintained from 6 to 16wks of age. Growth-related increases in cortical cross-sectional geometry and longitudinal bone curvature had counteracting effects on induced bone stresses and, therefore, maintained tibial stiffness similarly with growth. Tissue mineral density increased slightly from 6 to 16wks of age, and although the effects of this increase on tibial stiffness were not directly measured, its role in the modulation of whole bone stiffness was likely minor over the age range examined. Thus, whole bone morphology, as characterized by longitudinal curvature, along with cortical geometry, plays an important role in modulating bone stiffness during development and should be considered when evaluating and designing in vivo loading studies and biophysical skeletal therapies. PMID:20673665

  6. Open wedge high tibial osteotomies: Calcium-phosphate ceramic spacer versus autologous bonegraft.

    PubMed

    Gouin, F; Yaouanc, F; Waast, D; Melchior, B; Delecrin, J; Passuti, N

    2010-10-01

    Valgus tibial osteotomy (VTO) is a well-known procedure for the treatment of medial compartment femoro-tibial osteoarthritis. Good and very good results have been reported with calcium phosphate wedges, which avoid the inconveniences of autologous grafts use. The hypothesis of this study is that with equivalent results in the treatment of osteoarthritis of the knee, the use of calcium phosphate wedges (BMCaPh) to fill the bone defect created by osteotomy would result in fewer specific complications and less pain associated with autologous grafts (AUTO) harvesting. This prospective, controlled, randomised study included one arm that received a macroporous, biphasic calcium phosphate wedge (BMCaPh group) and one arm that received an autologous tricortical graft (AUTO group) for filling. The same plate with locked screws was used for fixation in all cases. All patients underwent at least two years of clinical and radiographic post-operative follow-up. Forty patients were included. Loss of correction occurred in six of the twenty-two patients in the BMCaPh group (27%), resulting in three early surgical revisions, compared to one loss of correction in the AUTO group. Lateral cortical hinge tears were a risk factor for loss of correction for the entire cohort and in the BMCaPh group. (relative risk 13.3 [1.9-92]. Moreover, union took significantly longer and pain lasted significantly longer in the BMCaPh group, although results were comparable at 6 months. A significant number of undesirable events (loss of correction) occurred in this study, limiting the number of included patients. Nevertheless, the results show that although there was no difference in the two groups for overall complications, number of revisions all causes combined, or clinical results, filling with BMCaPh was less tolerated and increased the risk of loss of correction when local mechanical conditions of the knee were unfavourable (lateral cortical hinge tears). Moreover, although it is not possible

  7. Large tibial geode, which developed several years after a left medial Oxford unicondylar knee arthroplasty, treated with curettage and bone grafting.

    PubMed

    Curran, Matthew K; Murray, James R

    2018-05-14

    Tibial geodes are rare, and usually reported in association with rheumatoid arthritis. This case study reported the rare occurrence of a tibial geode in association with a left unicondylar knee arthroplasty (UKA). The patient, a 55-year-old male, was initially pleased with his UKA, which was performed at another institution. However, just over one year after the operation he began experiencing pain and discomfort. He did not present to the current institution until he was six years after UKA. This pain was movement and weight bearing related, although he still managed to maintain an active lifestyle working as a builder. After several years of follow-up, a computed tomography (CT) scan showed a significant increase in size of the geode. The patient initially did not want to undergo further surgery, as he was self-employed, but it was decided, in conjunction with the patient, that it was time to operate because the stability of the prothesis was in question. Transcortical and retrograde curettage of the geode was performed and one and a half femoral head allografts were used to fill the geode. Follow-up since the operation showed good infilling of the geode and bone remodelling, with resolution of symptoms at 12 months. This case report was the first to report a symptomatic tibial geode in close association with UKA, which did not lead to revision surgery to total knee arthroplasty (TKA), but instead was successfully treated with currettage and bone grafting. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Open Tibial Inlay PCL Reconstruction: Surgical Technique and Clinical Outcomes.

    PubMed

    Vellios, Evan E; Jones, Kristofer J; McAllister, David R

    2018-06-01

    To review the current literature on clinical outcomes following open tibial inlay posterior cruciate ligament (PCL) reconstruction and provide the reader with a detailed description of the author's preferred surgical technique. Despite earlier biomechanical studies which demonstrated superiority of the PCL inlay technique when compared to transtibial techniques, recent longitudinal cohort studies have shown no significant differences in clinical or functional outcomes at 10-year follow-up. Furthermore, no significant clinical differences have been shown between graft types used and/or single- versus double-bundle reconstruction methods. The optimal treatment for the PCL-deficient knee remains unclear. Open tibial inlay PCL reconstruction is safe, reproducible, and avoids the "killer turn" that may potentially lead to graft weakening and failure seen in transtibial reconstruction methods. No significant differences in subjective outcomes or clinical laxity have been shown between single-bundle versus double-bundle reconstruction methods.

  9. Influence of Casting Defects on S- N Fatigue Behavior of Ni-Al Bronze

    NASA Astrophysics Data System (ADS)

    Sarkar, Aritra; Chakrabarti, Abhishek; Nagesha, A.; Saravanan, T.; Arunmuthu, K.; Sandhya, R.; Philip, John; Mathew, M. D.; Jayakumar, T.

    2015-02-01

    Nickel-aluminum bronze (NAB) alloys have been used extensively in marine applications such as propellers, couplings, pump casings, and pump impellers due to their good mechanical properties such as tensile strength, creep resistance, and corrosion resistance. However, there have been several instances of in-service failure of the alloy due to high cycle fatigue (HCF). The present paper aims at characterizing the casting defects in this alloy through X-ray radiography and X-ray computed tomography into distinct defect groups having particular defect size and location. HCF tests were carried out on each defect group of as-cast NAB at room temperature by varying the mean stress. A significant decrease in the HCF life was observed with an increase in the tensile mean stress, irrespective of the defect size. Further, a considerable drop in the HCF life was observed with an increase in the size of defects and proximity of the defects to the surface. However, the surface proximity indicated by location of the defect in the sample was seen to override the influence of defect size and maximum cyclic stress. This leads to huge scatter in S- N curve. For a detailed quantitative analysis of defect size and location, an empirical model is developed which was able to minimize the scatter to a significant extent. Further, a concept of critical distance is proposed, beyond which the defect would not have a deleterious consequence on the fatigue behavior. Such an approach was found to be suitable for generating S- N curves for cast NAB.

  10. The Effect of Arch Drop on Tibial Rotation and Tibiofemoral Contact Stress in Postpartum Women.

    PubMed

    Rabe, Kaitlin; Segal, Neil A; Waheed, Saphia; Anderson, Donald D

    2018-04-26

    Women are at greater risk for knee osteoarthritis and numerous other lower limb musculoskeletal disorders. Arch drop during pregnancy and the resultant excessive pronation of the feet may alter loading patterns and contribute to the greater prevalence of knee osteoarthritis in women. To determine the effect of arch drop on tibial rotation and tibiofemoral contact stress. Interventional study with internal control. Biomechanics laboratory. Eleven postpartum women (age 33.4 ± 5.3 years, body mass 76.1 ± 13.5 kg) who had lost arch height with pregnancy in a previous study. Subjects underwent standing computed tomography (SCT) with their knees in a 20° fixed-flexed position with and without semirigid arch supports to reconstitute prepregnancy arch height. Magnetic resonance imaging of the knee was acquired at a flexion angle equivalent to that of SCT. Bone and cartilage were manually segmented on the magnetic resonance images and segmented surfaces were registered to the 3-dimensional SCT image sets for the arch-supported and -unsupported conditions. These models were used to measure changes in tibial rotation, as well as to estimate contact stress in the medial and lateral tibiofemoral compartments, using computational methods. Change in tibial rotation and tibiofemoral contact stress with arch drop. Arch drop resulted in a mean tibial internal rotation of 0.75 ± 1.33° (P < .05). Changes in mean or peak contact stress were not detected. Arch drop causes internal tibial rotation, resulting in a shift in the tibiofemoral articulation. An associated increase in contact stress was not detected. Internal rotation of the tibia increases stress on the anterior cruciate ligament and menisci, potentially explaining the greater prevalence of knee disorders in postpartum women. Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  11. A modified technique to reduce tibial keel cutting errors during an Oxford unicompartmental knee arthroplasty.

    PubMed

    Inui, Hiroshi; Taketomi, Shuji; Tahara, Keitarou; Yamagami, Ryota; Sanada, Takaki; Tanaka, Sakae

    2017-03-01

    Bone cutting errors can cause malalignment of unicompartmental knee arthroplasties (UKA). Although the extent of tibial malalignment due to horizontal cutting errors has been well reported, there is a lack of studies evaluating malalignment as a consequence of keel cutting errors, particularly in the Oxford UKA. The purpose of this study was to examine keel cutting errors during Oxford UKA placement using a navigation system and to clarify whether two different tibial keel cutting techniques would have different error rates. The alignment of the tibial cut surface after a horizontal osteotomy and the surface of the tibial trial component was measured with a navigation system. Cutting error was defined as the angular difference between these measurements. The following two techniques were used: the standard "pushing" technique in 83 patients (group P) and a modified "dolphin" technique in 41 patients (group D). In all 123 patients studied, the mean absolute keel cutting error was 1.7° and 1.4° in the coronal and sagittal planes, respectively. In group P, there were 22 outlier patients (27 %) in the coronal plane and 13 (16 %) in the sagittal plane. Group D had three outlier patients (8 %) in the coronal plane and none (0 %) in the sagittal plane. Significant differences were observed in the outlier ratio of these techniques in both the sagittal (P = 0.014) and coronal (P = 0.008) planes. Our study demonstrated overall keel cutting errors of 1.7° in the coronal plane and 1.4° in the sagittal plane. The "dolphin" technique was found to significantly reduce keel cutting errors on the tibial side. This technique will be useful for accurate component positioning and therefore improve the longevity of Oxford UKAs. Retrospective comparative study, Level III.

