The ulnar artery is the main

blood vessel The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away ...

, with oxygenated

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the c ...

, of the medial aspects of the

forearm The forearm is the region of the upper limb between the elbow and the wrist. The term forearm is used in anatomy to distinguish it from the arm, a word which is most often used to describe the entire appendage of the upper limb, but which in ...

. It arises from the

brachial artery The brachial artery is the major blood vessel of the (upper) arm. It is the continuation of the axillary artery beyond the lower margin of teres major muscle. It continues down the ventral surface of the arm until it reaches the cubital fossa ...

and terminates in the superficial palmar arch, which joins with the superficial branch of the

radial artery In human anatomy, the radial artery is the main artery of the lateral aspect of the forearm. Structure The radial artery arises from the bifurcation of the brachial artery in the antecubital fossa. It runs distally on the anterior part of the f ...

. It is palpable on the anterior and medial aspect of the

wrist In human anatomy, the wrist is variously defined as (1) the Carpal bones, carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand; "The wrist contains eight bones, roughly aligned in two rows, known ...

. Along its course, it is accompanied by a similarly named

vein Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated b ...

or veins, the

ulnar vein In anatomy, the ulnar veins are venae comitantes for the ulnar artery. They mostly drain the medial aspect of the forearm. They arise in the hand and terminate when they join the radial veins to form the brachial veins. They follow the same c ...

or ulnar veins. The ulnar artery, the larger of the two terminal branches of the brachial, begins a little below the bend of the

elbow The elbow is the region between the arm and the forearm that surrounds the elbow joint. The elbow includes prominent landmarks such as the olecranon, the cubital fossa (also called the chelidon, or the elbow pit), and the lateral and the media ...

in the

cubital fossa The cubital fossa, chelidon, or elbow pit, is the triangular area on the anterior side of the upper limb between the arm and forearm of a human or other hominid animals. It lies anteriorly to the elbow (Latin ) when in standard anatomical position ...

, and, passing obliquely downward, reaches the ulnar side of the forearm at a point about midway between the elbow and the wrist. It then runs along the ulnar border to the wrist, crosses the transverse carpal ligament on the radial side of the

pisiform bone The pisiform bone ( or ), also spelled pisiforme (from the Latin ''pisifomis'', pea-shaped), is a small knobbly, sesamoid bone that is found in the wrist. It forms the ulnar border of the carpal tunnel. Structure The pisiform is a sesamoid bone, ...

, and immediately beyond this bone divides into two branches, which enter into the formation of the

superficial Superficial may refer to: *Superficial anatomy, is the study of the external features of the body *Superficiality, the discourses in philosophy regarding social relation *Superficial charm, the tendency to be smooth, engaging, charming, slick and ...

and

deep Deep or The Deep may refer to: Places United States * Deep Creek (Appomattox River tributary), Virginia * Deep Creek (Great Salt Lake), Idaho and Utah * Deep Creek (Mahantango Creek tributary), Pennsylvania * Deep Creek (Mojave River tributary), ...

volar arches.

Branches

Forearm:

Anterior ulnar recurrent artery The anterior ulnar recurrent artery is an artery in the forearm. It is one of two recurrent arteries that arises from the ulnar artery, the other being the posterior ulnar recurrent artery. It arises from the ulnar artery immediately below the el ...

Posterior ulnar recurrent artery The posterior ulnar recurrent artery is an artery in the forearm. It is one of two recurrent arteries that arises from the ulnar artery, the other being the anterior ulnar recurrent artery. The posterior ulnar recurrent artery being much larger t ...

Common interosseous The common interosseous artery, about 1 cm. in length, arises immediately below the tuberosity of the radius from the ulnar artery. Passing backward to the upper border of the interosseous membrane An interosseous membrane is a thick den ...

is very short, around 1 cm, and gives rise to the anterior, posterior, and recurrent interosseous arteries and close to the wrist it gives off the palmar carpal branch which is the ulnar contribution to the

palmar carpal arch The palmar carpal arch is the combination ( anastomosis) of two arteries: the Palmar carpal branch of radial artery and the palmar carpal branch of ulnar artery. This anastomosis is joined by a branch from the anterior interosseous artery abov ...

and it also gives a dorsal carpal branch which is the ulnar contribution to

dorsal carpal arch The dorsal carpal arch (dorsal carpal network, posterior carpal arch) is an anatomical term for the combination ( anastomosis) of dorsal carpal branch of the radial artery and the dorsal carpal branch of the ulnar artery near the back of the wris ...

