Residual Effects of Glenohumeral Range of Motion, Strength, and Humeral Retroversion on Prior Overhead Athletes After Cessation of Sport

Abstract

Background: Research has shown that repetitive stress from playing an overhead (OH) sport can cause musculoskeletal and osseous adaptations to occur on the dominant side. Additionally, there are limited data about the residual effects of these adaptations after the cessation of sports participation. Purpose: To investigate the effects of prior participation in an OH sport versus not participating in an OH sport on glenohumeral range of motion (ROM), isometric strength, and humeral retroversion (HR). Study Design: Cross-sectional study; Level of evidence, 3. Methods: Forty-eight college-aged individuals participated. Participants were split into 2 groups: (1) individuals who previously participated in an OH sport (n = 20; age, 20.3 ± 1.1 years; height, 166.3 ± 15.27 cm; weight, 72.2 ± 13.5 kg) and (2) individuals who previously did not play an OH sport (n = 28; age, 20.6 ± 0.9 years; height, 168.8 ± 6.3 cm; weight, 68.1 ± 15.1 kg). After completing a health history questionnaire, the following were measured: side-to-side shoulder internal rotation (IR) and external rotation (ER) ROM via an inclinometer, isometric shoulder strength via a handheld dynamometer, and HR using an ultrasound imaging machine. A Mann-Whitney U test was used to determine group differences, and a Wilcoxon t test was used to analyze side-to-side differences within each group. Results: The Mann-Whitney U test revealed a statistically significant group difference for dominant shoulder ER ROM ( U = 162.00, P = .014). Specifically, the prior OH group had significantly more ER than the control group. Within the prior OH group, testing revealed that athletes had significantly more HR ( Z =–2.782, P = .005), ER ROM ( Z =–1.979, P = .048), and ER isometric strength ( Z =–2.763, P = .006) on their dominant than nondominant shoulder and significantly less IR ROM ( Z =–3.099, P = .002) on their dominant than nondominant shoulder. Conclusion: Prior OH sports participation may have residual osseous and musculoskeletal effects that remain after cessation of the sport.