全髋人工关节置换术后脱位的原因分析及防治

目的　分析全髋人工关节置换（ＴＨＲ） 术后脱位的原因并探讨防治措施。　方法　１９７８～１９９８ 年行ＴＨＲ的患者８５０ 例,其中发生脱位者１５ 例,脱位率约为１－７％ ;其中行２ 次以上手术者１１例,初次手术４ 例。对发生脱位的１５ 例患者的手术情况和脱位原因进行分析。　结果　１５ 例患者中,髋部行２ 次以上手术者１１ 例,均采用后外侧入路,发生后脱位;２ 例采用外侧入路,发生前脱位;２例与假体设计有关,发生髋臼假体金属杯与聚乙烯帽间的脱离。１５ 例患者除１ 例采用闭合复位成功外,其余均切开复位,对假体位置不佳的患者行翻修术,对外展肌肌力弱的患者进行加强修补,或处理大粗隆,以增加外展肌肌力。经随访,均未再发生脱位。　结论　假体置入位置欠佳、两侧软组织不平衡（ 尤其是外展肌的破坏） 是造成ＴＨＲ术后脱位的主要原因;术前仔细评价患者骨盆发育情况,并注意一些骨性标记的变异,术中正确安装假体,仔细清理髋臼周围的骨赘与骨水泥以及注意髋周围软组织的修复,关闭伤口前认真检查手术髋的稳定性,是预防ＨＴＲ术后脱位的有效措施

Analysis and prevention of dislocation after total hip replacement

Objective To analyse and prevent postoperative dislocation after total hip replacement (THR). Methods Of 850 cases operated on by THR 15 (1.7%) had postoperative dislocation. Eleven were revision cases while the other 4 were operated on their primary procedures. Results Postoperative dislocation after THR were found in 15 cases. Eleven cases had posterior dislocation by posterolateral approach after revision of THR. Anterior dislocation occurred in 2 cases who received lateral approach. Another two cases of dislocation were related to the design of prosthesis. Separation of polyethylene liner and metal shell in acetabular prosthesis was noted in the two cases. All the cases but 1 were reduced operatively. The cases with malpositioned prosthesis were revised operatively. Augmentation procedure was carried out to increase the strength of abductor. In one case, relocation of the great trochantor increased the strength of abductor. No redislocation was observed during follow up. Conclusions Postoperative dislocation after THR are due to malpositioning of prosthesis, unbalanced bilateral soft tissues, especially the loosening of abductor. Evaluateing carefully the development of the pelvis and the deviation of normal bone markers is important in addition to accurate insertion and installment of the prosthesis intraoperatively. Complete clearance of osteophytes and bone cements around the acetabulumis reqaired apart from the repairment of adjacent soft tissues. Double check of hip stability should be carried out before the closure of incision.