The significance of subjective mechanical symptoms in rotator cuff pathology

The presence of subjective mechanical symptoms, such as clicking or popping, is common in patients presenting for shoulder pain and dysfunction, with unclear clinical significance. The primary objective of this study was to assess whether subjective mechanical symptoms in the affected shoulder were associated with full-thickness rotator cuff tearing in a consecutive, prospective cohort of patients undergoing shoulder magnetic resonance imaging (MRI) for suspected rotator cuff pathology.

A prospective cohort study was performed of 100 consecutive patients with suspected rotator cuff tendinopathy and/or tearing who underwent shoulder MRI. The presence of subjective shoulder mechanical symptoms, including clicking or popping, was documented prior to MRI. Indications for MRI included weakness on isolated testing of rotator cuff muscle(s) or symptoms refractory to conservative treatment including at least a 6-week course of physical therapy. The primary outcome variable was the presence of full-thickness rotator cuff tearing; secondary outcome variables included any (full-thickness or partial-thickness) rotator cuff tearing and biceps long head subluxation. Radiographic parameters, including critical shoulder angle, Goutallier grade, tear retraction, and tear size were quantified. One patient was lost to follow-up, and 99 patients completed MRI imaging.

In our cohort, 60% of patients reported subjective mechanical symptoms in the affected shoulder. Full-thickness rotator cuff tearing was identified in 42% of patients, any rotator cuff tearing in 69% of patients, and biceps long head subluxation in 14% of patients. Subjective mechanical symptoms were not associated with full-thickness rotator cuff tearing, any rotator cuff tearing, biceps long head subluxation, critical shoulder angle, Goutallier grade, tear size, or tear retraction. Older age was associated with full-thickness and any rotator cuff tearing. As a diagnostic test for full-thickness rotator cuff tearing, subjective shoulder mechanical symptoms has a sensitivity of 64%, a specificity of 44%, and Youden's index of 0.08, consistent with poor diagnostic accuracy.

Subjective mechanical symptoms in the affected shoulder are a common complaint in patients with suspected rotator cuff pathology. Patients may be reassured that a sensation of clicking or popping alone does not necessarily entail structural shoulder derangement.