- Flexor digitorum superficialis muscle
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Flexor digitorum superficialis 
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 medial epicondyle of the humerus (common flexor tendon) as well as parts of the radius and ulna. Insertion anterior margins on the bases of the middle phalanges of the four fingers Artery ulnar artery Nerve median nerve Actions flexor of fingers (primarily at proximal interphalangeal joints) Antagonist Extensor digitorum muscle 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 part of the superficial layer of this compartment,[1][2] and sometimes considered to be a distinct, "intermediate layer" of this compartment.[3] It is relatively common for the Flexor digitorum superficialis to be missing from the little finger, bilaterally and unilaterally, which can cause problems when diagnosing a little finger injury. [4]
Contents
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. The ulnar collateral ligament of elbow joint gives its origin to part of this muscle.
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 middle 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.
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 inactivate flexor digitorum profundus).
Additional images
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Bones of left forearm. Anterior aspect.
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Bones of the left hand. Volar surface.
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Tendons of forefinger and vincula tendina.
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Cross-section through the middle of the forearm.
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Transverse section across the wrist and digits.
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The mucous sheaths of the tendons on the front of the wrist and digits.
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The muscles of the thumb.
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The muscles of the left hand. Palmar surface.
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The radial and ulnar arteries.
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Flexor digitorum superficialis muscle
References
- ^ Mnemonic at medicalmnemonics.com 273 1117
- ^ "Dissector Answers - Forearm & Wrist". http://anatomy.med.umich.edu/musculoskeletal_system/forearm_ans.html#2o. Retrieved 2008-01-17.
- ^ "uams.edu". http://anatomy.uams.edu/AnatomyHTML/topogr_upperlimb.html. Retrieved 2008-01-17.
- ^ "J Hand Surg Eur". http://jhs.sagepub.com/content/35/5/417.abstract. Retrieved 2011-02-06.
External links
List of muscles of upper limbs (TA A04.6, GA 4.432) Shoulder deltoid · rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) · teres major
fascia: Deltoid fascia · Supraspinous fascia · Infraspinous fasciaArm
(compartments)OtherForearm superficial: pronator teres · palmaris longus · flexor carpi radialis · flexor carpi ulnaris · flexor digitorum superficialis
deep: pronator quadratus · flexor digitorum profundus · flexor pollicis longusOtherHand Lateral volarMedial volarhypothenar (opponens digiti minimi, flexor digiti minimi brevis, abductor digiti minimi) · palmaris brevisIntermediateposterior: Extensor retinaculum · Extensor expansion
anterior: Flexor retinaculum · Palmar aponeurosisCategories:- Muscles of the upper limb
- Forearm
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