In vivo 3D analysis of clavicular kinematics during scapular plane abduction: comparison of dominant and non-dominant shoulders.

The purpose of this study was to evaluate side-to-side differences in three-dimensional clavicle kinematics in normal shoulders during dynamic scapular plane elevation using model-image registration techniques. Twelve healthy males with a mean age of 32 years (range, 27-36 years old) were enrolled in this study. Clavicle rotations were computed with bilateral fluoroscopic images and CT-derived bone models using model-image registration techniques and compared between dominant and nondominant shoulders. There was no difference in retraction between both shoulders. The clavicle in dominant shoulders was less elevated during abduction than in nondominant shoulders (P=0.03). Backward rotation angles of dominant shoulders were significantly smaller than those of nondominant shoulders throughout the activity (P=0.03). Clavicular kinematics during scapular plane abduction were different according to hand-dominance.