Shaw J A, Moulton M J
George Washington University Medical Center, Washington, DC, USA.
Am J Orthop (Belle Mead NJ). 1996 Jun;25(6):429-36.
The biomechanical basis for high tibial osteotomy (HTO) is erroneously conceived, in that to unload the medial side of the knee, an osteotomy would have to be performed of sufficient magnitude to shift the lateral side of the knee joint far enough medially to intersect the dynamic axis, not the mechanical axis. The resulting angular deformity would be functionally and cosmetically unacceptable in the eyes of most patients and surgeons. To corroborate these theoretic considerations, and to define the angular deformity necessary to unload the medial side of the knee joint during the midstance phase of gait, a cadaver osteotomy model was used with compartmental loading defined by direct observation, as well as by load-sensitive film. As predicted, medial compartment unloading did not occur until the lateral side of the joint crossed the dynamic axis. In both cadavers tested, the extremity alignment necessary to unload the medial side was approximately 25 degrees valgus. The efficacy of HTO should be re-examined, as its biomechanical basis is fundamentally flawed.
高位胫骨截骨术（HTO）的生物力学基础存在错误认知，即要减轻膝关节内侧的负荷，截骨的幅度必须足够大，以使膝关节外侧向内侧移动足够远，从而与动态轴而非机械轴相交。在大多数患者和外科医生看来，由此产生的角度畸形在功能和美观上都是不可接受的。为了证实这些理论考量，并确定在步态中期阶段减轻膝关节内侧负荷所需的角度畸形，使用了尸体截骨模型，通过直接观察以及负荷敏感胶片来定义关节间室负荷。正如所预测的，直到关节外侧越过动态轴，内侧间室负荷才会减轻。在测试的两具尸体中，减轻内侧负荷所需的下肢对线约为外翻25度。由于其生物力学基础存在根本性缺陷，HTO的疗效应重新审视。
