Name

# Flexor Digitorum Superficialis

Pronunciation

(FLEK-sur dij-i-TOR-um soo-pe-fish-e-A-l us)

Origin/Proximal Attachment

Humeral-Ulnar Head: medial epicondyle of the humerus via the common flexor tendon; medial border of base of coronoid process of ulna; medial collateral ligament; antebrachial fascia

Radial Head: oblique line of radius along its anterior surface

Insertion/Distal Attachment

Both sides of the base of each middle phalanx of the 4 fingers

Action/Relevance

Flexes the proximal & middle phalanges

Flexes the wrist if fingers are extended

Innervation

Median nerve (C7, 8,T1)

Notes

Flexor digitorum superficialis is an extrinsic flexor muscle of the fingers. The bulk of the muscle is in the anterior of the forearm.

Like most flexors of the arm, it is supplied by the median nerve. Its blood comes from the ulnar artery. The proximal attachment includes the median epicondyle of the humerus as well as parts of the radius and ulna.

Four long tendons come off this muscle, and travel through the carpal tunnel. They then attach to the base of the proximal phlanges on the four fingers. These tendons have a split, or a hole, at the end of them through which the tendons of flexor digitorum profundus will travel.