Extensor tendon compartments of the wrist

Extensor Tendon Compartments of the Wrist

The wrist is a complex joint that is made up of multiple bones and soft tissues. One of the key components of the wrist are the extensor tendon compartments. These compartments house the extensor tendons, which are crucial for wrist and hand movement.

Anatomy

There are six extensor compartments in the wrist, each containing one or more extensor tendons. These compartments are numbered from the radial (thumb) side to the ulnar (little finger) side of the wrist.

1. First Compartment: Contains the Abductor Pollicis Longus and Extensor Pollicis Brevis. These tendons help in thumb abduction and extension respectively.
2. Second Compartment: Houses the Extensor Carpi Radialis Longus and Extensor Carpi Radialis Brevis. These tendons are responsible for wrist extension and radial deviation.
3. Third Compartment: Contains the Extensor Pollicis Longus, which extends the thumb.
4. Fourth Compartment: Contains the Extensor Digitorum and Extensor Indicis. These tendons extend the fingers.
5. Fifth Compartment: Contains the Extensor Digiti Minimi, which extends the little finger.
6. Sixth Compartment: Contains the Extensor Carpi Ulnaris, which extends and adducts the wrist.

Each compartment is lined with a synovial sheath that reduces friction as the tendons move.

Clinical Significance

Inflammation of the synovial sheaths can lead to a condition known as De Quervain's Tenosynovitis, which affects the first extensor compartment. This condition is characterized by pain and swelling on the thumb side of the wrist.

Extensor Tendonitis is another common condition that can affect any of the extensor compartments, leading to pain, swelling, and difficulty in moving the wrist or fingers.

Treatment

Treatment for conditions affecting the extensor compartments typically involves rest, immobilization, and anti-inflammatory medications. In severe cases, surgery may be required to release the affected compartment and relieve pressure on the tendons.