Ponseti方法治疗先天性马蹄内翻足侧位X线片距骨跟骨角的特点及对复发的预测价值研究

Characteristics of talus-calcaneus angel on lateral radiograph of congenital clubfoot after Ponseti method and its predictive value for recurrence

目的探究婴幼儿马蹄内翻足经Ponseti方法治疗跟腱松解后早期X线片上距骨跟骨角的特点及其在预测马蹄内翻足复发中的临床价值。方法收集并随访2002年1月至2013年9月广州市妇女儿童医疗中心收治的119例先天性马蹄内翻足患儿,共177足。根据有无复发分为复发组(33例)和未复发组(86例)。患儿初始治疗年龄均小于6个月,均应用Ponseti方法行系列石膏固定矫正足内收内翻后背屈小于15°,并行跟腱松解术。在跟腱松解术后3个月内拍摄足背屈应力下X线侧位片,测量侧位片距骨跟骨角(lateral talus-calcaneus angle,TC_L),对比分析跟腱松解后单侧马蹄足患儿正常足与患足的TC_L特点,分析所有马蹄足TC_L大小与预后的关系,应用logistic回归判断早期TC_L对马蹄内翻足复发的预测价值。结果本研究复发组与未复发组在性别、跟腱松解年龄及跟腱松解术后3个月内X线检查年龄上比较,差别均无统计学意义(P值分别为0.83,0.57,0.17)。TC_L比较,复发组(34.38°±10.99°)与未复发组(40.72°±12.86°)差异有统计学意义(P<0.001)。单侧患儿患足(38.56°±11.57°)与正常足(50.91°±9.26°)比较,差异有统计学意义(P<0.001)。应用Logistics回归计算距骨跟骨角预测马蹄足复发的ROC曲线下面积为0.6629(χ^(2)=8.2567,P=0.0041),距骨跟骨角的最佳临界点为40°。结论先天性马蹄内翻足Ponseti方法治疗、跟腱松解术后3个月内X线片距骨跟骨角明显较正常值小,对预测复发有一定价值。距骨跟骨角越小,复发的可能性越大。

Objective To explore the characteristics of lateral talus-calcaneus angle on early radiographic examination of congenital clubfoot after Ponseti treatment and assess the clinical value of predicting the relapse of clubfoot.Methods Between January 2002 and September 2013,medical records were reviewed for 119 children with congenital clubfoot in 177 feet.They were divided into two groups of non-recurrent and recurrent according to the follow-up outcomes.The age of initial treatment was all under 6 months.Series of cast and achilles tendon release after Ponseti method were employed for correcting the deformity.Early radiographic examination of foot was performed within 3 months after Achilles tendon release.The authors compared lateral talus-calcaneus angle(TC_L)between normal foot and clubfoot in unilateral cases and compared the characteristics of TC_L between non-recurrent and recurrent cases.Also the relationship was examined between TC_L and prognosis of clubfoot for determining the value of initial TC_L in predicting the recurrence of clubfoot.Results No significant difference existed in gender,age of Achilles tendon release and age of radiographic examination(P=0.83,P=0.57,P=0.17).TC_L of initial radiographic examination differed markedly between two groups[(34.38±10.99°)vs.(40.72±12.86°),P<0.001].TC_L was significantly different between clubfoot and normal foot[(38.56±11.57°)vs.(50.91±9.26°),P<0.001].Logistic regression indicated that the area under the curve of receiver operating characteristic(ROC)was 0.6629(χ^(2)=8.2567,P=0.0041)in predicting recurrence of clubfoot using a TC_L.cutoff value of 40°.The diagnostic specificity and sensitivity was 61.11%and 68.09%respectively.Conclusion TC_L on early radiography within 3 months after achilles tendon release is less than that in normal foot.TC_L offers some values in the prediction of recurrence after treatment.The smaller TC_L,the more likely to be relapsing with a cutoff value of 40°.