成人发育性髋关节脱位全髋关节置换术后膝外翻的相关因素

Factors related to knee valgus after total hip arthroplasty for developmental hip dislocation in adult

摘要:

[目的]探讨 Hartofilakids III 型发育性髋关节发育不良全髋关节置换（total hip arthroplasty, THA）术后患侧出现膝外翻的影响因素。[方法] 回顾性分析 2003—2013 年本科采用 THA 治疗 Hartofilakids III 发育性髋关节发育不良 50 患者 （62 髋） 的临床资料。按照 Ranawat 等和 Elkus 等的标准，股胫角（femorotibial angle, FTA）＞10°时为膝外翻，观察术后膝外翻的发生情况。采用单因素比较和多元逻辑回归分析探索术后膝外翻发生的相关因素。[结果]62 髋共发生膝外翻 23 髋，占比 37.1%。是否发生膝外翻两组在性别、年龄、BMI、术前及末次随访的 Harris 髋评分、术前 AKS 膝评分、术前胫骨近端内侧角（medial proxi- mal tibial angle, MPTA）、髂胫束松解、术后髋关节脱位及翻修的差异均无统计学意义 （P＞0.05）。外翻组末次随访 AKS 膝评分 [(65.1±9.5) 分 vs (74.1±5.8) 分, P＜0.001]、术前 [(83.2±5.1)° vs (87.9±2.9)°, P＜0.001] 与末次随访的 [(77.1±4.4)° vs (82.6±2.6)°, P＜ 0.001] 外侧股骨远端机械角 （mechanical lateral distal femoral angle, mLDFA）均显著小于未外翻组；而前者的术前 FTA [(9.9±5.2)° vs (3.6±2.8)°, P＜0.001] 与末次随访的 FTA [(17.2±3.7)° vs (6.8±3.3)°, P＜0.001] 以及末次随访的 MPTA [(87.2±4.3)° vs (84.4±3.1)°, P= 0.010] 均显著大于后者。外翻组短缩截骨占比 [髋, 是/否, (19/4) vs (33/68) , P=0.014] 显著高于未外翻组，而其短缩长度 [(1.6±0.5) cm vs (2.1±0.9) cm, P=0.004] 显著小于未外翻组。多因素逻辑回归分析显示，术前较大的 FTA（OR=1.654, P＜0.05）和 mLDFA（OR= 1.221, P＜0.05）是术后膝外翻发生的独立危险因素。[结论]成人高位 DDH 病例 THA 术后存在发生膝外翻的风险，THA 截骨与髂胫束松解可以降低其发生率。术前较大的 FTA 与 mLDFA 是患者术后是否发生膝外翻的危险因素。

Abstract:

[Objective] To explore the factors related to genu valgus (GV) of the affected side after total hip arthroplasty (THA) for Harto- filakids type III developmental dysplasia of the hip in adult. [Methods] A retrospective study was performed on 62 patients who received THA for Hartofilakids type III developmental dysplasia in our department from 2003 to 2013. According to Ranawat and Elkus et al.' s criteria, the GV was defined as the femorotibial angle (FTA) more than 10° at the latest follow-up. Univariate comparison and multiple logistic regression analysis were used to explore the related factors of postoperative GV. [Results] A total of 23 patients were determined as GV at the latest follow-up, accounting for 37.1%. There were no significant differences between the two groups in terms of gender, age, BMI, Harris score before and at the last follow-up, AKS score before surgery and medial proximal tibial angle (MPTA) before surgery, as well as the ratio of intraoperative iliotibial band release, incidence of hip dislocation and revision surgery during the followup (P＞0.05). The GV group proved significantly lower than the non-GV group in terms of AKS score at the latest follow-up [(65.1±9.5) vs (74.1±5.8), P＜0.001], mechanical lateral distal femoral angle (mLDFA) [(83.2±5.1)° vs (87.9±2.9)°, P＜0.001] preoperatively and [(77.1±4.4)° vs (82.6±2.6)°, P＜0.001] at the last follow-up, whereas the former was significantly greater than the latter in terms of FTA [(9.9±5.2)° vs (3.6±2.8)°, P＜0.001] preoperatively and [(17.2±3.7)° vs (6.8±3.3)°, P＜0.001] at the last follow-up, as well as MPTA [(87.2±4.3)° vs (84.4±3.1)°, P=0.010] at the last follow-up. In addition, the GV group was significantly higher in ratio of shortening osteotomy during THA [hip, yes/no, (19/4) vs (33/68), P= 0.014], while significantly less shortening length [(1.6±0.5) cm vs (2.1±0.9) cm, P=0.004] than the non-GV group. As results of multivariate logistic regression, the greater preoperative FTA (OR=1.654, P＜0.05) and preoperative mLDFA (OR=1.221, P＜0.05) were independent risk factors for postoperative GV. [Conclusion] There is a high risk of genu valgus after THA for high DDH in adult, despite of the fact that shortening osteotomy and iliotibial band release can alleviate it. The greater preoperative FTA and mLDFA are risk factors for postoperative genu valgus