Liu Shen, Liang Xiangdang, Liu Songyang, Guo Zhanshe, Wei Xing, Liang Yonghui
Department of Orthopaedics, Aerospace Center Hospital, Beijing, China.
Department of Orthopedics, General Hospital of People's Liberation Army, Beijing, China.
J Orthop Surg Res. 2025 Mar 28;20(1):319. doi: 10.1186/s13018-025-05681-8.
Design a new type of external fixation device that is small in size, high in strength, and capable of achieving the mechanical requirements for fracture healing. Verify the rationality and effectiveness of the device in treating tibial fractures through finite element analysis and biomechanical comparative tests.
Finite element simulation was performed on the new external fixation device to treat fractures, to verify whether the mechanical properties of the device meet the requirements of fracture healing. A fracture gap model was created using Sawbones to simulate midshaft tibial comminuted fractures. The experiment was divided into four groups, testing the mechanical characteristics of the new external fixation (NEF), locking compression plate (LCP), the unilateral external fixation (UEF), and the externalized locking compression plate (E-LCP). The axial compression, torsion, fatigue and ultimate load tests were performed separately. Data were collected and statistical analysis was performed to verify whether there were statistical differences between the four groups.
The finite element analysis of NEF demonstrated that the fracture end was displaced by 0.512 mm under 700 N loading, and the maximum stress value of the device was 189 MPa, which met the mechanical requirements. Axial compression tests showed that LCP (2108.596 N/mm) had the highest stiffness, and NEF (519.489 N/mm) had higher stiffness than both UEF (327.153 N/mm) and E-LCP (316.763 N/mm) (p < 0.05), but no significant difference between UEF and E-LCP (p = 0.313). There was a significant difference in mean torsional stiffness among UEF (1.412 N·m/deg), NEF (1.398 N·m/deg), LCP (1.128 N·m/deg), and E-LCP (0.838 N·m/deg). No structural failures occurred during fatigue testing spanning 108,000 cycles. In ultimate load tests, NEF withstood the highest load, followed sequentially by LCP, UEF, and E-LCP. Significant differences were found between the groups (p < 0.05), with frame bending and secondary bone fractures noted in post-test evaluations.
The NEF for tibial fractures is well-designed to meet the fracture healing requirements. It has certain advantages in comparison with other fixation methods and can be used as a new method for the treatment of tibial fractures.
设计一种尺寸小、强度高且能满足骨折愈合力学要求的新型外固定装置。通过有限元分析和生物力学对比试验验证该装置治疗胫骨骨折的合理性和有效性。
对新型外固定装置治疗骨折进行有限元模拟，以验证该装置的力学性能是否满足骨折愈合要求。使用Sawbones创建骨折间隙模型以模拟胫骨干中段粉碎性骨折。实验分为四组，测试新型外固定（NEF）、锁定加压钢板（LCP）、单侧外固定（UEF）和外置锁定加压钢板（E-LCP）的力学特性。分别进行轴向压缩、扭转、疲劳和极限载荷试验。收集数据并进行统计分析，以验证四组之间是否存在统计学差异。
NEF的有限元分析表明，在700 N载荷下骨折端位移为0.512 mm，装置的最大应力值为189 MPa，满足力学要求。轴向压缩试验表明，LCP（2108.596 N/mm）的刚度最高，NEF（519.489 N/mm）的刚度高于UEF（327.153 N/mm）和E-LCP（316.763 N/mm）（p < 0.05），但UEF和E-LCP之间无显著差异（p = 0.313）。UEF（1.412 N·m/deg）、NEF（1.398 N·m/deg）、LCP（1.128 N·m/deg）和E-LCP（0.838 N·m/deg）的平均扭转刚度存在显著差异。在跨越108,000次循环的疲劳试验中未发生结构失效。在极限载荷试验中，NEF承受的载荷最高，其次依次是LCP、UEF和E-LCP。组间存在显著差异（p < 0.05），试验后评估中观察到框架弯曲和二次骨折。
用于胫骨骨折的NEF设计良好，能够满足骨折愈合要求。与其他固定方法相比具有一定优势，可作为治疗胫骨骨折的一种新方法。
