Anterior capsular shift volume reduction: an in vitro comparison of 3 techniques.

The anterior capsular shift is a well-established procedure for correction of capsular redundancy. Several different techniques have been developed to reduce capsular volume via a shift or capsulorrhaphy. The purpose of this study was to compare volume reduction objectively among 3 popular capsular shift techniques. Twenty-four fresh-frozen human cadaver shoulders were assigned to one of three groups: a lateral (humeral)-based T-capsular shift (group A), a medial (glenoid)-based T-capsular shift (group B), or a central vertical capsular shift (group C). Initial capsular volume was measured by repeated injection of a viscous fatty acid sulfate solution and recorded for each specimen. A predetermined capsular shift procedure was performed on each cadaver, and repeated measurements were made. All 3 procedures resulted in a significant reduction in capsular volume. The lateral (humeral)-based T-capsular shift resulted in the most reduction (48.9%). This reduction was statistically greater than for the glenoid-based shift (36.8% volume reduction) and approached statistical significance for the vertical shift (40.3% volume reduction, P =.12). Repeated measurements confirmed that the injection technique was valid and reproducible. The lateral (humeral)-based capsular shift results in the most volume reduction and should be considered the preferred procedure for patients with excessive capsular redundancy.