Affiliations: Liberty Mutual Research Institute for Safety, Hopkinton, MA 01748, USA
Correspondence:
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Address for correspondence: Krystyna Gielo-Perczak, Liberty Mutual Research Institute for Safety, 71 Frankland Road, Hopkinton, MA 01748, USA. Tel.: +1 508 497 0218; Fax: +1 508 435 0482; E-mail: Krystyna.Gielo-Perczak@libertymutual.com
Abstract: The current study proposes a method of geometrical description of the shoulder articulating surfaces in order to deduce an unrecognized relationship between shoulder geometry and strength during a one-handed pulling task. The paper reports the results of a study of the strength of 12 participants during one-handed pulling correlated with the geometries of their shoulder joints derived from magnetic resonance imaging (MRI) scans. The measurements of a mean force during pulling were recorded when an upper arm was adducted in the frontal plane from 5 to 30 degrees during maximum voluntary contraction (MVC). It was observed in the study that an area determined by the height and width of the glenoid fossa closely relates to the mean force during pulling.
Keywords: one-handed pulling in frontal plane, shoulder joint, maximum acceptable load, geometry of joint articulating surfaces