The amount of glenohumeral joint internal and external rotation used during overhead sport activities has been measured experimentally by sports scientists. Clinical measurement of glenohumeral joint internal and external rotation using goniometry is an integral part of a shoulder evaluation after injury or surgery or during preseason or preventative musculoskeletal screenings.
Purpose: This study measured glenohumeral joint internal and external rotation in two groups of unilaterally dominant upper extremity athletes to compare the total arc of rotational range of motion between the dominant and nondominant extremities.
Methods: A total of 163 elite athletes (117 male junior tennis players and 46 male baseball pitchers) were measured for glenohumeral joint internal and external rotation at 90 degrees of abduction. Total rotation range of motion was calculated by summing internal and external rotation measures in each extremity.
Results: An ANOVA with post hoc testing revealed no significant difference (P > 0.05) between extremities in baseball pitchers for total rotation range of motion (145.7 vs 146.9), whereas significantly less (P < 0.001) dominant arm total rotation range of motion was identified in the elite junior tennis players (149.1 vs 158.2).
Conclusion: This study has identified unique glenohumeral joint rotational patterning in unilaterally dominant upper extremity athletes that has ramifications for rehabilitation after injury and for both injury prevention and performance enhancement.