[Effects of femoral offset and mechanical axis of the lower extremity on hip after osteotomy for adult developmental dysplasia of the hip].

To investigate the effects of femoral offset and mechanical axis of the lower extremity on hip after osteotomy for adult developmental dysplasia of the hip (DDH).A clinical data of 62 adult patients with DDH (62 hips), who underwent periacetabular osteotomy combined with femoral osteotomy between January 2016 and May 2019 and met selective criteria, was retrospectively analyzed. There were 6 males and 56 females. The age ranged from 18 to 38 years, with an average of 24.4 years. Body mass index ranged from 15.8 to 31.8 kg/m 2, with an average of 21.8 kg/m 2. There were 44 cases of Hartofilakidis typeⅠ and 18 cases of typeⅡ. According to the modified Tönnis osteoarthritis staging, 46 cases were stage 0 and 16 cases were stageⅠ. There were 13 cases with pelvic anteversion, 40 cases with normal pelvis, and 9 cases with pelvic retroversion. Intraoperative blood loss, length of hospital stay, and complications were recorded. Postoperative hip function was evaluated by Harris score and International Hip Outcome Tool (iHOT) score. The femoral offset, collo-diaphyseal angle, hip-knee-ankle angle (HKA), knee valus angle, CE (Wiberg central-edge angle), anterior CE angle, and acetabular index angle were measured and the osteotomy healing was observed on X-ray films. Patients were grouped according to postoperative femoral offset (≥48 mm or <48 mm) and HKA [varus group (HKA<177°), normal group (HKA 177°-183°), and valgus group (HKA>183°)]. Harris score and iHOT score were compared between groups.Intraoperative blood loss ranged from 200 to 1 550 mL, with an average of 476 mL. The length of hospital stay ranged from 8 to 21 days, with an average of 13.3 days. All incisions healed by first intention. All patients were followed up 2.0-4.5 years, with an average of 2.8 years. At 1 year after operation, the Harris score and iHOT score of the hip joint significantly increased when compared with those before operation ( P<0.05); there were significant differences in the femoral offset, collo-diaphyseal angle, HKA, knee valus angle, CE angle, anterior CE angle, and acetabular index angle between pre- and post-operation ( P>0.05). According to the modified Tönnis osteoarthritis staging, 38 cases were stage 0 and 24 cases were stageⅠ; and there was no significant difference between pre- and post-operation ( χ2=2.362, P=0.124). There were 11 cases with pelvic anteversion, 38 cases with normal pelvis, and 13 cases with pelvic retroversion, showing no significant difference when compared with that before operation ( χ2=0.954, P=0.623). The pubic branch osteotomy did not heal in 9 cases, proximal femur osteotomy did not heal in 2 cases, and inferior pubic ramus stress fracture occurred in 5 cases. There were significant differences ( P<0.05) in the Harris score and iHOT score between femoral offset≥48 mm group ( n=10) and femoral offset<48 mm group ( n=52). There was no significant difference ( P>0.05) in Harris score and iHOT score between varus group ( n=13), normal group ( n=40), and valgus group ( n=9).Periacetabular osteotomy combined with femoral osteotomy can improve the femoral offset and mechanical axis of the lower extremity of patients with DDH, and improve the functional score of the hip. However, excessive increase of femoral offset during femoral osteotomy is not desirable, resulting in low postoperative functional score.探讨成人发育性髋关节发育不良（developmental dysplasia of the hip，DDH）截骨矫形术后，股骨偏心距、下肢力线改变对髋关节功能的影响。.回顾分析2016年1月—2019年5月，接受髋臼周围截骨术联合股骨近端截骨术治疗并符合选择标准的62例（62髋）成年DDH患者临床资料。男6例，女56例；年龄18～38岁，平均24.4岁。身体质量指数15.8～31.8 kg/m 2，平均21.8 kg/m 2。Hartofilakidis分型：Ⅰ型44例，Ⅱ型18例。改良 Tönnis 骨关节炎分期：0期46例，Ⅰ期16例。骨盆前倾13例，正常40例，后倾9例。记录术中失血量、住院时间以及并发症发生情况；采用Harris评分和国际髋关节评分（iHOT）评价临床疗效；于X线片测量颈干角、股骨偏心距、髋-膝-踝角（hip-knee-ankle angle，HKA）、膝外翻角、外侧CE角（Wiberg central-edge angle）、前CE角、臼顶倾斜角，观察截骨愈合情况。将患者根据术后偏心距分为≥48 mm组、<48 mm组，以及根据HKA分为膝内翻组（HKA<177°）、力线正常组（HKA 177°～183°）和膝外翻组（HKA>183°），进行组间功能评分比较。.术中失血量200～1 550 mL，平均476 mL。住院时间8～21 d，平均13.3 d。术后切口均Ⅰ期愈合。62例患者均获随访，随访时间2.0～4.5年，平均2.8年。术后1年，髋关节Harris评分、iHOT评分均较术前增加，差异有统计学意义（ P<0.05）；影像学复查显示颈干角、股骨偏心距、HKA、膝外翻角、外侧CE角、前CE角以及臼顶倾斜角与术前比较，差异均有统计学意义（ P<0.05）。改良 Tönnis 骨关节炎分期0期38例、Ⅰ期24例，与术前比较差异无统计学意义（ χ2=2.362， P=0.124）。骨盆前倾11例、正常38例、后倾13例，与术前比较差异无统计学意义（ χ2=0.954， P=0.623）。术后发生耻骨支截骨未愈合9例、股骨近端截骨未愈合2例，耻骨下支应力骨折5例。62例患者中，股骨偏心距≥48 mm组10例、<48 mm组52例，组间Harris评分及iHOT评分差异均有统计学意义（ P<0.05）；膝内翻组13例、力线正常组40例、膝外翻组9例，组间Harris评分及iHOT评分差异均无统计学意义（ P>0.05）。.髋臼周围截骨术联合股骨近端截骨术能改善DDH患者股骨偏心距和下肢力线，提高髋关节术后功能评分。但是股骨侧截骨时不宜过度增加股骨偏心距，以免影响髋关节功能恢复。.