The subscapularis Muscle is one of the four Rotator Cuff Muscles. It is the large one at the front of the Shoulder. It is the largest & strongest Cuff Muscle providing 53% of Total Cuff Strength.
The upper 60% of the insertion is tendinous and the lower 40% muscle.
It functions to turn the arm inwards and also helps in lifting movements, swimming and overhead activities.
Tears of the Subscapularis:
It tears less often than the other Rotator Group muscles, but when it does it causes dislocation of the biceps tendon from its groove. A person with a Subscapularis Tear will have pain at the front of the Shoulder and weakness with activities that involve forward lifting, twisting the arm inwards and sports.
The elderly and patients with very low demands do very well with Conservative Management Physiotherapy.
In young and active adults a mini-open repair of the Tendon is performed.