We have all jammed our finger in the door at least once and know how much it can hurt!  The most common cause of nail bed injuries and deformities is trauma. Crush injuries, where the nail bed gets squeezed between the hard nail and the distal phalanx, are common. Other injuries to the nail bed include laceration, and avulsion injuries.  The anatomy of the nail is incredible and more complex that first thought.

The nail unit consists of nail plate, nail folds, nail bed consisting of sterile and germinal matrixes and hyponychium which is located at the end of the finger.

nailbed

(Image courtesy of imgbuddy.com)

The nail bed lies underneath the hard nail plate and is responsible for the generation of the nail as well as the adherence of the nail to the finger. The nail is an important structure of the finger as it:

  • Increases sensory perception of the finger tip
  • Helps with picking up small objects
  • Protects the surface of the end of the finger
  •  Allows scratching
  •  And also has a cosmetic role.

Common injuries to the nail bed include:

Subungual haematoma may result from a crush injury, such as jamming a finger in the door. This presents as a collection of blood beneath the finger nail.

Laceration to the nail bed may occur when objects land or cut with enough force to penetrate the nail plate, for example a saw or knife.

Avulsion injuries can result from crush or grinding type injuries which result in the nail plate being removed from the nail bed and finger.

After trauma to the nail bed, there may be a nail growth delay for up to 21 days. After this time nail regeneration will increase and work on healing the injury. Nail bed healing and complete nail replacement can take up to 180 days.

Hand therapy can assist in the recovery of nail bed injuries through moulding a finger splint for protection and comfort, as well as help with wound management, finger range of motion, increasing pinch strength and desensitising the finger tip (techniques to keep the finger tip from becoming sensitive and to stop pain from becoming overbearing).  

Thank you to Laura for this blog entry, one of our recent Masters of Occupational Therapy students who spent time in our practice.