Subscapularis Tendon
Anatomy
Key Anatomical Features:
- Arises from the undersurface of the scapula
- Multi-pennate muscle
- Tendon passes beneath the coracoid process and deep to the pectoralis
- Contributes fibres to rotator sling and supraspinatus insertion
- Upper border forms part of anterior interval
Injuries
Common Injury Patterns:
- Tears are most common in association with advanced cuff disease
- Subscapularis tendinopathy is more common at the superior border
- Tears may be associated with subluxation of the biceps tendon
- If a tear involves the interval only, the displaced biceps tendon will lie above the subscapular tendon
- If there is a more significant injury, the biceps tendon lies against the humeral head
Uncommon Cause - Coracoid Impingement:
An uncommon cause of tendinopathy is impingement deep to a prominent coracoid process. In these patients, the coracoid process is usually elongated and the distance between its tip and the underlying humeral head is less than 9 mm.
An uncommon cause of tendinopathy is impingement deep to a prominent coracoid process. In these patients, the coracoid process is usually elongated and the distance between its tip and the underlying humeral head is less than 9 mm.