国人髌骨的髌股接触率比较及其意义

Comparison of patellofemoral contact ratio of patellar cartilage surface in Chinese

目的 研究正常国人髌骨内外侧软骨面的髌股内外侧接触率，探讨其在国入髌骨假体设计中的意义。方法 选取WibergⅡ型的新鲜冷冻膝关节尸体标本10具，利用Instron8501生物力学测试仪，模拟生理状态下膝关节屈伸过程，用压敏片法测量各屈膝度髌骨内外侧软骨面的髌股接触面积，计算出髌股接触率。结果 各屈膝度髌骨外侧软骨面的髌股接触率明显大于内侧（P〈0.01），屈膝早期（20°～60°）甚至高出1～2倍。结论 在国人髌股关节假体的设计中，其髌骨假体应以WibergⅡ型为模板，采取偏心型设计，将更符合国人髌骨的形态学特征。

Objective To compare patellofemoral comtact ratio of parella and explore the correlation of the lateral and medial patellofemoral contact ratio on patellar cartilage surface, as well as prosthesis design of the patellofemoral joint. Methods Five fresh cadaver knees with Wiberg Ⅱ patellae were mounted on Instron 8501 so that life-like force of weight-bearing was simulated the kinematitical process from standing to high flexion. The lateral and medial patellofemoral contact ratio on patellar cartilage surface was determined and the location of patellofemoral contact ratio has measured in five flexion degrees of every knee with Fuji pressure sensitive film. Results The lateral patellofemoral contact ratio was statistically larger than medial contact ratio （P 〈 0. 01 ）. When knee was flexed from 20°to 60° , the lateral patellofemoral contact ratio was larger than 2 times or 3 times of medial contact ratio. Conclusions When de- veloping Chinese patellar prosthesis design, the morphological characters of patellar cartilage surface and kinematical value in Chinese should be taken into account.