Extensor tendons

Structures that connect muscles to bones, facilitating movement in the fingers and toes.

Extensor tendons are fibrous tissues that attach the extensor muscles of the forearm and lower leg to the bones of the fingers, hands, toes, and feet. These tendons are essential for the extension movement, allowing fingers and toes to straighten or spread apart. They transmit the force generated by the muscles to the skeletal system, enabling precise movements necessary for daily activities.

Terminologia Anatomica

tendo-extensor

System

Muscular system

Function

The primary function of extensor tendons is to facilitate the extension of various digits. This action is critical for grip and manipulation, allowing the hand to open and hold objects effectively. In the toes, the extension provided by these tendons is pivotal for walking, running, and maintaining balance. Without functioning extensor tendons, basic actions like typing or playing instruments would be severely compromised. These tendons work in coordination with the flexor tendons, which perform the opposing function of bending the fingers and toes, hence promoting smooth and controlled movements. Their role in fine motor skills is particularly important, making them integral to numerous tasks performed throughout the day.

Location

Extensor tendons originate from extensor muscles in the forearm and the lower leg, extending towards the digits. In the hands, the extensor tendons travel along the back of the wrist and hand, entering the digits at the metacarpophalangeal joints. They pass through various compartments, including the dorsal carpal ligament, and run toward the fingers, where they attach to the proximal, middle, and distal phalanges. In the feet, extensor tendons similarly travel from their originating muscles in the anterior compartment of the leg, crossing over the ankle, and extending into the toes through the dorsal aspect of the foot. This positioning allows for effective and powerful extension of the digits during movement.

Did You Know?

The extensor tendons in the fingers can be seen from the back of the hand as they create visible lines when the fingers are extended.
Injuries to the extensor tendons can lead to conditions like 'mallet finger', where a person cannot extend the tip of a finger.
The extensor tendons of the toes are essential for controlling foot placement and balance during activities like walking or running.