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Objective To study surgical therapy of the serious medial collateral ligament ruptures of the knee. Methods 12 patients with acute medial collateral ligament ruptures were treated operatively.Their degrees of injury were all Ⅲdegree that superficial and deep collateral ligaments were completely ruptured.Some of them were accompanied with the injury of medial joint capsule ligament or anterior cruciate ligament or posterior cruciate ligament.The torn medial collateral ligaments were anatomically corrected by their ends with direct suture or staple internal fixation.They were followed 6 to 18 months. Results 12 patients were graded with the Lysholm score .The postoperative score (mean, 76; range, 59 to 90) was higher compared with the preoperative score (mean, 35; range, 20 to 54), P
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Objective To introduce and evaluate the surgical reconstrutive technique for acetabular wear after artificial femoral head replacement. Methods Sixty patients with 60 painful hips after artificial femoral head replacements undergone revision hip arthroplasty were analysed.The most essential problem causing hip pain was mechanical wear in acetabulum(71％ ).The acetabular wear could be divided into 0－Ⅲ degrees,which could be reconstructed with regular acetabular preparation, impact of morselized bone graft and structural bone graft. The mean follow up period was 4.1 years (ranged from 12 months to 11 years). Results Based on Merle D'Aubigne evalvation system,50 patients (83％ ) had excellent results, 8 patients good or fair,1 case needed re- revision for septic hip, the other 2 hips had radiolucent lines around acetabular cup, but no clinical loosening. Conclusion The classification of acetabular wear allowed determinant of a certain option about soft tissue release,greater trochanter osteotomy or reconstruction of acetabulum during revision surgery. Impaction of morselized bone graft in reconstruction of acetabulum represented an attractive revision option. It also suggests that total hip arthroplasty or bipolar prosthesis may be superior to femoral head replacement for patients with femoral neck fracture.
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Objective: To synthesize the collagen-GAG template and to evaluate its feasibility to be used as the MSCs vehicle for meniscal tissue engineering. Methods: The collagen-GAG template was synthesized from rat tail type Ⅰ collagen and GAG using Yannas method. Then the post-stimulated MSCs by bFGF and TGF-β1 were added in. The MSCs-enriched collagen sponges were cultured in vitro， two weeks later the histological and ultrastructure detection was performed. Results: The histological and ultrastructure of the collagen-GAG template remained intact after 2 weeks' culture, and the MSCs in it remained viable. Conclusion: The collagen-GAG template synthesized in this experiment is suitable for the meniscal tissue engineering reconstruction as the vehicle for MSCs seed cells.
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Objective This is a feasibility study of rabbit meniscus regeneration evaluated with the use of autologous bone marrow derived mesenchymal stem cells(MSCs) and collagen glycosaminoglycan(GAG). Methods Autologous MSCs were prepared from the rabbit proximal tibial bone marrow and stimulated in vitro to start fibrocartilage differentiation lineage by bFGF and TGF ? 1. Then, collagen GAG templates enriched with these MSCs were implanted in vivo to the menisci excised rabbit knees as the substitute for the excised meniscus. After 3, 6, 12, 24 weeks postoperatively, the implants were evaluated by the gross, histological and ultrastructural observations. Results The MSCs enriched collagen GAG implants underwent inflammation, degradation, MSCs division and remodeling stages in vivo, and consequently formed a meniscus like fibrocartilage tissue. Special staining and electronic microscope observation proved that the regenerated fibrocartilage were chondrocyte like fibrochondrocytes; in contrast, the results of the control group showed that both collagen GAG implants without MSCs and no substitute had limited regenerating tissue, further evaluations by histological and electronic microscope showed no evidence of fibrochondrocytes, and hence these regenerated tissue were fibrous rather than fibrocartilaginous. Conclusion The inducing of rabbit meniscus regeneration by the autologous bone marrow derived MSCs and porous collagen GAG template is proved to be feasible in this study. However, further studies to improve the biomaterial design, to evaluate the biomechanical properties of the regenerated tissue and to ensure clinical safety etc are needed prior to its clinical application.
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Eight specimens of the knee were used to determine quadriceps force (FQ) required to stabilize the knee under load in a flexed stance.It was found that there was a positive relationship between quadriceps force and the weight and flexion of the knee .At flexion of 15? FQ was about the same as the weight; at 45?,about 3-4 times the weight.FQ increased by 10-40% after patele ctomy, while anterior displacement of the tibial tubercle by 1.5cm led to 11%-19% decrease because of its pro- longed lever arm. It widened the angle formed by the qudriceps tendon and the patellar tendon by an average of 10.7 degrees.The contact areas of the patellofemoral joint at flexion of 0-135 ? were determined by contact prints.Following anterior displacement of the tibial turbercle, contact areas were upwardly shifted and enlarged.Our results show that this procedure can decrease the patellofemoral contact stress by lengthening the lever arm of FQ, widening the angle formed by the guad-riceps tendon and patellar tendon and enlarging contact areas of the patellofemoral joint. We recommend it as a possible satisfactory treatment for the patellofemoral joint disorders