Article

PURPOSE: To systematically review the evidence in support of the purported
function of the rotator cuff muscles as dynamic stabilizers of the glenohumeral
joint. METHODS: Electronic searches were conducted using AMED, CINAHL, Medline
and SPORT Discus. Studies were required to include at least one characteristic of
a stabilizer muscle. Quality analysis was completed by two assessors
independently. Data were extracted for four main characteristics of stabilizer
muscles: (1) moment arm length, (2) onset of muscle activity, (3) joint stiffness
as measured by contribution of muscle activity to prevent joint translation, (4)
co-contraction as demonstrated by electromyography muscle activity and
co-activation ratio. RESULTS: Twenty of the 1726 identified studies were selected
for the review. Rotator cuff muscles can limit joint translation (five studies)
and contribute to joint stiffness (one study), possess shorter moment arms in
some movements (three studies), but show limited evidence for stabilizing
characteristics of early onset (seven studies) and co-contraction (seven
studies). CONCLUSION: The rotator cuff muscles exhibited some stabilization
characteristics but not all. On the basis of our current low to moderate quality
evidence, the most likely, but as yet unverified, stabilization role for the
rotator cuff muscles appears to be limiting of translation in a
direction-specific manner. IMPLICATIONS FOR REHABILITATION: Diagnostic tests
currently used are based largely on the assumption that the muscles of the
rotator cuff can be individually recruited as prime movers. Our findings
demonstrate the need for more research into the proposed stabilizing mechanisms
of the rotator cuff muscles to increase diagnostic accuracy and more targeted
shoulder rehabilitation programs. It may be that the rotator cuff muscles have a
role in limiting glenohumeral joint translation which is not reflected in the
current diagnostic tests and rehabilitation protocols. Further research is
required to establish this stabilizing characteristic in living subjects.
Knowledge of the contribution of rotator cuff muscle activation in limiting joint
translation may be an important aspect in properly assessing and quantifying the
proposed function of the rotator cuff muscles as dynamic stabilizers of the
shoulder joint.

Langue : ANGLAIS