Flexor digitorum superficialis muscle
From Wikipedia, the free encyclopedia
| Flexor digitorum superficialis | ||
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| Transverse section across distal ends of radius and ulna. (Flexor dig. subliminis labeled at center top.) | ||
| Latin | musculus flexor digitorum superficialis | |
| Gray's | subject #125 448 | |
| Origin: | median epicondyle of the humerus (common flexor tendon) as well as parts of the radius and ulna. | |
| Insertion: | phalanges | |
| Artery: | ulnar artery | |
| Nerve: | median nerve | |
| Action: | flexor of fingers (primarily at proximal interphalangeal joints) | |
| Antagonist: | Extensor digitorum muscle | |
| Dorlands/Elsevier | m_22/12549098 | |
Flexor digitorum superficialis (flexor digitorum sublimis) is an extrinsic flexor muscle of the fingers at the proximal interphalangeal joints. The bulk of the muscle is in the intermediate layer of the anterior compartment of the forearm.
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[edit] Origin and Insertion
The muscle has two classically described heads - the humeroulnar and radial - and it is between these heads that the median nerve and ulnar artery pass.
Four long tendons come off this muscle near the wrist and travel through the carpal tunnel formed by the flexor retinaculum. These tendons, along with those of flexor digitorum profundus, are enclosed by a common flexor sheath. The tendons attach to the anterior margins on the bases of the proximal phalanges of the four fingers. These tendons have a split (Camper's Chiasm) at the end of them through which the tendons of flexor digitorum profundus pass.
[edit] Function
The primary function of flexor digitorum superficialis is flexion of the middle phalanges of the fingers at the proximal interphalangeal joints, however under continued action it also flexes the metacarpophalangeal joints and wrist joint.
To test flexor digitorum superficialis, one finger is flexed at the proximal interphalangeal joint against resistance, while the remaining three fingers are held fully extended (to inactive flexor digitorum profundus).
[edit] Additional images
 Bones of left forearm. Anterior aspect. |
 Bones of the left hand. Volar surface. |
 Tendons of forefinger and vincula tendina. |
 Cross-section through the middle of the forearm. |
 Transverse section across the wrist and digits. |
 The mucous sheaths of the tendons on the front of the wrist and digits. |
 The muscles of the thumb. |
 The muscles of the left hand. Palmar surface. |
 The radial and ulnar arteries. |
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