A mallet finger injury is a tear of the tendon that straightens the end joint of the finger. This injury is often caused by a ball hitting the tip of the finger but can also result from a minor injury such as catching the finger when tucking in bed sheets. The tendon may tear where it joins on to the end bone of the finger – or it may pull off a small fragment of bone at this point (in which case it is called a mallet fracture). Occasionally the injury is “open ‟, where tendon is divided by a cut through the skin.
What are the symptoms?
- Pain and swelling over the end of the finger.
- The end of the finger sits in a bent position.
- Inability to hold the finger straight at the end joint.
An x-ray should be taken to look for a fracture.
A splint will be applied to keep the finger in a straight position at the end joint (see photo above). Hand Therapists will often custom make splints to ensure good fit and that the splint does not allow any movement of the end joint whilst healing. The splint will have to be worn continuously for six to eight weeks. You may be shown how to change the splint safely. At the end of this time the splint is often worn for a further one to two weeks at night and whenever the finger might be at risk of injury.
Severe mallet fractures sometimes require surgical treatment.
Most closed injuries treated early with a splint alone will heal satisfactorily leaving normal function in the affected finger. There may be slight loss of full straightening at the completion of treatment, and it may take several months to regain satisfactory function. Redness, swelling and tenderness of the skin on top of the end joint are common for three or four months after injury, but usually settle.
Mallet fractures may leave a small bump on the top of the end joint and slight loss of bending of the joint, but pain is rare and the finger generally functions well.