The Experimental Study Of Chinese Morphological Characters Of Patellae And Patellar Prosthesis Design

The Experimental Study of Morphological Characters ofPatellar and patellofemoral prosthesis design Objective To charaterize of our study is to patellar cartilage surface in normal Chinese people , explore the correlation of the lateral and medial patellofemoral contact area on patellar cartilage surface, as well as prosthesis design of the patellofemoral joint. Methods The shape of 200 patella of Chinese people were classified according to the system of Wiberg using radiographs made with knee in 40 degrees of flexion. Five fresh cadaver knees with WibergII patellae were mounted on Instron 8501 so that life-like force of weight-bearing were simulated the kinematitical process from standing to high flexion. Determine the lateral and medial patellofemoral contact area on patellar cartilage surface and find out the location of patellofemoral contact area in five flexion degrees of knee with Fuji pressure sensitive film. Results 1) Among the 200 Chinese people , there were 3 Wiberg I patellas(1.5%); 115 Wiberg II (67. 5%) ; 76 WibergIII (38.5 %) ;and 6 WibergIV (3%) . 2) The lateral patellofemoral contact area was statistically larger than medial contactarea(P<0. 01). 3) Correlation between the area of the patellar cartilage and the patellofemoral contact area was statistically significant(P<0.01). Conclusion When developing patellar prosthesis design, the morphological characters of patellar cartilage surface and kinematical value should be taken into account.