Extensor digitorum

Extensor Digitorum Muscle

Extensor Digitorum

You have Extensor Digitorum muscle both in your forearm and leg. As the name implies, it is a key muscle for performing extension.

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Extensor Digitorum of forearm

The extensor digitorum or extensor digitorum communis ( Latin name: musculus extensor digitorum) is a long, superficial muscle present in the backside of the forearm. It is the most superficial muscle in the posterior muscle group

Origin and Insertion

Extensor digitorum of forearm and hand
Extensor digitorum of forearm and hand

Origin: Lateral epicondyle of the humerus.

Insertion: Distal phalanges of 2nd, 3rd, 4th, and 5th fingers.

Extensor Digitorum muscle takes its origin from the lateral epicondyle of humerus in the backside of the forearm and the gets subdivided into four tendons in the hand and gets inserted into the medial four fingers. The tendons to the four digits are interconnected with two slanting bands. The 1st and 2nd tendons may be interconnected by a small transverse band. These bands are called the sagittal bands. These bands keep the extensor tendons aligned well above the metacarpal head. This aids to improve the hand’s leverage.

Ref: https://en.wikipedia.org/wiki/Extensor_digitorum_muscle


Action on the wrist

Extensor digitorum muscle helps to extend the wrist (or hand) and then the elbow.

Action on the fingers

Extensor digitorum muscle helps to extend the medial 4 fingers (2nd-5th digit), especially the extension of the middle phalanx of these digits.

Advanced functions

The extensor digitorum acts on the proximal phalanges to extend the metacarpophalangeal joint. As it extends the fingers, it tends to keep them separated. However, the dorsal and palmar interossei and lumbrical muscles of the hand mediates the extension of the proximal and distal phalanges.

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Nerve supply

The posterior interosseous nerve (C7, C8) supplies the Extensor digitorum muscle, branch of the radial nerve.

Blood supply

The arterial supply is the posterior interosseous artery, a division of the Ulnar Artery.

Pain in extensor digitorum

Physical therapy
Pain in extensor digitorum

If you are musician or a typist and work for hours using your finger your extensor digitorum communis muscle may tighten, Because of this you may develop pain in your elbow and forearm. You may develop tightened muscle and trigger points due to excessive repetitive finger movements. Damage to the nerve which supplies this muscle may even cause some clinical conditions.

The following are the activities which may cause problems in your extensor digitorum muscle

  • Playing Piano, guitar, keyboard, flute, saxophone, violin
  • Rockclimbing
  • Gardening
  • Creating sculptures
  • Typing on the computer for a long time

Self-releasing of trigger points

The trigger points in this muscle send pain through the elbow, forearm, back of the hand, at the base of your thumb near the wrist and 3rd and 4th digits. You will experience severe pain in your finger joints due to overwork.

For releasing the trigger points by massaging you can either use hands or massage balls. Press against the walls placing a massaging ball on the extensor digitorum muscle. Roll over the ball on the tender and painful spots. repeat it for 15 to 20 times very slowly with gentle strokes. If you are using your hands find the trigger tender point and massage slowly with deep strokes. Repeat it for 15 to 20 times. Don’t need to massage the entire muscle it is enough to massage only on the painful spots.

Tennis elbow

Tennis elbow or lateral epicondylitis in this condition the muscle tendons which join your forearm with the elbow gets inflamed due to repetitive movements of the some. In some cases, tennis elbow is seen in people who work repeatedly with their fingers
This leads to tenderness and severe pain. The pain develops outside your elbow, in your forearm and wrist. The doctors may prescribe you some pain killers, non-steroidal anti-inflammatory drugs. And you must take rest and take necessary self-care. Physical therapy sessions might also work very well.

Impaired movements

In overworked and a tender muscle which is nearly wasted, one might face gripping problems, you may not able to put a hold on thing to move things like holding a cup, shaking hands. In severe conditions you will have severe pain even when moving your fingers you will have a very weak grip.

How to prevent these problems

There is an effective way to reduce or prevent these complications. This includes self-massage. You might have hours of work to do, but u have to spend at least 5 to 10 minutes each one hour so that you can avoid expensive hospital bills.

Extensor digitorum muscles of the leg and feet

The extensor digitorum longus and extensor digitorum brevis are present in the anterior part of the leg and dorsal aspect of the foot (upper surface of the foot).

