股骨髁髌股、胫股关节运动重叠接触区域及其生物力学测定

目的 :明确膝关节运动时胫骨、髌骨与股骨髁接触的重叠区域 ,测量并比较分析重叠区域内髌股、胫股关节各自接触压大小及分布特点 ,探讨髌股关节置换术中股骨滑车假体长度的设计。方法 :收集 8具新鲜膝关节尸体标本 ,在Instron 85 0 1生物力学测试仪上构建实验平台 ,模拟生理状态下膝关节站立到下蹲屈膝的过程 ,采用染色法描记重叠区域、压敏法测量髌股、胫股关节在该区域接触压。结果 :股骨髁关节面存在髌股、胫股关节运动重叠接触区域 ,范围大致相当股骨髁髌股关节接触区域内、始于屈膝 75°髌股接触部的后部分区域 ;重叠区域内髌股、胫股关节各自接触压测定显示 ,前者的接触压明显高于后者。结论 :股骨滑车假体的有效长度应涵盖髌股关节在股骨髁所有接触区域。

Determination of the Overlapping Area of Patellofemoral and Tibiofemoral Joint Sliding above the Femoral Condylar Facet and the Biomechanical Property of the Area

Objective: To determine the overlapping area of the femoral condyle facet on which the patellofemoral and tibiofemoral joint surfaces move and to measure the pressures on such area in order to better design the length of femoral trochlea prosthesis in patellofemoral arthroplasty. Methods: Eight fresh cadaver knees were mounted on Instron 8501 biomechanics tester,and simulated physiologically weight-bearing situation of knee from standing to flexion position. Such overlapping area was drawed up with stain method and the contact pressures were measured with Fuji pressure film. Results: There existed an overlapping contact area on the femoral condyle facet within the patellofemoral contact area when knee flexion was 75° or larger. The tibiofemoral contact pressure was higher than the patellofemoral pressure in the area. Conclusion: The femoral trocher prosthesis should cover the whole contact area of patellofemoral joint.