BACKGROUND: The multifidus muscle plays a major role in the growth and postural control of children. Therefore, the reference values of the cross-sectional area (CSA) of the lumbar multifidus muscle represent an important tool for assessing muscle development and the early monitoring of musculoskeletal disorders. OBJECTIVE: The aim of this study was to provide percentile scores for the CSA of the lumbar multifidus muscle in eutrophic children aged 5 to 10 years. METHODS: This was a cross-sectional, observational study, involving 736 children. An anthropometric assessment was conducted and ultrasound (US) imaging was used to assess the CSA of the lumbar (vertebral level L5) multifidus muscle. The CSA was expressed as percentile scores. RESULTS: The CSA in the boys ranged from 1.8 cm2 to 5.3 cm2 and in girls from 1.9 cm2 to 5.9 cm. The CSA in the 50th percentile scores of both sexes was 3.4 cm2. There was an increase in the CSA between 5 and 7 years old in both sexes. The CSA presented a greater variance in girls than in boys. After 8 years of age, the multifidus CSA increased in girls and decreased in boys. CONCLUSION: The present study has provided percentile scores for the CSA of the lumbar multifidus muscle for eutrophic children aged 5 to 10 years. An increase was observed of the CSA of the multifidus muscle between the ages of 5 and 7 years and there were no differences in the CSA percentiles in relation to sex. An increase in the CSA after 8 years of age was only observed in the girls.

中文翻译：

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儿童腰多裂肌横截面积参考值

背景：多裂肌在儿童的生长发育和姿势控制中起着重要作用。因此，腰多裂肌横截面积 (CSA) 的参考值是评估肌肉发育和早期监测肌肉骨骼疾病的重要工具。目的：本研究的目的是为 5 至 10 岁的富营养化儿童腰部多裂肌的 CSA 提供百分位评分。方法：这是一项横断面观察性研究，涉及 736 名儿童。进行了人体测量评估，并使用超声 (US) 成像评估腰椎（椎骨水平 L5）多裂肌的 CSA。CSA 表示为百分位数分数。结果：男孩的 CSA 范围为 1.8 cm2 至 5.3 cm2，女孩的范围为 1.9 cm2 至 5.9 cm。两种性别的第 50 个百分位分数的 CSA 均为 3.4 cm2。在 5 到 7 岁之间，两种性别的 CSA 都有所增加。CSA 在女孩中的差异大于男孩。8岁以后，女孩的多裂肌CSA增加，男孩减少。结论：本研究提供了 5 至 10 岁营养不良儿童腰部多裂肌 CSA 的百分位评分。观察到 5 至 7 岁之间多裂肌的 CSA 有所增加，并且 CSA 百分位数与性别没有差异。仅在女孩中观察到 8 岁后 CSA 增加。8岁以后，女孩的多裂肌CSA增加，男孩减少。结论：本研究提供了 5 至 10 岁营养不良儿童腰部多裂肌 CSA 的百分位评分。观察到 5 至 7 岁之间多裂肌的 CSA 有所增加，并且 CSA 百分位数与性别没有差异。仅在女孩中观察到 8 岁后 CSA 增加。8岁以后，女孩的多裂肌CSA增加，男孩减少。结论：本研究提供了 5 至 10 岁营养不良儿童腰部多裂肌 CSA 的百分位评分。观察到 5 至 7 岁之间多裂肌的 CSA 有所增加，并且 CSA 百分位数与性别没有差异。仅在女孩中观察到 8 岁后 CSA 增加。观察到 5 至 7 岁之间多裂肌的 CSA 有所增加，并且 CSA 百分位数与性别没有差异。仅在女孩中观察到 8 岁后 CSA 增加。观察到 5 至 7 岁之间多裂肌的 CSA 有所增加，并且 CSA 百分位数与性别没有差异。仅在女孩中观察到 8 岁后 CSA 增加。