钽棒联合带血管蒂髂骨瓣转移治疗股骨头缺血性坏死的有限元研究

摘要

背景:钽棒联合带血管蒂髂骨瓣转移治疗股骨头缺血性坏死的近期临床效果满意,然而目前其相关生物力学特性变化的报道较少.目的:探索钽棒联合带血管蒂髂骨瓣转移治疗股骨头缺血性坏死的力学安全性及有效性.方法:选取单侧ARCOⅢa期股骨头坏死并行带血管蒂髂骨瓣转移患者1例,术前及术后6个月行股骨近段的螺旋CT扫描.应用专业医学建模软件Mimics及逆向工程软件Geomagic建立正常组、坏死组、钽棒联合骨瓣修复组三组有限元模型.应用有限元分析软件Msc.Patran分析不同载荷下股骨近端的力学特性变化.结果:三组模型与实际股骨的情况完全吻合.坏死模型呈囊性变的压力骨小梁与正常骨小梁交界处存在应力集中.钽棒联合骨瓣修复模型股骨近端的力学特性接近正常,结果明显优于坏死模型.结论:钽棒联合带血管蒂髂骨瓣转移治疗股骨头缺血性坏死是安全、有效的手术方案.%Background:Vascularized iliac bone flap transplantation combined with tantalum screw has highly short-term clinical success rate for treatment of osteonecrosis of the femoral head (ONFH), but the reports regarding the biomechanical safety and efficacy are rare. Objective:To explore biomechanical safety and efficacy of tantalum screw combined with vas-cularized iliac bone flap grafting for the treatment of ONFH. Methods:A patient suffered from ONFH (ARCOⅢa) was se-lected and treated with tantalum screw combined with vascularized iliac bone flap grafting. 64 CT scanning was performed on the upper femur preoperatively and 6 months postoperatively. Three finite element models (normal model, ONFH model and tantalum screw combined with bone grafting model) were built up with Mimics and Geomagic software. The biome-chanical effects of the upper femur were analyzed under different loadings with Msc.Patran software. Results: The three models matched with the actuality of the femur. The strain concentrated on the juncture between bone trabecula associated cystic and normal bone trabecular. The mechanical property of tantalum screw combined with bone flap model was similar to that of normal model, which was superior to the ONFH one. Conclusions:Tantalum screw combined with vascularized ili-ac bone flap grafting is a safe and effective option for the treatment of ONFH.