Blood Vessels of 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.