Other common names
Extensor tendon rupture
Who does it affect?
Why does it happen?
When a finger is forcibly stubbed, the end finger joint (distal interphalangeal joint) bends forwards quite suddenly. This causes the tendon on the back of the finger that straightens the end joint to pull off the bone. Usually it pulls off without a piece of bone but sometimes it can pull of a fragment.
Sudden inability to fully straighten the end finger joint and the joint is held in a bent position.
You will be asked to try and straighten your end finger joint. You will not be able to do this, no matter how hard you try.
An x-ray is required to see whether the tendon has pulled off a piece of bone. This will dictate treatment.
The vast majority of mallet finger injuries do not need an operation. If an x-ray reveals the tendon has pulled off a large fragment of bone, then this may however require surgery. If the x-ray shows the tendon has just pulled away without a fragment of bone, a non-operative approach will yield satisfactory results in most people. A splint is applied to the front of the finger (pulp side) to straighten the joint. It is worn for 6-8 weeks constantly. It can be removed for washing, but it is vital the finger is held straight at the end finger joint by a helper; otherwise the healing tendon will become undone.
When the x-ray reveals a large bone fragment has pulled off with the tendon an operation may be required.
Surgery is done as a day case procedure usually under local anaesthetic and takes about 10 minutes. The surgery can be performed using fine wires that hold the bone fragments back in place. The wires can be inserted percutaneously through small1mm stab incisions. The wires are left in place for 4 to 6 weeks and are removed in the clinic with little discomfort
Over 90% are happy with the result. However complications can occur.
- If a splint is worn the skin may become irritated. This requires regular washing but care to keep the finger straight whilst doing this.
- This may be a recurrence of the dropped finger or what is called a swan neck deformity. This deformity is the mallet appearance of the end finger joint combined with a bending backwards of the middle knuckle joint the proximal interphalangeal joint (PIPJ). On side profile it has the appearance of a swan's neck. There are surgical options to improve both these complications.