目的通过有限元分析方法比较新型交锁髓内钉（nIMN）与传统交锁髓内钉（tIMN）固定AO分型32-A3型股骨干骨折的生物力学稳定性。
方法选择1例健康成年男性志愿者，30岁，体重为70 kg，采集股骨CT扫描数据，应用Mimics 17.0软件和Geomagic Studio软件建立股骨三维有限元模型，模拟AO分型为32-A3a型（上1/3）、32-A3b型（中1/3）、32-A3c型（下1/3）股骨干骨折，并分别与nIMN、tIMN装配。模拟垂直站立、缓步行走、快速行走、下楼梯4种载荷状态，在同一工况下比较2种髓内钉固定方案股骨干骨折断端的位移及应力分布情况，分析各骨折模型不同固定方案的稳定性。
结果在模拟4种载荷时，骨折断端位移平均为0.129 mm，最大应力值平均为111.00 MPa，最小的断端位移、最大应力值分别为0.014 mm、29.48 MPa，均为垂直站立时股骨干下1/3骨折采用nIMN固定，最大的断端位移、最大应力值分别为0.325 mm、242.98 MPa，均为下楼梯时股骨干上1/3骨折采用tIMN固定。对于股骨干上、中、下1/3骨折，不论采用tIMN或nIMN固定，断端位移、最大应力值均随载荷量增加呈现上升趋势，其中上1/3骨折尤为明显。与tIMN相比，nIMN固定股骨干上、中、下1/3骨折的断端位移、最大应力值均更小。以下楼梯载荷为例：股骨整体最大应力值均出现在股骨近端亚当斯弧及其周围部分，范围值为86.62~242.98 MPa；骨折断端最大应力值范围为0.44~56.49 MPa，应力主要集中在内侧部分，且随着股骨上、中、下1/3骨折呈现递减趋势。
结论对于AO分型32-A3型股骨干骨折，nIMN固定较tIMN固定的骨折断端位移和最大应力值均更小，抗旋转稳定性更好。
ObjectiveTo compare the biomechanical stability of a novel interlocking intramedullary nail (nIMN) with that of a traditional interlocking intramedullary nail (tIMN) in the treatment of type AO 32-A3 femoral shaft fractures using a finite element analysis.
MethodsA healthy adult male volunteer, aged 30 years old and weighing 70 kg, was selected for collection of his CT scan data of the femur. A three-dimensional finite element model of the femur was established using software Mimics 17.0 and Geomagic Studio. After femoral shaft fractures of AO/OTA types 32-A3a, 32-A3b, and 32-A3c were simulated, nIMN and tIMN were assembled respectively. After boundary conditions and material properties of the models were set based on reference literature, 4 load states were simulated: vertical standing, slow walking, fast walking, and descending stairs. The displacements and stress distribution at the femoral fracture ends under the same conditions were compared between nIMN and tIMN schemes of fixation. The stabilities of each fracture model at different fixation schemes and load states were analyzed.
ResultsIn the 4 load states simulated, the displacements of the fracture ends averaged 0.129 mm, and the maximum stresses 111.00 MPa. The smallest displacement and maximum stress (0.014 mm and 29.48 MPa) were found in the vertical standing in the femoral shaft fracture of type 32-A3c fixed with nIMN. The largest displacement and maximum stress (0.325 mm and 242.98 MPa) were found in descending stairs in the femoral shaft fracture of type 32-A3a fixed with tIMN. In femoral shaft fractures of types 32-A3a, 32-A3b, and 32-A3c, regardless of tIMN or nIMN fixation, the displacement and maximum stress increased with the load, with the femoral shaft fracture of type 32-A3a being particularly evident. nIMN fixation resulted in lower displacements and maximum stresses in AO/OTA types 32-A3a, 32-A3b, and 32-A3c than tIMN fixation. Taking descending stairs as an example, the overall maximum stress occurred on the proximal part of the femur and the surrounding area of Adams'arc, with the maximum stress fluctuating between 86.62 and 242.98 MPa. The maximum stress at the fracture end fluctuated between 0.44 and 56.49 MPa. The stress mainly concentrated on the medial part, and decreased from type 32-A3a to type 32-A3b to type 32-A3c.
ConclusionIn type AO 32-A3 femoral shaft fractures, nIMN leads to a smaller fracture end displacement and a lower maximum stress than tIMN, indicating better rotational stability.
陈培生,林朝晖,林凤飞,等. 新型交锁髓内钉固定AO分型32-A3型股骨干骨折的有限元分析[J]. 中华创伤骨科杂志,2025,27(03)：228-233.
DOI:10.3760/cma.j.cn115530-20241231-00517版权归中华医学会所有。
未经授权，不得转载、摘编本刊文章，不得使用本刊的版式设计。
除非特别声明，本刊刊出的所有文章不代表中华医学会和本刊编委会的观点。
陈培生、林朝晖：研究实施、数据采集、论文撰写；林凤飞：研究设计、技术支持与指导；陈宾、林东泽、郑科：研究实施
文档即答
智问智答
机器翻译
你好，我可以帮助您更好的了解本文，请向我提问您关注的问题。