  12. Delivery of S1P Receptor-Targeted Drugs via Biodegradable Polymer Scaffolds Enhances Bone Regeneration in a Critical Size Cranial Defect*

    PubMed Central

    Das, Anusuya; Tanner, Shaun; Barker, Daniel A.; Green, David; Botchwey, Edward A.

    2014-01-01

    Biodegradable polymer scaffolds can be used to deliver soluble factors to enhance osseous remodeling in bone defects. To this end, we designed a poly(lactic-co-glycolic acid) (PLAGA) microsphere scaffold to sustain the release of FTY720, a selective agonist for sphingosine 1-phosphate (S1P) receptors. The microsphere scaffolds were created from fast degrading 50:50 PLAGA and/or from slow-degrading 85:15 PLAGA. Temporal and spatial regulation of bone remodeling depended on the use of appropriate scaffolds for drug delivery. The release profiles from the scaffolds were used to design an optimal delivery system to treat critical size cranial defects in a rodent model. The ability of local FTY720 delivery to maximize bone regeneration was evaluated with microcomputed tomography (microCT) and histology. Following 4 weeks of defect healing, FTY720 delivery from 85:15 PLAGA scaffolds resulted in a significant increase in bone volumes in the defect region compared to the controls. 85:15 microsphere scaffolds maintain their structural integrity over a longer period of time, and cause an initial burst release of FTY720 due to surface localization of the drug. This encourages cellular in-growth and an increase in new bone formation. PMID:23640833

  13. Delivery of S1P receptor-targeted drugs via biodegradable polymer scaffolds enhances bone regeneration in a critical size cranial defect.

    PubMed

    Das, Anusuya; Tanner, Shaun; Barker, Daniel A; Green, David; Botchwey, Edward A

    2014-04-01

    Biodegradable polymer scaffolds can be used to deliver soluble factors to enhance osseous remodeling in bone defects. To this end, we designed a poly(lactic-co-glycolic acid) (PLAGA) microsphere scaffold to sustain the release of FTY720, a selective agonist for sphingosine 1-phosphate (S1P) receptors. The microsphere scaffolds were created from fast degrading 50:50 PLAGA and/or from slow-degrading 85:15 PLAGA. Temporal and spatial regulation of bone remodeling depended on the use of appropriate scaffolds for drug delivery. The release profiles from the scaffolds were used to design an optimal delivery system to treat critical size cranial defects in a rodent model. The ability of local FTY720 delivery to maximize bone regeneration was evaluated with micro-computed tomography (microCT) and histology. Following 4 weeks of defect healing, FTY720 delivery from 85:15 PLAGA scaffolds resulted in a significant increase in bone volumes in the defect region compared to the controls. A 85:15 microsphere scaffolds maintain their structural integrity over a longer period of time, and cause an initial burst release of FTY720 due to surface localization of the drug. This encourages cellular in-growth and an increase in new bone formation. Copyright © 2013 Wiley Periodicals, Inc.

  14. Tibial Bowing and Pseudarthrosis in Neurofibromatosis Type 1

    DTIC Science & Technology

    2015-01-01

    controlling for age and sex was used. However, there were no statistically significant differences between NF1 individuals with and without tibial...Dinorah Friedmann-Morvinski (The Salk Institute) presented a different model of glioblastoma in which tumors were induced from fully differentiated...a driver of Schwann cell tumorigenesis. Induction ofWnt signaling was sufficient to induce a transformed phenotype in human Schwann cells, while

  15. Epidemiology of metatarsal stress fractures versus tibial and femoral stress fractures during elite training.

    PubMed

    Finestone, Aharon; Milgrom, Charles; Wolf, Omer; Petrov, Kaloyan; Evans, Rachel; Moran, Daniel

    2011-01-01

    The training of elite infantry recruits takes a year or more. Stress fractures are known to be endemic in their basic training and the clinical presentation of tibial, femoral, and metatarsal stress fractures are different. Stress fracture incidence during the subsequent progressively more demanding training is not known. The study hypothesis was that after an adaptation period, the incidence of stress fractures during the course of 1 year of elite infantry training would fall in spite of the increasingly demanding training. Seventy-six male elite infantry recruits were followed for the development of stress fractures during a progressively more difficult training program composed of basic training (1 to 14 weeks), advanced training (14 to 26 weeks), and unit training (26 to 52 weeks). Subjects were reviewed regularly and those with clinical suspicion of stress fracture were assessed using bone scan and X-rays. The incidence of stress fractures was 20% during basic training, 14% during advanced training and 23% during unit training. There was a statistically significant difference in the incidence of tibial and femoral stress fractures versus metatarsal stress fractures before and after the completion of phase II training at week 26 (p=0.0001). Seventy-eight percent of the stress fractures during phases I and II training were either tibial or femoral, while 91% of the stress fractures in phase III training were metatarsal. Prior participation in ball sports (p=0.02) and greater tibial length (p=0.05) were protective factors for stress fracture. The study hypothesis that after a period of soldier adaptation, the incidence of stress fractures would decrease in spite of the increasingly demanding elite infantry training was found to be true for tibial and femoral fractures after 6 months of training but not for metatarsal stress fractures. Further studies are required to understand the mechanism of this difference but physicians and others treating stress fractures

  16. Role of high tibial osteotomy in chronic injuries of posterior cruciate ligament and posterolateral corner.

    PubMed

    Savarese, Eugenio; Bisicchia, Salvatore; Romeo, Rocco; Amendola, Annunziato

    2011-03-01

    High tibial osteotomy (HTO) is a surgical procedure used to change the mechanical weight-bearing axis and alter the loads carried through the knee. Conventional indications for HTO are medial compartment osteoarthritis and varus malalignment of the knee causing pain and dysfunction. Traditionally, knee instability associated with varus thrust has been considered a contraindication. However, today the indications include patients with chronic ligament deficiencies and malalignment, because an HTO procedure can change not only the coronal but also the sagittal plane of the knee. The sagittal plane has generally been ignored in HTO literature, but its modification has a significant impact on biomechanics and joint stability. Indeed, decreased posterior tibial slope causes posterior tibia translation and helps the anterior cruciate ligament (ACL)-deficient knee. Vice versa, increased tibial slope causes anterior tibia translation and helps the posterior cruciate ligament (PCL)-deficient knee. A review of literature shows that soft tissue procedures alone are often unsatisfactory for chronic posterior instability if alignment is not corrected. Since limb alignment is the most important factor to consider in lower limb reconstructive surgery, diagnosis and treatment of limb malalignment should not be ignored in management of chronic ligamentous instabilities. This paper reviews the effects of chronic posterior instability and tibial slope alteration on knee and soft tissues, in addition to planning and surgical technique for chronic posterior and posterolateral instability with HTO.

  17. Distinct hip and rearfoot kinematics in female runners with a history of tibial stress fracture.

    PubMed

    Milner, Clare E; Hamill, Joseph; Davis, Irene S

    2010-02-01

    Cross-sectional controlled laboratory study. To investigate the kinematics of the hip, knee, and rearfoot in the frontal and transverse planes in female distance runners with a history of tibial stress fracture. Tibial stress fractures are a common overuse injury in runners, accounting for up to half of all stress fractures. Abnormal kinematics of the lower extremity may contribute to abnormal musculoskeletal load distributions, leading to an increased risk of stress fractures. Thirty female runners with a history of tibial stress fracture were compared to 30 age-matched and weekly-running-distance-matched control subjects with no previous lower extremity bony injuries. Kinematic and kinetic data were collected using a motion capture system and a force platform, respectively, as subjects ran in the laboratory. Selected variables of interest were compared between the groups using a multivariate analysis of variance (MANOVA). Peak hip adduction and peak rearfoot eversion angles were greater in the stress fracture group compared to the control group. Peak knee adduction and knee internal rotation angles and all joint angles at impact peak were similar between the groups. Runners with a previous tibial stress fracture exhibited greater peak hip adduction and rearfoot eversion angles during the stance phase of running compared to healthy controls. A consequence of these mechanics may be altered load distribution within the lower extremity, predisposing individuals to stress fracture.

  18. Hindfoot Valgus following Interlocking Nail Treatment for Tibial Diaphysis Fractures: Can the Fibula Be Neglected?

    PubMed Central

    Uzun, Metin; Kara, Adnan; Adaş, Müjdat; Karslioğlu, Bülent; Bülbül, Murat; Beksaç, Burak

    2014-01-01

    Purpose. We evaluated whether intramedullary nail fixation for tibial diaphysis fractures with concomitant fibula fractures (except at the distal one-third level) managed conservatively with an associated fibula fracture resulted in ankle deformity and assessed the impact of the ankle deformity on lower extremity function. Methods. Sixty middle one-third tibial shaft fractures with associated fibular fractures, except the distal one-third level, were included in this study. All tibial shaft fractures were anatomically reduced and fixed with interlocking intramedullary nails. Fibular fractures were managed conservatively. Hindfoot alignment was assessed clinically. Tibia and fibular lengths were compared to contralateral measurements using radiographs. Functional results were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Foot and Ankle Disability Index Score (FADI). Results. Anatomic union, defined as equal length in operative and contralateral tibias, was achieved in 60 fractures (100%). Fibular shortening was identified in 42 fractures (68%). Mean fibular shortening was 1.2 cm (range, 0.5–2 cm). Clinical exams showed increased hindfoot valgus in 42 fractures (68%). The mean KOOS was 88.4, and the mean FADI score was 90. Conclusion. Fibular fractures in the middle or proximal one-third may need to be stabilized at the time of tibial intramedullary nail fixation to prevent development of hindfoot valgus due to fibular shortening. PMID:25544899

  19. Management of open tibial fractures – a regional experience

    PubMed Central

    Townley, WA; Nguyen, DQA; Rooker, JC; Dickson, JK; Goroszeniuk, DZ; Khan, MS; Camp, D

