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[目的]为定制肿瘤型股骨远端假体断裂提供一种简单有效的翻修方法,即SPRS (socket-type prosthetic revision system,SPRS)假体.评价其套接部分的生物力学稳定性,初步确定适用范围,回顾性分析临床应用效果.[方法]制作SPRS假体套接部分实验标本共6套,按固定长度分成6组;用骨水泥及挤压螺钉将其重复套接、固定3次,微机控制电子万能实验机分别进行测试,比较各方向位移及角度变化,初步确定其最短有效固定长度;回顾性分析临床上应用该假体行翻修手术的病例,评价其应用效果.[结果] SPRS假体不同长度的套接部分(10、20、30、40、50、70 mm)平均拉伸(压缩)刚度组间比较差异有统计学意义(P＜0.05);平均扭转刚度组间比较差异有统计学意义(P＜0.05).固定长度为30 mm的标本,完成疲劳实验后未发生松动及破坏,30 mm及以上的固定长度满足实验要求.应用该假体行有限翻修手术的病例术后分别随访26、128个月,影像学检查发现均固定牢固、无松动,至末次随访MSTS肢体功能评分分别为63.3％、83.7％.[结论]对于殷骨远端定制肿瘤假体自髓外柄断裂、髓内柄固定牢固的病例可应用SPRS假体行有限翻修手术,生物力学测试发现该假体要求残留髓外柄固定长度应不少于30mm.虽然临床应用例数较少,最长近1 1年的随访证实了该假体的可靠性.“,”[Objective] To investigate the biomechanical stability and clinical outcome of a self-developed distal femoral socket-type prosthesis revision system (SPRS) for the revision of extramedullary stem fracture.[Methods] Six sets of simulated experiment specimens fixed with SPRS were prepared and classified into six groups according to the fixation length.The bone cement and screws were used for muff coupling and fixation for three times.Biomechanical tests were made for each specimen with universal testing machine respectively to observe the shift/angle changes in different direction and determine the shortest effective fixation length.Two clinical cases performed with SPRS were followed up for 26 months,128 months respectively,the application outcome of SPRS was recorded.[Results] The average tensional (compressional) stiffness of the socket part of SPRS with different length (10 mm,20 mm,30 mm,40 mm,50 mm,70 mm) had statistically significant differences between each two groups (P＜0.05).The average torsional stiffness also had statistically significant differences among the group (P＜0.05).The specimen with 30mm SPRS completed three point bending fatigue test of 3million circulations successfully without looseningor damage,therefore,was considered the best length meeting the requirement of experiment.The two cases receiving limited revision operation with SPRS were found still with firm fixation and no loosening occurred during the follow-up,and MSTS limb function score were 63.3％、83.7％,respectively.[Conclusion] For the extramedullary stem fracture cases,the length of SPRS prostheses should be not less than 30mm.In the clinical cases observation,nearly 11 years of followup has confirmed its reliability.However,more large number cases observation is still needed.