tommelligamentet

Tommelligamentet, also known as the collateral ligament of the thumb or the ulnar collateral ligament of the thumb, is a crucial ligament in the hand. It is located on the ulnar side of the thumb, connecting the proximal phalanx of the thumb to the first metacarpal bone. Its primary function is to provide stability to the metacarpophalangeal (MCP) joint of the thumb. This joint is the primary hinge joint of the thumb, allowing for flexion and extension.

The tommligamentet is composed of two distinct bands: a proper volar ligament and a distal accessory ligament. The proper volar ligament originates from the head of the first metacarpal bone and inserts onto the base of the proximal phalanx. The accessory ligament originates from the palmar aspect of the metacarpal head and inserts onto the volar plate, a fibrocartilaginous structure that reinforces the palmar aspect of the MCP joint.

Injury to the tommligamentet is common and often occurs due to forceful abduction or hyperextension of the thumb. This can happen during sports activities, falls, or direct trauma. A common presentation of this injury is known as "skier's thumb" or "gamekeeper's thumb," which typically involves a tear of the ulnar collateral ligament. Symptoms can include pain, swelling, bruising, and instability of the thumb, making gripping and pinching movements difficult. Diagnosis is usually made through clinical examination, and imaging such as X-rays or MRI may be used to assess the severity of the injury. Treatment options range from conservative management, such as splinting and rest, to surgical repair or reconstruction, depending on the degree of ligamentous damage.