发育性髋关节发育不良患者脊柱-骨盆冠状位序列的变化

Changes in coronal spino-pelvis alignment in patients with developmental hip dysplasia

目的探讨发育性髋关节发育不良(developmental dysplasia of the hip,DDH)患者脊柱-骨盆冠状位序列的变化规律以及全髋关节置换术对冠状位脊柱-骨盆序列的影响。方法纳入临床资料完整的DDH患者48例,男6例、女42例;年龄(42.81±10.42)岁(范围22~61岁)。双侧髋发育不良11例,单侧髋发育不良37例,共59髋。Crowe分型Ⅰ型13髋、Ⅱ型7髋、Ⅲ型4髋、Ⅳ型35髋。于术前和末次随访时摄站立位脊柱全长正位X线片及站立位下肢全长正位X线片,测量脊柱-骨盆冠状位参数:Cobb角、冠状位平衡、骶骨倾斜角、髂骨倾斜角、髋关节倾斜角、L5倾斜角、下肢长度。分析冠状位脊柱-骨盆参数之间的相关性,评估数据测量的可重复性。结果随访时间(10.31±2.62)个月(范围3~18个月)。DDH患者术前髂骨倾斜角、骶骨倾斜角、髋关节倾斜角和L5倾斜角的观察者内复测信度分别为0.965、0.875、0.912和0.934,观察者间信度分别为0.887、0.889、0.892和0.907。33例DDH患者存在双下肢不等长,发生率为69%(33/48);28例患者伴有脊柱侧凸,发生率为58%(28/48);发生髋关节脱位43例,其中37例股骨头相对位置较高一侧(即脱位侧)的骨盆位置更低,发生率86%(37/43);发生骨盆倾斜46例,发生率为96%(46/48)。全髋关节置换术后髂骨倾斜角由术前6.71°±4.62°降低至3.52°±3.14°,差异有统计学意义(t=4.81,P<0.001);骶骨倾斜角由术前6.38°±5.48°降低至3.72°±3.38°,差异有统计学意义(t=3.91,P<0.001);术前髋关节倾斜角为5.32°±5.83°、术后为3.71°±3.62°,差异无统计学意义(t=1.85,P=0.071);L5倾斜角由术前6.12°±5.46°降低至4.33°±4.71°,差异有统计学意义(t=2.15,P=0.037);Cobb角由术前11.05°±10.76°降低至6.82°±7.76°,差异有统计学意义(t=4.07,P<0.001);术前冠状位平衡为(14.22±10.64)mm、术后为(13.73±12.58)mm,差异无统计学意义(t=0.24,P=0.821)。Cobb角与骶骨倾斜角、髂骨倾斜角均呈正相关(r=0.61,P<0.001;r=0.57,P<0.001)。结论DDH患者出现骨盆冠状位倾斜的原因包括双下肢不等长与髋关节脱位。冠状位骨盆倾斜导致代偿性脊柱侧凸,使整体冠状位脊柱-骨盆序列发生改变,但仍能保持冠状位平衡。全髋关节置换术能够显著改善DDH患者冠状位骨盆倾斜以及代偿性侧凸的程度。

Objective To investigate the changes in coronal spino-pelvis alignment in patients with developmental dysplasia of the hip(DDH)and effects of total hip arthroplasty on it.Methods This study included 48 patients(6 males and 42 females)with DDH who underwent total hip arthroplasty from January 2009 to December 2019 at the Department of Orthopaedics,the PLA General Hospital.The average age of patients was 42.81±10.42 years(range,22 to 61 years),whose follow-up time was 10.31±2.62 months(range,3 to 18 months).Eleven cases underwent bilateral hip replacements and 37 cases underwent unilateral hip replacements,which included 13 hips in Crowe I,7 hips in II,4 hips in III,35 hips in IV.The coronal spino-pelvic parameters were measured with all patients,including Cobb angle,coronal balance distance(CBD),sacral obliquity(SO),iliac obliquity(IO),hip obliquity(HO),L5 obliquity(L5O)and leg length.Results The interobserver reliability of IO,SO,HO and L5O in patients with DDH was 0.965,0.875,0.912 and 0.934.The interobserver reliability of IO,SO,HO and L5O was 0.887,0.889,0.892 and 0.907.Thirty-three patients diagnosed with DDH had leg length discrepancy,which the incidence was 69%(33/48).The incidence of scoliosis of patients was 58%(28/48).The incidence of pelvic obliquity was 96%(46/48).The preoperative IO was 6.71°±4.62°and the postoperative IO was 3.52°±3.14°,the difference was statistically significant(t=4.81,P<0.001).The preoperative SO was 6.38°±5.48°and the postoperative SO was 3.72°±3.38°,the difference was statistically significant(t=3.91,P<0.001).The preoperative HO was 5.32°±5.83°and the postoperative HO was 3.71°±3.62°,the difference had not statistically significant(t=1.85,P=0.071).The preoperative L5O was 6.12°±5.46°and the postoperative L5O was 4.33°±4.71°,the difference had statistically significant(t=2.15,P=0.037).The preoperative Cobb angle was 11.05°±10.76°and the postoperative Cobb angle was 6.82°±7.76°,which had a statistically difference(t=4.07,P=0.001).There is no significant difference of preoperative CBD and postoperative CBD,which was 14.22±10.64 mm vs.13.73±12.58 mm(t=0.24,P=0.821).Cobb angle was positively correlated with SO and IO(r=0.61,P<0.001;r=0.57,P<0.001).Conclusion Causes coronal pelvic obliquity in patients with DDH included leg length discrepancy and hip dislocation.Coronal pelvic obliquity can lead to compensatory scoliosis,which alters the overall coronal spino-pelvic alignment of patients with DDH.However,they can still maintain coronal balance.Total hip arthroplasty could improve the degree of coronal pelvic obliquity significantly and compensatory scoliosis in patients with DDH.