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[目的]探讨磷酸钙复合BMP-2对骨质疏松状态下椎弓根螺钉稳定性的影响, 评价其临床应用价值.[方法]雌性新西兰大白兔卵巢切除去势法制备骨质疏松模型, 测量骨密度.将兔随机分为增强组和常规组, 增强组采用磷酸钙复合BMP-2注入增强后置入椎弓钉, 而常规组采用常规技术置入椎弓钉.置钉后4、8和12周分别进行骨组织形态计量检查和生物力学检测.[结果]与术前比较, 卵巢切除后6个月的BMD显著下降 (P＜0.05), 提示骨质疏松模型建立成功.置入L3椎弓螺钉术后4、8和12周, 增强组和常规组骨形态计量指标比较, 类骨质表面、骨-螺钉接触、骨内生和骨矿物沉积速率, 均随时间延长显著增加, 相同时间点增强组各项指标优于常规组, 差异有统计学意义 (P＜0.05) .生物力学测试表明, 置钉后4、8和12周, 随着固定时间延长, 两组的最大拔出力和最大破坏功耗均显著增加, 相同时间点, 增强组的最大拔出力和最大破坏功耗均显著大于常规组, 差异有统计学意义 (P＜0.05) .[结论]磷酸钙复合BMP-2可以增强椎弓根螺钉在骨质疏松椎体中的稳定性, 具有一定的临床应用价值.“,”[Objective] To explore the effect of calcium phosphate composited with bone morphogenetic protein-2 (BMP-2) on the stability of pedicle screws in osteoporotic rabbit, and evaluate its significance in clinical setting. [Methods] Healthy female adult New Zealand white rabbits underwent total ovariectomy to create osteoporosis models, which were verified by measurement of bone mineral density (BMD). The osteoporotic rabbits were randomly divided into two groups. The animals in the enhanced group had pedicle screw placed at L3 after calcium phosphate composited with BMP-2 was injected into the screw trace, while those in the conventional group had the screw inserted at L3 routinely. At 4, 8 and 12 weeks after screw insertion, bone histomorphometry and biomechanical tests were conducted and compared between the two groups. [Results] Compared with that before ovariectomy, the BMD significantly decreased in the animals at 6 months after operation (P＜0.05), which demonstrated a successful osteoporosis model created in rabbits. After pedicle screw placed at L3, the histomorphometric parameters in both group, including area of osteoid tissue, bone-screw interface, bone ingrowth, and bone mineral deposition rate, significantly increased as time went on. The enhanced group proved significantly superior to the conventional group in all histomorphometric parameters at each corresponding time point (P＜0.05). In term of biomechanical tests, the maximal pullout strength and the maximal power dissipation to failure in both groups significantly increased over time. The enhanced group was significantly superior to the conventional group in the two biomechanical parameters at each consistent time point (P＜0.05). [Conclusion] The calcium phosphate composited with bone morphogenetic protein-2 does enhance the stability of pedicle screws placed in osteoporotic vertebral bone, which might be used in the clinical setting.