Nail-Bed Injury

Nail-bed injuries are the most common fingertip injury seen in the ER. The nail bed — the soft tissue underneath your fingernail that grows it — gets crushed, cut, or torn off, often along with a fracture of the small bone at the tip of the finger. If the nail bed isn't repaired carefully, the scarring leaves you with a permanently deformed, split, or even absent nail. In children, an associated fracture has its own name (a Seymour fracture) and needs special handling.

The nail itself works as a natural splint over the repair — when it's still intact after the injury, your surgeon will often leave it in place or replace it over the repair to protect the new nail bed as it heals.

• Blood under the nail — a dark, painful collection of blood trapped beneath an intact nail (subungual hematoma), causing intense throbbing pressure
• Nail lifting or detachment — the nail partially or fully separates from the bed after a crush or laceration
• Visible laceration — a cut or tear in the nail bed visible through or beneath the nail, sometimes with exposed tissue
• Fingertip swelling and tenderness — the entire tip of the finger swells and throbs after the injury

Direct inspection under good lighting — your surgeon may numb the finger with a small injection first to look thoroughly. An X-ray of the finger is mandatory to check for a fracture of the bone at the tip; if the bone is broken AND the nail bed is open to the air, the wound needs to be cleaned out promptly to prevent infection of the bone.

Any cut or torn nail bed — and any nail bed injury combined with a finger-tip fracture — needs formal repair, done under magnification with very fine sutures to give the nail the best chance of growing back normally.

External patient-education references and related OSI pages for additional background:

• Britannica — Hand (anatomy)
• AAOS OrthoInfo — patient education library
• OSI glossary — orthopedic terminology in plain language