Minor injuries can sometimes be a major detriment to the function of a member of your survival group. Although perhaps not as life-threatening as a gunshot wound or a fractured thighbone, nail bed injuries are common; they will be more so when we are required to perform carpentry or other duties to which we’re not accustomed.
Your fingernails and toenails are made up of protein and a tough substance called keratin. They are, as you can imagine, similar to the claws of animals. When we refer to issues involving nails, we refer to it as “ungual” (from the latin word for claw: unguis).
The nail consists of several parts:
• The nail plate (body): this is the hard covering of the end of your finger or toe; what you consider to be the nail.
• The nail bed: 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 older people, 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 nail bed.
• The nail matrix: the portion or root at the base of the nail under the cuticle 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 determines the shape and thickness of the nail; a curved matrix produces a curved nail, a flat one produces a flat nail.
In a nail “avulsion”, the nail plate is ripped away by some form of trauma. The nail may be partially or completely gone, or may be lifted up off the nail bed. Ordinarily, depending on the type of trauma, an x-ray would be performed to rule out a fracture of the digit; you won’t have this tool available without modern facilities, but you can do this for an avulsed nail:.
• Clean the nail bed thoroughly with saline solution, if available, and irrigate out any debris. Paint with Betadine (2% Povidone-Iodine solution) or other antiseptic. If you have local anesthesia, you might want to use some; this area is going to be tender.
• Cover the exposed (and very sensitive) nail bed with a non-adherent (Telfa) dressing. Some add petroleum jelly for additional protection. Change frequently. Avoid ordinary gauze, as it will stick tenaciously and be painful to remove.
• If the nail plate is hanging on by a thread, remove it by separating it from the skin folds using a small surgical clamp. You can consider placing the avulsed nail plate on the nail bed as a protective covering; it is dead tissue but may be the most comfortable option. Avoid scraping off loose edges, as it may affect the nail bed’s ability to heal.
• If the nail bed is lacerated, suture it (once cleaned) with the thinnest gauge absorbable suture available (say. 6-0 Vicryl). Be sure to remove any nail plate tissue over the laceration so the suture repair will be complete.
• Place a fingertip dressing. You might consider immobilizing the digit with a finger splint to protect it from further damage.
• Begin a course of antibiotics if the nail bed was contaminated with debris.
In some crush injuries, such as striking the nail plate with a hammer, a bruise (also called an “ecchymosis”) or a collection of blood may form underneath (a “hematoma”). A bruise will be painful, but the pain should subside within an hour or two. A hematoma, however, will continue to be painful even several hours after the event. A bruise will likely appear brownish or blue, but a hematoma may appear a deep blue-black.
For a bruised nail, little needs to be done other than giving oral pain meds, such as Ibuprofen. For a significant hematoma, however, some suggest a further procedure called “trephination”. In this instance, a very fine drill (or a hot 18 gauge needle or paper clip) is used to make a hole in the nail plate. This opening must be large enough to allow blood that has collected under the nail to escape. Once the pressure is relieved, the pain will abate.
This procedure should not be performed unless absolutely necessary, as the pain will eventually decrease over time by itself. If you go too deep through the nail, you may further injure the nail bed. The finger must be kept dry, splinted and bandaged for a minimum of 48 hours afterwards.
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 over time. A completely torn-off nail will take 4-5 months to grow back, maybe more.
Joe Alton, MD