Extensor digiti minimi muscle

From WikiMD's Wellness Encyclopedia

Extensor digiti minimi is a muscle in the forearm of humans that extends the little finger. It is also known as extensor digiti quinti proprius, a name that distinguishes it from the extensor digiti quarti proprius, a former name for the extensor indicis.

Etymology[edit | edit source]

The term "extensor digiti minimi" comes from Latin, with "extensor" referring to any muscle that extends or straightens a limb or body part, "digiti" meaning "of the finger", and "minimi" meaning "smallest". Thus, the term can be translated as "extensor of the smallest finger".

Structure[edit | edit source]

The extensor digiti minimi is located on the ulnar side of the forearm and is quite distinct from the other extensor muscles in this region. It originates from the common extensor tendon, which arises from the lateral epicondyle of the humerus, and from the intermuscular septa between it and the adjacent muscles. The muscle's tendon runs through the fourth compartment of the dorsal carpal tunnel and inserts into the extensor expansion of the little finger.

Function[edit | edit source]

The primary function of the extensor digiti minimi is to extend the little finger. It also assists with wrist extension. This muscle is used during many everyday activities, including typing, writing, and gripping objects.

Clinical significance[edit | edit source]

Injury to the extensor digiti minimi can result in a loss of ability to extend the little finger, a condition known as "mallet finger". This can occur as a result of direct trauma, such as a blow to the back of the hand, or from overuse, such as from prolonged typing or playing a musical instrument.

Related terms[edit | edit source]

  • Extensor muscles: A group of muscles that help to extend or straighten out joints.
  • Forearm: The part of the arm between the elbow and the wrist.
  • Humerus: The bone of the upper part of the arm or forelimb, extending from the shoulder to the elbow.
  • Carpal tunnel: A narrow passageway in the wrist, through which pass the tendons of the flexor muscles and the median nerve.
Extensor digiti minimi muscle Resources

Contributors: Prab R. Tumpati, MD