Lower Trapezius Transfer: Technical Tips for Tendon Harvesting and Arthroscopic Achilles Allograft Fixation.

Arthroscopy-assisted lower trapezius transfer is increasingly recognized as a standard approach for addressing irreparable posterosuperior rotator cuff tears. A posterior incision is made along the medial margin of the scapula to identify and dissect the lower trapezius. The Achilles allograft is arthroscopically fixed to the greater tuberosity with a knotless double-row "transosseous-equivalent" repair and to the trapezius using Pulver-Taft technique sutures. The arm should remain immobilized in abduction and neutral rotation for 6 weeks. This procedure enables a dynamic tendon transfer, restoring torque biomechanics and normalizing glenohumeral joint function.