Lower Trapezius Tendon Transfer for Posterior-Superior Irreparable Rotator Cuff Tears: A Comprehensive Narrative Review

<h2>Abstract</h2> Lower trapezius tendon (LTT) transfer has emerged as an effective surgical treatment for posterior-superior irreparable rotator cuff tears (PSIRCTs), particularly in patients with compromised external rotation.²³ Initially used in paralytic shoulders ^{12, 18, 22}, LTT has gained popularity as a treatment option for irreparable rotator cuff tears due to its biomechanical similarity to the infraspinatus, making it an effective choice for restoring shoulder function.^{11, 32, 34} LTT's ability to reestablish shoulder stability, restore external rotation, and prevent humeral head migration sets it apart from other tendon transfers like latissimus dorsi (LD) transfer.³³ The procedure can be performed using an arthroscopically assisted technique, reducing invasiveness and preserving soft tissue.²¹ LTT is indicated for patients with PSIRCTs who have significant shoulder dysfunction, failed conservative treatments, and minimal glenohumeral arthritis. However, it is contraindicated in cases of advanced osteoarthritis. Clinical studies have shown improved range of motion, pain relief, and functional outcomes postoperatively.^{6, 7, 14, 15, 21, 23, 35, 43} Comparative studies also suggest superior results with LTT over LD transfers and superior capsular reconstruction (SCR).^{8, 10} As interest in joint-preserving procedures grows, LTT's role continues to expand, with refinements in surgical techniques and emerging innovations, such as the "parachute technique" and biologic augmentation, enhancing its efficacy.²⁰ This review examines LTT's biomechanics, clinical outcomes, comparative studies, and evolving innovations, highlighting its potential as a primary and salvage procedure for PSIRCTs.