Orthopedics Dept. of 1st Affiliated Hospital, GuangZhou Medical University, GuangDong, China.
Orthopedics Dept. of HuiDong People's Hospital, HuiZhou, GuangDong, China.
J Invest Surg. 2020 Jun;33(5):428-437. doi: 10.1080/08941939.2018.1533054. Epub 2018 Dec 5.
Little is known about how biomechanics govern the five fixtures such as DHS, MLS, DHS + LS, LP, and HA are accepted as common therapeutic techniques. A series of numerical models for a femoral neck fracture of Pauwels-I will be constructed by innovative approach of finite element in order to determine the most optimized option in comparison with biomechanical performance. Twenty sets of computer tomography scanned femora were imported onto Mimics to extract 3 D models; these specimens were transferred to Geomagic-Studio for a simulative osteotomy and kyrtograph; then, they underwent UG to fit simulative solid models; 5 sorts of fixture were then expressed by Pro-Engineer virtually. After processing with HyperMesh, all compartments (fracture model + internal implant) were assembled onto 5 systems: "Dynamic Hip Screw (DHS), Multiple Lag screw (MLS), DHS + LS, femoral Locking Plate (LP) and HemiArthroplasty (HA)." Eventually, numerical models of the finite-elemental analysis were exported to AnSys to determine the solution. Four models of fixation and a simulation of HA for Pauwels-I were established, validated, and analyzed with the following findings: In term of displacement, these 5 fixtures ranged between 0.3801 and 0.7536 mm have no significant difference; in term of stress, the averages of peaks for integral assemblage are b(MLS) = 43.5766 ≈< d(LP) = 43.6657 ≈< e(Ha) = 43.6657 < c(DHS + LS) = 66.5494 < a(DHS) = 105.617 in MPa indicate that MLS, LP and HA are not significantly different, but less than DHS + LS or DHS in each. A fixture of MLS or LP with optional HA should be recommended to clinically optimize a Pauwels-I facture.
关于生物力学如何控制 DHS、MLS、DHS+LS、LP 和 HA 等五种固定器，人们知之甚少，这些固定器被认为是常见的治疗技术。通过有限元的创新方法，为 Pauwels-I 股骨颈骨折构建了一系列数值模型，以确定与生物力学性能相比最优化的选择。将 20 组计算机断层扫描股骨导入 Mimics 以提取 3D 模型；这些标本被转移到 Geomagic-Studio 进行模拟截骨和 Kyrtograph；然后，它们经过 UG 拟合模拟实体模型；然后，通过 Pro-Engineer 虚拟表达 5 种固定器。经过 HyperMesh 处理后，所有的隔室（骨折模型+内部植入物）都被组装到 5 个系统中：“动力髋螺钉（DHS）”、“多枚拉力螺钉（MLS）”、“DHS+LS”、“股骨锁定板（LP）”和“半髋关节置换（HA）”。最后，将有限元分析的数值模型导出到 AnSys 以确定解决方案。建立、验证和分析了 Pauwels-I 的 4 种固定模型和 HA 的模拟模型，结果如下：在位移方面，这 5 种固定器的位移在 0.3801 和 0.7536mm 之间，没有显著差异；在应力方面，整体装配的峰值平均值为 b（MLS）=43.5766≦<d（LP）=43.6657≦<e（HA）=43.6657< c（DHS+LS）=66.5494< a（DHS）=105.617MPa ，表明 MLS、LP 和 HA 没有显著差异，但低于 DHS+LS 或 DHS 。临床上应推荐使用 MLS 或 LP 加可选 HA 的固定器来优化 Pauwels-I 骨折。
