Mallet Finger

Mallet finger, a condition that causes in pain, swelling, bruising and an inability to straighten the digit, can result when the extensor tendon of the finger is forcibly stretched or torn.


In some cases, the tendon ruptures or pulls away from where it attaches to the bone. When this happens, an avulsion fracture can also occur, in which a small piece of bone is pulled off along with the tendon.

This condition more often affects the middle, ring and little fingers of the dominant hand.

Causes of Mallet Finger

Tendons connect muscles to bone. The extensor tendons are located at the top of the hand, and they connect to the muscles that straighten the fingers. Injuries to these tendons most commonly occur as a result of an object striking the tip of the finger. The force of the blow bends the finger or thumb further than it is intended to go.

Sports injuries, particularly from catching a ball, are responsible for most cases of mallet finger. For this reason, the condition is also referred to as baseball finger.

But this type of injury isn’t always sports-related. Any rapid motion that jams the finger against an unyielding object — such as the action of tucking in a bedsheet — can cause damage to the extensor tendons. In some cases, the injury occurs as a result of a knife accident in the kitchen or a crushing accident on the job.

Mallet Finger Diagnosis

To diagnose this condition, the orthopedic surgeon will begin by taking a medical history and performing a physical examination.

Mallet finger is typically easy to diagnose, as the tip of the affected digit droops and the patient is unable to extend it. To determine if an avulsion fracture is present and if the bones of the joint are out of alignment, the surgeon will typically order X-rays.

Patients with this type of injury often delay seeking medical attention because they can still use their hand. However, prompt treatment is necessary to regain function in the finger.

It is essential to seek immediate medical care if the fingernail has become detached or if blood can be seen under the nail. These are common signs that the bone is broken or that there is an open fracture, and these injuries can put you at greater risk for infection.

Treatments for Mallet Finger

Most cases are treated with splinting. A splint to hold the tip of the finger in a straight, extended position must be worn until the injury has healed.

Patients are advised to keep the splint on at all times, even while bathing. If the splint gets wet, it can be changed for a new one, but the digit must be kept straight, or the healing process will be disrupted and you may have to wear the splint longer.

In some cases, however, surgical treatment is needed. If a large fracture fragment is present, or if the joint is out of line, orthopedic surgery may be the only way to successfully treat mallet finger.