Posterior stabilized knee prosthesis of different types：comparison of intercondylar osteotomy amount / 中国组织工程研究

ABSTRACT

BACKGROUND:Posterior stabilized femoral knee prosthesis needs additional condyle osteotomy to accommodate the tibial post and femur fossa structures. Intercondylar fossa on both sides connected at the femoral body with concentrated stress is a place easily affecting fractures. Differences in bone mass between different models of different brands did not have specific data, which was not convenient to select prosthesis for clinicians. OBJECTIVE: To compare the difference of intercondylar osteotomy data among clinical commonly used posterior stabilized knee prostheses (six imported and domestic brands), and to provide basis for the selection and application of the prostheses. METHODS:The current commonly used posterior stabilized knee prostheses (six imported and domestic brands) were used, including Zimmer NexGen LPS, Stryker Scrorpio NRG Knee-Flexed, Depuy PFC Sigma, Smith & nephew Genesis-2 PS, United-U1 and Wego GKPS. According to the osteotomy template, the osteotomy-surfaces consisting of femoral condyle starting section and cross section, distal section of femoral condyle, and back-oblique section were identified. The corresponding femoral prosthesis diameter lines included condylar ambilateral and anteroposterior diameters, width and depth of femoral intercondylar fossa. The above data were compared and measured. RESULTS AND CONCLUSION:The six kinds of knee femoral prostheses were different in ratio of ambilateral diameter and anteroposterior diameter, bone resection of intercondylar fossa, and geometry. Imported prostheses carry shorter diameters in femoral starting and cross sections, so it can catch more posterior condylar osteotomy. With increasing prosthesis sizes, the ratio of bone loss causing by width of intercondylar osteotomy is decreased among six brands. In al sizes, Stryker Scrorpio NRG Knee-Flexed catches shorter width of intercondylar osteotomy. Knee prosthesis osteotomy among six brands is different. The result of this study is not sufficient to evaluate the pros and cons between different prostheses, but as reserving bone is concerned, the design of less intercondylar osteoomy catches more advantages.