Department of Orthopedics, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, China.
Department of Orthopedics, Jiangsu Province Hospital of Chinese Medicine, Nanjing, China.
Orthop Surg. 2024 Oct;16(10):2526-2538. doi: 10.1111/os.14199. Epub 2024 Sep 2.
Femoral head necrosis is a challenging condition in orthopaedics, and the occurrence of collapse is an important factor affecting the prognosis of femoral head necrosis. Sclerosis bands are known to influence the collapse of the femoral head, yet there is a lack of research on the biomechanical role of sclerosis bands in non-vascularized fibular grafting surgery. This study aims to evaluate the biomechanical impact of sclerosis bands in femoral head necrosis and their role in non-vascularized fibular grafting surgery (NVFG) using finite element analysis.
We constructed 11 finite element models based on CT scan data of a normal hip joint, simulating different sclerosis band thicknesses and defect scenarios. The models were analyzed for changes in femoral head displacement and von Mises stress. We constructed a hip joint model based on CT data from a normal hip joint, and after reconstruction, assembly, and optimization using 3-matic. We created five groups consisting of 11 finite element analysis models of the hip joint. Mesh partitioning and mechanical parameter settings were performed in ANSYS. The changes and differences in femoral head displacement and von Mises stress of these models were analyzed.
Increasing sclerosis band thickness led to reduced peak displacement of the femoral head by 28.6%, 42.9%, and 47.6%, and increased surface von Mises stress by 28.3%, 13.8%, and 13.0%, respectively. Post-surgery, peak displacement decreased in all groups compared to pre-surgery levels. Increasing sclerosis band thickness post-surgery resulted in decreased maximum von Mises stress of the femoral head by 13.9%, 3.0%, and 8.1%. Defect volume in the defect groups correlated with increased peak displacement of the femoral head by 10.0%, 30.0%, and 100.0%, and increased surface maximum von Mises stress of the femoral head by 9.3%, 14.0%, and 15.1%.
Sclerosis band formation exacerbates von Mises stress concentration on the femoral head surface. However, thicker sclerosis bands improve post-NVFG stability and mechanical performance. Larger anterior lateral sclerosis band defects significantly compromise postoperative stability, increasing the risk of collapse. Protecting the anterior lateral sclerosis band during NVFG surgery is crucial.
股骨头坏死是骨科领域的一个难题，股骨头塌陷是影响其预后的重要因素。硬化带被认为会影响股骨头塌陷，但关于硬化带在非血管化腓骨移植术（NVFG）中的生物力学作用的研究还很少。本研究旨在通过有限元分析评估股骨头坏死中硬化带的生物力学影响及其在 NVFG 中的作用。
我们根据正常髋关节的 CT 扫描数据构建了 11 个有限元模型，模拟了不同硬化带厚度和缺损情况。分析了股骨头位移和 von Mises 应力的变化。我们根据正常髋关节的 CT 数据构建了髋关节模型，然后使用 3-matic 进行重建、装配和优化。我们创建了五个组，每组包括 11 个髋关节有限元分析模型。在 ANSYS 中进行了网格划分和力学参数设置。分析了这些模型中股骨头位移和 von Mises 应力的变化和差异。
随着硬化带厚度的增加，股骨头的峰值位移分别减少了 28.6%、42.9%和 47.6%，表面 von Mises 应力分别增加了 28.3%、13.8%和 13.0%。手术后，所有组的峰值位移均较术前降低。术后硬化带厚度增加，股骨头最大 von Mises 应力降低 13.9%、3.0%和 8.1%。缺损组的缺损体积与股骨头的峰值位移增加 10.0%、30.0%和 100.0%以及股骨头表面最大 von Mises 应力增加 9.3%、14.0%和 15.1%相关。
硬化带的形成加剧了股骨头表面的 von Mises 应力集中。然而，较厚的硬化带可以提高术后 NVFG 的稳定性和力学性能。较大的前外侧硬化带缺损会显著影响术后稳定性，增加塌陷风险。在 NVFG 手术中保护前外侧硬化带至关重要。
