Injuries To The Nail Bed

Share Button

A fractured femur or a gunshot wound to the chest are major injuries that affect your chances of survival in disaster settings, but not all injuries are so extreme. “Minor” injuries can also impact the efficiency of a group member off the grid.  Of these, nailbed injuries are some you’ll commonly see.

You can imagine that nailbed injuries will be more common when untrained (and perhaps careless) people perform tasks to which they’re not accustomed. The failure to use work gloves and boots may also increase the risk of mishaps.


Your fingernails and toenails are made up of protein and a tough substance called keratin. They are very similar to the claws of animals.  Any issue relating to nails is referred to as “ungual” ” (from the latin word for claw: unguis).

The nail consists of several parts:

The nail plate:  this is the hard covering of the end of your finger or toe; what you normally consider to be the nail.

The nailbed:    the skin directly under the nail plate.  Made up of dermis and epidermis just like the rest of your skin, the superficial epidermis moves along with the nail plate as it grows. Vertical grooves attach the superficial epidermis to the deep dermis.  In old folks like me, the nail plate thins out and you can see the grooves if you look closely.  Like all skin, blood vessels and nerves run through the nailbed.

The nail (germinal) matrix:  the portion or root at the base of the nail under the cuticle (the cuticle is also called the eponychium) that produces new cells for the nail plate.  You can see a portion of the matrix in the  light half-moon (the “lunula”) visible at the base of the nail plate. This is the germinal matrix (actively makes new nail cells) and determines the shape and thickness of the nail; a curved matrix produces a curved nail, a flat one produces a flat nail.


There are various types of nail injuries. Amputations and fractures may occur due to trauma, but more commonly you’ll see:

Nail bed laceration: In a nail bed laceration, the nail and underlying tissue is cut. This may occur as a result of a knife or a crush injury. These wounds will bleed and leave bruising which may take a long time to heal.

Nail bed avulsion: An avulsion occurs when your nail and nail bed is pulled off the finger. This is seen when a finger is jammed into a tight space but may be caused by various other traumatic events. This injury is very painful; so much so, that it has been used as a form of torture.

Subungual Hematoma: When bleeding occurs under the nail plate, it is often trapped and accumulates, forming what is called a “hematoma“. It’s the classic result of hitting your finger with a hammer instead of the nail. You can expect throbbing pain and some bruising. When a significant amount of blood accumulates, it may lift the nail plate.

Treating Nail Bed Avulsions And Lacerations

In normal settings, an x-ray is often performed to rule out a fracture of the digit. You won’t have such modern medical technology available off the grid. Some procedures may be performed with a good medical kit and supplies. In the case of an avulsion or laceration:

  • If available, numb the area with local anesthesia by providing a digital block (see our article:
  • Clean the nailbed thoroughly and flush out any debris.  Paint with Betadine (2% Povidone-Iodine solution) or other antiseptic solution.
  • Cover the exposed (and very sensitive) nailbed with a non-adherent (Telfa) dressing.  Some will, instead, use a non-adherent dressing with Vaseline  as a covering. Change frequently.  Avoid ordinary gauze, as it sticks tenaciously to raw areas and would be painful to remove.
  • If the nail plate is hanging on by a thread, remove it by separating it from the skin folds by using a hemostat.  You can consider placing the avulsed nail plate on the nailbed as a protective covering.  Avoid scraping off loose edges in the matrix (called debridement), as it may affect the nailbed’s ability to heal.
  • In nailbed lacerations, suture (if clean) with the thinnest gauge absorbable suture available (6-0 Vicryl is good).  Be sure to remove any nail plate tissue over the laceration so the suture repair will be complete.
  • Place a fingertip dressing.  Some will stabilize the digit with a finger splint to protect from further damage.
  • A contaminated wound will usually require antibiotics and a tetanus shot.

Treating Subungual Hematomas

If a crush injury causes a bruise (also called an “ecchymosis”), it will be painful but usually just for a short time. In this case, some ibuprofen or other pain med should help. A hematoma will continue to be painful, however, even several hours after the event.  A bruise is likely appear to brownish or blue, but a hematoma may appear a deep blue-black.

In a significant hematoma, some suggest a further procedure called “trephination”.  In this instance, a very fine drill (or a red-hot 18 gauge IV needle or paper clip) is used to make a hole in the nail plate large enough to drain the blood and relieve the pressure under the nail.  It shouldn’t be too painful if you don’t go too deep. This is an important consideration to avoid damage to the nail bed. In the worst cases, the nail plate is removed instead.

The finger must be kept clean, dry, splinted, and bandaged for a minimum of 48 hours afterwards.  Most inexperienced medics should avoid this procedure except in the most severe cases, as the pain will usually decrease over time even if you do nothing.

Nail Bed Healing

It’s important to know that damage to the base of the nail (the germinal matrix) may be difficult to completely repair, and that future nail growth may be deformed in some way.

In situations where modern medical care is available, a hand surgeon is often called in to give the injury the best chance to heal appropriately.  Even then, a higher incidence of issues such as “ingrown” nails may occur.  A completely torn-off nail will take 4-6 months to grow back.

Remember, don’t try this at home, folks, if there are qualified medical professionals available to evaluate and treat the injury.

Joe Alton MD

Dr. Alton

Learn more about nail bed injuries and 150 other medical topics in disaster or other off-grid settings with the award-winning Third Edition of The Survival Medicine Handbook. Plus, increase YOUR level of medical preparedness with medical kits and individual supplies from Nurse Amy’s entire line at!

Hey, don’t forget to check out our entire line of quality medical kits and individual supplies at Also, our Book Excellence Award-winning 700-page SURVIVAL MEDICINE HANDBOOK: THE ESSENTIAL GUIDE FOR WHEN HELP IS NOT ON THE WAY is now available in black and white on Amazon and in color and color spiral-bound versions at

Share Button
Print Friendly, PDF & Email
Survival Medicine Hour #370: Amebiasis, Nail Bed Injuries, Altitude Sickness
#369 Survival Medicine Hour: Blisters, Bacteria, Baking Soda, More