Shoulder pain is a common musculoskeletal complain. A common view related to rotator cuff pathology is that decreased scapulothoracic upward rotation increases the risk of subacromial rotator cuff compression by reducing the space for rotator cuff clearance. However, the changes in subacromial distance during abduction in subjects with reduced scapulothoracic upward rotation remain unclear.
In forty participants, the minimum distance between the coracoacromial arch and rotator cuff insertions, the rotator cuff insertion surface area in proximity with the coracoacromial arch, and the prevalence of contact between the coracoacromial arch and rotator cuff were determined using fluoroscopy and shape-matching.
Decreased scapulothoracic upward rotation shifts the range of motion in which subacromial distances are smallest to lower angles.
This finding should assist in exercise prescription to avoid prolonged and repeated exposures within the range of closest proximity.
The lack of difference in the number of symptomatic patients in the low and high scapulothoracic upward rotation puts into question the relevance of this clinical finding.
> From: Lawrence et al., J Orthop Sports Phys Ther 49 (2019) 180-191 (Epub ahead of print). All rights reserved to Journal of Orthopaedic & Sports Physical Therapy. Click here for the online summary.
Expert opinion by José Pedro Correia
This is an interesting study, as it shows that not only: 1) there is a low prevalence of subacromial contact with the rotator cuff during abduction; but also 2) that the range of upward scapular rotation does not seem to influence this contact or its relation to pain complaints, instead just shifting it to lower ranges in decreased rotation.
If patients show complaints consistent with the regions of closer proximity according to their degree of scapular rotation, then it might be useful to adapt exercise prescription to more comfortable ranges.
