Blood Vessels

Blood Vessels of the Upper Limbs

Blood Vessels of Upper Limbs

The subclavian arteries deliver blood to the upper limbs.

The upper limbs' arterial blood supply begins with the subclavian artery, which changes names along its path to the axillary (in the armpit area) and the brachial (along the humerus). The subclavian artery moves between the clavicle and first rib from the aorta. Branches split to the thoracic region before and after it becomes the axillary artery. The axillary artery is the continuation of the subclavian artery extending through the axillary region and ending at the neck of the humerus. Here, a branch forms the humeral circumflex artery, providing blood to the shoulder and the deltoid muscle. The brachial artery continues from here, from the humerus's medial side to behind the elbow, supplying blood to muscles. The brachial is the artery typically measured for blood pressure. The deep brachial, ulnar recurrent, and radial recurrent arteries arise from the brachial to supply the triceps brachii muscle, elbow joint, and forearm muscles.

In the forearm the brachial artery divides into radial and ulnar arteries, which move along the radius and ulna bones, respectively. Anterior and posterior interosseous arteries arise from the ulnar artery and move between radius and ulna. The radial artery supplies the wrist, index finger, thumb, and lateral forearm muscles. The ulnar artery supplies medial forearm muscles, index finger, and digits 3–5. Interosseous muscles supply deep flexor and extensor muscles. At the wrist, ulnar and radial arteries form two palmar arches, which further split into the hand's palmar metacarpal arteries and fingers' palmar digital arteries.

Arteries of Upper Limbs

The blood supply for the upper limbs originates with the subclavian artery, which becomes the axillary and brachial arteries. Several branches arise to distribute blood throughout the arm.
Blood in the arms drains from deep veins through the subclavian vein, in a reverse of the path taken by arteries. In the hand and forearm, palmar digital and metacarpal veins move blood from palmar arches up through the radial and ulnar veins. These unite at the elbow into the brachial vein, which in turn merges with basilic veins to form the axillary vein. The axillary vein continues into the subclavian vein into the shoulder. Superficial veins in upper limbs are larger than deep veins and easily seen. The dorsal venous network on the back of the hand drains blood into the forearm's cephalic and basilic veins. The basilic moves up the radius and beyond, to merge with the brachial vein and form the axillary vein at the axilla (armpit). The median cubital vein connects the cephalic and basilic veins and is a common site of blood draws. The median antebrachial vein moves up from the thumb's base through the forearm, emptying at the elbow into either the cephalic or basilic vein.

Veins of Upper Limbs

Blood in upper limbs drains through many deep and superficial veins, all of which eventually merge to empty into the subclavian vein.