The wrist is an anatomical junction where major blood vessels pass from the forearm into the hand, delivering oxygenated blood and nutrients. Because these vessels run close to the skin surface and over underlying bone, two main arteries are easily accessible for medical assessment. Feeling the pressure wave generated by the heart, known as the pulse, at the wrist provides a quick way to monitor a person’s cardiovascular status.
The Radial Artery
The most common location for checking a pulse is along the path of the radial artery. This vessel runs down the forearm and crosses the wrist on the side corresponding to the thumb. It is positioned superficially, lying just under the skin, making it accessible for palpation.
To feel the pulse, the index and middle fingers are placed gently in the groove between the tendon and the bone at the outer edge of the wrist. The radial artery crosses the distal end of the radius bone, which provides a firm structure against which the pulse can be compressed. This bony support makes the radial pulse the standard site for routine heart rate checks.
When checking the radial pulse, the examiner feels the expansion and recoil of the arterial wall as the heart pumps blood. Applying light pressure allows the examiner to count the rate, assess the rhythm, and determine the pulse volume.
The Ulnar Artery
The second major vessel supplying the wrist and hand is the ulnar artery, which travels along the opposite side of the forearm. This artery corresponds to the side of the wrist closest to the little finger. It originates from the brachial artery, running parallel to the radial artery along the medial aspect of the forearm.
The ulnar artery is less commonly used for routine pulse checks. At the wrist, it is situated deeper and is protected by surrounding muscle and tissue. This deeper course makes the pulse harder to locate and feel clearly.
Finding the ulnar pulse requires pressing slightly harder and further inward toward the center of the wrist. The artery passes near the pisiform bone before entering the hand. Despite its less frequent use, the ulnar artery plays a significant role in hand circulation.
How the Arteries Supply the Hand
The function of the radial and ulnar arteries is to ensure a continuous supply of blood to the entire hand. They achieve this by connecting and forming specialized structures called palmar arches once they enter the palm. This anatomical arrangement provides a dual blood supply, which creates redundancy.
The ulnar artery primarily contributes to the superficial palmar arch, which lies closer to the surface of the palm and supplies most of the fingers. The radial artery primarily dives deeper into the palm to form the deep palmar arch.
The superficial and deep arches are connected through smaller vessels called anastomoses. This extensive network ensures that if one main artery were blocked or injured, the other artery could still provide sufficient blood flow to the fingers and palm. This dual circulatory pathway protects the hand from lack of oxygenated blood.