股骨远端肿瘤型假体近端骨折的临床治疗及三维有限元分析  

Clinical result and finite element analysis of peri-prosthetic fractures after a tumor-knee prosthesis arthroplasty in proximal femur

作　　者：杨阳[1] 许宋锋[1] 于秀淳[1] 

机构地区：[1]济南军区总医院骨病科,济南250031

出　　处：《中国矫形外科杂志》2013年第2期163-167,共5页Orthopedic Journal of China

摘　　要：[目的]探讨股骨远端肿瘤型假体置换术后假体近端骨折的力学因素以及应用环抱器治疗的可行性。[方法]回顾分析本科2008年7月～2011年1月间所治疗的2例肿瘤型膝关节假体置换术后股骨假体近端骨折病例,均通过切开复位植骨内固定的方式予以治疗并进行定期随访,观察骨质愈合情况;利用MSTS肢体功能评分进行评价。利用CT数据,建立股骨远端40%骨缺损的复合假体三维有限元模型,加载平地慢速(3 km/h)行走步态周期下肢4倍重量负荷,分析模型股骨的应力分布。[结果]2例患者骨折部位均在假体的近端,为螺旋形骨折。手术顺利,分别于术后5、6个月骨折愈合,术后肢体功能评分分别为25分,27分。通过对股骨模型的有限元分析,发现术后股骨高应力分布出现在假体柄尖端,且呈螺旋形分布,与临床所见的骨折类型与部位完全一致。[结论]股骨远端肿瘤型假体近端骨折的原因主要与术后股骨假体柄尖端出现高应力分布,且以压力为主有关,呈螺旋形分布;应用切开复位植骨并环抱器内固定是一种可行的临床治疗方法。[ Objective] This study was to investigate the biomechanical factors of peri-prosthetic fractures where occur in proximal femur after a tumor-knee prosthesis arthroplasty, and investigate the feasibility of embracing for clinical treatment. [ Method] The clinical results of 2 patients treated from July 2008 to January 2011 were analyzed. The 2 patients received open reduction and bone grafting to treat the peri-prosthetic fractures obscured in proximal femur after a tumor-knee prosthesis arthro- plasty,and conducted regular follow-up to observe the situation of bone healing. Data were evaluated by MSTS limb function Three-dimensional finite element models were established based on CT images. Three times of body mass load corresponding to the normal walking gait cycle（3km/h）was applied. The stress distribution in the femur model was analyzed. [ Result] The position of peri-prosthetic fractures occur in proximal and the site of fracture were all spiral fracture. The bone healing time were 5 -6 months. The limb function score was 25 points,27 points. Through the femur finite element analysis model, we found that high stress distributed by spiral-shaped in the tip of prosthesis. The type and the situation of fracture were same through clinical observation. [ Conclusion] The reason of peri-prosthetic fractures in proximal femur after a tumor-knee prosthesis arthroplasty was mainly related with the high stress（pressure-based） distributed in the tip of femoral prosthesis. This stress distribution is spiral-shaped. Open reduction and internal fixation with embracing and bone grafting to treat peri-prosthetic fractures after a tumor- knee prosthesis arthroplasty of is a viable clinical treatment.

关 键 词：假体周围骨折 膝关节肿瘤型假体 螺旋形骨折 有限元 应力分布 肢体功能 骨愈合 

分 类 号：R687.3[医药卫生—骨科学]