股骨成形术对于预防骨质疏松性髋部骨折的生物力学研究

目的：探讨股骨成形术是否可提高骨质疏松性股骨标本的抗骨折强度，进而可否预防髋部骨折；比较两种不同股骨成形方法对骨质疏松性股骨标本力学强度改变的差异，以明确成形术的最佳强化区域。方法：收集新鲜骨质疏松股骨标本18对，分为A、B两组，每组9对，并在每组中随机选取9具进行强化（A1组，B1组），相应的对侧标本作为对照组（A2组，B2组）。A1组中强化标本强化的区域为股骨头、股骨颈、股骨粗隆、转子下区，B1组中为股骨头、股骨颈、股骨粗隆区。记录骨水泥注入量并测量强化后股骨颈表面温度变化。对所有标本在模拟跌倒形态下进行生物力学测试，并记录载荷-位移曲线、标本的最终载荷，计算标本的最终能量及刚度值。比较强化组标本与相应对照组标本的生物力学差异以及两种不同强化方法对标本力学改变的差异。结果：相对于对照组，强化组标本最终载荷、最终能量均有明显提高，而刚度却无明显改变。经两种不同强化方法强化后的标本之间的最终载荷及最终能量差异无统计学意义。结论：股骨成形术具有微创、操作简捷、效果显著等优点，可作为预防骨质疏松性髋部骨折的新型手法方法推广应用。

Biomechanical study on femoroplasty-augmentation for prevention of osteoporotic hip fractures

Objective: To explore whether femoral plasty can improve the fracture resistance of osteoporotic femoral specimens and prevent hip fracture,and to compare the difference of mechanical strength changes between two different femoral plasty methods in osteoporotic femoral specimens,so as to determine the best strengthening area of the plasty.Methods: Eighteen pairs of fresh osteoporotic femur specimens were collected and divided into two groups,A and B,9 pairs in each group. Nine fresh osteoporotic femur specimens in each group were randomly selected for enhancement,and the corresponding contralateral specimens were used as control group. In group A1,the enhancement areas were femoral head,femoral neck,femoral trochanter and subtrochanteric region. And in group B1,the enhancement areas were femoral head,femoral neck and femoral trochanter region. The amount of cement injected into the femoral neck was recorded and the surface temperature of the femoral neck was measured. All specimens were biomechanically tested under simulated falls. Load-displacement curves,final loads were recorded. The final energy and stiffness of specimens were calculated. The biomechanical differences between the specimens of the enhancement group and those of the corresponding control group were compared,and the mechanical changes of the specimens by two different enhancement methods were compared.Results: Compared with the control group,the ultimate load and energy of the specimens in the enhanced group increased significantly,but the stiffness did not change significantly. There was no significant difference in final load and energy between specimens strengthened by two different methods.Conclusion: Femoral plasty has the advantages of minimally invasive,simple operation and remarkable effect. It can be used as a new method to prevent osteoporotic hip fracture.