Evan James Zucker MD, Presenter: Nothing to Disclose

Eric I Newman, Abstract Co-Author: Nothing to Disclose

Eric Wong MD, Abstract Co-Author: Nothing to Disclose

Shilpa Pandey MD, Abstract Co-Author: Nothing to Disclose

Jeffrey B. Driban PhD, Abstract Co-Author: Nothing to Disclose

Robert J. Ward MD, Abstract Co-Author: Nothing to Disclose

Masses compressing the axillary recess are seen in only a minority of patients with teres minor atrophy syndrome (TMA). The purpose of this research was to determine whether there is an association between "massless" TMA and capsular thickening.

This retrospective case-control study involved 22 cases of TMA (presence of teres minor fatty change on T1 weighted imaging or diffuse increased signal on water weighted sequences) in the absence of a compressive mass identified from 1040 consecutive shoulder MRI exams performed at our institution from January 2008 through February 2011 for all indications. For each case, an age/gender matched control without TMA was randomly selected from exams performed over this time period. The thickness of the glenohumeral joint capsule and the presence of capsular edema were determined. Capsular thickness was compared between cases and controls using the independent t-test, whereas the presence of capsular edema was compared using Fisher's exact test.

Mean +/- standard deviation capsular thickness (mm) for cases was 3.7 +/- 1.2 compared to 2.8 +/- 0.7 for controls, a difference which was statistically significant (t = -2.90; P = 0.007). There was no statistically significant difference in regards to the presence of capsular edema between cases and controls.

Isolated teres minor atrophy is associated with increased capsular thickness compared to age/gender matched controls. Capsular thickness may reflect previous capsulitis a potential etiology for secondary adhesions or fibrous bands that have been implicated in TMA.

Teres minor atrophy is associated with capsular thickening/capsulitis. Determining between causality and correlation is an area for further study.

Zucker, E, Newman, E, Wong, E, Pandey, S, Driban, J, Ward, R, Isolated Teres Minor Atrophy: Association with Capsular Thickening.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11010366.html