Extensor digitorum longus

This muscle, extensor digitorum longus is present on the lateral side of the front of the leg. It extends from below the knee joint, across the ankle joint and goes up to the toes. The extensor digitorum is the walking muscle and performs several important movements of the ankle and foot.

Origin and Insertion

Origin: Extensor digitorum takes its origin from many places, lateral condyle of the tibia, the front surface of the fibula, and the upper part of interosseous membrane (fibrous sheath that is present in between the two leg bones, Tibia and Fibula).

Insertion: The muscle passes under both the extensor retinaculum and gets inserted into the middle and distal phalanges of the second to the fifth digit

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It helps in the extension of the toes and dorsiflexion of the ankle joint.

Nerve supply

The deep fibular nerve supplies the extensor digitorum longus.

Blood supply

Anterior tibial artery supplies the extensor digitorum longus muscle

Trigger points and Extensor tendonitis

Extensor digitorum longus
Extensor digitorum longus

The extensor tendons likely vulnerable to injury. These tendons become tightened or inflamed due to overuse. It may cause a severe and painful condition called the Extensor tendonitis. Some times pain triggers in some areas of the muscle due to repeated use. The common trigger point occurs at the lower third of the lateral side of your legs To release the trigger points you may look for the tender points and massage it with a massaging ball or fingertips as I mentioned the techniques of massaging above. This is surely an effective way to release the pain. In some severe conditions, it may be due to muscle wasting or inflammation.

Extensor tendonitis

In this condition, the tendons of the extensor muscles of your feet get inflammation. It mostly occurs when you stand on your leg for several hours or wear a very tight shoe.

Causes and Impaired movements

Due to the inflammation, your tendons become very weak. You will feel pain on the upper surface of your foot most of the time at the midpoint. The pain continues and increases gradually as you keep on using the damaged muscle. It decreases the ability to move your toes and makes activities like jumping, dancing, or running difficult. When you stand or walk with a force pain keeps aggravating in the areas. Extensor tendons get irritated when overuse. Running uphill for over a long distance may also trigger inflammation. Don’t wear shoes that are too tight. Don’t lace up the shoes so hard compressing the extensor tendons.

If your pain is on top of your foot only for a few days it might be a mild inflammation, self-care and self-massaging are enough. If the pain increases day by day and remains for many days consult a doctor immediately. Go to a podiatrist or an orthopedist, he will diagnose with x-rays MRI, ultrasound and find the cause of the injury or pain.


The treatment may vary regarding the seriousness of the injury. If the injury or damage to the tendon is very severe You may require surgery, It takes usually several weeks to heal. After surgery, physical therapy is a must.

In mild cases, surgery is not required. You have to rest so that the healing occurs fast. Don’t give any work to the tendon or muscle. Ice the area to reduce the inflammation. You can take pain relievers such as nonsteroidal anti-inflammatory drugs (NSAIDs) to relieve the pain. Perform stretching exercises to regain the strength and flexibility of the tendon.

Go for physical therapy (PT), it may get your tendons back to position and strengthen it by strengthening and stretching exercises such as calf stretches which are good for the feet. Steroid injections are used in very serious conditions.

Extensor digitorum brevis

The extensor digitorum brevis (Latin: musculus extensor digitorum brevis) is present in the dorsal surface of the foot and helps in the extension of the toes.

Origin and Insertion

Extensor digitorum brevis
Extensor digitorum brevis

Origin: It takes its origin from the upper superior and lateral part of the calcaneus bone.

Insertion: This muscle passes forward on the dorsal aspect of the foot and gets inserted into the tendon of extensor digitorum longus.


This muscle acts on the extension of the 2nd, 3rd, 4th digit.

Advanced functions

Additionally, extensor digitorum brevis provides an extension of the first four digits at the metatarsophalangeal joint, At the same time, it extends the 2nd to 4th digit at the interphalangeal joint.

Nerve supply

The nerve supply is the same as the extensor digitorum longus it is supplied by the deep fibular nerve

Blood supply

The arterial supply is a branch of the anterior tibial artery, the dorsalis pedis artery

The pain or inflammation in this muscle is as same as the extensor tendons, I have mentioned above.

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I hope you find this article use full. It is always good to consult the doctor in the first cases itself. Don’t wait so long and get bedridden for months, Treat at the first possible time itself. If you are a working person and even you work for hours. Remember to pause your work for a few minutes thinking about your family relax and do some stretching exercises and then resume back to work.