Gillette Children's Specialty Healthcare, Saint Paul.
Department of Rehabilitation Medicine, University of Minnesota.
J Pediatr Orthop. 2023 Jan 1;43(1):31-36. doi: 10.1097/BPO.0000000000002264. Epub 2022 Sep 12.
Restricted weight bearing is commonly prescribed in Legg-Calvé-Perthes Disease (LCPD), raising concerns of causing overweight or obesity. This study utilizes prospectively collected data to address the following questions: (1) does body mass index (BMI) Z-score increase over the course of LCPD follow-up; (2) is having a BMI category of normal, overweight, or obese at baseline associated with BMI Z-score changes over the course of follow-up; and (3) is the duration of weight bearing restrictions (no restrictions, <3, 3 to <6, 6 to 9, or >9 mo) associated with BMI Z-score changes.
Data of 130 children aged 5 to 12 years with unilateral early-stage LCPD were extracted from an international database. Nation-specific BMI Z-scores and percentile-based weight categories were determined, and the duration of follow-up and weight bearing restrictions were calculated. Longitudinal changes in BMI Z-scores were evaluated for the 3 study questions using mixed effects linear regression models with surgery as a covariate. Sensitivity analyses were used to determine the influence of socio-cultural background (USA vs. India) for each study question.
During the 35.5±15.9 months of follow-up, no statistically significant increase in BMI Z-scores was observed across the entire cohort, or following stratification by baseline weight categories or the duration of the weight bearing restriction. Sensitivity analyses indicated that patients in the USA had no change in their BMI Z-score. When stratified by weight categories, the normal weight of US children had a small increase in their BMI Z-score (0.005 per mo, 95% confidence interval: 0.0002, 0.009), but this was not seen in other BMI categories. The cohort of Indian children had a small but significant decrease in their BMI Z-score (-0.005/mo, 95% CI: -0.009, -0.0002). After stratification by weight categories, a small decrease of the BMI Z-score was observed only in the Indian overweight children (-0.016 per mo, 95% CI: -0.027, -0.005) and no other BMI category.
Weightbearing restrictions over the course of follow-up for our cohort of children with early-stage LCPD were not associated with clinically meaningful increases of BMI Z-scores. Weight gain is multi-factorial and probably not caused by weight bearing restrictions alone.
III Diagnostic Study.
在 Legg-Calvé-Perthes 病（LCPD）中，通常会限制负重，这引发了超重或肥胖的担忧。本研究利用前瞻性收集的数据来解决以下问题：（1）在 LCPD 随访过程中，体重指数（BMI）Z 评分是否会增加；（2）在基线时BMI 类别为正常、超重或肥胖是否与随访过程中的 BMI Z 评分变化相关；（3）负重限制的持续时间（无限制、<3 个月、3-<6 个月、6-9 个月、>9 个月）是否与 BMI Z 评分变化相关。
从一个国际数据库中提取了 130 名 5 至 12 岁单侧早期 LCPD 儿童的数据。确定了特定国家的 BMI Z 评分和基于百分位的体重类别，并计算了随访时间和负重限制时间。使用混合效应线性回归模型，以手术为协变量，评估了 3 个研究问题中 BMI Z 评分的纵向变化。使用敏感性分析确定了每个研究问题中社会文化背景（美国与印度）的影响。
在 35.5±15.9 个月的随访期间，整个队列或按基线体重类别或负重限制时间分层后，BMI Z 评分均无统计学显著增加。敏感性分析表明，美国患者的 BMI Z 评分没有变化。按体重类别分层时，美国正常体重儿童的 BMI Z 评分略有增加（每月增加 0.005，95%置信区间：0.0002，0.009），但其他 BMI 类别则未见此现象。印度儿童队列的 BMI Z 评分略有显著下降（每月减少 0.005，95%置信区间：-0.009，-0.0002）。按体重类别分层后，仅在印度超重儿童中观察到 BMI Z 评分略有下降（每月减少 0.016，95%置信区间：-0.027，-0.005），其他 BMI 类别则无此现象。
在我们的早期 LCPD 儿童队列中，随时间推移负重限制并未导致 BMI Z 评分出现有临床意义的增加。体重增加是多因素的，可能不仅仅是由负重限制引起的。
III 级诊断研究。
