Article

The aim of this study was to investigate differences in muscle
stiffness between subjects with stiff shoulders and controls, and to determine
the correlation between posterior shoulder muscle stiffness and range of motion of rotation. DESIGN: Prospective, cross-sectional study.
SUBJECTS: Twenty
subjects with stiff shoulder and 20 healthy subjects.
METHODS: Range of motion of
rotation, and stiffness in 4 muscles (posterior deltoid, infraspinatus, teres
minor and teres major), were measured in affected shoulders and control shoulders
using a goniometer and a Myotonometer, respectively. RESULTS: Patients with stiff
shoulder had greater muscle stiffness than controls.
Except for the teres major,
significant correlations were found between internal rotation and stiffness of 3
muscles (r = 0.57-0.72). Among these 3 muscles, posterior deltoid muscle
stiffness accounted for 51% of the variance in shoulder internal rotation beyond
stiffness from the infraspinatus and teres minor muscles. CONCLUSION: These
findings support that muscle stiffness is related to shoulder range of motion. It
is important to consider the posterior deltoid, infraspinatus, and teres minor
muscles in the rehabilitation of patients with restricted internal rotation of the shoulder.

Langue : ANGLAIS