Subacromial impingement and posture

Background:

It has been suggested that dysfunctional posture of the scapula, thoracic spine, and cervical spine is associated with the development of subacromial impingement syndrome (SIS).

Objectives:

This paper explores the current literature describing the association between static posture and SIS.

Major findings:

Thirty-one articles were included in this review. Nine of these articles looked specifically at the resting posture in subjects with SIS. All nine of these studies found no correlation between static posture and SIS. Fifteen articles included subjects without SIS and/or non-self-selected resting posture. Of those, nine provided support for the plausibility of a relationship between SIS and posture. Seven of the studies included in this review examined treatment aimed at posture. Only one looked specifically at the effects of postural correction in subjects with SIS and found that it improved pain-free shoulder range of motion (ROM) but there was no change in pain intensity. Three out of four studies, which examined the ability of stretching and strengthening exercise to change posture, found that exercise can have an effect on posture. Several limitations were present in the articles that reduce the strength of the conclusions. These include the heterogeneity of the SIS diagnosis, limited information on subject variables, complexity of measuring posture, lack of blinding, and limited reporting of power analysis.

Conclusion:

This review has highlighted the current lack of strong evidence to support an association between posture and SIS. The evidence examining this association is plagued by poorly defined diagnostic criteria, wide sample variation, and poor statistical power. Clinicians should be mindful of the current evidence pointed out in this review when considering using posture as a diagnostic and interventional strategy for patients with SIS.