胸腰椎骨折内固定术后椎弓根螺钉断裂原因的探讨

Causes of pedicle screw breakage after internal fixation for thoracolumbar fracture

目的探讨胸腰段骨折椎弓根螺钉系统内固定后,椎弓根螺钉断裂的原因。方法对2012年4月‐2013年4月应用椎弓根螺钉内固定系统治疗的胸腰段骨折268例进行分析。结果经过0.5~2.0年的随访,出现螺钉断裂18例,其平均发生时间为术后17.7个月,11例在取出内固定物前复查X线片时发现。断钉率：后侧植骨组（5/59）与未植骨组（6/71）高于后外侧植骨（7/138）（P〈0.05）;爆裂型骨折患者（7/73）显著高于压缩型骨折（8/144）和骨折脱位型患者（3/51）（P〈0.05）;未使用横杆组（10/113）显著高于使用横杆组（8/155）（P〈0.05）;术后内固定物超过1年取出组（11/98）显著高于0.5~1年间取出组（7/170）（P〈0.05）。结论发现椎弓根螺钉断裂或松动的主要原因有：1植骨融合不当;2手术适应证及手术方式选择不当;3未正确使用横连杆;4内固定物取出过迟;5术后未佩戴支具或支具佩戴时间过短;6术者的操作不恰当。术中有效严格的植骨融合,选择合理的手术方式,掌握其适应证,合理使用横连杆,适当时间取出内置物及术后常规佩戴支具,提高术者的操作技术等都可以有效防止椎弓根螺钉断裂的出现。

【Objective】To determine the causes of pedicle screw breakage after internal fixation for thoracolumbar fracture.【Methods】Totally 268 cases of thoracolumbar fractures treated by pedicle screw internal fixation from April 2012 to April 2013 were analyzed.【Results】After 0.5 to 2 years of follow-up, there was 18 cases of screw breakage, the average occurrence time was 17.7 months after surgery, and 11 cases were found after reviewing X-ray before the removal of internal fixations. The nail breaking rate of posterior bone graft group（5/59） and no bone graft group（6/71） was higher than that of posterolateral fusion group（7/138）（P 〈0.05）; the nail breaking rate of burst fracture group（7/73） was higher than that of the compression fracture group（8/144） and fracture and dislocation group（3/51）（P〈 0.05）; the nail breaking rate of the group without using bar（10/113） was higher than that of the group using bar（8/155）（P〈 0.05）; the nail breaking rate of the group of removing internal fixations more than 1 year（11/98） was higher than that of the group of removing internal fixations between 0.5 and 1 year（7/170）（P 〈0.05）.【Conclusion】The main reasons for the fracture of pedicle screw were： 1 the fusion of bone graft was improper; 2 the selection of surgical indications and surgical approach was not appropriate; 3 the cross bar was not used correctly; 4 the internal fixator was taken out too late; 5 after the operation, the patients did not wear a brace or the time of wearing a brace was too short; 6 the operator＇s operation was not appropriate. Effective and strict bone graft fusion, choice of reasonable surgical operation method, grasping the indications, using cross bar rationally, taking out the built-in object at appropriate time, wearing braces after the operation and improvements of operational technology can play a role in preventing the fracture of pedicle of vertebral arch.