The Influence of Repairing the Sub-scapularis on Outcomes After Reverse Arthroplasty

Overview

The study is a prospective, multi-center, randomized blinded study to determine how repairing the subscapularis vs. not repairing the subscapularis when subjects are implanted with the AltiVate Reverse® Shoulder System for reverse total shoulder arthroplasty affects isometric and isokinetic internal rotational strength. It is hypothesized that patients in which the subscapularis is repaired will have improved postoperative isometric and isokinetic internal rotational strength.

Reverse shoulder arthroplasty (RSA) is performed to provide improvement in pain relief and restoration of function in patients with rotator cuff tear arthropathy and massive irreparable rotator cuff tears . Traditional total shoulder designs failed to address the unique mechanics of shoulders with deficient rotator cuffs. Different prosthesis designs exist for RSA, all of which increase the deltoid lever arm to provide a stable fulcrum for active elevation in a rotator cuff deficient shoulder. The Reverse® Shoulder Prosthesis (RSP®) (DJO Surgical) sought to address issues correlated to the Grammont design by lateralizing the center of rotation as well as utilizing a central compressive screw with a 5.0-mm peripheral locking screws for fixation and a glenosphere . Despite the success of the lateralized design, the effect of the repair of the subscapularis tendon during RSA on shoulder strength, range of motion, and shoulder function remains inconclusive. The rationale for repairing the subscapularis during RSA include anatomic preservation of a functioning rotator cuff muscle, an increased potential for internal rotation, better joint protection, and more stability. The reasoning for not repairing the subscapularis include that it may be biomechanically unfavorable for both the deltoid and the posterior rotator cuff, limiting the range of motion. As such, this randomized study aims to address if subscapularis repair impacts isometric and isokinetic internal rotational strength, with shoulder function and complications as secondary objectives, when patients are implanted with the AltiVate Reverse® device. The study will take place at multiple sites across the United States and will be managed by the DJO Surgical Clinical Affairs Department.

Conditions

Interventions

Eligibility

Locations (4)

Outcomes