    2010-01-01

    INTRODUCTION The treatment of soft-tissue injuries associated with tibial diaphyseal fractures presents a clinical challenge that is best managed by a combined plastic and orthopaedic surgery approach. The current study was undertaken to assess early treatment outcomes and burden of service provision across five regional plastic surgery units in the South-West of England. SUBJECTS AND METHODS We conducted a prospective 6-month audit of open tibial diaphyseal fracture management in five plastic surgery units (Bristol, Exeter, Plymouth, Salisbury, Swansea) with a collective catchment of 9.2 million people. Detailed data were collected on patient demographics, injury pattern, surgical management and outcome followed to discharge. RESULTS The study group consisted of 55 patients (40 male, 15 female). Twenty-two patients presented directly to the emergency department at the specialist hospital (primary group), 33 patients were initially managed at a local hospital (tertiary group). The mean time from injury to soft tissue cover was significantly less (P < 0.001) in the primary group (3.6 ± 0.8 days) than the tertiary group (10.8 ± 2.2 days), principally due to a delay in referral in the latter group (5.4 ±1.7 days). Cover was achieved with 39 flaps (19 free, 20 local), eight split skin grafts. Nine wounds closed directly or by secondary intention. There were 11 early complications (20%) including one flap failure and four infections. The overall mean length of stay was 17.5 ± 2.8 days. CONCLUSIONS Multidisciplinary management of severe open tibial diaphyseal may not be feasible at presentation of injury depending on local hospital specialist services available. Our results highlight the need for robust assessment, triage and senior orthopaedic review in the early post-injury phase. However, broader improvements in the management of lower limb trauma will additionally require further development of combined specialist trauma centres. PMID:21047449

  20. Medial tibial pain: a dynamic contrast-enhanced MRI study.

    PubMed

    Mattila, K T; Komu, M E; Dahlström, S; Koskinen, S K; Heikkilä, J

    1999-09-01

    The purpose of this study was to compare the sensitivity of different magnetic resonance imaging (MRI) sequences to depict periosteal edema in patients with medial tibial pain. Additionally, we evaluated the ability of dynamic contrast-enhanced imaging (DCES) to depict possible temporal alterations in muscular perfusion within compartments of the leg. Fifteen patients with medial tibial pain were examined with MRI. T1-, T2-weighted, proton density axial images and dynamic and static phase post-contrast images were compared in ability to depict periosteal edema. STIR was used in seven cases to depict bone marrow edema. Images were analyzed to detect signs of compartment edema. Region-of-interest measurements in compartments were performed during DCES and compared with controls. In detecting periosteal edema, post-contrast T1-weighted images were better than spin echo T2-weighted and proton density images or STIR images, but STIR depicted the bone marrow edema best. DCES best demonstrated the gradually enhancing periostitis. Four subjects with severe periosteal edema had visually detectable pathologic enhancement during DCES in the deep posterior compartment of the leg. Percentage enhancement in the deep posterior compartment of the leg was greater in patients than in controls. The fast enhancement phase in the deep posterior compartment began slightly slower in patients than in controls, but it continued longer. We believe that periosteal edema in bone stress reaction can cause impairment of venous flow in the deep posterior compartment. MRI can depict both these conditions. In patients with medial tibial pain, MR imaging protocol should include axial STIR images (to depict bone pathology) with T1-weighted axial pre and post-contrast images, and dynamic contrast enhanced imaging to show periosteal edema and abnormal contrast enhancement within a compartment.

  1. Variation in tibial functionality and fracture susceptibility among healthy, young adults arises from the acquisition of biologically distinct sets of traits.

    PubMed

    Jepsen, Karl J; Evans, Rachel; Negus, Charles H; Gagnier, Joel J; Centi, Amanda; Erlich, Tomer; Hadid, Amir; Yanovich, Ran; Moran, Daniel S

    2013-06-01

    Physiological systems like bone respond to many genetic and environmental factors by adjusting traits in a highly coordinated, compensatory manner to establish organ-level function. To be mechanically functional, a bone should be sufficiently stiff and strong to support physiological loads. Factors impairing this process are expected to compromise strength and increase fracture risk. We tested the hypotheses that individuals with reduced stiffness relative to body size will show an increased risk of fracturing and that reduced strength arises from the acquisition of biologically distinct sets of traits (ie, different combinations of morphological and tissue-level mechanical properties). We assessed tibial functionality retrospectively for 336 young adult women and men engaged in military training, and calculated robustness (total area/bone length), cortical area (Ct.Ar), and tissue-mineral density (TMD). These three traits explained 69% to 72% of the variation in tibial stiffness (p < 0.0001). Having reduced stiffness relative to body size (body weight × bone length) was associated with odds ratios of 1.5 (95% confidence interval [CI], 0.5-4.3) and 7.0 (95% CI, 2.0-25.1) for women and men, respectively, for developing a stress fracture based on radiography and scintigraphy. K-means cluster analysis was used to segregate men and women into subgroups based on robustness, Ct.Ar, and TMD adjusted for body size. Stiffness varied 37% to 42% among the clusters (p < 0.0001, ANOVA). For men, 78% of stress fracture cases segregated to three clusters (p < 0.03, chi-square). Clusters showing reduced function exhibited either slender tibias with the expected Ct.Ar and TMD relative to body size and robustness (ie, well-adapted bones) or robust tibias with reduced residuals for Ct.Ar or TMD relative to body size and robustness (ie, poorly adapted bones). Thus, we show there are multiple biomechanical and thus biological pathways leading to reduced function and

  2. Facts about Upper and Lower Limb Reduction Defects

    MedlinePlus

    ... its normal size or is missing. What We Know About Upper and Lower Limb Reduction Defects How ... and productive lives. What We Still Do Not Know About Upper and Lower Limb Reduction Defects What ...

  3. Effect of axial tibial torque direction on ACL relative strain and strain rate in an in vitro simulated pivot landing.

    PubMed

    Oh, Youkeun K; Kreinbrink, Jennifer L; Wojtys, Edward M; Ashton-Miller, James A

    2012-04-01

    Anterior cruciate ligament (ACL) injuries most frequently occur under the large loads associated with a unipedal jump landing involving a cutting or pivoting maneuver. We tested the hypotheses that internal tibial torque would increase the anteromedial (AM) bundle ACL relative strain and strain rate more than would the corresponding external tibial torque under the large impulsive loads associated with such landing maneuvers. Twelve cadaveric female knees [mean (SD) age: 65.0 (10.5) years] were tested. Pretensioned quadriceps, hamstring, and gastrocnemius muscle-tendon unit forces maintained an initial knee flexion angle of 15°. A compound impulsive test load (compression, flexion moment, and internal or external tibial torque) was applied to the distal tibia while recording the 3D knee loads and tibofemoral kinematics. AM-ACL relative strain was measured using a 3 mm DVRT. In this repeated measures experiment, the Wilcoxon signed-rank test was used to test the null hypotheses with p < 0.05 considered significant. The mean (±SD) peak AM-ACL relative strains were 5.4 ± 3.7% and 3.1 ± 2.8% under internal and external tibial torque, respectively. The corresponding mean (± SD) peak AM-ACL strain rates reached 254.4 ± 160.1%/s and 179.4 ± 109.9%/s, respectively. The hypotheses were supported in that the normalized mean peak AM-ACL relative strain and strain rate were 70 and 42% greater under internal than under external tibial torque, respectively (p = 0.023, p = 0.041). We conclude that internal tibial torque is a potent stressor of the ACL because it induces a considerably (70%) larger peak strain in the AM-ACL than does a corresponding external tibial torque. Copyright © 2011 Orthopaedic Research Society.

  4. Ketorolac Administered in the Recovery Room for Acute Pain Management Does Not Affect Healing Rates of Femoral and Tibial Fractures.

    PubMed

    Donohue, David; Sanders, Drew; Serrano-Riera, Rafa; Jordan, Charles; Gaskins, Roger; Sanders, Roy; Sagi, H Claude

    2016-09-01

    To determine whether ketorolac administered in the immediate perioperative period affects the rate of nonunion in femoral and tibial shaft fractures. Retrospective comparative study. Single Institution, Academic Level 1 Trauma Center. Three hundred and thirteen skeletally mature patients with 137 femoral shaft (OTA 32) and 191 tibial shaft (OTA 42) fractures treated with intramedullary rod fixation. Eighty patients with 33 femoral shaft and 52 tibial shaft fractures were administered ketorolac within the first 24 hours after surgery (group 1-study group). Two-hundred thirty-three patients with 104 femoral shaft and 139 tibial shaft fractures were not (group 2-control group). Rate of reoperation for repair of a nonunion and time to union. Average time to union of the femur was 147 days for group 1 and 159 days for group 2 (P = 0.57). Average time to union of the tibia was 175 days for group 1 and 175 days for group 2 (P = 0.57). There were 3 femoral nonunions (9%) in group 1 and eleven femoral nonunions (11.6%) in group 2 (P = 1.00). There were 3 tibial nonunions (5.8%) in group 1 and 17 tibial nonunions (12.2%) in group 2 (P = 0.29). The average dose of ketorolac for patients who healed their fracture was 85 mg, whereas it was 50 mg for those who did not (P = 0.27). All patients with a nonunion in the study group were current smokers. Ketorolac administered in the first 24 hours after fracture repair for acute pain management does not seem to have a negative impact on time to healing or incidence of nonunion for femoral or tibial shaft fractures. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

  5. EFFECT OF AXIAL TIBIAL TORQUE DIRECTION ON ACL RELATIVE STRAIN AND STRAIN RATE IN AN IN VITRO SIMULATED PIVOT LANDING

    PubMed Central

    Oh, Youkeun K.; Kreinbrink, Jennifer L.; Wojtys, Edward M.; Ashton-Miller, James A.

