Jansson V
Orthopädische Klinik im Klinikum Grosshadern, Ludwig-Maximilians-Universität München.
Z Orthop Ihre Grenzgeb. 1991 Sep-Oct;129(5):389-92. doi: 10.1055/s-2008-1040262.
For an unconstrained bicondylar sledge knee prosthesis the mechanical load of the bony support is crucial. For a design of a tibial component of such a prosthesis with improved anatomical features allowing a complete cortical support of the rim of the prosthesis, a finite element study was performed. Stress reactions of the bone for different implantation modes were calculated. Irrespective of the bony support of the prosthesis, tensile stresses are always transferred at the interface prosthesis/bone into the bone. For a complete cortical support of the rim of prosthesis, the areas of tensile stress in the bone are closely related to areas of high compression stress. If there is cortical support of the prosthesis only on the medial side due to an undersized prosthesis, this is only of minor influence on the stress pattern in the bone. However, if there is cortical support of the prosthesis only on the lateral side, there are large areas of tensile stresses in the lateral compartment of the tibial plateau. However, tensile stress transfer in the tibial plateau must be regarded as unphysiologic and therefore unfavourable. Therefore, if intraoperatively complete cortical support of the prosthesis cannot be achieved a more medial cortical support of such a prosthesis should be preferred to a lateral cortical support.
对于无约束双髁滑槽膝关节假体，骨支撑的机械负荷至关重要。为设计一种具有改进解剖特征、能使假体边缘获得完整皮质支撑的此类假体的胫骨部件，进行了一项有限元研究。计算了不同植入方式下骨的应力反应。无论假体的骨支撑情况如何，拉伸应力总是在假体/骨界面处传递至骨内。为使假体边缘获得完整皮质支撑，骨内的拉伸应力区域与高压缩应力区域密切相关。如果由于假体尺寸过小仅在内侧有假体的皮质支撑，这对骨内的应力模式影响较小。然而，如果仅在外侧有假体的皮质支撑，胫骨平台外侧间室会出现大片拉伸应力区域。然而，胫骨平台内的拉伸应力传递必须被视为不符合生理情况，因此是不利的。所以，如果术中无法实现假体的完整皮质支撑，对于此类假体，更应选择在内侧提供皮质支撑而非外侧。
