骨水泥强化型PFNA对老年性股骨粗隆间骨折的生物力学研究

摘要

Objective To analysis the biomechanical role of bone cement enhanced PFNA in the treatment of senile intertrochanteric fracture, and to provide theoretical basis for clinical treatment.Methods8 specimens of ipsilateral intertrochanteric fracture in the aged cadavers were caused by AO fracture classification of AO31-A2.3 type,and randomly divided into the control group and the observation group,every group had4 specimens. The control group were treated by PFNA,and the observation group were treated by bone cement enhanced PFNA. Two groups of specimens were subjected to compressive loading experiment with universal material testing. The maximum loading force and the limit loading force were observed,the distance between fracture ends,the distance of fracture dislocation and the sliding distance of the fracture fragments along the intertrochanteric were measured with calipers.Results The maximum loading force,the limit loading force,the distance of fracture dislocation and the sliding distance of the fracture fragments of the observation group were(1313.8±97.07)N,(2432.5±117.65)N,(0.05±0.02)mm,(1.07±0.43)mm. The maximum loading force of the two groups were not significant differences(P>0.05),but the limit loading force was larger than the control group(P<0.05). But the distance of fracture dislocation and the sliding distance of the fracture fragments of the observation group were less than the control group(P<0.05).ConclusionSenile intertrochanteric fracture treated by bone cement enhanced PFNA doesn't affect weight-bearing force,but can make fracture stronger,improve the stability and reduce fretting.So it can improve the clinical effect of surgical treatment of senile intertrochanteric fracture.%目的 探讨骨水泥强化型PFNA对老年性股骨粗隆间骨折的生物力学作用,为临床治疗提供理论依据.方法 采用老年尸体同侧股骨标本8具,均造成股骨粗隆间骨折AO31-A2.3型骨折,随机分为对照组(PFNA)和观察组(骨水泥强化型PFNA),每组各4具,分别按照标准手术方式进行内固定治疗,两组股骨标本采用万能材料测试机进行压缩载荷实验,观察比较两组股骨标本的最大载荷力及极限载荷力,并采用高精度显光栅位移测微仪测量骨折断端在压缩至最大载荷时的间隔位移情况及骨折远、近端沿粗隆间的滑动位移情况.结果 观察组最大载荷力(1313.8±97.07)N,极限载荷力(2432.5±117.65)N,骨折端间隔压缩位移为(0.05±0.02)mm,滑动位移为(1.07±0.43)mm,其中观察组最大载荷力大于对照组,但差异无统计学意义(P>0.05),极限载荷力明显大于对照组,差异有统计学意义(P<0.05),压缩后观察组标本的骨折端间隔压缩位移和滑动位移均明显小于对照组,差异均有统计学意义(P<0.05).结论 骨水泥强化型PFNA治疗老年性股骨粗隆间骨折不影响负重力,能够使骨折端更坚强,提高骨折端的稳定性,减少骨折端的微动,提高手术治疗老年性股骨粗隆间骨折的临床效果.