Flexor carpi ulnaris muscle

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Flexor carpi ulnaris
Flexor carpi ulnaris.png
Dorsal (left) and ventral (right) views of deep muscles of the left forearm. The flexor carpi ulnaris muscle is in blue.
Details
Origin Medial epicondyle (common flexor tendon) and medial margin on olecranon of ulna
Insertion Pisiform, hook of the hamate, base of the fifth metacarpal bone (volar aspect)
Artery Ulnar artery
Nerve Muscular branches of ulnar nerve (from C8 and T1)
Actions Flexion and adduction of wrist
Antagonist Extensor carpi radialis brevis muscle and extensor carpi radialis longus muscle
Identifiers
Latin musculus flexor carpi ulnaris
TA98 A04.6.02.030
TA2 2483
FMA 38465
Anatomical terms of muscle

The flexor carpi ulnaris (FCU) is a muscle of the forearm that flexes and adducts at the wrist joint.

Contents

Structure

Origin

The flexor carpi ulnaris has two heads; a humeral head and ulnar head. The humeral head originates from the medial epicondyle of the humerus via the common flexor tendon. The ulnar head originates from the medial margin of the olecranon of the ulna and the upper two-thirds of the dorsal border of the ulna by an aponeurosis. Between the two heads passes the ulnar nerve and ulnar artery.

Insertion

The flexor carpi ulnaris inserts onto the pisiform, hook of the hamate (via the pisohamate ligament) and the anterior surface of the base of the fifth metacarpal (via the pisometacarpal ligament). [1]

Action

The flexor carpi ulnaris flexes and adducts at the wrist joint. [2]

Innervation

The flexor carpi ulnaris is innervated by the ulnar nerve. The corresponding spinal nerves are C8 and T1.

Tendon

The tendon of flexor carpi ulnaris can be seen on the anterior surface of the distal forearm. On a person's distal forearm, just before the wrist, there are either two or three tendons. The tendon of the flexor carpi ulnaris is the most medial (closest to the little finger) of these. The most lateral one is the tendon of flexor carpi radialis muscle, and the middle one, not always present, is the tendon of palmaris longus.

Function

The muscle, like all flexors of the forearm, can be strengthened by exercises that resist its flexion. A wrist roller can be used and wrist curls with dumbbells can also be performed. These exercises are used to prevent injury to the ulnar collateral ligament of elbow joint.[ citation needed ]

Variability

The muscle can be doubled as accessory flexor carpi ulnaris muscle and is often accompanied by concomitant variants. [3]

Clinical significance

Ulnar entrapment by the aponeurosis of the two heads of the flexor carpi ulnaris muscle may cause cubital tunnel syndrome.

The tendon of flexor carpi ulnaris can be used for tendon transfer. [3]

Additional images

Related Research Articles

<span class="mw-page-title-main">Carpal bones</span> Eight small bones that make up the wrist (or carpus) that connects the hand to the forearm

The carpal bones are the eight small bones that make up the wrist (carpus) that connects the hand to the forearm. The term "carpus" and "carpal" is derived from the Latin carpus and the Greek καρπός (karpós), meaning "wrist". In human anatomy, the main role of the carpal bones is to articulate with the radial and ulnar heads to form a highly mobile condyloid joint, to provide attachments for thenar and hypothenar muscles, and to form part of the rigid carpal tunnel which allows the median nerve and tendons of the anterior forearm muscles to be transmitted to the hand and fingers.

<span class="mw-page-title-main">Ulna</span> Medial bone from forearm

The ulna or ulnar bone is a long bone in the forearm stretching from the elbow to the wrist. It is on the same side of the forearm as the little finger, running parallel to the radius, the forearm's other long bone. Longer and thinner than the radius, the ulna is considered to be the smaller long bone of the lower arm. The corresponding bone in the lower leg is the fibula.

<span class="mw-page-title-main">Humerus</span> Long bone of the upper arm

The humerus is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a rounded head, a narrow neck, and two short processes. The body is cylindrical in its upper portion, and more prismatic below. The lower extremity consists of 2 epicondyles, 2 processes, and 3 fossae. As well as its true anatomical neck, the constriction below the greater and lesser tubercles of the humerus is referred to as its surgical neck due to its tendency to fracture, thus often becoming the focus of surgeons.

<span class="mw-page-title-main">Wrist</span> Part of the arm between the lower arm and the hand

In human anatomy, the wrist is variously defined as (1) the carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand; (2) the wrist joint or radiocarpal joint, the joint between the radius and the carpus and; (3) the anatomical region surrounding the carpus including the distal parts of the bones of the forearm and the proximal parts of the metacarpus or five metacarpal bones and the series of joints between these bones, thus referred to as wrist joints. This region also includes the carpal tunnel, the anatomical snuff box, bracelet lines, the flexor retinaculum, and the extensor retinaculum.

In human anatomy, extensor carpi radialis brevis is a muscle in the forearm that acts to extend and abduct the wrist. It is shorter and thicker than its namesake extensor carpi radialis longus which can be found above the proximal end of the extensor carpi radialis brevis.

In human anatomy, the extensor carpi ulnaris is a skeletal muscle located on the ulnar side of the forearm. The extensor carpi ulnaris acts to extend and adduct at the carpus/wrist from anatomical position.

<span class="mw-page-title-main">Flexor carpi radialis muscle</span> Superficial muscle in the anterior side of the forearm

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.

