Ulnar artery

The ulnar artery (a. Ulnaris) is, as it were, an extension of the brachial artery, from which it extends in the ulnar fossa at the level of the coronoid process of the ulna. Then on the way to the brush the artery goes under the round pronator, giving to it the muscle branches. Further, the artery, accompanied by the ulnar nerve, passes distally between the superficial and deep flexors of the fingers. Through the gap in the medial part of the flexor retainer and under the muscles of the pinky's elevation, the ulnar artery penetrates into the palm. Here she anastomoses with the superficial palmar branch of the radial artery, forming a superficial palmar arc (arcus palmaris superficialis).

The following branches extend from the ulnar artery:

1. Muscle branches (rr. Musculares) go to the muscles of the forearm;
2. the ulnar recurrent artery (a.recurrens ulnaris) departs from the beginning of the ulnar artery and divides into the anterior and posterior branches. A larger anterior branch is sent proximally into the medial anterior elbow groove and anastomizes here with the lower ulnar collateral artery, a branch of the brachial artery. The posterior branch follows the back surface of the elbow joint and anastomoses in the medial posterior ulnar groove with the superior ulnar collateral artery - the branch of the brachial artery;
3. the common interosseous artery (a. Interossea communis) departs from the ulnar artery at the level of tuberosity of the radius. This is a short trunk that follows the interosseous membrane and divides into the anterior and posterior interosseous arteries. The anterior interosseous artery (a. Interossea anterior) along the anterior surface of the interosseous membrane is guided to the proximal edge of the muscle - a square pronator, which gives the branch to the palmar wrist network. Then the artery perforates the membrane and takes part in the formation of the back wrist network. On the forearm, she gives the artery that accompanies the median nerve (a. Comitans nervi mediani). The posterior interosseous artery (a. Interossea posterior) immediately perforates the interosseous membrane and follows in the distal direction between the extensors of the forearm. A recurrent interosseous artery (a. Interossea recurrens) that rises under the lateral tendon bundles of the triceps arm muscle to the lateral posterior ulnar fissure, where it anastomizes with the middle collateral artery from the deep artery of the shoulder and, like all return arteries, participates in the formation of the elbow articular network. By the end branches, the posterior interosseous artery is anastomosed with the anterior interosseous artery and with the dorsal carpal branches (from the ulnar and radial arteries), takes part in the formation of the rear wrist network, from which the above-described dorsal metacarpal arteries depart;
4. The palmar carpal branch (r. Carpalis palmaris) departs from the ulnar artery at the level of the styloid process of the ulna and together with the palmar metacarpal branch from the radial artery and the branch from the anterior interosseous artery participates in the formation of the palmar network of the wrist from which these joints are supplied;
5. the dorsal carpal branch (r. Carpalis dorsalis) starts from the ulnar artery at the same level as the palmar carpal branch, then goes to the rear of the hand under the tendon of the elbow flexor of the hand, also participates in the formation of the palmar wrist network.
6. the deep palmar branch (r. Palmaris profundus) departs from the ulnar artery near the pea-bones, perforates the muscle that opposes the little finger, and blood supply to the muscles of the pinky and the skin over the little finger. As noted, the end section of the ulnar artery together with the superficial palmar branch of the radial artery forms a superficial palmar arc. From this arch, the common palmar arteries (aa. Digitales palmares communes), and from them - their own digital arteries (aa., Digitales palmares propriae), moving to adjacent sides of neighboring fingers.

For the upper extremities, the presence of anastomoses in the subclavian, axillary, brachial, radial and ulnar arteries, which provide a collateral flow of arterial blood and blood supply to the joints, is characteristic.