Nail bed lacerations
Nail bed lacerations should be suspected in all fingertip crush injuries. Simple or stellate nail bed lacerations without underlying fractures have a better prognosis than nail bed avulsions [3].
These injuries can be repaired by separating and removing the nail plate from the nail bed with fine scissors. The nail bed is carefully repaired with fine absorbable sutures such as Vicryl RapideĀ® 6.0. Such repair should include the dorsal roof and ventral floor of the nail fold.
The removed nail is trimmed of sharp edges and replaced in the nail fold to act as a stent for the nail bed, a template for the new nail, and as a protective cover to reduce pain and discomfort. A transverse suture through the nail and lateral folds will help retain the nail in position.
It is our practice to retain the nail for four weeks before discarding it by cutting the retaining sutures.
Nail bed lacerations with associated fractures
The nail bed is supported internally by the terminal phalanx bone and externally by the nail plate. Nail bed lacerations associated with stable undisplaced fractures of the terminal phalanx bone, which do not require internal fixation, are best managed by simple nail bed repair, as described previously, with external splintage alone.
However, displaced or unstable fractures should be referred for specialist treatment as they will require accurate reduction and internal stabilisation, usually with Kirschner wires prior to nail bed repair. Any residual dorsal step deformity of the terminal phalanx bone can result in nail bed irregularity, scarring, nail plate detachment and late nail deformity.
Learning Bite
Specialist referral is required due to a high risk of hook nail deformity in: nail bed lacerations with an underlying displaced or unstable fracture; nail bed avulsion; type III and IV fingertip injuries.
Nail bed avulsions
Nail bed avulsions may be in the form of a distally based flap with the nail attached proximally. The matrix may be detached from the underlying bone. Free segments of nail matrix may also be avulsed but still attached to the under surface of the traumatically avulsed nail.
These injuries are best referred to a hand specialist as meticulous repair (e.g. loupe magnification, nail bed grafting or rotational flap surgery) may be required.