Finger, bent fingertip

'Mallet finger' is an injury to the end of the finger that causes it to bend towards the palm.

You won't be able to straighten the end of the finger because the tendon that connects the muscle to the finger bone is torn. The finger will also be painful and swollen.

Mallet finger is most often caused by a trivial injury, such as catching the finger while tucking in bed sheets, or catching it on a coat.

What should I do?

If you think you have mallet finger, go to your nearest minor injuries unit or accident and emergency (A&E) department to have it splinted. You should do this as soon as possible – the earlier it is treated, the better the outcome.

Try to keep your hand raised until the doctor sees you – this will help to reduce any swelling and pain.

You can take an over-the-counter painkiller, such as paracetamol, to relieve the pain.

How is it treated?

Your finger will be placed in a plastic splint, which keeps it straight with the end joint slightly bent backwards. You'll still be able to bend the finger at the middle joint.

The splint is taped on and must be worn day and night for six to eight weeks to allow the two ends of the torn tendon to stay together and heal. It should only be removed for cleaning (see below).

It's really important that the end of your finger does not bend during the time it is splinted, as this may slow down healing.

You should only need surgery if the finger bone has broken (known as a mallet fracture), or in the uncommon situation where the mallet finger fails to heal.

How do I keep my finger and splint clean?

The splinted finger must be kept clean and dry at all times. If the skin becomes wet inside the splint, it will become very sore.

It's important to wash both your finger and the splint at least once a day, following these instructions:

• Keep your finger flat on the table, cut the strapping, and slide the splint off your finger.
• Wash and dry your finger and the splint using soap and water. Keep the end joint straight at all times by keeping your finger flat on the table. You may find it easier if someone helps you to do this each day, as any movement of the end of the finger will delay healing of the tendon and may even cause permanent damage.
• Slide the splint back over the fingertip, still keeping the finger straight.
• Replace the strapping – this should cover the middle of the splint but should not cover the middle joint of the finger.

How long will it take to heal?

Your mallet finger should heal within six to eight weeks, after which time you'll be able to use the finger again. You may be advised to continue to wear the splint at night for a few more weeks.

It may take several months to regain full function.

Redness, swelling and tenderness of the skin around the end of the finger are common for three or four months after injury, but usually settle eventually.

You may be left with a small bump on the top of the joint and a slight loss of ability to straighten the joint (it never really goes completely back to normal). However, the finger should generally function well.