Lines of action and stabilizing potential of the shoulder musculature
David C Ackland, Marcus G Pandy
JOURNAL OF ANATOMY | WILEY | Published : 2009
The objective of the present study was to measure the lines of action of 18 major muscles and muscle sub-regions crossing the glenohumeral joint of the human shoulder, and to compute the potential contribution of these muscles to joint shear and compression during scapular-plane abduction and sagittal-plane flexion. The stabilizing potential of a muscle was found by assessing its contribution to superior/inferior and anterior/posterior joint shear in the scapular and transverse planes, respectively. A muscle with stabilizing potential was oriented to apply more compression than shear at the glenohumeral joint, whereas a muscle with destabilizing potential was oriented to apply more shear. Si..View full abstract
This work was supported by a fellowship from the Victorian Endowment for Science, Knowledge, and Innovation (VESKI) to M.G.P. and a Melbourne School of Engineering Scholarship to D.C.A. We thank Dr Anthony Schache for reviewing an earlier draft of this manuscript.