Zhang Rui, Luo Peng, Hu Wei, Ke Chenrong, Wang Jianshun, Guo Xiaoshan
Department of Orthopaedics, the Second Affiliated Hospital of Wenzhou Medical University, Wenzhou Zhejiang, 325027, P.R.China.
Department of Orthopaedics, the Second Affiliated Hospital of Wenzhou Medical University, Wenzhou Zhejiang, 325027,
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2017 Feb 15;31(2):165-170. doi: 10.7507/1002-1892.201609103.
To evaluate the biomechanical properties of proximal femoral medial buttress plate (PFMBP) for fixing the reverse oblique intertrochanteric fractures by comparing with proximal femoral locking compression plate (PFLCP) and proximal femoral nail antirotation (PFNA).
Eighteen synthetic femoral bone models (Synbone) were divided into 3 groups (group PFLCP, group PFNA, and group PFMBP), 6 models in each group; an AO 31-A3.1 reverse oblique femoral intertrochanteric fracture was made based on the same criterion. After being fixed and embeded, the axial load testing, torsion testing, and axial load-to-failure testing were performed on each model. The axial displacement of different loads, torque of different torsion angles, and failure load of each model were recorded, and the stiffness of axial load and torsion were calculated.
The axial stiffness in groups PFLCP, PFNA, and PFMBP were (109.42±30.14), (119.13±29.14), and (162.05±22.05) N/mm respectively, showing significant differences between groups ( <0.05). There were significant differences in torque between different torsion angles in the same group, as well as in the torque between groups at the same torsional angle ( <0.05). The torsion stiffness in groups PFLCP, PFNA, and PFMBP were (1.45±0.44), (1.10±0.13), and (1.36±0.32) N·mm/deg respectively; there were significant differences when compared groups PFLCP and PFMBP with group PFNA ( <0.05), but no significant difference was found between group PFLCP and group PFMBP ( >0.05). The failure loads of groups PFLCP, PFNA, and PFMBP were (1 408.88± 0.17), (1 696.56±0.52), and (2 154.65±0.10) N respectively, showing significant differences between groups ( <0.05).
The newly-designed PFMBP is better than PFNA and PFLCP in axial load stiffness and torsion stiffness for fixing reverse oblique intertrochanteric fracture by biomechanical test, indicating that reconstruction of medial stability is a key element for unstable intertrochanteric fracture.
通过与股骨近端锁定加压钢板（PFLCP）和股骨近端抗旋髓内钉（PFNA）比较，评估股骨近端内侧支撑钢板（PFMBP）固定反斜行转子间骨折的生物力学性能。
将18个合成股骨骨模型（Synbone）分为3组（PFLCP组、PFNA组和PFMBP组），每组6个模型；按照相同标准制造AO 31-A3.1型反斜行股骨转子间骨折。固定并植入后，对每个模型进行轴向载荷测试、扭转测试和轴向载荷至失效测试。记录不同载荷下的轴向位移、不同扭转角度下的扭矩以及每个模型的失效载荷，并计算轴向载荷和扭转的刚度。
PFLCP组、PFNA组和PFMBP组的轴向刚度分别为（109.42±30.14）、（119.13±29.14）和（162.05±22.05）N/mm，组间差异有统计学意义（<0.05）。同一组内不同扭转角度间的扭矩以及相同扭转角度下组间扭矩差异均有统计学意义（<0.05）。PFLCP组、PFNA组和PFMBP组的扭转刚度分别为（1.45±0.44）、（1.10±0.13）和（1.36±0.32）N·mm/deg；PFLCP组和PFMBP组与PFNA组比较差异有统计学意义（<0.05），但PFLCP组和PFMBP组之间差异无统计学意义（>0.05）。PFLCP组、PFNA组和PFMBP组的失效载荷分别为（1408.88±0.17）、（1696.56±0.52）和（2154.65±0.10）N，组间差异有统计学意义（<0.05）。
通过生物力学测试，新设计的PFMBP在固定反斜行转子间骨折的轴向载荷刚度和扭转刚度方面优于PFNA和PFLCP，表明重建内侧稳定性是不稳定转子间骨折治疗的关键因素。