    2011-01-01

    Anterior cruciate ligament (ACL) injuries most frequently occur under the large loads associated with a unipedal jump landing involving a cutting or pivoting maneuver. We tested the hypotheses that internal tibial torque would increase the anteromedial (AM) bundle ACL relative strain and strain rate more than would the corresponding external tibial torque under the large impulsive loads associated with such landing maneuvers. Twelve cadaveric female knees [mean (SD) age: 65.0 (10.5) years] were tested. Pretensioned quadriceps, hamstring and gastrocnemius muscle-tendon unit forces maintained an initial knee flexion angle of 15°. A compound impulsive test load (compression, flexion moment and internal or external tibial torque) was applied to the distal tibia while recording the 3-D knee loads and tibofemoral kinematics. AM-ACL relative strain was measured using a 3mm DVRT. In this repeated measures experiment, the Wilcoxon Signed-Rank test was used to test the null hypotheses with p<0.05 considered significant. The mean (± SD) peak AM-ACL relative strains were 5.4±3.7 % and 3.1±2.8 % under internal and external tibial torque, respectively. The corresponding mean (± SD) peak AM-ACL strain rates reached 254.4±160.1 %/sec and 179.4±109.9 %/sec, respectively. The hypotheses were supported in that the normalized mean peak AM-ACL relative strain and strain rate were 70% and 42% greater under internal than external tibial torque, respectively (p=0.023, p=0.041). We conclude that internal tibial torque is a potent stressor of the ACL because it induces a considerably (70%) larger peak strain in the AM-ACL than does a corresponding external tibial torque. PMID:22025178

  6. Minimally invasive treatment of tibial pilon fractures through arthroscopy and external fixator-assisted reduction.

    PubMed

    Luo, Huasong; Chen, Liaobin; Liu, Kebin; Peng, Songming; Zhang, Jien; Yi, Yang

    2016-01-01

    The aim of this study was to evaluate the clinical outcome of tibial pilon fractures treated with arthroscopy and assisted reduction with an external fixator. Thirteen patients with tibial pilon fractures underwent assisted reduction for limited lower internal fixation with an external fixator under arthroscopic guidance. The weight-bearing time was decided on the basis of repeat radiography of the tibia 3 months after surgery. Postoperative ankle function was evaluated according to the Mazur scoring system. Healing of fractures was achieved in all cases, with no complications such as severe infection, skin necrosis, or an exposed plate. There were 9 excellent, 2 good, and 2 poor outcomes, scored according to the Mazur system. The acceptance rate was 85%. Arthroscopy and external fixator-assisted reduction for the minimally invasive treatment of tibial pilon fractures not only produced less trauma but also protected the soft tissues and blood supply surrounding the fractures. External fixation could indirectly provide reduction and effective operative space for arthroscopic implantation, especially for AO type B fractures and partial AO type C1 fractures.

  7. Injectable Reactive Biocomposites For Bone Healing In Critical-Size Rabbit Calvarial Defects

    DTIC Science & Technology

    2012-03-29

    defects (i.e. be conformable), provide temporary protection to the brain until the bone heals, and enhance tissue regeneration with the delivery of...temporary protection to the brain until the bone heals, and enhance tissue regeneration with the delivery of biologics. In this study, we evaluated the...complex defects (i.e. be conformable), harden to provide temporary protection until tissue remodels (i.e. be settable), and enhance tissue regeneration

  8. Regional fibrocartilage variations in human anterior cruciate ligament tibial insertion: a histological three-dimensional reconstruction.

    PubMed

    Dai, Can; Guo, Lin; Yang, Liu; Wu, Yi; Gou, Jingyue; Li, Bangchun

    2015-02-01

    We studied anterior cruciate ligament (ACL) tibial insertion architecture in humans and investigated regional differences that could suggest unequal force transmission from ligament to bone. ACL tibial insertions were processed histologically. With Photoshop software, digital images taken from the histological slides were collaged, contour lines were drawn, and different gray values were filled based on the structure. The data were exported to Amira software for three-dimensional reconstruction. The uncalcified fibrocartilage (UF) layer was divided into three regions: lateral, medial and posterior according to the architecture. The UF zone was significantly thicker laterally than medially or posteriorly (p < 0.05). Similarly, the calcified fibrocartilage (CF) thickness was significantly greater in the lateral part of the enthesis compared to the medial and posterior parts (p < 0.05). The UF quantity (more UF laterally) corresponding to the CF quantity (more CF laterally) at the ACL tibial insertion provides further evidence suggesting that the load transferred from the ACL to the tibia was greater laterally than medially and posteriorly.

  9. Tibial dyschondroplasia associated proteomic changes in chicken growth plate cartilage

    USDA-ARS?s Scientific Manuscript database

    Tibial dyschondroplasia (TD) is a poultry leg problem that affects the proximal growth plate of tibia preventing its transition to bone. To understand the disease-induced proteomic changes we compared the protein extracts of cartilage from normal and TD- affected growth plates. TD was induced by fe...

  10. Bone repair of critical size defects treated with mussel powder associated or not with bovine bone graft: histologic and histomorphometric study in rat calvaria.

    PubMed

    Trotta, Daniel Rizzo; Gorny, Clayton; Zielak, João César; Gonzaga, Carla Castiglia; Giovanini, Allan Fernando; Deliberador, Tatiana Miranda

    2014-09-01

    The objective of this study was to evaluate the bone repair of critical size defects treated with mussel powder with or without additional bovine bone. Critical size defects of 5 mm were realized in the calvaria of 70 rats, which were randomly divided in 5 groups - Control (C), Autogenous Bone (AB), Mussel Powder (MP), Mussel Powder and Bovine Bone (MP-BB) and Bovine Bone (BB). Histological and histomorphometric analysis were performed 30 and 90 days after the surgical procedures (ANOVA e Tukey p < 0.05). After 30 days, the measures of remaining particles were: 28.36% (MP-BB), 26.63% (BB) and 8.64% (MP) with a statistically significant difference between BB and MP. The percentage of osseous matrix after 30 days was, AB (55.17%), 23.31% (BB), 11.66% (MP) and 10.71% (MP-BB) with statistically significant differences among all groups. After 90 days the figures were 25.05% (BB), 21.53% (MP-BB) and 1.97% (MP) with statistically significant differences between MP-BB and MP. Percentages of new bone formation after 90 days were 89.47% (AB), 35.70% (BB), 26.48% (MP-BB) and 7.37% (MP) with statistically significant differences between AB and the other groups. Within the limits of this study, we conclude that mussel powder, with or without additional bovine bone, did not induce new bone formation and did not repair critical size defects in rat calvaria. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  11. Probing defects in ZnO nanostructures by Photoluminescence and Positron Annihilation Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ghosh, Manoranjan; Raychaudhuri, A. K.; Chaudhuri, S. K.; Das, Dipankar

    2008-03-01

    We have investigated defect related emission in the blue green region (2.2 eV -- 2.5 eV) of ZnO nanostructures having spherical (5 nm-15 nm) as well as those with hexagonal platelet and rod like morphologies (20nm-100 nm), synthesized by solvo-thermal route. This emission show anomalous size dependence. Emission energy near 2.2 eV, shifts to higher energy (2.5 eV) for increase in size beyond 20nm when shape of the nanostructures changes. This change in photoluminescence has a close correlation with the size (and shape) induced change in the positron trapping rate which is directly proportional to the defect concentration. The trapping rates show non-monotonous dependence on size. It increases initially as the size increases (5nm-15nm) and then decreases as the size increases beyond 20nm. While increase of the trapping rate on size reduction is expected due to accumulation of more defects at the surface, the initial dependence of the trapping rate on the size (below 20nm) is anomalous. The data are explained by the presence of defects like Zn vacancy and confinement due to size reduction.

  12. Systemic Treatment with Strontium Ranelate Accelerates the Filling of a Bone Defect and Improves the Material Level Properties of the Healing Bone

    PubMed Central

    Zacchetti, Giovanna; Rizzoli, René

    2014-01-01

    Rapid bone defect filling with normal bone is a challenge in orthopaedics and dentistry. Strontium ranelate (SrRan) has been shown to in vitro decrease bone resorption and increase bone formation, and represents a potential agent with the capacity to accelerate bone defect filling. In this study, bone tibial defects of 2.5 mm in diameter were created in 6-month-old female rats orally fed SrRan (625 mg/kg/d; 5/7 days) or vehicle for 4, 8, or 12 weeks (10 rats per group per time point) from the time of surgery. Tibias were removed. Micro-architecture was determined by micro-computed tomography (µCT) and material level properties by nanoindentation analysis. µCT analysis showed that SrRan administration significantly improved microarchitecture of trabecular bone growing into the defect after 8 and 12 weeks of treatment compared to vehicle. SrRan treatment also accelerated the growth of cortical bone over the defect, but with different kinetics compared to trabecular bone, as the effects were already significant after 4 weeks. Nanoindentation analysis demonstrated that SrRan treatment significantly increased material level properties of both trabecular bone and cortical bone filling the defect compared to vehicle. SrRan accelerates the filling of bone defect by improving cortical and trabecular bone microarchitecture both quantitatively and qualitatively. PMID:25243150

  13. A new aiming guide can create the tibial tunnel at favorable position in transtibial pullout repair for the medial meniscus posterior root tear.

    PubMed

    Furumatsu, T; Kodama, Y; Fujii, M; Tanaka, T; Hino, T; Kamatsuki, Y; Yamada, K; Miyazawa, S; Ozaki, T

    2017-05-01

    Injuries to the medial meniscus (MM) posterior root lead to accelerated cartilage degeneration of the knee. An anatomic placement of the MM posterior root attachment is considered to be critical in transtibial pullout repair of the medial meniscus posterior root tear (MMPRT). However, tibial tunnel creation at the anatomic attachment of the MM posterior root is technically difficult using a conventional aiming device. The aim of this study was to compare two aiming guides. We hypothesized that a newly-developed guide, specifically designed, creates the tibial tunnel at an adequate position rather than a conventional device. Twenty-six patients underwent transtibial pullout repairs. Tibial tunnel creation was performed using the Multi-use guide (8 cases) or the PRT guide that had a narrow twisting/curving shape (18 cases). Three-dimensional computed tomography images of the tibial surface were evaluated using the Tsukada's measurement method postoperatively. Expected anatomic center of the MM posterior root attachment and tibial tunnel center were evaluated using the percentage-based posterolateral location on the tibial surface. Percentage distance between anatomic center and tunnel center was calculated. Anatomic center of the MM posterior root footprint located at a position of 78.5% posterior and 39.4% lateral. Both tunnels were anteromedial but tibial tunnel center located at a more favorable position in the PRT group: percentage distance was significantly smaller in the PRT guide group (8.7%) than in the Multi-use guide group (13.1%). The PRT guide may have great advantage to achieve a more anatomic location of the tibial tunnel in MMPRT pullout repair. III. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  14. Tibial Plateau Fractures in Elderly Patients

    PubMed Central

    Vemulapalli, Krishna C.; Gary, Joshua L.; Donegan, Derek J.