. Hand: Deep palmar branch of ulnar artery which passes through the hypothenar muscles to anastomose with the

deep palmar arch The deep palmar arch (deep volar arch) is an arterial network found in the palm. It is usually primarily formed from the terminal part of the radial artery. The ulnar artery also contributes through an anastomosis. This is in contrast to the supe ...

which is formed predominantly by the

and the terminal branch of the ulnar artery is then to form the superficial palmar arch.

Relations

In its upper half, it is deeply seated, being covered by the Pronator teres,

Flexor carpi radialis In anatomy, flexor carpi radialis is a muscle of the human forearm that acts to flex and (radially) abduct the hand. The Latin ''carpus'' means wrist; hence flexor carpi is a flexor of the wrist. Origin and insertion The flexor carpi radialis is ...

Palmaris longus The palmaris longus is a muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much long ...

, and

Flexor digitorum superficialis Flexor digitorum superficialis (''flexor digitorum sublimis'') is an extrinsic flexor muscle of the fingers at the proximal interphalangeal joints. It is in the anterior compartment of the forearm. It is sometimes considered to be the deepest pa ...

; it lies upon the Brachialis and

Flexor digitorum profundus The flexor digitorum profundus is a muscle in the forearm of humans that flexes the fingers (also known as digits). It is considered an extrinsic hand muscle because it acts on the hand while its muscle belly is located in the forearm. Together ...

. The

median nerve The median nerve is a nerve in humans and other animals in the upper limb. It is one of the five main nerves originating from the brachial plexus. The median nerve originates from the lateral and medial cords of the brachial plexus, and has cont ...

is in relation with the medial side of the artery for about 2.5 cm. and then crosses the vessel, being separated from it by the ulnar head of the Pronator teres. In the lower half of the forearm it lies upon the

, being covered by the integument and the superficial and deep fasciæ, and placed between the

Flexor carpi ulnaris The flexor carpi ulnaris (FCU) is a muscle of the forearm that flexes and adducts at the wrist joint. Structure Origin The flexor carpi ulnaris has two heads; a humeral head and ulnar head. The humeral head originates from the medial epicondyle of ...

and

. It is accompanied by two venæ comitantes, and is overlapped in its middle third by the

; the ulnar nerve lies on the medial side of the lower two-thirds of the artery, and the palmar cutaneous branch of the nerve descends on the lower part of the vessel to the palm of the hand.

Wrist

At the wrist the ulnar artery is covered by the integument and the volar carpal ligament, and lies upon the

Flexor retinaculum of the hand The flexor retinaculum (transverse carpal ligament, or anterior annular ligament) is a fibrous band on the palmar side of the hand near the wrist. It arches over the carpal bones of the hands, covering them and forming the carpal tunnel. Structu ...

. On its medial side is the

, and, somewhat behind the artery, the ulnar nerve.

Peculiarities

The ulnar artery varies in its origin in the proportion of about one in thirteen cases; it may arise about 5 to 7 cm. below the elbow, but more frequently higher, the brachial being more often the source of origin than the axillary. Variations in the position of this vessel are more common than in the radial. When its origin is normal, the course of the vessel is rarely changed. When it arises high up, it is almost invariably superficial to the Flexor muscles in the forearm, lying commonly beneath the fascia, more rarely between the fascia and integument. In a few cases, its position is subcutaneous in the upper part of the forearm, and subaponeurotic in the lower part.

Additional images

File:Gray417_color.PNG, Cross-section through the middle of the forearm. File:Gray421.png, Transverse section across distal ends of radius and ulna. File:Gray422.png, Transverse section across the wrist and digits. File:Gray425.png, The palmar aponeurosis. File:Gray526.png, Diagram of the anastomosis around the elbow-joint. File:Gray527.png, Arteries of the right forearm - anterior view. File:Gray528.png, Ulnar and radial arteries. Deep view.

References

External links

* * {{Authority control Arteries of the upper limb