摘要
目的 探讨聚甲基丙烯酸甲酯 (polymethylmethacrylate,PMMA)骨水泥 ,强化骨质疏松椎弓根螺钉在脊柱内固定术中 ,对不稳定性胸腰椎损伤的即刻稳定性和反复载荷后的稳定性。 方法 6具新鲜女性骨质疏松脊柱标本 (T1 0 ～ L5) ,制备 L1 椎体节段不稳定性损伤模型后椎弓根螺钉系统固定 ,行左 /右侧弯、左 /右旋转和前屈 /后伸 6个方向的稳定性测试 ,并在 MTS 85 8试验机上进行屈 /伸疲劳试验。比较○a正常脊柱 (正常对照组 ) ;○b损伤模型钢板固定疲劳前 (强化前 ) ;○c钢板固定疲劳后 (强化前 ) ;○d钢板固定疲劳前 (强化后 ) ;○e钢板固定疲劳后 (强化后 ) 5种状态下脊柱的稳定性变化。 结果 ○b、○d、○e三种状态下 ,前屈和后伸时的运动角度分别为 6 .2 3± 1.5 6和 4 .4 9± 1.0 0、4 .4 6± 1.83和 6 .6 0± 1.80、 4 .4 1± 0 .82和 4 .4 6± 1.83,运动范围的差异无统计学意义 (P>0 .0 5 ) ,但均小于○a 、○c状态下的运动角度 8.75± 1.88和 1.4 7± 2 .2 5、8.92± 2 .97和 12 .2 4± 3.0 8,有统计学意义 (P<0 .0 1)。 结论 PMMA强化骨质疏松椎弓根螺钉脊柱内固定能明显增强脊柱的稳定性和抗疲劳能力。
Objective To ascertain whether augmentation pedicle screw fixation with polymethylmethacrylate (PMMA) can enhance the stability of unstable thoracolumbar burst fractures of osteoporotic spine. Methods Six fresh frozen female osteoporotic spines (T 10-L 5) were harvested and an anterior and posterior column unstable model of L 1 was made. Each specimen was fixated with plate and the stability test were performed by flexion, extension, axial rotation and lateral bending. The test of fatigue was done with MTS 858.The tests were repeated after screws were augmented with PMMA. To compare the biomechanical stability of 6 different conditions: ○anormal specimens(control), ○b defect model fixed with plate, not augmented and not fatigued, ○cafter fatigued, not augmented, ○dscrews augmented with PMMA, not fatigued, ○eafter augmented and fatigued. Results In ○b, ○d and ○econditions, the ranges of motion(ROM) were 6.23±1.56, 4.49±1.00,4.46±1.83 in flexion and 6.60±1.80,4.41±0.82,4.46±1.83 in extension. There was no significant difference (P>0.05), they were significantly smaller than those in ○a and ○c conditions (8.75±1.88,1.47±2.25 and 8.92±2.97,12.24±3.08) (P<0.01).Conclusion The results demonstrated that augmentation pedicle screws fixation with PMMA can increase the stability of osteoporotic spine.
出处
《中国修复重建外科杂志》
CAS
CSCD
2004年第3期168-170,共3页
Chinese Journal of Reparative and Reconstructive Surgery
基金
广东省自然科学基金 (99B0 670 3G)~~
