Combined Lower Trapezius and Middle Trapezius Tendon Transfer for Posterior Superior Irreparable Rotator Cuff Tears: A Case Report.

INTRODUCTION: Irreparable rotator cuff tears (IRCTs) often deteriorate shoulder function, necessitating careful consideration of treatment approaches. While reverse total shoulder arthroplasty (RTSA) is the first line of treatment in patients with arthropathy, preserving the joint is crucial for highly demand patients without arthritis. For those patients, various tendon transfer techniques have been established to address different types of IRCTs, including lower trapezius tendon (LTT) transfer for posterior superior IRCTs (PSIRCTs) and middle trapezius tendon (MTT) transfer for isolated supraspinatus IRCTs (ISIRCTs).

CASE REPORT: A 66-year-old male with persistent right shoulder pain and weakness for 2 years, diagnosed with PSIRCTs, sought an alternative to RTSA due to occupational concerns as a restaurant owner. Preoperatively, patients showed limited range of motion (ROM) and weakness, especially in forward elevation (FE) and external rotation (ER). Radiography and magnetic resonance imaging (MRI) scan indicated superior humeral head translation without advanced arthritis and concurrent tears in the supraspinatus and infraspinatus with atrophy. After the consultation, patients underwent a combined transfer of LTT and MTT with a split Achilles tendon allograft in Y-configuration. By postoperative 1 year, the patient exhibited notable improvement, including reduced pain (VAS 4-2), enhanced function (ASES 50-83, Constant 42-78), and increased ROM (FE, 120°-160° and ER, 10°-40°). Radiographic assessments demonstrated an increased in acromiohumeral distance without arthritic progression. Post-operative MRI confirmed tendon integrity, and the patient successfully resumed work at 6 months.

CONCLUSION: A combined transfer of the MTT and LTT with a split Achilles tendon allograft in Y-configuration has been shown to alleviate pain, enhance functional scores, and improve the ROM in patients with PSIRCTs without arthritis.