Purpose
To summarize the available evidence and examine the relationship between the critical
shoulder angle (CSA) and (1) the incidence of chronic full-thickness rotator cuff
tears (RCTs) and (2) outcomes after rotator cuff repair (RCR).
Methods
A comprehensive search of MEDLINE, Embase, and CINAHL was completed. Comparative studies
were included and the influence of the CSA on either the incidence of chronic, full-thickness
RCTs, or outcomes following RCR was evaluated. Demographic variables and outcomes
were collected.
Results
Seven comparative studies analyzed the influence of the CSA on the incidence of chronic,
full-thickness RCTs (the control group constituted patients with a normal rotator
cuff). High heterogeneity limited pooling of studies, but the majority concluded that
a greater CSA significantly increased the likelihood of a chronic, full-thickness
RCT. Conversely, 5 comparative studies analyzed the influence of CSA on outcomes following
RCR, and although a greater CSA was associated with a greater re-tear rate, the majority
reported that CSA did not significantly influence postoperative functional outcomes,
including patient-reported outcome measures (PROMs), range of motion (ROM), and strength.
Conclusions
Based on the available evidence, there appears to be a relationship between a greater
CSA and the presence of a chronic, full-thickness RCT. Furthermore, a greater CSA
may be associated with a greater re-tear rate following RCR; however, CSA does not
appear to influence functional outcomes following RCR. Despite these observations,
the available evidence is of poor quality, and the clinical utility and role of the
CSA in the diagnosis and surgical management of a chronic, full-thickness RCT remains
in question.
Level of Evidence
Level IV: Systematic review of Level II-IV studies.
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Article info
Publication history
Accepted:
May 23,
2019
Received:
December 6,
2018
Footnotes
The authors report the following potential conflicts of interest or sources of funding: C.V. reports grants and personal fees from Zimmer Biomet, grants and personal fees from Smith & Nephew, grants and personal fees from Medtronic, and grants from Toronto General and Western Hospital Foundation, outside the submitted work. Full ICMJE author disclosure forms are available for this article online, as supplementary material.
See commentary on page 3144
Identification
Copyright
© 2019 Published by Elsevier on behalf of the Arthroscopy Association of North America
ScienceDirect
Access this article on ScienceDirectLinked Article
- Editorial Commentary: #Fakeradiographicangle—Critical Shoulder Angle, Like Acromioplasty, May Not Be CriticalArthroscopyVol. 35Issue 11
- PreviewThe critical shoulder angle (CSA) is found to have an association with rotator cuff tearing when the angle is greater than 35° to 38°. However, the CSA does not correlate with improved clinical patient outcome scores. Acromioplasty is no longer viewed as a critical part of rotator cuff surgery. Only meaningful comparative studies will allow us to conclude whether performing a lateral acromioplasty for a significant CSA will be an important step to prevent future retears after rotator cuff repair.
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