Wek Caesar, Chowdhury Piyal, Smith Christian, Kokkinakis Michail
Evelina London Children's Hospital, London, UK.
King's College London University, London, UK.
J Child Orthop. 2020 Oct 1;14(5):397-404. doi: 10.1302/1863-2548.14.200008.
Reimers migration percentage (MP) is the gold standard for measuring hip displacement in children with cerebral palsy (CP). Hip surveillance registries proposed using the top of the Gothic arch (GA) as a modification in patients with acetabular dysplasia because the classical method (CM) described by Reimers may underestimate hip migration. The aim of this study is to assess the inter- and intra-observer reliability of the modified method (MM) versus the CM and identify their effect on the MP.
We performed a retrospective review of 50 children with CP, who had a hip radiograph at our institution between 1st April 2014 and 28th February 2018. All hip radiographs were carefully selected to show the presence of a GA. Four observers measured the MP using the CM and MM for each patient. Interclass coefficient was used to estimate inter- and intra-observer reliability.
Inter-observer reliability was excellent for the CM with ICC 0.96 (95% CI 0.94 to 0.97) and good for the MM, ICC 0.78 (95% CI 0.51 to 0.89) p < 0.001. Intra-observer reliability was excellent for both methods raging from ICC 0.94 to 0.99 for the CM and ICC 0.89 to 0.95 for the MM. The mean MP was 19% for the CM and 28% for the MM (p < 0.001).
The CM is more reliable than the MM to measure hip migration in children with CP. If the CM is used and acetabular dysplasia with a GA are present on the hip radiograph, then a 9% hip migration underestimation should be considered on decisions for both referral and surgical management.
II.
赖默斯移位百分比（MP）是测量脑瘫（CP）患儿髋关节移位的金标准。髋关节监测登记处建议，对于髋臼发育不良的患者，使用哥特弓（GA）顶部作为一种改进方法，因为赖默斯描述的经典方法（CM）可能会低估髋关节移位。本研究的目的是评估改良方法（MM）与CM之间的观察者间和观察者内可靠性，并确定它们对MP的影响。
我们对50例CP患儿进行了回顾性研究，这些患儿在2014年4月1日至2018年2月28日期间在我们机构进行了髋关节X线检查。所有髋关节X线片均经过仔细挑选以显示GA的存在。四名观察者对每位患者使用CM和MM测量MP。组内相关系数用于估计观察者间和观察者内可靠性。
CM的观察者间可靠性极佳，ICC为0.96（95%CI 0.94至0.97），MM的观察者间可靠性良好，ICC为0.78（95%CI 0.51至0.89），p<0.001。两种方法的观察者内可靠性均极佳，CM的ICC范围为0.94至0.99，MM的ICC范围为0.89至0.95。CM的平均MP为19%，MM的平均MP为28%（p<0.001）。
在测量CP患儿的髋关节移位时，CM比MM更可靠。如果使用CM且髋关节X线片上存在伴有GA的髋臼发育不良，则在转诊和手术管理决策时应考虑髋关节移位低估9%的情况。
II级。
