Is your recovery window still open? Free one-page chart ↓
Stitches Close Skin. They Don’t Fix What’s Under It.
A cut on the hand or finger needs more than stitches whenever it has gone through the skin into something that MOVES or FEELS: a tendon, a nerve or an artery. If a finger won’t bend or straighten fully, feels numb along one side, or the cut spurts bright red blood, get it seen at an ER the same day.
Simple cuts with normal movement and feeling are usually closed within 6 to 12 hours and heal in about 2 weeks.
A small wound can still have cut all three. In the hand, the important structures sit only a few millimeters below the surface, so the length of the cut tells you very little about how deep it went.
Here’s the problem. A cut tendon or nerve that’s missed on day one doesn’t announce itself. The skin heals nicely, everyone relaxes, and three to six weeks later there’s a finger that won’t bend. By then the tendon ends have pulled apart and scarred, and a simple repair has become a bigger one.
Test function before you accept “it’s just a cut”.
How do I know if I cut a tendon or nerve in my finger?
Do these checks before the wound is closed, not after. Compare with the same finger on the other hand.
- Bend each joint separately. Hold the middle joint straight and bend only the tip. Then hold the base straight and bend the middle joint. A partially cut tendon can still move a finger. Testing each joint on its own is what exposes it.
- Straighten fully. A fingertip or middle joint that droops and won’t straighten on its own points at the extensor tendon on the back of the finger.
- Light touch, both sides of the finger. Each finger has two nerves, one down each edge. Numbness along ONE side is a cut digital nerve, and it’s easy to miss when the other side feels normal.
- Color and bleeding. Steady dark ooze is venous. Pulsatile bright red is arterial, and needs firm pressure and a hospital. A fingertip that’s pale, white or cold beyond the cut means its blood supply may be cut too.
- Pain on movement. Sharp pain when you bend against light resistance, at the cut, can mean a partial tendon cut even when movement looks normal.
A finger that still moves has not ruled out a tendon injury. It has only ruled out a complete one.
Tendon anatomy explains which test catches which tendon. See flexor tendon injuries by zone for the bending side and extensor tendon injuries by zone for the back of the finger.
Which hand cuts are more serious than they look?
- Glass. One of the classic causes of missed tendon and nerve injury in the hand. Glass is sharp enough to divide structures through a tiny wound, and fragments stay behind. Most glass shows on X-ray, so ask for one.
- Anything over a knuckle sustained in a fight. That’s a human bite until proven otherwise, and it goes in the emergency category regardless of size. See bites to the hand.
- High-pressure injection injuries. Paint gun, grease gun, hydraulic line. A pinhole entry, minimal pain at first, serious tissue damage within hours. This is a same-day surgical emergency, not a wound to watch.
- Palm cuts near the wrist crease. Everything crosses there: nine flexor tendons and the median nerve through the carpal tunnel, with the ulnar nerve and both arteries close by.
- Cuts on the palm side of the finger. The flexor tendons and both digital nerves sit right under the skin crease.
- Knife slips while cooking. Usually the non-knife hand, usually the palm side of the index finger or thumb. See the checks above.
(The pattern in clinic is depressingly consistent: a small clean-looking cut, glued or stitched at a walk-in clinic, and six weeks later a finger that won’t bend. By then the tendon ends have retracted and scarred.)
What should I do right after cutting my hand?
The first hour:
- Pressure. Firm, direct pressure with a clean cloth for a full 10 minutes without peeking. Hand raised above heart level.
- No tourniquets. No rubber bands or string around fingers.
- Rinse with clean running water. Don’t scrub, and don’t pour antiseptic into a deep wound.
- Rings off now, before swelling makes it a cutting-tool job.
- Amputated part: wrap in damp gauze, seal in a plastic bag, place the bag on ice. Never directly on ice, never in water. Then go. See fingertip injuries and amputations.
- Tetanus. Check when your last booster was.
Does my cut need stitches, and how soon?
- Simple, clean, superficial cuts with normal movement and feeling: closure within 6 to 12 hours. Primary care or an urgent care clinic is fine. Small cuts that gape less than a few millimeters often heal with strips or glue.
- Anything with a loss of movement, feeling or blood flow: hand surgeon. Expect the wound to be explored, often in the operating room, because the only way to be sure a tendon is intact is to look at it.
- Contaminated, bite or crush wounds are often deliberately left open, washed out and closed later. That’s correct practice, not neglect.
How long do I have to get a cut tendon or nerve repaired?
