Treating Smashed Fingers

Treating Smashed Fingers
Treating Smashed Fingers

Dr. Greene, my 15-month-old recently got her finger smashed in the door by her 2-year-old sister. I kept an eye on the nail and noticed it got yellowish, and within a week or so it had fallen off and was just attached at the cuticle. I trimmed it down as far as I could. There is a very thin nail coming in underneath. Do I keep this fingernail covered up somehow or let it breathe? How long until a new, normal, strong nail comes in?
Osmond, Nebraska


Dr. Greene’s Answer:

Slam! Smash! Slam! I vividly remember three separate finger-in-the-door episodes from my childhood. In one instance I was the culprit, inadvertently slamming a door on my friend Fernando’s finger. Twice I was the “smashee” – once with my finger caught in the door of my parents’ Chevy Nova and once in my own bedroom door.

It’s not hard to recall the shock of pain, the subsequent dull throbbing, the curious sight of the nail later falling off, and the fascination of a new, healthy nail replacing the old one. I wish the sequence could go that smoothly for all children. It doesn’t.

In the great flurry of childhood activity (don’t you wish you had some of their energy?), smashed fingers and toes are common and memorable events. Whether trapped in doors, banged by hammers, or hit by bricks, some nails re-grow beautifully while others are permanently misshapen.

With most of these accidents, swelling and bruising of the soft tissues and underlying bones are the only injuries. Soaking the finger or toe in cold water immediately after the trauma can reduce both pain and swelling. Acetaminophen or ibuprofen administered right away can also help prevent some of the pain. While taking care of these things (and administering a few hugs and kisses for good measure), you can decide whether or not your child needs to see a doctor.

Smashed fingers

When to see a doctor:

  • Blood collects under the nail, causing increasing pain.
  • The finger or toe can’t be straightened and bent easily.
  • The injury causes immediate damage to the nail, such as a visible tear below the “quick”.
  • The skin is open and may need stitches.
  • There is dirt in the wound you can’t wash out.

Sometimes blood collects under the nail — what we call a subungual hematoma. When handled properly, this does not increase or decrease the odds of the nail healing well. If enough blood is trapped to cause painful throbbing, the nail should be evaluated.

Often the physician will pierce the nail to relieve the pressure. The physician might use a red-hot paper clip, an 18-gauge needle, or an electrocautery machine. While the procedure sounds gruesome (and looks dramatic when the blood starts to spurt from the hole), most children feel great relief and no discomfort. The hot tool glides through the nail like butter.

Fractures of the bone in the fingertip are not common with this type of injury, but need special treatment if they are present. They are considered open fractures (as if the bone had come through the skin) and require treatment with antibiotics. You might suspect a fracture from the force of the blow, the appearance of the finger or toe, a lack of mobility, or persistent pain for more than three days.

As happened with your daughter, the nail will sometimes fall off days or weeks after the injury. What happens when the nail falls off? One group of investigators found that the nail grew back with excellent or very good results in 85% of those studied, with poor results in only 2%. Sometimes the new nail will look different from the original nail no matter what has been done to treat it. But, if the nail is visibly torn at the time of injury, the nail bed might need stitches. Suturing a nail bed that has been torn can dramatically increase the odds of the nail healing well.

The new fingernail will grow at an average of 1 mm per week (0.5-1.2 mm). Toenails grow at one-third to one-half this rate. Overall, four months is the average time for complete re-growth of a fingernail. Re-growth of a nail in a toddler or preschooler may only take a month or two.

In the meantime, you have done well to keep the nail remnant trimmed to avoid it catching and tearing. Be sure to keep it clean. Exposing it to the air is good, but when your daughter is playing where she might get the nail bed dirty, cover it with a lightweight bandage (perhaps with a little Betadine). See the doctor if there is any sign of infection (redness, pus, swelling, or increasing pain). While your daughter’s finger is healing, get some pictures of the process. These will help to recall the event and to marvel over the way our bodies heal.

If you have further questions about treating a smashed finger or toe, feel free to leave a comment below.

June 20, 2008
Dr. Alan Greene

Article written by

Dr. Greene is the founder of (cited by the AMA as “the pioneer physician Web site”), a practicing pediatrician, father of four, & author of Raising Baby Green & Feeding Baby Green. He appears frequently in the media including such venues as the The New York Times, the TODAY Show, Good Morning America, & the Dr. Oz Show.



  • Mary

    My daughters finger was smashed three weeks ago. I took her to the doctor and she was in antibiotics fir ten days because it was infected. Now I noticed the nail is peeling off on one side. Will it grow back? I snipped off the corner edge that was sticking up in hope to prevent it from getting snagged on anything…?

