Abstract :
[en] Background: The contralateral shoulder is often used as a reference when evaluating a pathological shoulder. However literature provides contradictory results regarding the symmetry of the scapular pattern in a healthy population. We assume that several factors including the gender and the type of motion may influence the scapula bilateral symmetry.
Method: The dominant and non dominant shoulders of two populations of men and women composed of 11 subjects each were evaluated for three distinct motions: flexion in the sagittal plane, abduction in the frontal plane and gleno-humeral internal/external rotation with the arm abducted at 90°. Posture, kinematic and range of motion were studied separately.
Results: Asymmetries are observed for motions performed in the frontal and sagittal plane but not for the internal/external rotation with the arm abducted at 90°. Multiplane asymmetries are observed for the male population, whereas asymmetries for the female one are mainly uniplanar. For both men and women, the scapula has a larger upward rotation on the dominant side. For men, a larger posterior tilt is also observed. The asymmetries mainly originate in the scapula kinematic and not in its original posture.
Discussion: Even if the asymmetries are not large in terms of amplitude (inferior to 5°), one should be aware of their existence and the influence of the composition of the studied population when using the contralateral shoulder as a reference.
Scopus citations®
without self-citations
21