目的 评价一种可注射磷酸钙骨水泥(Calcium Phosphate Cement, CPC)强化股骨近端对老年骨质疏松性股骨粗隆间骨折内固定的生物力学影响。 方法 选用5对骨质疏松性股骨近端标本制作粗隆间骨折模型，以DHS固定，分为对照组与CPC强化组进行生物力学检测。结果 CPC强化组在500N应力下的轴向刚度为(691.93±18.90)N/mm，水平剪切刚度为(5553.84±27.47)N/mm，内外侧平均强度分别为(5.15±0.35)MPa，(4.13±0.24)MPa，扭转刚度为0.41，极限载荷3580±286N；对照组在500N应力下的轴向刚度为(453.45±19.75)N/mm，水平剪切刚度为3848.87±22.63 N/mm，内外侧平均强度分别(3.12±0.37) MPa ，(1.80±0.21) MPa，扭转刚度为0.35，极限载荷(2512±189)N。CPC强化组的各项力学性能均高于于对照组，差异有显著性意义（P<0.05）。 结论 以CPC对骨质疏松性股骨头内及内后侧缺损处强化可以有效提高骨质疏松性股骨粗隆间骨折内固定稳定性，降低术后并发症的风险。
Objective Objective To evaluate the biomechanical effects of using a new injectable calcium phosphate cement to consolidate the fixation of osteoporotic intertrochanteric fracture. Method Five matched pairs of human cadaver femora were used to produce the model of intertrochanteric fracture. All fractures were fixed with dynamic hip screws(DHS),and divided into two groups. In the CPC consolidation group of each pair, CPC was used to grout the hip screw and to fill the posteromedial defect. All femora were subjected to biomechanical test. Result Under the loading of 500 N, in the CPC consolidation group, the mean axial stiffness was (691.93±18.90) N/mm and the horizontal shear stiffness was (5553.84±27.47) N/mm. The mean lateral and medial strength was 5.15±0.35 MPa and (4.13±0.24) MPa. The torsion stiffness was 0.41 and the ultimate loading was (3580±286)N. In the control group, the mean axial stiffness was (453.45±19.75) N/mm, the horizontal shear stiffness was (3848.87±22.63) N/mm, the mean lateral and medial strength was (3.12±0.37) MPa and (1.80±0.21) MPa, and, the torsion stiffness was 0.35 and the ultimate loading was (2512±189)N. Consolidation fixation with CPC increased each of the biomechanical efficiency（P<0.05）. Conclusion CPC consolidation of osteoprotic femoral head and the medial defect of intertrochanteric fracture could significantly improve the overall stability and decrease the rate of postoperative complication.