Soterios Gyftopoulos MD, Abstract Co-Author: Nothing to Disclose

Elizabeth Lee Carpenter MD, Presenter: Nothing to Disclose

Jonathan Khedoori Kazam MD, Abstract Co-Author: Nothing to Disclose

James S. Babb PhD, Abstract Co-Author: Nothing to Disclose

Jenny T. Bencardino MD, Abstract Co-Author: Nothing to Disclose

The purpose of this study is to determine if there is an association between subscapularis (SSc) tendon injury and a history of anterior shoulder dislocation.

A retrospective review of 50 consecutive MR (1.5/3T) studies of the shoulder was conducted via a computer data search of all studies performed at our institution during a 6 month period with a history of anterior shoulder dislocation (ASD). Twenty consecutive MR shoulder studies without a history of dislocation were also collected from the same period of time and used as a control group (C). Two readers reviewed each study independently and documented the presence and location (superior, central, and inferior) of SSC tendinosis and tearing (partial thickness (PT), full thickness (FT), and complete (CO)). In addition, any evidence of a Hill-Sachs deformity (HS), osseous Bankart injury (OB), and anterior/anteroinferior labral (AL) tear was documented. Statistical analysis included Fisher exact and kappa coefficient tests.

Excellent interobserver agreement was found for AL tear (0.83), OB (0.64) and HS (0.77). Moderate interobserver agreement was found for SSc FT tear (0.55), SSc PT tear (0.58) and SSc tendinosis (0.44). SSc tendinosis and tearing were more prevalent in all locations in the ASD group compared to the C group. Statistically significant associations for reader 1 were found between SSc PT tear and AL tear (p=0.0129), SSc PT tear and HS (p=0.0158), SSc tendinosis and AL tear (p=0.029) and SSc tendinosis and HS (p=0.0330). Statistically significant differences were found between the ASD and C groups for the presence of tendinosis (p= 0.0025) and tearing (p= 0.0135) in the inferior subscapularis tendon. Significant associations were found between the presence of tendinosis and tearing in the inferior and central portions of the SSc tendon and HS and AL tears for both readers (Table 1). When SSc tendinosis and/or tearing were found in the central and inferior portions of the SSc tendon, the patient was more likely to have HS, OB, and AL tear.

There is a significant association between pathology in the central and inferior portions of the subscapularis tendon and prior anterior shoulder dislocation.

Subscapularis tendon injury is a frequent, often overlooked, finding in patients with anterior shoulder dislocation that can predispose to shoulder instability, pain, and functional impairment.

Gyftopoulos, S, Carpenter, E, Kazam, J, Babb, J, Bencardino, J, MR Imaging of Subscapularis Tendon Injury in the Setting of Anterior Shoulder Dislocation.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11003177.html