Conjoined Tendon of the Coracoid

tendo conjunctus coracoidi

The conjoined tendon of the coracoid is the common tendinous origin of the short head of the biceps brachii and the coracobrachialis muscle from the apex of the coracoid process. The two muscles arise from a single tendinous attachment, descend together in the medial arm, and then diverge — coracobrachialis inserts on the humerus, short head biceps continues to the radial tuberosity. The conjoined tendon is the landmark for the subcoracoid (anterior) approach to the shoulder.

Region: Shoulder

Clinical Relevance

Clinical Notes

The conjoined tendon is the critical retraction structure in anterior shoulder approaches. In the deltopectoral approach, medial retraction of the conjoined tendon exposes the subscapularis and the anterior capsule; excessive medial retraction risks the musculocutaneous nerve where it enters the coracobrachialis muscle 5-8 cm below the coracoid. In arthroscopic coracoid decompression for subcoracoid impingement, the coracoid tip where the conjoined tendon attaches is the landmark for impingement between the subscapularis and coracoid. SLAP type II tears involve the long head biceps superior labrum anchor, distinct from the conjoined tendon.

Pathology

Common Injuries & Conditions

Musculocutaneous Nerve Risk in Conjoined Tendon Retraction

Excessive medial retraction of the conjoined tendon in the deltopectoral approach to the shoulder risks the musculocutaneous nerve entering the coracobrachialis 5-8 cm below the coracoid tip; gentle retraction with the arm in slight flexion and adduction reduces retraction tension and protects the nerve during subscapularis exposure.