Clinical Outcomes of Staged Bilateral Middle Trapezius Transfer for Irreparable Supraspinatus Tendon Tears: A Case Report.

Introduction: Middle trapezius tendon (MTT) transfer has recently emerged as a joint-preserving treatment option for irreparable supraspinatus tears (IST), demonstrating favorable clinical outcomes in carefully selected patients. However, clinical outcomes following staged bilateral MTT transfer have not previously been reported. This case report describes the clinical and structural outcomes of two patients who underwent staged bilateral MTT transfer for bilateral ISTs. Case Report: Two patients (four shoulders) with bilateral symptomatic ISTs underwent staged arthroscopic-assisted MTT transfer. Clinical outcomes were assessed using the Visual Analog Scale, single assessment numeric evaluation, constant score, American Shoulder and Elbow Surgeons score, range of motion (ROM), and shoulder muscle strength. Structural integrity was evaluated using post-operative magnetic resonance imaging (MRI). At final follow-up (mean, 27.5 months), three of four shoulders demonstrated substantial improvements in pain, functional scores, ROM, and muscle strength with intact tendon healing on MRI. One shoulder developed partial retear, resulting in limited functional improvement, whereas the contralateral shoulder of the same patient achieved satisfactory clinical and structural outcomes. Conclusion: Staged bilateral MTT transfer may be a feasible joint-preserving treatment option for selected patients with bilateral ISTs. Favorable clinical and structural outcomes were achieved in three of four shoulders, with substantial improvements in pain, shoulder function, ROM, and muscle strength. Partial retear in one shoulder did not preclude successful reconstruction of the contralateral shoulder. Further studies with larger cohorts and longer follow-up are warranted to establish the reproducibility and long-term durability of bilateral MTT transfer. Level of Evidence: IV; Case report.