骨质疏松影响股骨近端防旋髓内钉治疗股骨转子间骨折的有限元仿真

文题释义：骨质疏松：是骨量减少导致骨微结构破坏、进而易发生骨折的全身性疾病，它不仅是导致髋部骨折的重要原因之一，也是导致股骨近端防旋髓内钉内固定失效的重要原因之一。股骨转子间骨折：在老年人中较为常见，现主要是手术治疗，股骨近端防旋髓内钉被广泛应用于临床。股骨转子间骨折内固定术后失效时有发生，其原因可能与骨质疏松、骨折类型、尖顶距值、复位质量等密切相关。背景：股骨近端防旋髓内钉治疗股骨转子间骨折在临床应用广泛，但仍有部分术后内固定失效病例，股骨近端骨质疏松被认为是一个重要原因。Singh指数是评价股骨近端骨质疏松严重程度的一个重要指标，基于Singh指数探讨不同骨质疏松程度对股骨近端防旋髓内钉治疗转子间骨折疗效的影响，对减少内固定失效概率，增加手术成功率具有重要意义。目的：探讨不同骨质疏松程度对股骨近端防旋髓内钉治疗转子间骨折疗效的影响，为临床治疗转子间骨折提供新思路和实验基础。方法：选取1例左侧股骨转子间骨折患者的CT资料，导入Mimics 19.0和Geomagic studio 2017软件中进行提取、优化得到右侧股骨三维模型。运用Solidworks2017软件画出内固定模型并与股骨模型按照标准手术技术装配，以STEP格式导入Hypermesh 14.0软件中截骨得到AO 2.1型股骨转子间骨折模型，参照Singh指数1-6划分应力骨小梁得到A-F模型，设置材料属性参数、边界条件、施加载荷，分别储存为K文件导入LS-DYNA软件求解。结果与结论：①当股骨头受力时，Singh 6-Singh 1股骨头颈骨块中螺旋刀片产生切割，普通骨小梁消失，包裹螺旋刀片的应力骨小梁不但没有消失，且承载和分散了部分应力，使得螺旋刀片仍具有较大的接触面积和把持力，维持着骨折的复位，减少了股骨头颈骨块的内翻和旋转；②从Singh 6-Singh 1，随着应力骨小梁的消失，骨质疏松越严重，股骨近端防旋髓内钉治疗股骨转子间骨折就越容易失效；③股骨近端海绵状的丰厚骨小梁，特别是应力骨小梁，通过抵抗、缓冲弯曲应变而在维持股骨的弹性稳定起着重要作用，是股骨近端弹性稳定的重要结构。ORCID: 0000-0002-4097-2790(黄培镇)中国组织工程研究杂志出版内容重点：人工关节；骨植入物；脊柱；骨折；内固定；数字化骨科；组织工程

Osteoporosis effects on the treatment of intertrochanteric fracture of femur with proximal femoral anti-rotation intramedullary nail:a finite element simulation

BACKGROUND:Proximal femoral anti-rotation intramedullary nail for treating intertrochanteric fracture is widely used in clinical practice,but there are still some cases of failure of internal fixation after operation,and osteoporosis of proximal femur is considered as an important reason.Singh index is an important index to evaluate the severity of osteoporosis in the proximal femur.Based on the Singh index,it is of great significance to explore the effect of different degrees of osteoporosis on the treatment of intertrochanteric fracture with anti-rotation intramedullary nail in the proximal femur,so as to reduce the failure rate of internal fixation and increase the success rate of operation.OBJECTIVE:To explore the effect of different osteoporosis on the treatment of intertrochanteric fracture with proximal femoral anti-rotation intramedullary nail,so as to provide new ideas and experimental basis for clinical treatment of intertrochanteric fracture.METHODS:CT data of one patient with intertrochanteric fracture of the left femur were imported into Mimics 19.0 and Geomagic studio 2017 software to extract and optimize the three-dimensional model of the right femur.SolidWorks 2017 software was used to draw the internal fixation model and assemble it with the femur model according to the standard operation technology,and import it into HyperMesh 14.0 software in STEP format to cut the bone according to AO-2.1 type of intertrochanteric fracture.Trabecular bone based on Singh index 1-6 was established to obtain six models of A-F.Material property parameters,boundary conditions and applied loads were set.Finally,the data were stored as K files and imported into LS-DYNA software for solution.RESULTS AND CONCLUSION:(1)When the femoral head was stressed,the spiral blade in the bone block of the femoral head and neck of Singh 6-Singh 1 was cut,the common bone trabecula disappeared,the stress bone trabecula wrapped with the spiral blade did not disappear,but loaded with certain stress,so that the spiral blade still had a large contact area and holding force,maintained the reduction of the fracture,and reduced the varus and rotation of the bone block of the femoral head and neck.(2)From Singh 6-Singh 1,with the disappearance of stress bone trabecula,the more serious osteoporosis is,the more likely failure will be in the treatment of intertrochanteric fracture with proximal femoral anti-rotation intramedullary nail.(3)The spongy bone trabeculae,especially the stress bone trabeculae,play an important role in maintaining the elastic stability of the proximal femur by resisting and buffering the bending strain.