    2016-01-01

    Tibial plateau fractures are common in the elderly population following a low-energy mechanism. Initial evaluation includes an assessment of the soft tissues and surrounding ligaments. Most fractures involve articular depression leading to joint incongruity. Treatment of these fractures may be complicated by osteoporosis, osteoarthritis, and medical comorbidities. Optimal reconstruction should restore the mechanical axis, provide a stable construct for mobilization, and reestablish articular congruity. This is accomplished through a variety of internal or external fixation techniques or with acute arthroplasty. Regardless of the treatment modality, particular focus on preservation and maintenance of the soft tissue envelope is paramount. PMID:27551570

  15. External versus internal fixation for bicondylar tibial plateau fractures: systematic review and meta-analysis.

    PubMed

    Metcalfe, David; Hickson, Craig J; McKee, Lesley; Griffin, Xavier L

    2015-12-01

    It is uncertain whether external fixation or open reduction internal fixation (ORIF) is optimal for patients with bicondylar tibial plateau fractures. A systematic review using Ovid MEDLINE, Embase Classic, Embase, AMED, the Cochrane Library, Open Grey, Orthopaedic Proceedings, WHO International Clinical Trials Registry Platform, Current Controlled Trials, US National Institute for Health Trials Registry, and the Cochrane Central Register of Controlled Trials. The search was conducted on 3rd October 2014 and no language limits were applied. Inclusion criteria were all clinical study designs comparing external fixation with open reduction internal fixation of bicondylar tibial plateau fractures. Studies of only one treatment modality were excluded, as were those that included unicondylar tibial plateau fractures. Treatment effects from studies reporting dichotomous outcomes were summarised using odds ratios. Continuous outcomes were converted to standardized mean differences to assess the treatment effect, and inverse variance methods used to combine data. A fixed effect model was used for meta-analyses. Patients undergoing external fixation were more likely to have returned to preinjury activities by six and twelve months (P = 0.030) but not at 24 months follow-up. However, external fixation was complicated by a greater number of infections (OR 2.59, 95 % CI 1.25-5.36, P = 0.01). There were no statistically significant differences in the rates of deep infection, venous thromboembolism, compartment syndrome, or need for re-operation between the two groups. Although external fixation and ORIF are associated with different complication profiles, both are acceptable strategies for managing bicondylar tibial plateau fractures.

  16. Contact Kinematics Correlates to Tibial Component Migration Following Single Radius Posterior Stabilized Knee Replacement.

    PubMed

    Teeter, Matthew G; Perry, Kevin I; Yuan, Xunhua; Howard, James L; Lanting, Brent A

    2018-03-01

    Contact kinematics between total knee arthroplasty components is thought to affect implant migration; however, the interaction between kinematics and tibial component migration has not been thoroughly examined in a modern implant system. A total of 24 knees from 23 patients undergoing total knee arthroplasty with a single radius, posterior stabilized implant were examined. Patients underwent radiostereometric analysis at 2 and 6 weeks, 3 and 6 months, and 1 and 2 years to measure migration of the tibial component in all planes. At 1 year, patients also had standing radiostereometric analysis examinations acquired in 0°, 20°, 40°, and 60° of flexion, and the location of contact and magnitude of any condylar liftoff was measured for each flexion angle. Regression analysis was performed between kinematic variables and migration at 1 year. The average magnitude of maximum total point motion across all patients was 0.671 ± 0.270 mm at 1 year and 0.608 ± 0.359 mm at 2 years (P = .327). Four implants demonstrated continuous migration of >0.2 mm between the first and second year of implantation. There were correlations between the location of contact and tibial component anterior-posterior tilt, varus-valgus tilt, and anterior-posterior translation. The patients with continuous migration demonstrated atypical kinematics and condylar liftoff in some instances. Kinematics can influence tibial component migration, likely through alterations of force transmission. Abnormal kinematics may play a role in long-term implant loosening. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Tibial nerve stimulation for overactive bladder syndrome unresponsive to medical therapy.

    PubMed

    Ridout, A E; Yoong, W

    2010-02-01

    Overactive bladder syndrome is defined as a symptom syndrome which includes urinary urgency, with or without urge incontinence, usually accompanied by frequency (>8 micturitions/24 h) and nocturia. Conservative treatment usually comprises behavioural techniques, bladder retraining, pelvic floor re-education and pharmacotherapy but up to 30% of patients will remain refractory to treatment. Although second-line treatment options such as sacral nerve stimulation and intravesical botulinum A injections are valuable additions to the therapeutic arsenal, they are relatively invasive and can have serious side-effects. Inhibition of detrusor activity by peripheral neuromodulation of the posterior tibial nerve was first described in 1983, with recent authors further confirming a 60-80% positive response rate. This review was undertaken to examine published literature on percutaneous tibial nerve stimulation and to discuss outcome measures, maintenance therapy and prognostic factors of this technique.

  18. Increases in tibial force imbalance but not changes in tibiofemoral laxities are caused by varus-valgus malalignment of the femoral component in kinematically aligned TKA.

    PubMed

    Riley, Jeremy; Roth, Joshua D; Howell, Stephen M; Hull, Maury L

    2018-01-29

    The purposes of this study were to quantify the increase in tibial force imbalance (i.e. magnitude of difference between medial and lateral tibial forces) and changes in laxities caused by 2° and 4° of varus-valgus (V-V) malalignment of the femoral component in kinematically aligned total knee arthroplasty (TKA) and use the results to detemine sensitivities to errors in making the distal femoral resections. Because V-V malalignment would introduce the greatest changes in the alignment of the articular surfaces at 0° flexion, the hypotheses were that the greatest increases in tibial force imbalance would occur at 0° flexion, that primarily V-V laxity would significantly change at this flexion angle, and that the tibial force imbalance would increase and laxities would change in proportion to the degree of V-V malalignment. Kinematically aligned TKA was performed on ten human cadaveric knee specimens using disposable manual instruments without soft tissue release. One 3D-printed reference femoral component, with unmodified geometry, was aligned to restore the native distal and posterior femoral joint lines. Four 3D-printed femoral components, with modified geometry, introduced V-V malalignments of 2° and 4° from the reference component. Medial and lateral tibial forces were measured during passive knee flexion-extension between 0° to 120° using a custom tibial force sensor. Eight laxities were measured from 0° to 120° flexion using a six degree-of-freedom load application system. With the tibial component kinematically aligned, the increase in the tibial force imbalance from that of the reference component at 0° of flexion was sensitive to the degree of V-V malalignment of the femoral component. Sensitivities were 54 N/deg (medial tibial force increasing > lateral tibial force) (p < 0.0024) and 44 N/deg (lateral tibial force increasing > medial tibial force) (p < 0.0077) for varus and valgus malalignments, respectively. Varus

  19. Bone repair by cell-seeded 3D-bioplotted composite scaffolds made of collagen treated tricalciumphosphate or tricalciumphosphate-chitosan-collagen hydrogel or PLGA in ovine critical-sized calvarial defects.

    PubMed

    Haberstroh, Kathrin; Ritter, Kathrin; Kuschnierz, Jens; Bormann, Kai-Hendrik; Kaps, Christian; Carvalho, Carlos; Mülhaupt, Rolf; Sittinger, Michael; Gellrich, Nils-Claudius

    2010-05-01

    The aim of this study was to investigate the osteogenic effect of three different cell-seeded 3D-bioplotted scaffolds in a ovine calvarial critical-size defect model. The choice of scaffold-materials was based on their applicability for 3D-bioplotting and respective possibility to produce tailor-made scaffolds for the use in cranio-facial surgery for the replacement of complex shaped boneparts. Scaffold raw-materials are known to be osteoinductive when being cell-seeded [poly(L-lactide-co-glycolide) (PLGA)] or having components with osteoinductive properties as tricalciumphosphate (TCP) or collagen (Col) or chitosan. The scaffold-materials PLGA, TCP/Col, and HYDR (TCP/Col/chitosan) were cell-seeded with osteoblast-like cells whether gained from bone (OLB) or from periost (OLP). In a prospective and randomized design nine sheep underwent osteotomy to create four critical-sized calvarial defects. Three animals each were assigned to the HYDR-, the TCP/Col-, or the PLGA-group. In each animal, one defect was treated with a cell-free, an OLB- or OLP-seeded group-specific scaffold, respectively. The fourth defect remained untreated as control (UD). Fourteen weeks later, animals were euthanized for histo-morphometrical analysis of the defect healing. OLB- and OLP-seeded HYDR and OLB-seeded TCP/Col scaffolds significantly increased the amount of newly formed bone (NFB) at the defect bottom and OLP-seeded HYDR also within the scaffold area, whereas PLGA-scaffolds showed lower rates. The relative density of NFB was markedly higher in the HYDR/OLB group compared to the corresponding PLGA group. TCP/Col had good stiffness to prepare complex structures by bioplotting but HYDR and PLGA were very soft. HYDR showed appropriate biodegradation, TCP/Col and PLGA seemed to be nearly undegraded after 14 weeks. 3D-bioplotted, cell-seeded HYDR and TCP/Col scaffolds increased the amount of NFB within ovine critical-size calvarial defects, but stiffness, respectively, biodegradation of

  20. Risk of total knee arthroplasty after operatively treated tibial plateau fracture: a matched-population-based cohort study.

