【摘要】 目的探讨全膝关节置换术(totalkneearthroplasty,TKA)对髌骨内外倾运动的影响,及其在TKA术后膝前痛形成过程中所起的作用。方法采用6具成人尸体左侧下肢标本建立伸膝装置(股内侧、股中间、股外侧肌群按1.25∶1.5∶1的比例施以负荷)按比例负荷膝关节自由运动模型,应用激光束定位与X线摄片技术,分别测量正常膝关节与采用PFCΣ假体行人工膝关节置换术后膝关节屈曲过程中的髌骨内外倾角度。结果胫股关节屈曲30°、60°、90°、120°、150°时,以股骨滑车为参照标准,膝关节置换前后髌骨的倾斜角度分别是:0°±0°、0°±0°、0°±0°、0.24°±0.35°、-3.21°±1.80°;0°±0°、0°±0°、0°±0°、0°±0°、-1.12°±1.20°。三维空间参照系内,膝关节置换术前,膝关节屈曲0°、30°、60°、90°、120°、150°时髌骨平均外倾:0°±0°、-3.10°±2.25°、2.50°±1.07°、5.46°±2.60°、6.32°±2.16°、-2.10°±1.90°;膝关节置换术后,膝关节屈曲0°、30°、60°、90°、120°、150°时髌骨平均外倾:0°±0°、3.24°±0.35°、2.30°±1.39°、1.65°±1.17°、1.29°±1.03°、-0.86°±1.42°。结论TKA术后虽然髌骨与股骨滑车的对合关系保持正常,但在三维立体空间内髌骨的内外倾模式与幅度较未置换前发生了变化。膝关节初始屈曲时,TKA术前髌骨内倾,术后髌骨外倾,其变化的幅度与股骨假体外旋的幅度一致。膝关节屈曲60°￣120°范围内,TKA术后髌骨外倾较术前减小,而表现为相对内倾,内倾幅度与TKA术后股骨假体相对内翻的幅度一致。更多还原

【Abstract】 Objective To investigate the medial-lateral tilting of patella in two different coordinate systems before and after total knee arthroplasty (TKA). Methods Six fresh-frozen left low limbs from cadaver were tested using a modified Oxford Rig. Anatomically based multiple loading of the quadriceps mechanism was applied(Vastus medialis 24.5 N, Vastus intermedius/rectus femoris 29.4 N, Vastus lateralis 19.6 N). In a three dimensional coordinate system, patellar tilting was tracked using a custom-made Laser tracking device. The femoral trochlea was used as the other coodinate system in skyline view of patellar-femoral joint. Total knee arthroplasty was performed using PFCΣ posterior cruciate ligament substituting knee system. The tilting angles of patellar were measured before and after TKA. Results In three dimensional coordinate system, when knee flexed 30°,60°,90°,120°,150°, the patella titled :-3.10°±2.25°,2.50°±1.07°,5.46°±2.60°,6.32°±2.16°,-2.10°±1.90° respectively before total knee arthroplasty was undertaken. After total knee arthroplasty, the patella tilted 3.24°±0.35°,2.30°±1.39°,1.65°±1.17°,1.29°±1.03°,-0.86°±1.42° respectively. When femoral trochlea was taken as coordinate, the patella tilted 0°±0°,0°±0°,0°±0°,0.24°±0.35°,-3.21°±1.80°; 0°±0°,0°±0°,0°±0°,0°±0°,-1.12°±1.20° respectively both before and after TKA (Lateral patella tilting was defined as positive and medial patella tilting, negative). Conclusion Even the relationship between patella and femoral trochlea remains normal, the mode and magnitude of patellar tilting changes significantly after TKA. In early flexion of knee joint, patella tilts medially before TKA while it tilts laterally after TKA. After TKA, patella tilts less laterally than it does before TKA when a knee flexes from 60 to 120 degrees.更多还原