发育性髋关节发育不良闭合复位术失败影响因素的MR评价

MR evaluation of the failure factors of closed reduction in developmental dysplasia of the hip

目的:通过MRI评估发育性髋关节发育不良(DDH)患儿闭合复位术结果 ,探讨哪些因素会导致复位失败。方法:连续收集85例行闭合复位术并石膏裤外固定治疗的DDH患儿,术后均行常规核磁扫描,在冠状面图像上测量软骨性臼头指数(CAHI),以此为标准分为闭合复位成功组与失败组。分别测量两组患儿的骨性髋臼指数(BAI)、软骨性髋臼指数(CAI)、中心边缘角(CE角)、软骨性中心边缘角(CCE角),并观察髋臼软骨、盂唇、圆韧带的情况。比较组间BAI、CAI、CE角、CCE角以及髋臼软骨内出现高信号区、盂唇肥大及内翻、圆韧带延长肥厚的概率是否有差异性。结果:两组间BAI、CAI值无明显统计学差异(均P>0.05);失败组CE角、CCE角明显小于成功组(均P<0.05),髋臼软骨内出现高信号区、盂唇肥大内翻、圆韧带延长肥厚的概率明显高于成功组(均P<0.05)。结论:CE(CCE)角可以作为判断闭合复位术是否成功的重要指标,髋臼软骨内高信号区的出现、盂唇肥大内翻、圆韧带延长肥厚会导致治疗效果不满意。

Objective： To evaluate the results of closed reduction in developmental dysplasia of the hip （DDH） by MRI, and to explore the factors which lead to the failure of closed reduction. Methods： Consecutive 85 children with DDH treated by closed reduction and plaster external fixation were enrolled~ After reduction, all children underwent conventional MRI scan. The cartilage acetabular index （CAHI） was measured in the coronal image, then all children were divided into a successful group and a failure group after closed reduction. Two groups of patients were measured the bony acetabular index（BAI）, carti- laginous aeetabular index （CAI）, center edge angle （CE angle）, cartilaginous center edge angle （CCE angle）, and the acetabular cartilage, labrum and round ligament were observed. The differences of the value of BAI, CAI, CE angle, CCE angle and the probability of high signal area in acetabular cartilage, labrum hypertrophy and varus, round ligament hypertrophy were com- pared between two groups. Results： There was no significant difference between the two groups in BA[ or CAI（P〉0.05）. In the failure group, CE and CCE angles were significantly lesser than those of successful group（P〈0.05）. The probability of high sig- nal area in acetabular cartilage, labrum hypertrophy and varus, round ligament hypertrophy was significantly higher than that of the successful group. Conclusions： CE （CCE） angle can be used as the important indicator to evaluate ch）sed reduction. High signal area in acetabular cartilage, labrum hypertrophy and varus, round ligament elongation and hypertrophy will lead to unsatisfactory treatment effect.