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Nail Injuries

Facts on Nail Injuries

The fingernail is an important part of fingertip function. It provides support for the finger pad and improves sensation. The toenail functions in a similar manner in the foot.

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 to repair. Permanent deformity to the nail can result, even after proper repair.

The nail is a complex structure involving three different layers.

  • The nail bed is underneath the nail plate and is responsible for nail growth and support.
  • The nail plate itself is the hard substance on the back of the finger or toe.
  • The eponychium (cuticle) and lateral nail folds (raised skin on the sides of the nail) are also part of the nail unit.

What Causes Nail Injuries?

Most injuries to the nail arise from one of three mechanisms.

  • Crushing forces, such as hammers, doors slamming on fingers, human bites, or machinery
  • Slicing or cutting, such as knives, box cutters, or machinery
  • Tearing or ripping, such as stubbing a toe or catching a fingernail on an object
Medically Reviewed by a Doctor on 10/19/2016
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Patient Comments & Reviews

The eMedicineHealth doctors ask about Nail Injuries:

Nail Injury - Home Remedies

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Nail Injuries - Causes

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finger and nail problems

Subungual Hematoma: Bleeding Under the Nail


  • A subungual hematoma is a collection of blood in the space between the nail bed and fingernail
  • Subungual hematomas result from a direct injury to the fingernail.
  • The pressure generated by this collection of blood under the nail causes intense pain.

Read What Your Physician is Reading on Medscape

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