Extensor tendon compartments of the wrist

Extensor Tendon Compartments of the Wrist

Diagram of the extensor tendon compartments of the wrist, numbered.

The extensor tendon compartments of the wrist are anatomical structures that house the tendons responsible for the extension of the wrist and fingers. These compartments are located on the dorsal side of the wrist and are crucial for the coordinated movement of the hand and fingers. Each compartment contains specific tendons that pass under the extensor retinaculum, a fibrous band that holds the tendons in place.

Anatomy

The extensor tendon compartments are numbered from lateral (thumb side) to medial (little finger side) and are as follows:

First Compartment

The first compartment contains the tendons of the abductor pollicis longus and the extensor pollicis brevis. These tendons are responsible for the abduction and extension of the thumb.

Second Compartment

The second compartment houses the tendons of the extensor carpi radialis longus and the extensor carpi radialis brevis. These tendons extend and abduct the wrist.

Third Compartment

The third compartment contains the tendon of the extensor pollicis longus, which extends the thumb.

Fourth Compartment

The fourth compartment is the largest and contains the tendons of the extensor digitorum and the extensor indicis. These tendons extend the fingers and the index finger, respectively.

Fifth Compartment

The fifth compartment contains the tendon of the extensor digiti minimi, which extends the little finger.

Sixth Compartment

The sixth compartment houses the tendon of the extensor carpi ulnaris, which extends and adducts the wrist.

Function

The primary function of the extensor tendon compartments is to facilitate the extension of the wrist and fingers. This is essential for various hand movements, including gripping, releasing, and fine motor skills. The compartments also help in stabilizing the tendons and preventing bowstringing during wrist and finger movements.

Clinical Significance

Anatomical illustration of the wrist showing the extensor tendons.

The extensor tendon compartments are clinically significant due to their involvement in various conditions:

• De Quervain's Tenosynovitis: This condition affects the first compartment and is characterized by pain and swelling near the base of the thumb.
• Intersection Syndrome: This occurs when the tendons in the first and second compartments intersect, leading to pain and swelling.
• Extensor Tendonitis: Inflammation of the tendons within any of the compartments can lead to pain and impaired function.

Related Pages

• Extensor retinaculum of the hand
• Flexor retinaculum of the hand
• Wrist joint
• Tendon