Findings published online in the journal Clinical Orthopaedics and Related Research cast doubt on the relationship of critical shoulder angle (CSA) to rotator cuff disease. 

The researchers retrospectively compared data on 313 patients with asymptomatic rotator cuff tear who underwent ultrasonography and standardized anteroposterior radiographs at enrollment and yearly thereafter during a median of 4 years. Of 1,552 radiographs evaluated, they found that 326 (21 percent) were of sufficient quality to measure CSA. The researchers noted that CSA was higher among patients with cuff tears than control patients, but CSA did not correlate with baseline tear length or width, and CSA was not different between tears that enlarged and those that were stable. In addition, CSA did not change over time. Learn more...