A proposal for a new definition of the axial rotation angle of the shoulder joint

The Euler/Cardan angles are commonly used to define the motions of the upper arm with respect to the trunk. This definition, however, has a problem in that the angles of both the horizontal flexion/extension and the axial rotation of the shoulder joint become unstable at the gimbal-lock positions. In this paper, a new definition of the axial rotation angle was proposed. The proposed angle was stable over the entire range of the shoulder motion. With the new definition, the neutral position of the axial rotation agreed with that in the conventional anatomy. The advantage of the new definition was demonstrated by measuring actual complex motions of the shoulder with a three-dimensional motion capture system.

Author Affiliation:

(a) School of Biomedical Science, Tokyo Medical and Dental University, Tokyo 113-8510, Japan

(b) Institute of Biomaterials and Biomedical Engineering, Tokyo Medical and Dental University, Tokyo 101-0062, Japan

(c) Department of Rehabilitation Medicine, Tokyo Medical and Dental University, Tokyo 113-8519, Japan

Article History:

Received 9 March 2006; Revised 6 July 2006; Accepted 10 August 2006

Source Citation:Masuda, Tadashi, Akimasa Ishida, Lili Cao, and Sadao Morita. "A proposal for a new definition of the axial rotation angle of the shoulder joint.(Author abstract)(Report)." Journal of Electromyography and Kinesiology 18.1 (Feb 2008): 154(6). Academic OneFile. Gale. BROWARD COUNTY LIBRARY. 3 Aug. 2009
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