COMPARISON OF GLENOHUMERAL JOINT ROTATION RANGE OF MOTION IN YOUNG ATHLETES

ABSTRACT Introduction: Overhead-throwing athletes undergo changes in shoulder range of motion (ROM) due to sports activities, such as excessive amplitude, lateral rotation (LR) increase and medial rotation (MR) restriction. Asymmetry greater than 20° may render athletes more prone to injuries. There are similarities among sports featuring overhead throwing due to the considerable amount of movements involving maximum lateral rotation. In these sports, medial rotation (MR) restriction, excess of lateral rotation (LR) and shoulder pain are common, particularly in overhead-throwing athletes. Objective: To assess shoulder MR and LR ROM in athletes participating in different sports, considering the influence of these variables on injuries and functional performance. Methods: The rotation ROM of the glenohumeral joint was assessed in 477 young athletes, who were categorized in three sports groups: swimming, overhead-throwing and non-overhead throwing, distributed by age group. Analyses of Variance (ANOVA) were performed to verify if there were differences in MR and LR between groups and paired Student t test was used to verify differences between sides (asymmetry). Results: Youngest athletes showed significant shorter LR than the oldest, in both sides. This study demonstrated that the right side has less MR and greater LR in all groups. Conclusion: The findings showed that overhead-throwing and swimming groups have similarities in shoulder rotation ROM. Level of evidence III; Diagnostic Studies - Investigating a Diagnostic Test.

摘要
引言：过顶投掷运动员因专项运动导致肩关节活动度（range of motion, ROM）发生改变，具体表现为活动幅度过大、外旋（lateral rotation, LR）增加以及内旋（medial rotation, MR）受限。双侧肩活动度不对称度超过20°时，运动员的损伤风险将显著升高。由于诸多动作均需达到最大外旋幅度，各类过顶投掷类运动存在共性特征。此类运动中，内旋受限、外旋过度与肩痛均为常见问题，在过顶投掷运动员群体中尤为突出。
研究目的：评估参与不同运动项目运动员的肩关节内旋与外旋活动度，并分析这两项指标对运动员损伤风险与运动功能表现的影响。
研究方法：共纳入477名青年运动员，对其盂肱关节旋转活动度进行评估；所有受试者按运动项目分为游泳组、过顶投掷组与非过顶投掷组，并按年龄分组进行分层。采用方差分析（Analysis of Variance, ANOVA）比较三组运动员的肩关节内旋与外旋活动度差异，采用配对样本Student t检验分析双侧肩活动度的差异（即不对称度）。
研究结果：双侧肩外旋活动度均显示，最年轻组运动员的外旋幅度显著低于最年长组。本研究同时发现，所有组别运动员的右侧肩内旋幅度均小于左侧，而右侧肩外旋幅度则大于左侧。
研究结论：本研究结果表明，过顶投掷组与游泳组运动员的肩关节旋转活动度存在相似特征。证据级别Ⅲ；诊断性研究——诊断试验研究。