PMMA提高椎体钉固定强度的体外实验研究  

Polymethylmethacrylate on enhancing the strenght of vertebral body screw fixation

作　　者：孙雁宇[1] 郭艳幸[1] 赵庆安[1] 刘忠国[2] 

机构地区：[1]厦门市第二医院,福建361021 [2]厦门市第三医院,福建361100

出　　处：《中国矫形外科杂志》2005年第24期1883-1885,共3页Orthopedic Journal of China

摘　　要：[目的]探讨骨水泥(PMMA)强化后椎体钉穿透单侧椎体固定的可行性。[方法]选用新鲜成人尸体标本32个,按骨密度分为骨质正常组和骨质疏松组分别进行实验。实验组为骨水泥(PMMA)强化后椎体钉穿单侧椎体皮质固定;对照组为无骨水泥强化,椎体钉穿透双侧椎体皮质固定。应用螺钉拔出实验,记录螺钉最大拔出力。[结果]在骨质正常组中,PMMA组和对照组拉出力分别为1758.42±32.63N和843.25±65.35N,增加109%±33%。在骨质疏松组中,PMMA组和对照组拉出力分别为811.19±188.58N和374.21±77.66N,增加122%±56%。差异有显著性P<0.01。[结论]应用PMMA固化椎体钉,减少手术并发症是可行的。[ Objective] To determine if a polymethymethacrylate（PMMA） provides a feasible and secure augmentation of anterior unicortical vertebral screw fixation. [ Method] Thirty-two fresh the thoracic and lumbar vertebral were obtained form four human cadavers. All specimens were divided into two groups depending on bone mineral density（BMD） ：osteoporosis and normal bone density. Then the specimens were randomly divided into two disposing groups： intact control （bicortical screw） （n = 8） and PMMA late augmentation（ unicortical screw） （n = 8）. Esch disposing group included four thoracic vertebrae （T9 - T12 ）and four lumbar vertebrae （L1-4）. Each specimen then was tested to failure in axial pullout using an MTS（ Minnesota Testing systems）. Pullout strength was defined as the load before a marked decrease in the load-deflection curve. [ Result] In normal bone density group, the screw pullout strengths for the uncritical screw augmented by PMMA wcrc 1758.44 ± 232.63 N,thc pullout strengths for thc unicortical strengths for the bicortical screw without any augmentation were 374.21 ± 77.66 N. The unicortical screw augmented by PMMA group was 122% ±56% stronger than the control group（ biocortical screw）. [ Conclusion] This study demonstrated that a vertebral body unicortical screw augmented by a bidegradable PMMA may avoid the potential problems associated with the use of bicortical acrew.

关 键 词：磷酸钙骨水泥 骨螺丝 生物力学 

分 类 号：R687.3[医药卫生—骨科学]