Arthroscopic Management of Selective Loss of External Rotation After Surgical Stabilization of Traumatic Anterior Glenohumeral Instability: Arthroscopic Restoration of Anterior Transverse Sliding Procedure

Purpose: The purpose of this study was to clarify the effectiveness of an arthroscopic procedure for restoration of anterior transverse sliding (RATS) mechanism of the subscapularis tendon in patients with loss of external rotation after surgical stabilization of anterior glenohumeral instability. Methods: Seven patients who underwent an arthroscopic RATS procedure for loss of external rotation after surgical stabilization of anterior glenohumeral instability were retrospectively reviewed. There were 4 male and 3 female patients with a mean age of 30.7 years. The original procedure was arthroscopic Bankart repair and rotator interval closure in 5 patients, open Bankart repair in 1, and an open Bristow procedure in 1. The arthroscopic RATS procedure was performed as follows: (1) removal of the fibrous tissue in the rotator interval; (2) release of the subscapularis tendon from the glenoid neck; and (3) incision of the superior part of the inferior glenohumeral ligament until a sufficient external rotation angle was obtained without causing anterior instability. We evaluated the mean forward flexion and external and internal rotation angles, Constant score, and University of California, Los Angeles score before the arthroscopic RATS procedure and at final follow-up (mean, 24 months). Results: The mean forward flexion and external and internal rotation angles improved from 162.1 degrees +/- 9.5 degrees to 171.4 degrees +/- 3.8 degrees (P < .05), from 2.9 degrees +/- 4.9 degrees to 47.9 degrees +/- 9.1 degrees (P < .005), and from T10 to T8 (P < .05), respectively. The mean Constant and University of California, Los Angeles scores improved from 81.0 +/- 13.6 points to 95.1 +/- 4.0 points and from 24.0 +/- 3.7 points to 33.9 +/- 2.0 points, respectively (P < .005). Conclusions: The arthroscopic RATS mechanism procedure is a useful treatment option with minimum morbidity in patients with loss of external rotation after surgical stabilization of traumatic anterior glenohumeral instability. Level of Evidence: Level IV, therapeutic case series.