交锁髓内钉断裂的原因分析及对策

探讨交锁髓内钉断裂的原因，提出预防的对策。方法：从１９９２年至１９９７年，对６４例复杂粉碎性股骨骨折作了交锁髓内钉固定。结果：５５例随访，平均２６个月。共发生４例交锁钉断裂，断钉率为６．３％。断钉发生在术后６～１４月，３例位于骨折远端第１枚横锁螺孔处，１例位于交锁钉中段。结论：作者认为断钉原因有：开放穿钉，过度分离骨膜，过早负重及功能锻炼不合适等。另外，股骨远端第１枚横锁螺钉离骨折端太近，应力集中。预防断裂的方法有尽量闭合穿钉，选择较粗较长的交锁钉，交锁螺钉应稍远离骨折端，避免过早负重及合适的功能锻炼等。

Biomechanical Analysis and Prevention of the Failure of the Interlocking Nail

Objective:To evaluate the reason of failure of the interlocking nail,and indicate the methods of prevention.Methods:From 1992 to 1997,64 patients with complex femur fractures were treated with the interlocking nail.Results:55 cases were followed up for average 26 months.There were 4 breakages in the locking nails.The percentage of failure is 6 3%.The failure occurred after operation from 6 to 14 months.And 3 cases were at the first screw of the distal of the fracture,1 case at the middle of the nail.Conclusion:The reasons of breakage concluded open operation,too much separation of the periosteum,too early full weight bearing and unfit function exercise.Besides ,the distal first screw was too close to the fracture site,where the stress was most concentrated.The prevention of failure involves closed interlocking,using the more long and thicker nail.The distal first screw is more distal to fracture site,and the patient avoids early full weight bearing and exercise with the fitted method.