This is the window, and it closes.
- Days 0 to 7: OPEN. Tendon and nerve repairs are best done within days. The ends are fresh and easy to bring together.
- Weeks 1 to 3: CLOSING. Still usually repairable directly, but the tendon ends are retracting and the repair gets harder each week.
- After about 3 weeks: often SHUT for a simple repair. The muscle has pulled the tendon back and shortened. The goal changes: a tendon graft or a staged reconstruction instead, with a longer recovery. Function can still improve, but it’s a bigger project.
Which is why “I’ll see how it goes” is the wrong plan for a finger that won’t bend.
How long does a cut on the hand take to heal?
- Simple cut, skin only: stitches out at about 10 to 14 days on the hand. Fully comfortable for most daily tasks by 2 to 3 weeks. The scar keeps maturing for 12 months.
- Tendon repaired: protected in a splint for about 6 weeks, light use from around 6 to 8 weeks, full strength at about 12 weeks. See flexor tendon repair recovery.
- Nerve repaired: the nerve regrows roughly a millimeter a day, so feeling returns over months. A finger nerve can take 6 to 12 months, and recovery keeps creeping for up to 2 years. See nerve repair recovery.
Cold intolerance and scar hypersensitivity are normal for months after a nerve injury, and they’re the two things nobody warns people about.
Exercises after a cut finger heals
Skin-only cut: once the stitches are out and the wound is fully closed, get the finger moving.
- Full fist and full straighten. 10 reps, every 2 to 3 hours while awake.
- Tendon glides. Straight hand, hook fist, full fist, tabletop, straight fist. Hold each 3 to 5 seconds, 10 rounds, 3 to 4 times a day.
- Scar massage. Firm, 5 to 10 minutes, 2 to 3 times a day. See scar management after hand surgery.
Tendon or nerve repaired: don’t use this list. Your exercises follow your surgeon’s and hand therapist’s protocol, and the wrong exercise at week 3 can rupture a tendon repair.
When can I go back to work, drive or play sport after a hand cut?
- Skin-only cut: desk work usually the next day. Keep the wound dry until the stitches are out; no swimming or soaking until it’s healed, usually around 2 weeks. Manual work and gym once the wound is closed and gripping doesn’t hurt the scar, usually 2 to 3 weeks.
- Driving after a simple cut: once you can grip the wheel firmly and could handle an emergency stop, often within days.
- After a tendon repair: no driving while you’re in the splint. Heavy work, contact sport and gym loading usually wait until about 12 weeks.
- After a nerve repair: work around the numbness. Numb skin burns and cuts without warning, so gloves for heat, cold and sharp tools until feeling returns.
What a hand therapist does after a repaired cut
- Makes the protective splint at the right angles for the structure that was repaired.
- Runs the movement protocol, so the tendon glides without being overloaded.
- Treats the scar and swelling before they glue the tendon down.
- Retrains feeling after a nerve repair, and tracks it so you can see it returning.
The hand is dense. Everything important lives just under the surface… which is exactly why a small cut deserves a full examination rather than a quick glue.
Go to the ER now if
- Bleeding won’t stop after 10 minutes of firm direct pressure, or it’s spurting.
- The finger beyond the cut is pale, white, blue or cold.
- You can’t bend or straighten a joint, or the finger sits in an odd position at rest.
- There’s numbness on one or both sides of the finger beyond the cut.
- It was a high-pressure injection from a paint, grease or hydraulic gun, however small the hole.
- It was a fight bite over a knuckle, an animal bite, or a cut from glass.
- Part of the finger has been cut off.
Get it checked today if
- Redness spreading from the cut, increasing pain, throbbing, pus, red streaks up the forearm, or a fever.
- The whole finger is swollen, held slightly bent, and hurts to straighten. See flexor tendon sheath infection.
Get it checked if
- The finger hasn’t got its full bend or full straighten back 2 to 3 weeks after a simple cut.
- Pain when you grip, at the cut, that isn’t easing week to week.
- A tingling or numb patch that wasn’t there on day one.
- A hard, painful lump in the scar, or a feeling there’s still something inside.
Small cut, small wound, big structures underneath. Judge it by what the finger can do, not by how it looks.
Written by Nigel Chua, hand occupational therapist in practice since 2005. Thousands of hands, wrists and elbows assessed and treated. My credentials are here. This article explains; it doesn’t examine. A cut finger that won’t bend or feels numb needs a same-day assessment, not a wait-and-see.
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.