坐骨重叠征与发育性髋关节脱位手术后再脱位的相关性分析

Correlation between ischium overlap sign and postoperative redislocation of developmental dysplasia of the hip

目的提出坐骨重叠征(ischium overlap sign,IOS)的概念,并分析其与发育性髋关节脱位(developmental dysplasia of the hip,DDH)手术后再脱位的关系。方法回顾性分析2013年9月至2017年5月山东大学附属省立医院治疗的88例(105髋)DDH患儿病例资料,其中男童16例、女童72例;平均年龄12(5~24)个月,平均随访时间34(15~59)个月;双侧17例,左侧63髋,右侧42髋;1髋为髋臼发育不良,11髋半脱位,93髋全脱位。术中行髋关节造影检查,按照Bowen标准选择闭合或切开复位石膏固定术。IOS是指在人类位髋关节造影平片上股骨头软骨内缘与坐骨外缘的重叠关系,二者重叠为Ⅰ度,相接为Ⅱ度,分离为Ⅲ度。将93髋全脱位按照IOS分度进行分组,比较组间再脱位发生率。结果 1髋髋臼发育不良和11髋半脱位者IOS均为Ⅰ度。93髋全脱位中IOSⅠ度14髋,Ⅱ度39髋,此两组均行闭合复位石膏固定,无再脱位病例;Ⅲ度40髋中,闭合复位石膏固定17髋,6髋再脱位;切开复位石膏固定23髋,1髋再脱位。本研究发现Ⅲ度组的再脱位发生率(7/40,17.5%)高于其他两组(P=0.006)。IOS为Ⅲ度的40髋中,闭合复位的再脱位发生率(6/17,35.3%)高于切开复位(1/23,4.4%),差异有统计学意义(X^2=4.518,P=0.034)。结论 IOS与DDH术后再脱位有一定的关系,IOS为Ⅲ度的髋关节如行闭合复位,再脱位的风险较高。

Objective To propose the concept of ischium overlap sign(IOS) and explore its relationship with postoperative redislocation of developmental dysplasia of the hip(DDH).Methods From September 2013 to March 2017,retrospective analysis was performed for clinical data of 88 DDH children(105 hips).There were 16 boys and 72 girls with an average age of 12(5-24) months.The mean follow-up period was 34(15-59) months.The affected side was bilateral(n=17),left(n=63) and right(n=42).The causes were acetabular dysplasia(n=1),subluxation(n=11) and dislocation(n=93).Intraoperative hip arthrography was performed and closed or open reduction selected according to the Bowen’s standard.IOS refers to the relationship of inner edge of femoral head cartilage and outer edge of sciatic bone on hip arthrography in human position.Overlap is grade Ⅰ,converging Ⅱ and separating Ⅲ.Ninety-three dislocated hips were divided into three groups based upon IOS.And the redislocation rates were compared among different groups.Results Acetabular dysplasia(n=1) and subluxation(n=11) belonged to IOS grade I.Among 93 dislocated hips,there were 14 hips of IOS grade I and 39 hips of IOS Ⅱ.Both groups underwent closed reduction plus casting and there was no redislocation.Among 40 hips of IOS Ⅲ,17 hips underwent closed reduction plus casting and 6/17 hips became redislocated.Among 23 hips undergoing open reduction plus casting,one hip was redislocated.The results showed that group of IOS Ⅲ had a higher rate of redislocation(7/40,17.5%) than other groups(P=0.006).In group of IOS Ⅲ,the redislocation rate in children undergoing closed reduction(6/17,35.3%) was statistically higher than those with open reduction(1/23,4.4%)(X^2=4.518,P=0.034).Conclusion A close relationship exists between IOS and postoperative redislocation in DDH.If closed reduction plus casting is performed for DDH of IOS grade Ⅲ,there may be a high redislocation rate.