The chief action of abductor pollicis longus is to abduct the thumb at the carpometacarpal joint, thereby moving the thumb anteriorly. By its continued action it helps to abduct the wrist radial deviation and flex the hand the apl insertion on the trapezium and the apb origin on the same bone is the only connection between the. Along with extensor pollicis longus, it is responsible for extension of the thumb. The main function of abductor pollicis brevis is the abduction of the thumb at the carpometacarpal joint.
The extensor pollicis brevis originates from the posterior surface of the radius and the interosseous membrane of the forearm. View or download all content the institution has subscribed to. Superficial palmar branch of the radial artery the medical illustrations contained in this online atlas are. Flexes the interphalangeal joint and metacarpophalangeal joint of the thumb. Extends the thumb mcp joint and weakly abducts the thumb basal joint, along with other muscles which produce radial and. Recurrent branch of median nerve c8 and t1 arterial supply. Draws 1st metacarpal laterally to oppose thumb toward center of palm and rotates it medially innervation.
Extensor pollicis longus muscle wikipedia republished. It arises from the lateral part of the middle third of the dorsal surface of the body of the ulna below the origin of the abductor pollicis longus, and from the interosseous membrane. Originates from the posterior surface of the radius and interosseous membrane. In the hand, its tendon contributes to the lateral border of the anatomical snuffbox. Extensor pollisis brevis muscle origin, insertion,action. Extensor pollicis longus, extensor pollicis brevis, extensor indicis. C the extensor pollicis brevis tendon was repaired directly. Origin lower third of posterior shaft of radius and adjacent interosseous membrane.
The extensor pollicis brevis epb belongs to the deep group of the posterior fascial compartment of the forearm. Extends proximal phalanx of thumb at carpometacarpal joint innervation. The extensor pollicis longus or extensor pollicis longus muscle, latin. It has been shown that the intersection area where the apl and extensor pollicis brevis cross over the tendons of the extensor carpi radialis ecr. Origin and insertion extensor pollicis brevis originates from the posterior surface of the distal third of radius, inferior to the origin of extensor pollicis longus. Flexor pollicis brevis muscle an overview sciencedirect topics. Abductor pollicis brevis is the most lateral and the most superficial of thenar muscles, located underneath the skin. The extensor pollicis brevis originates from the lower third of the posterior surface of the.
Its tendon runs just lateral to the extensor pollicis longus tendon to insert at the base of the first phalanx of the thumb on the dorsal aspect. Posterior surfaces of radius and interosseous membrane. Insertion over tendons of radial extensors and brachioradialis to base of proximal phalanx of thumb. Posterior surfaces of radius and interosseous membrane insertion. Attaches to the base of the distal phalanx of the thumb. Check out the anatomy of the abductor pollicis brevis muscle, including its origin and insertion points, function and innveration. The present case reports about a variation in the origin of abductor pollicis. Pdf a rare origin of abductor pollicis longus researchgate. It lies on the medial side of, and is closely connected with, the abductor pollicis longus. If you have access to journal via a society or associations, read the instructions below.
The extensor pollicis brevis or extensor pollicis brevis muscle, latin. From here, the muscle runs downwards towards the wrist, ending in a cordlike tendon proximally to the wrist. Palmaris brevis muscle radiology reference article. Extensor pollicis brevis epb is one of the muscles of the deep layer of the posterior compartment of the forearm, inserting into the base of the proximal phalynx of the thumb. The extensor pollicis longus muscle begins at the ulna and the interosseous membrane, a tough fibrous tissue that connects the ulna and the radius in. Anatomy of forearm and wrist thumb musculoskeletal system. In human anatomy, the extensor pollicis longus muscle epl is a skeletal muscle located dorsally on the forearm. After the distal necrotic tendon was trimmed, the extensor pollicis longus tendon was sutured with the transferred extensor indicisproprius tendon by using 40 nonabsorbable sutures. It is much larger than the extensor pollicis brevis, the origin of which it partly covers and acts to stretch the thumb together with this muscle. The origin area extends to the adjacent interosseous membrane. Origin radius and the interosseous membrane insertion thumb.
