Comparison of Glenohumeral Range of Motion in Throwing Athletes versus Non-Throwing Athletes

Abstract

It has been hypothesized in the sports medicine community that all athletes have a comparable amount of glenohumeral range of motion (ROM). However, very little research has been conducted comparing glenohumeral ROM in throwing athletes versus non-thro wing athletes. PURPOSE: To investigate the difference in glenohumeral ROM between throwing athletes and non-throwing athletes. METHODS: Fourteen current Division I athletes (age=21.72 + 2.80 years) served as participants. The participants included throwing athletes (n=7; male=4, female=3) and non-throwing athletes (n=7; male=4, female=3). All participants had his or her passive glenohumeral ROM (internal rotation, external rotation, horizontal adduction, and horizontal abduction) measured with a manual goniometer. Total rotational ROM was then calculated by adding the amount of external rotation to the amount of internal rotation, and total horizontal ROM was calculated by adding the total amount of horizontal adduction to the total amount of horizontal abduction. All data was analyzed with a 2 (athlete) × 2 (ROM) ANOVA, with repeated measures on the last factor. RESULTS: It was hypothesized that there would be no difference between rotational or horizontal range of motion at the glenohumeral joint of the throwing and non-throwing athletes. Results revealed no significant difference between throwers and non-throwers (p<.05) in either plane of motion. CONCLUSION: No significant difference indicates that throwers and non-throwers have comparable ROM at the shoulder. The trends in this data however, indicate that the throwers actually have less ROM at the shoulder than do the non-throwers. This trend was unexpected and leads to some interesting future research questions. For example, does this “tightness” pre-dispose the throwers to shoulder injuries or is it a protective mechanism used to maintain joint integrity during large angular accelerations.