Background: 

The Green-Anderson (GA) leg-length data remain the gold standard for the age-based assessment of leg lengths in children despite their methodologic weaknesses. We aimed to summarize current growth trends among a cross-sectional cohort of modern U.S. children using quantile regression methods and to compare the median femoral and tibial lengths of the modern U.S. children with those of the GA cohort.

Methods: 

A retrospective review of scanograms and upright slot-scanning radiographs obtained in otherwise healthy children between 2008 and 2020 was completed. A search of a radiology registry revealed 3,508 unique patients between the ages of 2 and 18 years for whom a standard-of-care scanogram or slot-scanning radiograph had been made. All patients with systemic illness, genetic conditions, or generalized diseases that may affect height were excluded. Measurements from a single leg at a single time point per subject were included, and the latest available time point was used for children who had multiple scanograms made. Quantile regression analysis was used to fit the lengths of the tibia and femur and overall leg length separately for male patients and female patients.

Results: 

Seven hundred patients (328 female and 372 male) met the inclusion criteria. On average, the reported 50th percentile tibial lengths from the GA study at each time point were shorter than the lengths in this study by 2.2 cm (range, 1.4 to 3.3 cm) for boys and 2 cm (range, 1.1 to 3.1 cm) for girls. The reported 50th percentile femoral lengths from the GA study at each time point were shorter than the lengths in this study by 1.8 cm (range, 1.1 to 2.5 cm) for boys and 1.7 cm (range, 0.8 to 2.3 cm) shorter for girls.

Conclusions: 

This study developed new growth charts for femoral and tibial lengths in a modern U.S. population of children. The new femoral and tibial lengths at nearly all time points are 1 to 3 cm longer than traditional GA data. The use of GA data for epiphysiodesis could result in underestimation of expected childhood growth.

Level of Evidence: 

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

中文翻译：

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21 世纪美国儿童现代人群的标准股骨和胫骨长度

背景： 

Green-Anderson (GA) 腿长数据仍然是基于年龄的儿童腿长评估的黄金标准，尽管其方法论存在缺陷。我们的目的是使用分位数回归方法总结现代美国儿童横断面队列的当前生长趋势，并将现代美国儿童的股骨和胫骨长度中位数与 GA 队列进行比较。

方法： 

完成了对 2008 年至 2020 年间在其他方面健康的儿童中获得的扫描图和直立槽扫描射线照片的回顾性审查。对放射学登记处的搜索显示了 3,508 名年龄在 2 至 18 岁之间的独特患者，他们已经为他们制作了标准护理扫描图或狭缝扫描射线照片。所有患有全身性疾病、遗传病或可能影响身高的全身性疾病的患者均被排除在外。包括每个受试者在单个时间点从单条腿进行的测量，并且最新的可用时间点用于制作了多个扫描图的儿童。采用分位数回归分析分别拟合男性患者和女性患者的胫骨和股骨长度以及腿部全长。

结果： 

700 名患者（328 名女性和 372 名男性）符合纳入标准。平均而言，在每个时间点，GA 研究报告的第 50 个百分位胫骨长度比本研究的长度短 2.2 厘米（范围，1.4 至 3.3 厘米）的男孩和 2 厘米（范围，1.1 至 3.1 厘米）的男孩女孩们。GA 研究报告的每个时间点的第 50 个百分位股骨长度比本研究中男孩的长度短 1.8 厘米（范围，1.1 至 2.5 厘米），女孩短 1.7 厘米（范围，0.8 至 2.3 厘米）。

结论： 

这项研究为现代美国儿童人群的股骨和胫骨长度开发了新的生长图表。几乎所有时间点的新股骨和胫骨长度都比传统 GA 数据长 1 至 3 厘米。使用 GA 数据进行骨骺分离可能会导致低估预期的儿童生长。

证据等级： 

预后等级 IV。有关证据等级的完整描述，请参阅作者须知。