Rotator cuff tear incidence may be associated with osteophytes, not critical shoulder angle
In an evaluation of related factors for rotator cuff tears, results showed rotator cuff tears were more affected by heel-type osteophytes than critical shoulder angle.
Researchers categorized patients with (n=214) and without (n=109) full-thickness rotator cuff tears who underwent MRI and radiographic imaging of the shoulder into a high critical shoulder angle group of greater than 38°, a middle critical shoulder angle group of 33° to 38° and a low critical shoulder angle group of less than 33°. The presence of heel-type osteophytes and quadrangular osteophytes protruding inferiorly from the undersurface of the anterolateral acromion, like the heel of the shoe, were confirmed, while researchers excluded other types of osteophytes.
Results showed rotator cuff tears were present in 84.6% of the high critical shoulder angle group, 60.3% of the middle critical shoulder angle group and 68.3% of the low critical shoulder angle group. Researchers found 76.9%, 38.5% and 52.6% of patients without an osteophyte in the high, middle and low critical shoulder angle groups, respectively, had a rotator cuff tear. Rotator cuff tears were found in 92.3%, 80.3% and 92.2% of patients with an osteophyte in the high, middle and low critical shoulder angle groups, respectively, according to results. Univariate regression analysis showed rotator cuff tear was associated with critical shoulder angle group and the presence of osteophyte, but not with age or sex. Although presence of an osteophyte showed a significant relation with rotator cuff tear in multivariate logistic regression analysis, researchers found no significant relation between critical shoulder angle and rotator cuff tear.
“The present findings inform the clinically important suggestion that although [critical shoulder angle] CSA might be correlated with [rotator cuff tear] RCT, a CSA study without considering presence of an osteophyte should be interpreted with caution,” the authors wrote. – by Casey Tingle
Disclosures: The authors report no relevant financial disclosures.