<span class="mw-page-title-main">Ulnar nerve</span> Nerve which runs near the ulna bone

The ulnar nerve is a nerve that runs near the ulna, one of the two long bones in the forearm. The ulnar collateral ligament of elbow joint is in relation with the ulnar nerve. The nerve is the largest in the human body unprotected by muscle or bone, so injury is common. This nerve is directly connected to the little finger, and the adjacent half of the ring finger, innervating the palmar aspect of these fingers, including both front and back of the tips, perhaps as far back as the fingernail beds.

<span class="mw-page-title-main">Metacarpal bones</span> Bones of hand

In human anatomy, the metacarpal bones or metacarpus, also known as the "palm bones", are the appendicular bones that form the intermediate part of the hand between the phalanges (fingers) and the carpal bones, which articulate with the forearm. The metacarpal bones are homologous to the metatarsal bones in the foot.

<span class="mw-page-title-main">Hamate bone</span> Carpal bone in the wrist

The hamate bone, or unciform bone, Latin os hamatum and occasionally abbreviated as just hamatum, is a bone in the human wrist readily distinguishable by its wedge shape and a hook-like process ("hamulus") projecting from its palmar surface.

<span class="mw-page-title-main">Radius (bone)</span> One of the two long bones of the forearm

The radius or radial bone is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The ulna is longer than the radius, but the radius is thicker. The radius is a long bone, prism-shaped and slightly curved longitudinally.

<span class="mw-page-title-main">Pisiform bone</span> Bone in the wrist

The pisiform bone, also spelled pisiforme, is a small knobbly, sesamoid bone that is found in the wrist. It forms the ulnar border of the carpal tunnel.

<span class="mw-page-title-main">Upper limb</span> Consists of the arm, forearm, and hand

The upper limbs or upper extremities are the forelimbs of an upright-postured tetrapod vertebrate, extending from the scapulae and clavicles down to and including the digits, including all the musculatures and ligaments involved with the shoulder, elbow, wrist and knuckle joints. In humans, each upper limb is divided into the arm, forearm and hand, and is primarily used for climbing, lifting and manipulating objects.

<span class="mw-page-title-main">Ulnar artery</span> Artery of the forearm

The ulnar artery is the main blood vessel, with oxygenated blood, of the medial aspects of the forearm. It arises from the brachial artery and terminates in the superficial palmar arch, which joins with the superficial branch of the radial artery. It is palpable on the anterior and medial aspect of the wrist.

The pronator teres is a muscle that, along with the pronator quadratus, serves to pronate the forearm. It has two origins, at the medial humeral supracondylar ridge and the ulnar tuberosity, and inserts near the middle of the radius.

<span class="mw-page-title-main">Carpometacarpal joint</span> Joint between the wrist and hand

The carpometacarpal (CMC) joints are five joints in the wrist that articulate the distal row of carpal bones and the proximal bases of the five metacarpal bones.

<span class="mw-page-title-main">Abductor digiti minimi muscle of hand</span> Muscle in the hypothenar compartment

In human anatomy, the abductor digiti minimi is a skeletal muscle situated on the ulnar border of the palm of the hand. It forms the ulnar border of the palm and its spindle-like shape defines the hypothenar eminence of the palm together with the skin, connective tissue, and fat surrounding it. Its main function is to pull the little finger away from the other fingers.

<span class="mw-page-title-main">Flexor retinaculum of the hand</span> Thickened fascia over the carpal tunnel

The flexor retinaculum 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.

<span class="mw-page-title-main">Intercarpal joints</span> Joints of the carpal bones of the wrist

The intercarpal joints can be subdivided into three sets of joints : Those of the proximal row of carpal bones, those of the distal row of carpal bones, and those of the two rows with each other.

<span class="mw-page-title-main">Extrinsic extensor muscles of the hand</span>

The extrinsic extensor muscles of the hand are located in the back of the forearm and have long tendons connecting them to bones in the hand, where they exert their action. Extrinsic denotes their location outside the hand. Extensor denotes their action which is to extend, or open flat, joints in the hand. They include the extensor carpi radialis longus (ECRL), extensor carpi radialis brevis (ECRB), extensor digitorum (ED), extensor digiti minimi (EDM), extensor carpi ulnaris (ECU), abductor pollicis longus (APL), extensor pollicis brevis (EPB), extensor pollicis longus (EPL), and extensor indicis (EI).

References

  1. Maroukis, Brianna L.; Ogawa, Takeshi; Rehim, Shady A.; Chung, Kevin C. (March 2015). "Guyon canal: the evolution of clinical anatomy". The Journal of Hand Surgery. 40 (3): 560–565. doi:10.1016/j.jhsa.2014.09.026. ISSN   1531-6564. PMC   4791630 . PMID   25446410.
  2. Chaudhry, Fatima; Ahmad, Haroon; Sinkler, Margaret A.; Arain, Abdul (2024), "Anatomy, Shoulder and Upper Limb, Forearm Compartments", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID   30969606 , retrieved 2024-08-21
  3. 1 2 Kunc, Vojtech; Stulpa, Michal; Feigl, Georg; Kachlik, David (2019-05-29). "Accessory flexor carpi ulnaris muscle with associated anterior interosseous artery variation: case report with the definition of a new type and review of concomitant variants". Surgical and Radiologic Anatomy. 41 (11): 1315–1318. doi:10.1007/s00276-019-02261-4. ISSN   0930-1038. PMID   31144008. S2CID   169032218.