VAN 121: Veterinary Gross Anatomy-II (2+2)

SUBSCAPULAR ARTERY

• It is a very large vessel as large as the brachial artery.
• It arises from the posterior face at the posterior border of the subscapularis muscle.
• It ascends in the space between the subscapularis and teres major along the medial face of the long head of triceps, then along the posterior border of the scapula to about its dorsal angle, turns round the border below this angle and terminates in the infraspinatus and deltoid.
• It supplies in its course branches to the teres major, subscapularis, caput longum, infraspinatus and deltoideus.
• Besides these, the subscapular artery gives off certain named branches such as:

Thoraco-dorsal artery

• The thoraco-dorsal artery is given off from the posterior face of the subscapular artery about an inch above its origin.
• It crosses the teres major, runs upwards and backwards on the deep face of the latissimus dorsi and is distributed to it.
• It also supplies a branch to the caput longum, a branch to the paniculus carnosus and the axillary lymph gland.

Posterior circumflex artery

• The posterior circumflex artery of the humerus arises from the subscapular artery from its anterior face passes downwards behind the shoulder joint in company with the axillary nerve and ramifies on the deep face of the deltoideus.
• It supplies branches to the deltoideus and teres minor and one of its branches accompanies the radial nerve and branches to all heads of triceps, brachialis, anconeus, extensor carpi radialis and cutaneous branch to the skin.

Circumflex artery

• The circumflex artery of the scapula arises from the anterior border of the subscapsularis, 2" or 3" above the shoulder joint.
• It divides into medial and lateral branches, which supply the subscapularis and infraspinatus.