    PubMed

    Wasserstein, David; Henry, Patrick; Paterson, J Michael; Kreder, Hans J; Jenkinson, Richard

    2014-01-15

    The aims of operative treatment of displaced tibial plateau fractures are to stabilize the injured knee to restore optimal function and to minimize the risk of posttraumatic arthritis and the eventual need for total knee arthroplasty. The purpose of our study was to define the rate of subsequent total knee arthroplasty after tibial plateau fractures in a large cohort and to compare that rate with the rate in the general population. All patients sixteen years of age or older who had undergone surgical treatment of a tibial plateau fracture from 1996 to 2009 in the province of Ontario, Canada, were identified from administrative health databases with use of surgeon fee codes. Each member of the tibial plateau fracture cohort was matched to four individuals from the general population according to age, sex, income, and urban/rural residence. The rates of total knee arthroplasty at two, five, and ten years were compared by using time-to-event analysis. A separate Cox proportional hazards model was used to explore the influence of patient, provider, and surgical factors on the time to total knee arthroplasty. We identified 8426 patients (48.5% female; median age, 48.9 years) who had undergone fixation of a tibial plateau fracture and matched them to 33,698 controls. The two, five, and ten-year rates of total knee arthroplasty in the plateau fracture and control cohorts were 0.32% versus 0.29%, 5.3% versus 0.82%, and 7.3% versus 1.8%, respectively (p < 0.0001). After adjustment for comorbidity, plateau fracture surgery was found to significantly increase the likelihood of total knee arthroplasty (hazard ratio [HR], 5.29 [95% confidence interval, 4.58, 6.11]; p < 0.0001). Higher rates of total knee arthroplasty were also associated with increasing age (HR, 1.03 [1.03, 1.04] per year over the age of forty-eight; p < 0.0001), bicondylar fracture (HR, 1.53 [1.26, 1.84]; p < 0.0001), and greater comorbidity (HR, 2.17 [1.70, 2.77]; p < 0.001). Ten years after tibial plateau

  1. Internal-external malalignment of the femoral component in kinematically aligned total knee arthroplasty increases tibial force imbalance but does not change laxities of the tibiofemoral joint.

    PubMed

    Riley, Jeremy; Roth, Joshua D; Howell, Stephen M; Hull, Maury L

    2018-06-01

    The purposes of this study were to quantify the increase in tibial force imbalance (i.e. magnitude of difference between medial and lateral tibial forces) and changes in laxities caused by  2° and 4° of internal-external (I-E) malalignment of the femoral component in kinematically aligned total knee arthroplasty. Because I-E malalignment would introduce the greatest changes to the articular surfaces near 90° of flexion, the hypotheses were that the tibial force imbalance would be significantly increased near 90° flexion and that primarily varus-valgus laxity would be affected near 90° flexion. Kinematically aligned TKA was performed on ten human cadaveric knee specimens using disposable manual instruments without soft tissue release. One 3D-printed reference femoral component, with unmodified geometry, was aligned to restore the native distal and posterior femoral joint lines. Four 3D-printed femoral components, with modified geometry, introduced I-E malalignments of 2° and 4° from the reference component. Medial and lateral tibial forces were measured from 0° to 120° flexion using a custom tibial force sensor. Bidirectional laxities in four degrees of freedom were measured from 0° to 120° flexion using a custom load application system. Tibial force imbalance increased the greatest at 60° flexion where a regression analysis against the degree of I-E malalignment yielded sensitivities (i.e. slopes) of 30 N/° (medial tibial force > lateral tibial force) and 10 N/° (lateral tibial force > medial tibial force) for internal and external malalignments, respectively. Valgus laxity increased significantly with the 4° external component with the greatest increase of 1.5° occurring at 90° flexion (p < 0.0001). With the tibial component correctly aligned, I-E malalignment of the femoral component caused significant increases in tibial force imbalance. Minimizing I-E malalignment lowers the increase in the tibial force imbalance. By keeping

  2. High-throughput automatic defect review for 300mm blank wafers with atomic force microscope

    NASA Astrophysics Data System (ADS)

    Zandiatashbar, Ardavan; Kim, Byong; Yoo, Young-kook; Lee, Keibock; Jo, Ahjin; Lee, Ju Suk; Cho, Sang-Joon; Park, Sang-il

    2015-03-01

    While feature size in lithography process continuously becomes smaller, defect sizes on blank wafers become more comparable to device sizes. Defects with nm-scale characteristic size could be misclassified by automated optical inspection (AOI) and require post-processing for proper classification. Atomic force microscope (AFM) is known to provide high lateral and the highest vertical resolution by mechanical probing among all techniques. However, its low throughput and tip life in addition to the laborious efforts for finding the defects have been the major limitations of this technique. In this paper we introduce automatic defect review (ADR) AFM as a post-inspection metrology tool for defect study and classification for 300 mm blank wafers and to overcome the limitations stated above. The ADR AFM provides high throughput, high resolution, and non-destructive means for obtaining 3D information for nm-scale defect review and classification.

  3. Tibial plateau fracture after anterior cruciate ligament reconstruction: Role of the interference screw resorption in the stress riser effect.

    PubMed

    Thaunat, Mathieu; Nourissat, Geoffroy; Gaudin, Pascal; Beaufils, Philippe

    2006-06-01

    We report a case of tibial plateau fracture after previous anterior cruciate ligament (ACL) reconstruction using patellar tendon autograft and bioabsorbable screws 4 years previously. The fracture occurred through the tibial tunnel. The interference screw had undergone complete resorption and the tunnel widening had increased. The resorption of the interference screw did not simultaneously promote and foster the growth of surrounding bone tissue. Therefore, the area of reactive tissue left by the screw resorption in an enlarged bone tunnel may lead to vulnerability of the tibial plateau. Stress risers would occur following ACL reconstruction if either resorption is not complete or bony integration is not complete.

  4. Symptomatic venous thromboembolism following circular frame treatment for tibial fractures.

    PubMed

    Vollans, S; Chaturvedi, A; Sivasankaran, K; Madhu, T; Hadland, Y; Allgar, V; Sharma, H K

    2015-01-01

    Venous thromboembolism (VTE) is a significant cause of morbidity and mortality following tibial fractures. The risk is as high as 77% without prophylaxis and around 10% with prophylaxis. Within the current literature there are no figures reported specifically for those individuals treated with circular frames. Our aim was to evaluate the VTE incidence within a single surgeon series and to evaluate potential risk factors. We retrospectively reviewed our consecutive single surgeon series of 177 patients admitted to a major trauma unit with tibial fractures. All patients received standardised care, including chemical thromboprophylaxis within 24h of injury until independent mobility was achieved. We comprehensively reviewed our prospective database and medical records looking at demographics and potential risk factors. Seven patients (4.0% ± 2.87%) developed symptomatic VTE during the course of frame treatment; three deep vein thrombosis (DVTs) and four pulmonary embolisms (PEs). Those with a VTE event had significantly increased body mass index (BMI) (p = 0.01) when compared to those without symptomatic VTE. No differences (p > 0.05) were observed between the groups in age, gender, smoking status, fracture type (anatomical allocation or open/closed), delay to frame treatment, weight bearing status post-frame, inpatient stay or total duration of frame treatment. This study suggests that increased BMI is a statistically significant risk factor for VTE, as reported in current literature. In addition, we calculated the true risk of VTE following circular frame treatment for tibial fracture in our series is from 1.13% to 6.87%, which is at least comparable to other forms of treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Heat-Treatment of Defective UiO-66 from Modulated Synthesis: Adsorption and Stability Studies

    DOE PAGES

    Jiao, Yang; Liu, Yang; Zhu, Guanghui; ...

    2017-09-21

    Defect engineering in metal–organic frameworks (MOFs) is an emerging strategy that can be used to control physical or chemical characteristics of MOFs, including adsorption behavior and textural, mechanical, and conductive properties. Understanding the impact of defects on textural properties and chemical stability of MOFs is imperative to the development of MOFs with tunable defect sites. In this work, systematic adsorption measurements were performed with three adsorbate molecules (SO 2, benzene, and cyclohexane) to investigate changes in the pore size of defective UiO-66. Compared to the parent UiO-66, the defective UiO-66 shows significant changes in adsorption capacities among the selected adsorbatemore » molecules, demonstrating that pore size is significantly enlarged by the missing cluster defects. BET surface area analysis and DFT calculations were also performed to interrogate the chemical stability of the defective MOFs after exposure to water and acidic environments. This work shows that pore size can be tuned as a function of defect concentration. Further, it is shown that the structural incorporation of trifluoroacetate groups in defective UiO-66 leads to an increase in average pore size without sacrificing chemical stability toward water and acidic species. The results of this work advance the understanding of textural properties and chemical stability of defect-engineered MOFs and also suggest a preparation method for synthesizing defective but stable MOFs.« less

  6. Technique tip: use of anterior cruciate ligament jig for hindfoot fusion by calcanio-talo-tibial nail.

    PubMed

    Haque, Syed; Sarkar, Jay

    2012-08-01

    The use of intramedullary nail fixation for tibio-talo-calcaneal fusion is gaining popularity. There is chance of failure of procedure following faulty operative technique specially alignment. The article describes a useful application of tibial tunnel jig in inserting the calcanio-talo-tibial guide wire. There is precision of few millimeters in the exit point of guide wire on talus. The authors believe that this helps in better positioning of nail and hence better alignment and better operative outcome.

