Collateral ligament of thumb

Collateral ligament of thumb is a crucial component of the human hand anatomy. It is responsible for the stability and mobility of the thumb, one of the most frequently used parts of the hand.

Anatomy

The collateral ligament of the thumb, also known as the ulnar collateral ligament, is located on the medial side of the metacarpophalangeal joint (MCP joint) of the thumb. It is composed of two parts: the proper collateral ligament and the accessory collateral ligament.

The proper collateral ligament is a strong, rounded cord that extends from the posterior tubercle of the metacarpal bone to the base of the proximal phalanx. The accessory collateral ligament, on the other hand, is a flat, quadrilateral band that extends from the volar plate to the base of the proximal phalanx.

Function

The primary function of the collateral ligament of the thumb is to provide stability to the thumb, particularly during pinching and gripping movements. It prevents excessive lateral movement of the thumb, thus protecting the MCP joint from potential injuries.

Injuries

Injuries to the collateral ligament of the thumb, commonly known as skier's thumb, are relatively common. They typically occur due to a sudden force that causes the thumb to bend away from the hand, such as during a fall or when the thumb is caught in a ski pole strap.

Treatment for collateral ligament injuries depends on the severity of the injury. Mild injuries can often be treated with rest, ice, compression, and elevation (RICE), while severe injuries may require surgical intervention.

See also

• Metacarpophalangeal joint
• Phalanx bone
• Skier's thumb