全髋关节置换术后脱位的原因分析及处理

Causes and managements of dislocation after total hip arthroplasty

[目的]探讨全髋关节置换术后发生脱位的原因、处理及预防方法。[方法]自1996～2004年在本院行全髋关节置换患者共850例,发生置换术后脱位7例,其中男4例,女3例;平均年龄67岁;通过对术前病史、手术入路、术后脱位的时间以及发生脱位的方向进行回顾性研究以探讨脱位的原因、处理以及如何预防。[结果]本组发生全髋关节置换术后脱位7例,其中5例(5/7)为初次全髋关节置换术后脱位,2例(2/7)为翻修手术后脱位;4例(4/7)有既往髋部手术史;1例有脑部手术后精神异常,不配合治疗;脱位方向均为前脱位;所有患者均采用正外侧入路即改良Hardinge入路。髋臼假体外展角2例(2/7)大于55°。发生脱位时间自术后当天至术后27个月,其中5例发生于术后3个月以内。所有7例患者在脱位后均首先给以麻醉下闭合复位、下肢皮牵引6周治疗,其中6例患者获得稳定并未再复发性脱位;1例患者在复位后3个月内又连续2次脱位,并在复位过程中发生髋臼松动,给以手术翻修髋臼调整外展角后获得稳定。[结论]导致全髋关节置换术后脱位的危险因素主要包括髋部手术史、术后患者不能严格按照医嘱进行康复训练、手术入路以及假体位置不良等。对于大多数脱位患者而言,闭合复位以及皮牵引6周是有效的治疗方法,对于复发性脱位的患者在分析脱位原因后可通过翻修手术获得髋关节的稳定。

[Objective] To approach the causes and managements of dislocation after total hip arthroplasty. [ Methods] 850 total hip arthroplasties were done in our department from 1996 to 2004, in which 7 cases experienced post-operative dislocation. Whith 4 males and 3 females, the average age was 67 years old. Causes and managements have been studied retrospectively through analysis of history, surgical approach, timing and direction of the dislocations and predisposing factors of the dislocations occurred. [Results] There wer 7 cases of dislocations of which 5 patients （71%） were primary cases and 2 patients （29%） were revision cases; 4 patients （57%） had history of hip surgery; 1 case had mental disorder after cerebral surgery. Direct lateral approach was used for all these patients, and only anterior dislocation was occurred in this group. Through study the AP X-rays postoperatively, the abduction angle were more than 55 degree in 2 of these cases. The time of dislocation was from right after operation to 27 months after operation; 5 of them experienced their dislocation within 3 months after operation. Closed reduction and 6 weeks traction were selected for all these patients, and 6 of them were successful. Recurrent dislccation occurred twice in another one patient within 3 months after reduction, and the acetabular cup was loosened during closed reduction. A stable joint was achieved after revision and modifying the abduction angle of the cup. [ Conclusion ] Causative risk factors for dislocation after total hip arthroplasty include surgery history on the same hip, inability to comply with instructions of rehabilitation, approach of surgery and malposition of the prosthesis. Closed reduction and traction for 6-week afterwards are usually successful for most of the dislocated cases. Revision could be done in the base of analyzing the reasons for recurrent dislocation, and then stale joint could be achieved.