  7. Popliteal versus tibial retrograde access for subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) technique.

    PubMed

    Hua, W R; Yi, M Q; Min, T L; Feng, S N; Xuan, L Z; Xing, J

    2013-08-01

    This study aimed to ascertain differences in benefit and effectiveness of popliteal versus tibial retrograde access in subintimal arterial flossing with the antegrade-retrograde intervention (SAFARI) technique. This was a retrospective study of SAFARI-assisted stenting for long chronic total occlusion (CTO) of TASC C and D superficial femoral lesions. 38 cases had superficial femoral artery lesions (23 TASC C and 15 TASC D). All 38 cases underwent SAFARI-assisted stenting. The ipsilateral popliteal artery was retrogradely punctured in 17 patients. A distal posterior tibial (PT) or dorsalis pedis (DP) artery was retrogradely punctured in 21 patients, and 16 of them were punctured after open surgical exposure. SAFARI technical success was achieved in all cases. There was no significant difference in 1-year primary patency (75% vs. 78.9%, p = .86), secondary patency (81.2% vs. 84.2%, p = .91) and access complications (p = 1.00) between popliteal and tibial retrograde access. There was statistical difference in operation time between popliteal (140.1 ± 28.4 min) and tibial retrograde access with PT/DP punctures after surgical vessel exposure (120.4 ± 23.0 min, p = .04). The SAFARI technique is a safe and feasible option for patients with infrainguinal CTO (TASC II C and D). The PT or DP as the retrograde access after surgical vessel exposure is a good choice when using the SAFARI technique. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  8. Opening-wedge high tibial osteotomy with a locked low-profile plate: surgical technique.

    PubMed

    Kolb, Werner; Guhlmann, Hanno; Windisch, Christoph; Koller, Heiko; Grützner, Paul; Kolb, Klaus

    2010-09-01

    High tibial osteotomy has been recognized as a beneficial treatment for osteoarthritis of the medial compartment of the knee. The purpose of this prospective study was to assess the short-term results of opening-wedge high tibial osteotomies with locked plate fixation. From September 2002 to November 2005, fifty-one consecutive medial opening-wedge high tibial osteotomies were performed. The mean age of the patients at the time of the index operation was forty-nine years. The preoperative and postoperative factors analyzed included the grade of arthritis of the tibiofemoral compartment (the Ahlbäck radiographic grade), the anatomic tibiofemoral angle, patellar height, the Hospital for Special Surgery rating system score, and the Lysholm and Gillquist knee score. Postoperatively, one superficial wound infection occurred. Fifty of the fifty-one osteotomies healed after an average period of 12.9 weeks (range, eight to sixteen weeks) without bone grafts. A nonunion developed in a sixty-two-year-old patient who was a cigarette smoker. The average postoperative tibiofemoral angle was 9° of valgus. Forty-nine patients were followed for a mean of fifty-two months. The average score on the Hospital for Special Surgery rating system was 86 points at the time of the most recent follow-up. The rating was excellent in twenty-eight patients (57%), good in twelve (24%), fair in four (8%), and poor in five (10%). The average score on the Lysholm and Gillquist knee-scoring scale was 83 points. According to these scores, the outcome was excellent in nine patients (18%), good in thirty-one (63%), fair in three (6%), and poor in six (12%). Four knees failed after an average of thirty-six months. Our results suggest that an opening-wedge high tibial osteotomy with locked plate fixation allows a correct valgus angle to be achieved with good short-term results.

  9. Evaluation of cranial tibial and extensor carpi radialis reflexes before and after anesthetic block in cats.

    PubMed

    Tudury, Eduardo Alberto; de Figueiredo, Marcella Luiz; Fernandes, Thaiza Helena Tavares; Araújo, Bruno Martins; Bonelli, Marília de Albuquerque; Diogo, Camila Cardoso; Silva, Amanda Camilo; Santos, Cássia Regina Oliveira; Rocha, Nadyne Lorrayne Farias Cardoso

    2017-02-01

    Objectives This study aimed to test the extensor carpi radialis and cranial tibial reflexes in cats before and after anesthetic block of the brachial and lumbosacral plexus, respectively, to determine whether they depend on a myotatic reflex arc. Methods Fifty-five cats with a normal neurologic examination that were referred for elective gonadectomy were divided into group 1 (29 cats) for testing the extensor carpi radialis reflex, and group 2 (26 cats) for testing the cranial tibial reflex. In group 1, the extensor carpi radialis reflex was tested after anesthetic induction and 15 mins after brachial plexus block with lidocaine. In group 2, the cranial tibial, withdrawal and patellar reflexes were elicited in 52 hindlimbs and retested 15 mins after epidural anesthesia. Results In group 1, before the anesthetic block, 55.17% of the cats had a decreased and 44.83% had a normal extensor carpi radialis reflex. After the block, 68.96% showed a decreased and 27.59% a normal reflex. No cat had an increased or absent reflex before anesthetic block. In group 2, prior to the anesthetic block, 15.38% of the cats had a decreased cranial tibial reflex and 84.62% had a normal response, whereas after the block it was decreased in 26.92% and normal in 73.08% of the cats. None of the cats had an increased or absent reflex. Regarding the presence of both reflexes before and after anesthetic block, there was no significant difference at 1% ( P = 0.013). Conclusions and relevance The extensor carpi radialis and cranial tibial reflexes in cats are not strictly myotatic reflexes, as they are independent of the reflex arc, and may be idiomuscular responses. Therefore, they are not reliable for neurologic examination in this species.

  10. Landing strategies focusing on the control of tibial rotation in the initial contact period of one-leg forward hops.

    PubMed

    Chen, W-L; Chen, Y-T; Huang, S-Y; Yang, C-Y; Wu, C-D; Chang, C-W

    2017-08-01

    Anterior cruciate ligament (ACL) reconstruction (ACLR) surgeries successfully restore anterior tibial translation but not tibial rotation. This study aimed to explore landing strategies focusing on the control of tibial rotation at landing when the ACL is most vulnerable. Three groups of male subjects (50 ACLRs, 26 basketball players, and 31 controls) participated in one-leg forward hop tests for determining the tibial rotatory landing strategies adopted during the initial landing phase. The differences in knee kinematics and muscle activities between internal and external tibial rotatory (ITR, ETR) landing strategies were examined. A higher proportion of basketball players (34.6%) were found to adopt ITR strategies (controls: 6.5%), exhibiting significantly greater hopping distance and knee strength. After adjusting for hopping distance, subjects adopting ITR strategies were found to hop faster with straighter knees at foot contact and with greater ITR and less knee adduction angular displacement during the initial landing phase. However, significantly greater angular displacement in knee flexion, greater medial hamstring activities, and greater co-contraction index of hamstrings and medial knee muscles were also found during initial landing. Our results support the importance of the recruitments of medial hamstrings or the local co-contraction in assisting the rotatory control of the knee during initial landing for avoiding ACL injuries. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Trampoline fracture of the proximal tibial metaphysis in children may not progress into valgus: a report of seven cases and a brief review.

    PubMed

    Kakel, R

    2012-06-01

    Fracture of the proximal tibial metaphysis in children is a rare injury but notorious for carrying the risk of subsequent valgus deformity of the tibia. Trampoline-caused fracture of the proximal tibial metaphysis in children may not progress into valgus. We followed up six children who collectively sustained seven fractures of the proximal tibial metaphysis while trampolining with other heavier and/or older children. Initial and follow-up x-rays were reviewed by an orthopaedic surgeons and two radiologists. None of the patients developed valgus deformity with follow-up. Trampoline is associated with a specific type of injury to the proximal tibia when children are trampolining with other heavier children even without falling off the trampoline. This fracture is linear and complete, often non-displaced. Unlike "other" proximal tibial metaphyseal fractures, trampoline-associated proximal tibial metaphysical fracture in children is not associated with a risk of subsequent valgus deformity. Level 4. case series. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  12. Anatomy, function, and pathophysiology of the posterior tibial tendon.

    PubMed

    Smith, C F

    1999-07-01

    The posterior tibial tendon is vital for the structure and function of the foot and ankle. Dysfunction of the tendon can be debilitating and devastating. In recent years, much attention had been directed toward the diagnosis and treatment of PTTD. To properly diagnose and devise an appropriate treatment regimen, the anatomy, function, and pathophysiology associated with PTTD need to be thoroughly understood.

  13. Micro-bridge defects: characterization and root cause analysis

    NASA Astrophysics Data System (ADS)

    Santoro, Gaetano; Van den Heuvel, Dieter; Braggin, Jennifer; Rosslee, Craig; Leray, Philippe J.; Cheng, Shaunee; Jehoul, Christiane; Schreutelkamp, Robert; Hillel, Noam

    2010-03-01

    Defect review of advanced lithography processes is becoming more and more challenging as feature sizes decrease. Previous studies using a defect review SEM on immersion lithography generated wafers have resulted in a defect classification scheme which, among others, includes a category for micro-bridges. Micro-bridges are small connections between two adjacent lines in photo-resist and are considered device killing defects. Micro-bridge rates also tend to increase as feature sizes decrease, making them even more important for the next technology nodes. Especially because micro-bridge defects can originate from different root causes, the need to further refine and split up the classification of this type of defect into sub groups may become a necessity. This paper focuses on finding the correlation of the different types of micro-bridge defects to a particular root cause based on a full characterization and root cause analysis of this class of defects, by using advanced SEM review capabilities like high quality imaging in very low FOV, Multi Perspective SEM Imaging (MPSI), tilted column and rotated stage (Tilt&Rotation) imaging and Focused Ion Beam (FIB) cross sectioning. Immersion lithography material has been mainly used to generate the set of data presented in this work even though, in the last part of the results, some EUV lithography data will be presented as part of the continuing effort to extend the micro-bridge defect characterization to the EUV technology on 40 nm technology node and beyond.

