Injuries to the nail can range from a bruise under the nail to separation of the nail from the nail bed. They can be complex wounds. Permanent deformity to the nail can result.

Etiology: Most injuries to the nail arise from crushing forces, such as hammers, doors slamming on fingers, human bites, or machinery or slicing or cutting, such as knives, box cutters, or machinery, or tearing or ripping, such as stubbing a toe or catching a fingernail on an object

Clinical Features: Nail may be injured in multiple ways. Patient may have subungual haematoma (nail bruise) with painful nail, or a nail laceration i.e. cut through the nail with blood visible on the skin or a fingertip amputation or a nail avulsion or a fracture of the bone under the nail can also be associated with injuries to the nail, particularly with crushing injuries.

Diagnosis: X-ray may be required to rule out the bone injury.

Treatment: Treatment starts at the site of injury. All jewelry from the affected foot is removed. Bleeding should be stopped by applying pressure with a clean cloth. The hand or foot elevated above the level of the heart. This will help to relieve the pain. Analgesics are given to control pain. Only simple injuries like bruise can be treated without special medical care. All other major nail injuries are to be treated by specialists.

Nail injuries can be prevented by keeping nails trimmed short and by being careful during operating machines and hammers.