Affiliations: [a] Dept of Physical Medicine and Rehabilitation, Mayo
Clinic Sports Medicine Center, Mayo Clinic, Rochester, MN 55905, USA | [b] Mayo Clinic Motion Analysis Laboratory, Rochester, MN
55905, USA
Note: [] Dept. of Physical Medicine and Rehabilitation, Mayo Clinic, 200
First Street, SW, Rochester, MN 55905, USA. Tel.: +1 507 284 1643; Fax: +1 507
284 3431; E-mail: smith.jay@mayo.edu
Abstract: Scapular position has been hypothesized to influence rotator cuff
function, but no current methods exist to reliably measure shoulder rotation
strength in different scapular positions. The purpose of this study was to
develop a reliable technique to measure isokinetic (ISOK) and isometric (ISOM)
shoulder rotation strength with the scapula protracted. Ten healthy volunteers
(5 male, 5 female, ages 20--41) completed two to three ISOM and five ISOK (90
degrees/second) internal rotation (IR) and external rotation (ER) repetitions
in a position of scapular protraction with the shoulder abducted 45 degrees in
the scapular plane. Subjects returned 24--72 hours later to repeat testing. All
torque measurements in the protracted position exhibited excellent intersession
reliability (ICCs > 0.97). Shoulder rotational torque can be
measured in the protracted scapula position with excellent reliability using
the new technique described. Establishing the reliability of the protracted
technique is a necessary prerequisite for the completion of future studies
examining quantitative differences in rotational torque generation between the
neutral and protracted scapula positions in the functional shoulder position of
45 degrees of scapular plane abduction.