  14. Leg Muscle Usage on Tibial Elasticity During Running

    DTIC Science & Technology

    2005-01-01

    relative risk of forefoot versus heel- strike running. In summary, there is no evidence in the literature that either study arm is at more risk than...tested in TSF, or even studied in runners. These basic validation studies will determine if modulators of tibial stress, .such as heel- strike mechanics...the other for acute injuries, although it was agreed that forefoot runners will be periodically evaluated for injuries to the Achilles tendon. After

  15. Multiple Tibial Insufficiency Fractures in the Same Tibia

    PubMed Central

    Defoort, Saartje; Mertens, Peter

    2011-01-01

    Stress fractures were first described by Briethaupt in 1855. Since then, there have been many discussions in the literature concerning stress fractures, which have been described in both weight-bearing and non-weight-bearing bones. Currently, the tibia is the most frequent location, but multiple stress fractures in the same tibia are rare. This paper presents an unusual case of a 60-year-old woman with multiple tibial stress fractures of spontaneous onset. PMID:23569673

  16. Recipe creation for automated defect classification with a 450mm surface scanning inspection system based on the bidirectional reflectance distribution function of native defects

    NASA Astrophysics Data System (ADS)

    Yathapu, Nithin; McGarvey, Steve; Brown, Justin; Zhivotovsky, Alexander

    2016-03-01

    This study explores the feasibility of Automated Defect Classification (ADC) with a Surface Scanning Inspection System (SSIS). The defect classification was based upon scattering sensitivity sizing curves created via modeling of the Bidirectional Reflectance Distribution Function (BRDF). The BRDF allowed for the creation of SSIS sensitivity/sizing curves based upon the optical properties of both the filmed wafer samples and the optical architecture of the SSIS. The elimination of Polystyrene Latex Sphere (PSL) and Silica deposition on both filmed and bare Silicon wafers prior to SSIS recipe creation and ADC creates a challenge for light scattering surface intensity based defect binning. This study explored the theoretical maximal SSIS sensitivity based on native defect recipe creation in conjunction with the maximal sensitivity derived from BRDF modeling recipe creation. Single film and film stack wafers were inspected with recipes based upon BRDF modeling. Following SSIS recipe creation, initially targeting maximal sensitivity, selected recipes were optimized to classify defects commonly found on non-patterned wafers. The results were utilized to determine the ADC binning accuracy of the native defects and evaluate the SSIS recipe creation methodology. A statistically valid sample of defects from the final inspection results of each SSIS recipe and filmed substrate were reviewed post SSIS ADC processing on a Defect Review Scanning Electron Microscope (SEM). Native defect images were collected from each statistically valid defect bin category/size for SEM Review. The data collected from the Defect Review SEM was utilized to determine the statistical purity and accuracy of each SSIS defect classification bin. This paper explores both, commercial and technical, considerations of the elimination of PSL and Silica deposition as a precursor to SSIS recipe creation targeted towards ADC. Successful integration of SSIS ADC in conjunction with recipes created via BRDF

  17. External fixation combined with delayed internal fixation in treatment of tibial plateau fractures with dislocation.

    PubMed

    Tao, Xingguang; Chen, Nong; Pan, Fugen; Cheng, Biao

    2017-10-01

    The aim of this study was to evaluate the clinical efficacy of external fixation, delayed open reduction, and internal fixation in treating tibial plateau fracture with dislocation.Clinical data of 34 patients diagnosed with tibial plateau fracture complicated with dislocation between January 2009 and May 2015 were retrospectively analyzed. Fifteen patients in group A underwent early calcaneus traction combined with open reduction and internal fixation and 19 in group B received early external fixation combined with delayed open reduction and internal fixation. Operation time, postoperative complication, bone healing time, knee joint range of motion, initial weight-bearing time, Rasmussen tibial plateau score, and knee function score (HSS) were statistically compared between 2 groups.The mean follow-up time was 18.6 months (range: 5-24 months). The mean operation time in group A was 96 minutes, significantly longer than 71 minutes in group B (P < .05). In group A, 5 cases had postoperative complications and 1 in group B (P < .05). The mean bone healing time in group A was 6.9 months (range: 5-9 months) and 6.0 months (range: 5-8 months) in group B (P > .05). In group A, initial weight-bearing time in group A was (14.0 ± 3.6) weeks, significantly differing from (12.9 ± 2.8) weeks in group B (P < 0.05). In group A, the mean knee joint range of motion was 122° (range: 95°-150°) and 135° (range: 100°-160°) in group B (P > 0.05). Rasmussen tibial plateau score in group A was slightly lower than that in group B (P > .05). The excellent rate of knee joint function in group A was 80% and 84.21% in group B (P > .05).External fixation combined with delayed open reduction and internal fixation is a safer and more efficacious therapy of tibial plateau fracture complicated with dislocation compared with early calcaneus traction and open reduction and internal fixation.

  18. Bone generation in the reconstruction of a critical size calvarial defect in an experimental model.

    PubMed

    Por, Yong-Chen; Barceló, C Raul; Salyer, Kenneth E; Genecov, David G; Troxel, Karen; Gendler, El; Elsalanty, Mohammed E; Opperman, Lynne A

    2008-03-01

    This study was designed to investigate the optimal combination of known osteogenic biomaterials with shape conforming struts to achieve calvarial vault reconstruction, using a canine model. Eighteen adolescent beagles were divided equally into 6 groups. A critical-size defect of 6 x 2 cm traversed the sagittal suture. The biomaterials used for calvarial reconstruction were demineralized perforated bone matrix (DBM), recombinant human bone morphogenetic protein 2 (rhBMP2), and autogenous platelet-rich plasma (PRP). The struts used were cobalt chrome (metal) or resorbable plate. The groupings were as follows: 1) DBM + metal, 2) DBM + PRP + metal, 3) DBM + PRP + resorbable plate, 4) DBM + rhBMP2 + metal, 5) DBM + rhBMP2 + PRP + metal, and 6) DBM + rhBMP2 + resorbable plate. Animals were killed at 3 months after surgery. There was no mortality or major complications. Analysis was performed macroscopically and histologically and with computed tomography. There was complete bony regeneration in the rhBMP2 groups only. Non-rhBMP2 groups had minimal bony ingrowth from the defect edges and on the dural surface, a finding confirmed by computed tomographic scan and histology. Platelet-rich plasma did not enhance bone regeneration. Shape conformation was good with both metal and resorbable plate. rhBMP2, but not PRP, accelerated calvarial regeneration in 3 months. The DBMs in the rhBMP2 groups were substituted by new trabecular bone. Shape molding was good with both metal and resorbable plate.

  19. Defect Characteristics of Reverse Hill-Sachs Lesions.

    PubMed

    Moroder, Philipp; Tauber, Mark; Scheibel, Markus; Habermeyer, Peter; Imhoff, Andreas B; Liem, Dennis; Lill, Helmut; Buchmann, Stefan; Wolke, Julia; Guevara-Alvarez, Alberto; Salmoukas, Katharina; Resch, Herbert

    2016-03-01

    Little scientific evidence regarding reverse Hill-Sachs lesions (RHSLs) in posterior shoulder instability exists. Recently, standardized measurement methods of the size and localization were introduced, and the biomechanical effect of the extent and position of the defects on the risk of re-engagement was determined. To analyze the characteristics and patterns of RHSLs in a large case series using standardized measurements and to interpret the results based on the newly available biomechanical findings. Case series; Level of evidence, 4. In this multicenter study, 102 cases of RHSLs in 99 patients were collected from 7 different shoulder centers between 2004 and 2013. Patient- as well as injury-specific information was gathered, and defect characteristics in terms of the size, localization, and depth index were determined on computed tomography or magnetic resonance imaging scans by means of standardized measurements. Additionally, the position (gamma angle) of the posterior defect margin as a predictor of re-engagement was analyzed. Three types of an RHSL were distinguished based on the pathogenesis and chronicity of the lesion: dislocation (D), locked dislocation (LD), and chronic locked dislocation (CLD). While the localization of the defects did not vary significantly between the subgroups (P = .072), their mean size differed signficantly (D: 32.6° ± 11.7°, LD: 49.4° ± 17.2°, CLD: 64.1° ± 20.7°; P < .001). The mean gamma angle as a predictor of re-engagement was similarly significantly different between groups (D: 83.8° ± 14.5°, LD: 96.5° ± 17.9°, CLD: 108.7° ± 18.4°; P < .001). The orientation of the posterior defect margin was consistently quite parallel to the humeral shaft axis, with a mean difference of 0.3° ± 8.1°. The distinction between the 3 different RHSL types based on the pathogenesis and chronicity of the defect helps identify defects prone to re-engagement. The gamma angle as a measurement of the position of the posterior

  20. Relationship between the tibial mechanical axis and bony anatomical landmarks of the calf and foot as measured on radiographs obtained with a new laser-calibrated position.

    PubMed

    He, Peiheng; Zhu, Qi; Zhang, Zhaohui; Zou, Xuenong; Xu, Dongliang

    2013-01-01

    To investigate relationship between the tibial mechanical axis and bony landmarks of the calf and foot by developing a new laser-calibrated position for radiography of the lower limb. A total of 120 volunteers were randomly divided into two groups. All subjects were marked with skin projection of the hypothetical axis of the calf on the frontal and sagittal planes. Radiographs of weight-bearing full-length lower-limb were obtained by the laser-calibrated positioning in the experimental group, and by the use of conventional technique in the control group. To consider the rotation of the calf, radiological features of the knee and ankle were investigated. The relationship between the tibial mechanical axis and the bony landmarks of the calf and foot were also measured. Anteroposterior view depicted a tangential projection on the superior/inferior tibiofibular syndesmosis and between lateral malleolus and talus in ankle mortise in the experimental group. Bony overlap on the superior/inferior tibiofibular syndesmosis and between lateral malleolus and talus was seen in control group. On the tangential projection, it also presented a clear wheel-like contour of the medial femoral condyle, but a partial overlap between medial femoral condyle and tibial plateau. The femoral joint angle between the connecting line at the lowest point of the medial and lateral femoral condyles and the tibial mechanical axis was 83.6° ± 2.49° in the experimental group and 85.3° ± 2.18° in the control group (P < 0.001). The tibial tubercle-axis distance from the center of the medial and middle one-third of the tibial tubercle to the tibial mechanical axis was 1.5 mm in the experimental group and 3.7 mm in the control group (P < 0.05). The malleoli-axis distance from the midpoint of the bimalleolar line joining the tips of the medial and lateral malleoli to the tibial mechanical axis was 1.9 mm in the experimental group and 6.9 mm in the control group (P < 0.001). Lateral view showed no