内锁髓内钉和外固定架治疗胫腓骨骨折的临床和生物力学比较

Clinical and biomechanical comparison of tibia factures treated by external fixator and tibial intramedullary interlocking nail

目的：通过非扩髓型胫骨内锁髓内钉和旋转加压式外固定架的生物力学分析及两者治疗的骨折的回顾性随访，比较两者生物力学的特性和临床适应证的选择．方法：用尸体胫腓骨5对，造成中段斜形骨折，随机用内锁髓内钉和外固定架固定，在WJ－10A试验机上测试．同时对用其治疗的44例患者进行随访，平均随访时间13mo．结果：外固定架承受的平均最大破坏载荷（MLF）为2130N，内锁髓内钉为2275N，两者无显著性差异（P＞0．05）．临床随访发现两组患者在手术时间，X线暴光时间以及输血量等方面存在着显著差异（P＜0．01），但在骨愈合时间，不扶拐行走时间以及膝踝关节功能等方面并无差异．结论：两者都具有手术不剥离骨膜，骨折固定牢靠，关节功能影响小的优点，外固定架多用于开放性骨折，对胜骨骨干或干骺端的骨折都适合，内锁髓内钉多用于闭合性骨折，只适合腔骨骨干的骨折．胫骨节段性骨折和骨不连应首选胫骨内锁髓内钉．

Aim: Through the biomechanical analysis andclinically retrospective follow-up of the patients treated ei-ther by unreamed inter-locking intramedullary nail of tibiaor rotating external fixator of tibia, the authors aimed atcomparing their biomechanical properties and the options ofclinical indications. Methods: An unstable fracture modelwas developed in 10 cadaver tibias in which either unreamedinterlocking intramedullary nail of tibia or rotating externalfixator of tibia was applied randomly to fix the models. Themodels were then tested on the WJ-10A Universal TestingSystem. A total of 44 tibia fractures treated by both deviceswere followed up with an average duration of 13 months.Results: The maximum loading to failure (MLF) of fixatorgroup was 2130 N, while that of nail group was 2275 N,and no significant differences were found between themthrough test (P > 0. 05 ). The clinical follow-up revealedthat the significant differences really existed between themin terms of operating time, X-ray exposure time as well asintraoperative blood transfusions (P<0.01), while no sig-nificant differences were found in terms of bone healingtime, weight bearing time and knee-ankle joint function.Conclusion: Both devices are considered much more effective in the treatment of tibia fracture. The unreamed inter-locking intramedullary nail of tibia should be the first choiceof the treatment of non-union and malunion of tibia fractures.