A mallet finger injury occurs after a blunt injury to a fingertip. This injury affects the thin tendon that is responsible for straightening the end joint of a finger or thumb, called the extensor tendon. Mallet finger, also known as baseball finger, is a common injury which typically occurs when someone knocks their finger when trying to grab something. This results in sudden flexion of the fingertip and causes the extensor tendon to pull off. The tendon either pulls directly off the bone, or a piece of bone breaks off with it. When a piece of bone breaks off as well, it is called a mallet fracture.
The appearance of a mallet finger is one where the joint nearest the tip of the finger stays in a bent position, and it is not possible to straighten it. The most common symptom of a mallet finger is when the finger becomes painful right after the injury, and the fingertip then droops. In some cases, the pain may be associated with a bone fracture. Other symptoms may include redness, swelling, bruising, tenderness and the inability to straighten the fingertip. If the nail is also injured and has detached from the nail bed, or has blood underneath it, it may be a result of a cut or a bone fracture. It is essential that you visit the doctor for immediate medical attention, as there may be a risk of developing an infection.
Most of these can be treated conservatively in a splint which should be worn full time for 6-8 weeks. Occasionally if a large piece of bone has pulled off, or if it slips out of joint, then surgery may be required. Surgery may also be indicated if conservative treatment is not successful in restoring adequate finger extension. It may include the use of pins, wires and small screws to secure the bone fragments and also realign the joint.