Three-dimensional rotation of the scapula during functional movements: An in vivo study in healthy volunteers

Douglas A. Bourne, Anthony M.T. Choo, William D. Regan, Donna L. MacIntyre and Thomas R. Oxland

The goal of this study was to measure 3-dimensional shoulder motion by use of a direct invasive technique during 4 different arm movements in healthy volunteers. Eight subjects with healthy shoulders were recruited. Optoelectronic marker carriers were mounted on bone pins, which were inserted into the lateral scapular spine. Subjects performed 4 different arm movements while the motion was being recorded by a precision optoelectronic camera. During abduction, the scapula tipped posteriorly (44° ± 11°), rotated upward (49° ± 7°), and rotated externally (27° ± 11°). For reaching, the scapula consistently rotated upward (17° ± 3°) and rotated internally (18° ± 6°) whereas tipping was generally less than 10° (5° ± 2°). Overall, the range of scapular movement for the hand behind the back was small and variable, with most rotations not exceeding 15°. For horizontal adduction, the scapula tipped anteriorly (8° ± 3°), rotated upward (5° ± 2°), and rotated internally (27° ± 6°). The authors conclude that these scapular rotations provide normative data that will be useful for diagnosing scapular dysfunction.

Journal of Shoulder and Elbow Surgery, Volume 16, Issue 2, March-April 2007, Pages 150-162

View Abstract

Full text with Athens login

Common Biomechanical Errors in Runners

Join Ari Kaplan and Doug Adams in this short online course to explore how to identify common running styles and the biomechanical issues related to each category.