Blood vessels are multi-layered tubes to take blood from the heart in thicker, higher pressure arteries and back to the heart in thinner, flexible and lower-pressure veins.
The subclavian artery is the large vessel that begins the blood supply to the upper extremity. It begins near the heart and travels under the clavicle bone toward the shoulder. It gives off several small branches before continuing on as the axillary artery.
Blood travels from the heart into the subclavian artery which continues on down the arm as the axillary artery. The axillary artery travels deep in the arm pit and gives off several small branches which feed muscles and bones around the shoulder. The axillary artery continues down the arm as the brachial artery.
The brachial artery is a blood supply vessel and is a continuation of the axillary artery. It begins under the pectoralis muscle and travels down the arm before splitting into two arteries (the radial artery and the ulnar artery) at the elbow.
The radial artery is one of two major blood vessels that supply blood to the forearm and hand. The radial artery comes from the brachial artery and travels across the front of the elbow. In the forearm, it travels deep under muscle until it comes closer to the skin surface near the wrist. You can feel the pulse of the radial artery just under the skin on the thumb side of the wrist. After it travels across the wrist, the radial artery branches to form a network of blood supply vessels in the hand. One of these vessels is called the deep palmar arch.
The ulnar artery is one of two major blood vessels that supply blood to the forearm and hand. The ulnar artery comes from the brachial artery and travels across the front of the elbow. In the forearm, it travels deep under muscle along the small finger side of the forearm. After it travels across the wrist, the ulnar artery branches to form a network of blood supply vessels in the hand. One of these vessels is called the superficial palmar arch.
Deep Palmar Arch
As the radial artery continues in the hand, it wraps around the thumb and comes across the deep palm. This vessel, which resembles the shape of an arch, is called the deep palmar arch. This small but important vessel sends off small branches to supply blood to the thumb and index finger. It also connects to the superficial palmar arch in most people.
Superficial Palmar Arch
As the ulnar artery continues in the hand, it travels across the palm. The vessel creates the shape of an arch, and is called the superficial palmar arch. This vessel communicates with the deep palmar arch and also gives off important branches which supply blood to the fingers. These are called the common digital arteries.
Common Digital Arteries
The common digital arteries are small vessels that come from the palmar arches and supply blood to the fingers. They are called “common” because most of these vessels travel in the palm toward the fingers and then split to provide blood to two different fingers. The splits, which occur in the palm, become the proper digital arteries to the fingers.
Digital Arteries to the Thumb
The thumb receives its blood supply from the digital arteries to the thumb. The largest of these is a branch from the deep palmar arch and is called the “princeps pollicis” artery.
Proper Digital Arteries to the Fingers
As the common digital arteries travel from the palm toward the fingers, they split near the finger web spaces to become the proper digital arteries. The split feeds two different fingers. For example, the common digital artery that travels in the palm between the middle and ring fingers splits and then gives one vessel to the ring finger and one vessel to the middle finger. Each finger has two proper digital arteries that run on either side along its length. If one of these vessels is injured, the several connections between these two proper digital arteries usually maintain the blood supply to the entire finger.
Radial Artery of the Index finger
Near the digital artery to the thumb, the radial artery to the index finger branches off of the deep palmar arch. It brings blood supply to the index finger along its thumb side. The other side (ulnar side) of the index finger is supplied by a branch of a common digital artery.