What movement does the extensor digitorum muscle perform?
Christopher Anderson
Published Feb 14, 2026
What movement does the extensor digitorum muscle perform?
The extensor digitorum muscle (also known as extensor digitorum communis) is a muscle of the posterior forearm present in humans and other animals. It extends the medial four digits of the hand….
| Extensor digitorum muscle | |
|---|---|
| Nerve | posterior interosseous nerve |
| Actions | extension of hand, wrist and fingers |
What is the EDC in the hand?
The extensor digitorum communis is a superficial extensor muscle located in the posterior compartment of the forearm. It shares a common synovial tendon sheaths along with other extensor muscles which helps to reduce friction between the tendon and the surrounding structures.
What is the FDP tendon?
Flexor digitorum profundus (FDP) tendons FDP tendons help bend the index, middle, ring, and small fingers at the fingertip joint. The muscle that moves these tendons is a common muscle belly shared by all the fingers. The four tendons glide in sheaths along the hand and fingers and insert into the fingertip bone.
How do you test Fds for index finger?
In the present test, the subject is asked to press the finger tip pulp of all the fingers together against the proximal part of the palm (Fig. 1). If the FDS is acting, the DIP joint remains in a position of extension to hypertension while the metacarpo- phalangeal (MP) and PIP joints are fully flexed.
Where is the FDS tendon?
The FDS muscle forms 4 distinct bundles in the middle aspect of the forearm, each of which, in turn, forms 4 distinct tendons in the distal forearm. The tendons to the middle and ring fingers lie superficial to the tendons of the index and little fingers, a relationship that aids in their identification during surgery.
What are extensor muscles?
extensor muscle, any of the muscles that increase the angle between members of a limb, as by straightening the elbow or knee or bending the wrist or spine backward. The movement is usually directed backward, with the notable exception of the knee joint.
What is the function of the extensor digitorum longus?
The primary action of the extensor digitorum longus is to extend the lateral four toes at metatarsophalangeal joint. This means that when acting independently, it is unable to extend the entire length of the toes, extending only at metatarsophalangeal, while at the interphalangeal joints the toes remain flexed.
Is EIP ulnar to EDC?
Classically, a single slip of the extensor digitorum communis (EDC) and a single slip of the extensor indicis proprius (EIP) are said to run to the index finger. The EIP is said to be ulnar to the EDC at the level of the metacarpal head. Two hands had a double slip of the EDC running to the index.
Where does extensor digitorum insertion?
Lateral epicondyle of humerus
Extensor digitorum muscle
| Origin | Lateral epicondyle of humerus (common extensor tendon) |
|---|---|
| Insertion | Extensor expansions of digits 2-5 |
| Action | Metacarpophalangeal / Interphalangeal joints 2-5: Finger extension |
| Innervation | Posterior interosseous nerve (C7, C8) |
What are the Lumbrical muscles?
The lumbricals are deep muscles of the hand that flex the metacarpophalangeal joints and extend the interphalangeal joints. It has four, small, worm-like muscles on each hand. These muscles are unusual in that they do not attach to bone.
How many dorsal interossei are there in the human hand?
Structure. There are four dorsal interossei in each hand. They are specified as ‘dorsal’ to contrast them with the palmar interossei, which are located on the anterior side of the metacarpals. The dorsal interosseous muscles are bipennate, with each muscle arising by two heads from the adjacent sides of the metacarpal bones,…
What is the largest dorsal interossei muscle?
1st dorsal interosseous muscle: this muscle is the largest and strongest of the dorsal interossei and is sometimes referred to as abductor indicis. It arises from the adjacent surfaces of the 1st and 2nd metacarpal bones.
Where do you palpate the dorsal interossei?
Palpation. The dorsal interossei muscles can be palpated in the dorum of the hand on resisted abduction of the fingers between the metacarpals.
Where is the interossei muscle located on the hand?
On the first and second digit, the muscle lies on the lateral side and in the third and fourth digit, it lies off the medial side. The Dorsal Interossei muscles of the hand are all supplied by the deep branch of the ulnar nerve (C8, T1) . The Dorsal Interossei muscles of the hand are supplied by the dorsal and palmar interossei artery .
