Rotator cuff strength following open subscapularis tendon repair

Area of Science:

• Orthopedic Surgery
• Sports Medicine
• Shoulder Reconstruction

Background:

• Rotator cuff tears often involve both supraspinatus and subscapularis tendons.
• Understanding the functional outcomes after combined tears is crucial for surgical planning and patient expectations.

Purpose of the Study:

• To assess supraspinatus and subscapularis muscle strength after surgical repair of isolated or anterosuperior subscapularis tears.
• To identify factors influencing functional recovery following these specific rotator cuff repairs.

Main Methods:

• Open subscapularis repair in 24 patients (12 isolated, 12 anterosuperior tears).
• Clinical outcome assessment using UCLA, ASES, and Constant scores at an average of 40 months.
• Objective strength testing of subscapularis and supraspinatus using a spring gauge.
• Ultrasound evaluation of tendon integrity in 20 patients.

Main Results:

• Excellent clinical scores: average 27 UCLA, 77 ASES, 90% Constant.
• Good muscle strength recovery: subscapularis 92%, supraspinatus 90% of the contralateral shoulder.
• Significant reduction in supraspinatus strength observed specifically in the anterosuperior tear group.
• Ultrasound confirmed intact subscapularis tendons; 5 full-thickness and 1 partial-thickness supraspinatus re-tears noted.

Conclusions:

• Supraspinatus integrity, rather than subscapularis, is the primary determinant of outcomes in anterosuperior subscapularis tear repairs.
• Anterosuperior repairs are associated with a higher incidence of supraspinatus re-tears and diminished strength.
• Focusing on preserving and restoring supraspinatus function is critical for successful surgical outcomes in complex rotator cuff repairs.