A wrist drop splint holds the wrist and knuckles up when the RADIAL NERVE has stopped working, so the hand can still grip and let go.
Without it, the wrist flops down every time you try to grip, and a flexed wrist makes a weak, useless grip.
It’s worn for as long as the nerve takes to recover: weeks after a “Saturday night” compression palsy, often months after an upper arm fracture.
Why the hand stops working
- The radial nerve powers the muscles that lift the wrist, the knuckles and the thumb. See the hand nerve map
- When it fails, the wrist drops, the fingers hang at the knuckles, and the thumb can’t lift away
- Grip needs the wrist held up. Try making a hard fist with your wrist bent forwards: it’s weak. That’s what wrist drop does to every grip
- The finger joints still straighten once the knuckles are supported, because other nerves power those small muscles
Hold the wrist up and most of the grip comes back, even while the nerve is still asleep.
Common causes
- Compression at the upper arm, from sleeping with the arm hung over a chair back or pinned under a partner. Often called Saturday night palsy
- Fractures of the upper arm shaft, where the nerve wraps around the bone. See the humeral fracture brace
- Injury or compression near the elbow. When only the finger and thumb lifters are affected and the wrist still lifts, it’s a different branch. See PIN palsy
- Cuts and surgery around the arm and elbow
The splint designs
- Static wrist splint: wrist held up, fingers free. Simple, and often enough for light use
- Dynamic knuckle extension splint: slings under the fingers lift the knuckles while you grip against them. See dynamic splints
- Low-profile tenodesis splint: cords link the fingers to a forearm cuff, so gripping lifts the wrist and relaxing the grip lifts the fingers. Light enough to use all day
While the nerve recovers
- Keep the joints supple. Gently move the wrist, knuckles and thumb through their full range daily, so they’re ready when the nerve returns
- Watch for the first flicker. Recovery usually shows first in the muscles closest to the injury, then works down the arm
- Protect numb skin on the back of the thumb and hand
Typical recovery
- Compression palsy: often weeks to around three months
- After an upper arm fracture: many recover over three to six months
- No sign of recovery by around three to four months: nerve tests and a surgical opinion, sometimes followed by tendon transfers
Get it checked if
- A wrist drop appears suddenly, especially after an injury or a fracture being manipulated
- Weakness spreads or other fingers go numb
- No recovery at all after three months
- Pressure marks from the splint
This is one of dozens of splints a hand therapist makes. See what a hand therapist does for the full list.
Hold the wrist up, keep the joints moving, and give the nerve its time.
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.