Clinical, Radiographic, and Surgical Presentation of Subscapularis Tendon Tears: A Retrospective Analysis of 139 Patients

Purpose: To analyze and correlate the clinical, radiographic, and surgical presentation of subscapularis (SSc) tears treated with arthroscopic repair. Methods: We retrospectively identified 455 patients who underwent rotator cuff tear repairs at our institution from 2010 to 2014. Of these patients, 139 underwent an SSc repair either in isolation or concurrently with other rotator cuff procedures. Tear size was classified arthroscopically by whether tears involved the superior one-third of the SSc tendon, superior two-thirds of the SSc tendon, or complete SSc tendon. Patient demographic characteristics, assessments of belly-press weakness and the lift-off test, magnetic resonance imaging (MRI) findings, and data on concurrent supraspinatus and biceps tendon pathology were collected and analyzed according to tear size. Results: Our cohort had a mean age of 61.8 +/- 12.5 years, with a male-female gender ratio of 1.7:1. There were 22 tears of the superior one-third of the SSc (16%), 96 t ears of the superior two-thirds of the SSc (69%), and 21 complete SSc tears (15%). Overall, MRI diagnosis of SSc tears had a sensitivity of 83% and specificity of 70%. MRI sensitivity was associated with tear severity (P = .02), with complete tears having an MRI sensitivity of 100%; superior two-thirds, 82%; and superior one-third, 67%. Physical examination sensitivity for belly-press weakness and the lift-off test was 61% and 63%, respectively, and did not correspond with tear size. Increased SSc tear size corresponded with a history of trauma (P = .04) and the presence of concurrent supraspinatus tears (P = .03) and biceps pathology (P = .003). Conclusions: The diagnosis of SSc tears remains challenging because of the limited sensitivity of MRI and physical examination. The diagnostic sensitivity of MRI is associated with SSc tear size, whereas physical examination is independent of tear size. Additional associations identified in this study include increased SSc tear size corresponding with a history of trauma, presence of concurrent supraspinatus tears, and presence of concurrent biceps tendon pathology. Level of Evidence: Level III, retrospective comparative study.