Asymmetric Resting Shoulder Position In Healthy Overhead Athletes

• Published in: Journal of athletic training Vol. 42; no. 2; pp. S - 124
• Main Authors: Oyama, S, Myers, J B, Wassinger, CA, Ricci, R D, Abt, J P, Conley, K M, Lephart, S M
• Format: Journal Article
• Language: English
• Published: 01.06.2007
• ISSN: 1062-6050

Context: Scapular malposition, Inferior medial border prominence, C oracoid pain and malposition, and dysK inesis of scapular movement (SICK) are associated with shoulder injury in overhead athletes. Those with SICK scapula are believed to have asymmetric resting scapular position as a result of increased scapular protraction, anterior tipping and internal rotation of the dominant shoulder, yet the asymmetry of the resting scapular position and the contributors to the asymmetry have not been investigated. Additionally, symmetry of the resting scapular position in healthy overhead athletes needs to be evaluated for comparison with injured individuals. If similar degrees of asymmetry in the resting scapular position is present in healthy overhead athletes, asymmetry alone may not suggest the presence of SICK scapula in injured overhead athletes. The objective of this study was to assess symmetry of the resting scapular position and contributing scapular kinematics in healthy overhead athletes. Conclusions: Asymmetry in the resting scapular position and orientation was found in healthy overhead athletes. The pattern of bilateral difference in scapular position and orientation found in this study supports the theory that asymmetry in the resting scapular position is the result of decreased scapular retraction (increased protraction), increased anterior tipping, and internal rotation of the dominant shoulder. The presence of resting scapular position asymmetry in healthy overhead shoulders suggests that this may be a normal adaptation in overhead athletes. Although the asymmetry was present in the healthy overhead athletes, the differences between dominant and non-dominant shoulders found in this study were relatively small (bilateral difference: 1.9 degree - 3.9 degree ). It remains unknown how resting shoulder position asymmetry in injured overhead athletes compares to healthy overhead athletes. Further investigation of bilateral resting scapular position in injured overhead athletes and non-overhead athletes is needed to further understand the implication of this resting scapular position asymmetry on shoulder pathologies.