Teubner E, Kottmann B
Chirurg. 1976 Dec;47(12):674-81.
The static behavior of various types of endoprostheses in partial or total hip replacements were tested by means of geometrical analysis in order to examine the loosening phenomena. -- The 3 heterogenous structural materials with highly differing elastic modules such as methylmetacrylate, steel, and bone, which are presently still necessary for the firm embedding of hip prosthesis, are the decisive factors in the observed loosening and migrating of hip arthroplastics. Deformation and fracture of methylmetacrylate alter the primary stabilization of femoral components, changing a two-point fixational system (a two-armed handle) into a device firmly fixed only at one side, thereby increasing the bending and stretching moments so that loosening, varus migration, and metal fatique may occur. -- Prostheses with long-shaft femoral components, with a great surface pressure, and a great momentum of resistance in the upper, endangered third part as well as prosthesis collars up to 65 degrees, are therefore preferable in order to avoid implant complications.
通过几何分析测试了各种类型的髋关节置换内植物在部分或全髋关节置换中的静态行为，以研究松动现象。——目前髋关节假体牢固植入仍需的三种弹性模量差异很大的异质结构材料，即甲基丙烯酸甲酯、钢和骨，是观察到的髋关节置换松动和移位的决定性因素。甲基丙烯酸甲酯的变形和断裂会改变股骨部件的初始稳定性，将两点固定系统（双臂柄）转变为仅一侧牢固固定的装置，从而增加弯曲和拉伸力矩，进而可能发生松动、内翻移位和金属疲劳。——因此，为避免植入并发症，采用长柄股骨部件、表面压力大、上部危险的三分之一部分阻力矩大以及假体颈角度达65度的假体更为可取。
