Dr Pr. D’Agostino, MD, PhD

Hand Clinic Brussels - Lasne

LOUISE +32 2 534 29 99 LASNE +32 2 653 11 11

Mallet finger

QT Pathologies (EN)

A mallet finger is a deformity of the finger caused when the tendon that straightens your finger (extensor tendon) is damaged. The finger or thumb is not able to straighten.

  • Inability to straighten the finger Inability to straighten the finger

When a ball or other object strikes the tip of the finger or thumb and forcibly bends it, the force tears the tendon that straightens the finger (tendinous mallet finger). The force of the blow may even pull away a piece of bone along with the tendon (bony mallet finger).

Mallet finger can also occur by gradual wear and sometimes rupture of the extensor tendon on degenerative bone remodeling (see Osteoarthritis of the fingers section)

  • Mallet finger posttraumatic: clinical aspect (right) and radiographic (left) Mallet finger posttraumatic: clinical aspect (right) and radiographic (left)
  • Mallet finger on osteoarthritis Mallet finger on osteoarthritis
  • Pain and swelling over the end of the finger (especially if there is an associated fracture).
  • The end of the finger lies in a bent position.
  • Inability to hold the finger straight at the end joint.
  • Occasionally, blood collects beneath the nail.

The diagnosis is evident by the appearance of the finger. X-rays are often ordered to see if you have pulled off a piece of bone and to make sure the joint is aligned.


The majority of mallet finger injuries can be treated without surgery. Ice should be applied immediately, and the hand should be elevated (fingers toward the ceiling.) It is especially important to seek immediate attention if there is blood beneath the nail or if the nail is detached. This may be a sign of a nail bed lacération or an open (compound) fracture.

There are many different types of splints/casts for mallet fingers. The goal is to keep the fingertip straight until the tendon heals. Most of the time, a splint will be worn full time for eight weeks. Over the next three to four weeks, most patients gradually begin to wear the splint less frequently. The finger usually regains acceptable function and appearance with this treatment. Nevertheless, it is not unusual to lack some extension at the conclusion of treatment. Your surgeon will instruct you about how to wear the splint and will also show you exercises to maintain motion in the middle joint (proximal interphalangeal joint) so your finger does not become stiff. Once your surgeon feels your mallet finger has healed, she will show you exercises to regain motion in the fingertip itself.


Surgical repair may be considered when mallet finger injuries have large bone fragments or joint mal-alignment. In these cases, pins, wires or even small screws are used to secure the bone fragment and realign the joint.

Surgery may also be considered if non-surgical treatment is not successful in restoring adequate finger extension.

During your consultation, Dr. D'Agostino will discuss the current treatment options and can help you choose the best treatment based on your particular case.

  • Examples of bone mallet finger synthesis Examples of bone mallet finger synthesis