Objective: This study investigated the hypothesis that tennis players with scapular dyskinesia present a smaller subacromial space than non-athletes. Additionally, the correlation between the size of the subacromial space and abnormalities in scapular movement during arm abduction was investigated.
Design: Cross sectional study.
Participants: A total of 53 elite tennis players and 20 control subjects were enrolled in the study. Participation was restricted to elite-level, junior tennis players who had no current shoulder pain or history of shoulder injuries.
Intervention: Each individual was examined for scapular dyskinesia by a single physician and by ultrasound, with the results analyzed in a blind fashion by a single radiologist.
Results: 43.4% of the tennis players and 20% of control subjects presented scapular dyskinesia. Of the 106 shoulders evaluated, 39.6% of tennis players and 10% of control subjects presented scapular dyskinesia in the clinical examination (p=0.005). Ultrasonographic measurements demonstrated that tennis players presented statistically smaller subacromial spaces compared to control subjects (p<0.001). A decrease in the subacromial space was observed in tennis players when the shoulder was raised from zero to 60° of abduction. However, dyskinesia-afflicted athletes demonstrated a significantly greater decrease following this movement (19,3 mm versus 13.8mm, p=0.002).
Conclusion: This study demonstrated that tennis players with scapular dyskinesia present a smaller subacromial space than control subjects. Additionally, when the shoulder was analyzed dynamically, moving from neutral abduction to 60° of elevation, the tennis players with scapular dyskinesia presented a greater reduction in the subacromial space compared to unaffected athletes.