Pectoralis minor tendon transfer for irreparable anterosuperior cuff tears

Tears of the subscapularis tendon are a frequent cause of shoulder dysfunction. Tendon transfer techniques have been devised to treat irreparable tears. The objectives of this study were to explore the anatomic feasibility of using the pectoralis minor tendon as a graft for subscapularis tendon tears, the safety of the procedure, and the scope of this approach in improving shoulder function.

We performed open pectoralis minor transfer in 27 patients (22 men; mean age, 60 years) with irreparable tears of the upper two-thirds of the subscapularis tendon, grade III fatty degeneration, and irreparable supraspinatus tears. Constant and Simple Shoulder Test scores and functional outcomes were evaluated at 3, 12, and 24 months. All patients were available for follow-up.

The pectoralis minor tendon easily reached the subscapularis footprint. There were no cases of musculocutaneous nerve or brachial plexus injury or graft failure. Active forward flexion improved from 127° to 177°; external rotation with the arm at the side declined by 11°. The Simple Shoulder Test score improved by 5 points and the Constant score by 41 points, although the strength subscore did not rise significantly.

This study showed that it is anatomically feasible to use the pectoralis minor tendon as a graft to treat upper subscapularis lesions; the procedure is safe in terms of brachial plexus and musculocutaneous nerve injury; and pectoralis minor transfer can improve shoulder function and provide pain relief in patients with Lafosse grade III subscapularis tears, likely through a tenodesis effect, even in the presence of irreparable supraspinatus tears.