Brief Outline of Mallet Finger
Extensor tendons are vulnerable to injury, lying just below the skin surface directly on the bones of the back of the hand and fingers. Such tendons may be torn apart when a finger is jammed, separating the tendons from their attachment to bone. The injury is common at the start of baseball season, often caused by a ball hitting the fingertip, bending it sharply downard and tearing the extensor tendon. Cuts to the hand or fingers can also damage the extensor tendons.
Anatomy and physiology
Extensor tendons are small muscle tendons in the hand and fingers, which provide for delicate movements and hand coordination. They are located on the dorsal aspect of the hand and fingers, allowing the athlete to extend and straighten the fingers and thumb. Extensor tendons attach to muscles in the forearm. When an object hits the fingertip, the forceful flexion of the distal phalanx avulses the lateral bands of the extensor mechanism from its distal attachment.
Cause of Mallet Finger Injury
Cuts or lacerations affecting the extensor tendons. Baseball, volleyball, football, basketball or other object striking the fingertips while the extensor tendon is taut. Jamming the finger against a wall, door or other immovable object.
Signs and symptoms of Mallet Finger Injury
Inability to extend the finger. Bruising, pain, and swelling of the affected finger. Drooping fingertip.
Complications if left unattended
Left untreated, mallet finger may cause permanent cosmetic deformity in the finger, though often without further complication. Without splinting however, some residual stiffness and loss of finger extension may result.
Immobilisation with a splint is a conservative method to treat mallet finger. However, for easier and more comfortable method, surgical intervention is advised.
Rehabilitation and prevention
Generally, a splint must be worn continuously until the extensor tendon is fully healed. It will often require several months for local swelling and erythema to fully subside. Special care to the fingertips should always be taken in sports involving fat-moving balls, as well as when handling cutting implements.
With attention to post-injury care including immobilisation of the injured finger, most athletes achieve full restoration of movement and appearance of the digit.