A mallet finger splint holds the END JOINT of the finger straight, day and night, while the tendon or bone at the fingertip heals.
A STACK splint is the prefabricated plastic sleeve most people are given first.
A CUSTOM splint is molded to your finger. No design has clearly beaten the others in studies. What decides the result is fit, skin care, and whether the tip stays straight for the whole six weeks.
This page is about the splint itself. For the injury, see mallet finger.
The options
- Stack splint: a molded plastic sleeve over the tip, sized by number. Quick and cheap, but it can rock, trap sweat and rub the nail
- Custom thermoplastic: shaped on the back or front of the finger, with the tip open to air. Better fit for unusual finger shapes, swollen joints or skin problems
- Padded aluminum: common in emergency departments. Adjustable, but it loosens and slips
The best mallet splint is the one that stays on and keeps the tip straight for six weeks without breaking the skin.
Getting the position right
- Straight, or very slightly past straight. Too far back and the skin over the joint turns white. That blanching means the blood flow is being cut off, and the skin can break down
- Middle joint free. It should bend fully, or the finger stiffens for no reason
- Snug but not tight. Swelling changes, so fit is checked in the first week
The rule that decides the outcome
The tip must NEVER bend during the splinting period.
If it does, many clinicians restart the six-week count. So when you take the splint off to wash and dry the skin:
- Rest the finger flat on a table, nail up
- Keep the tip pressed straight with your other hand, or let the table hold it
- Slide the splint off, clean and dry the skin, and slide it back on without lifting the tip
A typical timeline
- Weeks 0 to 6: splint on 24 hours a day. Skin checks daily
- Weeks 6 to 8: splint at night and for risky tasks. Gentle bending of the tip begins
- Weeks 8 to 12: weaned. A small droop that returns means the splint goes back on and you’re reviewed
A mallet finger left for several weeks before treatment is still usually splinted, often for longer.
Problems to watch for
- White, soft skin from sweat under a Stack splint
- A sore or blister over the back of the end joint
- A splint that rocks or slides off at night
- The middle joint starting to bend backwards: early swan neck changes
Get it checked if
- Skin breaks down over the joint
- The tip bent and you’re unsure whether to restart
- The X-ray showed a large bone fragment or the joint looked out of line
- The droop is back after weaning
For the thumb version, see the thumb IP splint.
This is one of dozens of splints a hand therapist makes – see what a hand therapist does for the full list.
Fit it well, keep the skin healthy, and never let the tip bend.
Every article on this site is written using the Closing Window Method: name the window your condition runs on, find where you are in it, and act while it’s still open.