  • Renee Adams Taylor

    I am a 47 year old woman, who smashed her right index fingernail at the cuticle portion while replacing our water meter’s concrete lid. It was two months ago. Blood collected underneath my nail & wasn’t drained, so it dried under my nail. It is black in color. As it has grown, the injured area is moving downward & I see a new nail pushing it along, but there is a small separation between the old, injured nail & the new one. I have 3 questions: 1. How do I treat it? 2. What should I expect? 3. Is it common for there to be a separation between the two nails? The new nail does look healthy but bigger than the old one. Please email me a response to my questions, many thanks! :)

  • Ana Maria Maritnez

    My 6 yr old son smashed his pinky on a stall door at a store. I didnt know how serious it was so I took him to the emergency room. The doc pierced the nail with an electrical machine to release the blood. Its going on to three weeks his nail has not fallen but it is pale white in color and at the edge of the nail from where it is growing it looks GREEN! Should we be concerned? Please advise.

    • Breka Thurman

      so what happen was everything okay cuz my is like that right now

  • Anomalia

    I smashed my finger in a door, it cut the tip of the finger badly enough for it to bleed for the remainder of the day. Two days later and it’s still very stiff, moves strangely, and I have limited sensation in the entire area.

  • Breka Thurman

    my smashed my finger alost a month ago now i can see where the nail is coming off underneath but its still attached on the sides but its green by the cuticle is this normal. An its hurting pretty bad.

  • Cheryl Greene

    Most of the comments here are actually questions. Great questions. Dr. Greene can’t answer them all so we’ve added a new feature — Ask Dr. Greene!

    If you have a question, just go to and submit your question.
    Dr. Greene would love to answer every question that is asked, but he can’t (so many great questions). He can answer one question a day and he’s decided to let our readers decide which question they would most like to see answered.

    Here’s how it works – Once a day Dr. Greene will answer the question with the most votes from readers. That means, you have a better chance of getting your question answered if you invite your friends to vote.

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  • Theresa

    I got my finger mashed in between wood and metal while chopping wood. . The pad of my finger I now extremely swollen and engorged. It is swollen to capacity. What should I do to alleviate the discomfort?

  • Tracey Marie Smitt

    My son was with his babysitter and a few days ago, her two year old daughter “smashed his finger in the door.” She didnt tell me about it and I didnt find out until I happened to notice it myself. It looked like a burn. Not like his thumb had been smashed. So I asked her about it but she said it was smashed. In the past few days, the swelling has gone down and he seems to using it normally now. However, his thumb skin is peeling profusely all over. He doesnt seem to be in pain, but is the peeling normal?

    • Eric Kovak

      She lied. That is a burn. Peeling should not be a result of trauma to a finger.
      If it is smashed, you should see swelling going down after about a week, and continued bruising/coagulated blood under the nail, but no peeling.
      What this sounds like is a first degree burn. Any number of things could have happened, but I would re-address your babysitter with the knowledge she is lying.

      • Ummna

        That is not true. So, before you accuse your sitter of lying, know that my 20 month old had his finger smashed in the door almost a year ago. It never grew back the same and it did peel. I clipped this nail 3 days ago and it began peeling again!

        • Eric Kovak

          What I was focusing more on was the lack of swelling, despite the continual peeling. Your child’s finger, from what I can see in the picture, is indeed still swollen and obviously looks like a smashed finger (damage to the nail, etc.)
          I recognize now that yes, peeling is a possible result of a smashed finger.
          Peeling as a result of trauma is caused when the skin becomes so taught and swollen from edema that some of the skin cells die. This layer of dead skin then peels away.
          I will agree that it is possible that the baby sitter is telling the truth, but due to the fact that the mother is so highly suspicious of the incident, and identified the finger as looking like it was burnt, I suspected that it was something else and should be addressed with the sitter. I also listed a nice account of other symptoms of a smashed finger, and if any of those were present, a burn is increasingly less likely. If Ms. Smitt’s child’s finger looks like the one posted above, you got a nice smashed finger on your hands.

          • Ummna

            Good point! And it’s always better to go with your instinct when it comes to a child.

  • amber

    I smashed my pinkie finger on my left hand a little bit of blood has build up under the nail but it’s not black or blue it’s on the other side of my finger that has turned purple and swollen I don’t think I got the bone but it does hurt and numb what can I do?

  • Bianca Williams

    I smashed my finger on an onion chopper and i have artificial nails. Help!!

  • Meagan Beilstein

    I am a 45 year old woman that has smashed her finger last month and getting married in a month and it happens to be the finger next to my ring finger. Currently the nail bed is almost completely black but does not hurt. My question is I have been using gel nails is this ok or should I have not been wearing anything so that it can get more air to heal faster? Lastly, should I have a Dr. remove the nail as it is cracking at the bed I hope in receiving a new nail? Please email me. Many thanks!