The extensor pollicis brevis muscle is located on the dorsal side of the forearm. Posterior surface of the radius and the radioulnar interosseous membrane. The extensor pollicis brevis muscle has its origin on the dorsal surface of the radius below the abductor pollicis longus muscle. In a close relationship to the abductor pollicis longus, the extensor pollicis brevis both extends and abducts the thumb at the carpometacarpal and metacarpophalangeal joints. Posterior interosseous nerve c7 and c8, the continuation of the deep branch of the radial nerve arterial supply. The extensor hallucis brevis ehb is a muscle on the top of the foot that helps to extend the big toe. It also assists in extending and rotating the thumb. Dorsal ridge over dorsal base of proximal phalanx of thumb. Extensorpollicislongus or brevis tendon rupture after. Originates from the anterior surface of the radius, and surrounding interosseous membrane. Extensor pollicis brevis epb is one of the muscles of the deep layer of the posterior compartment of the forearm, insertion into the base of the proximal phalynx of. Insertion over tendons of radial extensors and brachioradialis to base. It originates from the trapezium and the flexor retinaculum. Injuries to wrist are common especially with the beginners due to direct impact over the wrist or due to offcenter handling.
The extensor pollicis longus originates from the posterior surface of the ulna and from the interosseous membrane of the forearm. This video explores the anatomy facts about the extensor pollicis brevis muscle, one of the deep forearm extensors. Extensor carpi radialis brevis extensor digitorum extensor digiti minimi. Release of the adductor pollicis, flexor pollicis brevis, or first dorsal interosseous muscle origins or insertions. Along with abductor pollicis longus it passes through the 1 st extensor compartment of the wrist. It runs from the scaphoid and trapezium bones, and from the flexor retinaculum to the proximal phalanx of thumb. The extensor pollicis brevis tendons are paired bands of connective tissue made of collagen that connect the extensor pollicis brevis muscles to bone. Extensor pollicis longus muscle, extensor pollicis brevis muscle. Extensor pollicis brevis lies radial to extensor pollicis longus. It is a part of the lateral border of the anatomical snuffbox. The extensor pollicis brevis is a skeletal muscle on the dorsal side of the forearm. The extensor pollicis longus extensor secundi internodii pollicis is much larger than the preceding muscle, the origin of which it partly covers.
The extensor pollicis brevis extensor primi internodii pollicis lies on the medial. Distal and dorsal aspect of radius, distal to the origin of abductor pollicis longus. The extensor pollicis brevis muscle can be found medially and deep to the abductor pollicis longus muscle. Extensor pollicis longus muscle wikimili, the free.
The extensor pollicis brevis originates from the lower third of the posterior surface of the radius and the interosseous membrane. It is essentially the medial part of the extensor digitorum brevis muscle. Extensor compartment muscles origin and insertion tendons go to the hand under the extensor retinaculum. The tendons of the extensor pollicis brevis and abductor pollicis longus form the radial border of the anatomic snuffbox. Abductor pollicis brevis, origin, insertion,action, exercise. Extensor pollicis brevis radiology reference article. Attachments of the extensor carpi radialis brevis muscle.
The palmaris brevis muscle, a small intrinsic muscle of the hand, is a quadrangularshaped subcutaneous muscle that overlies the hypothenar muscles, ulnar artery and superficial branch of the ulnar nerve at the medial side of the palm. Posterior interosseous artery the medical illustrations contained in this online atlas are. Flexor retinaculum and tubercles of scaphoid and trapezium insertion. The standard anatomical description of the extensor pollicis brevis epb found in current anatomical textbooks describes its origin as the posterior surface of the radius and the adjacent part of the interosseous membrane, distal to the attachment of the abductor pollicis longus apl. The extensor pollicis longus epl tendon resides within the 3 rd dorsal extensor compartment of the wrist, inserts upon the distal phalanx of the thumb, and is the primary extensor of the thumb. Extensor pollicis brevis belongs to the extensors of the forearm and participates in thumb extension.
The flexor pollicis brevis consists of two portions, superficial and and deep head. Insertion ulnar sesamoid then ulnar side of base of proximal phalanx and tendon of extensor pollicis longus. The abductor pollicis longus is a long, thin muscle of the forearm that not only allows you to give a thumbs up a motion called thumb extension but also allows. In a close relationship to the abductor pollicis longus, the extensor pollicis brevis both extends and abducts the thumb. Extensor carpi radialis brevis muscle getbodysmart.