Mallet finger

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What is mallet finger?

Mallet finger is an injury to the extensor tendon that straightens the joint at the end of the finger. The injury is also called “baseball finger” because it occurs in sports such as baseball and basketball. Typically, the ball hits the tip of the finger and jams it, causing the tendon to detach from the bone. The finger then bends or droops at the last joint and cannot be straightened.

What causes mallet finger?

Mallet finger most commonly results from direct trauma, often during sports when a ball strikes the extended finger. Another cause is laceration to the back of the finger. In some cases, the tendon is pulled away from the bone, breaking a piece of bone from the attachment point. This type of injury is called a bony mallet finger.

What are the symptoms?

The main symptoms of mallet finger are a downward turn in the tip of the finger and an inability to straighten the finger. Other symptoms may include pain, swelling and tenderness, especially when bony mallet finger is involved.

How is mallet finger diagnosed?

In addition to a complete physical exam and patient history, your doctor may order an X-ray to confirm the diagnosis and rule out other damage to your finger or hand. You should see your doctor if there is any deformity or decreased movement in your finger, or if pain persists more than a day or two.

What is the treatment?

In the vast majority of cases, mallet finger is treated with a splint for eight to twelve weeks. However, if the bone fragment is very large or the joint is displaced, surgery may be recommended. Surgical options include fixation, in which the tendon is fixed in place with a pin to stabilize the joint as it heals; fracture repair, in which pins are used to hold pieces of bone together as the injury heals; or fusion to bind the joint surfaces of the finger together. It’s important that you consult a qualified orthopedic surgeon who can evaluate your case and recommend the best course of action.