summary Nail Bed Injuries are the result of direct trauma to the fingertip and can be characterized into subungual hematoma, nail bed laceration, or nail bed avulsion. Diagnosis is made by careful inspection of the nail bed integrity. Treatment depends on severity and degree of nail bed injury but generally requires removal of the nail and nail bed repair. Epidemiology Incidence nail bed injuries are included under the umbrella of fingertip injuries finger tip injuries are the most common hand injuries seen in the hospital emergency department Demographics 3:1 male-to-female predominance Etiology Pathophysiology mechanisms of injury include crushing fingertip between two objects catching finger in a closing door saw injury snowblower injury direct blow from a hammer Associated conditions DIP fractures or dislocations Anatomy Nailbed and surrounding tissue perionychium nail nailbed surrounding skin paronychium lateral nail folds hyponychium skin distal distal and palmar to the nail eponychium dorsal nail fold proximal to nail fold lunula white part of the proximal nail matrix sterile soft tissue deep to nail distal to lunula adheres to nail germinal soft tissue deep to nail proximal to sterile matrix responsible for most of nail development insertion of extensor tendon is approximately 1.2 to 1.4 mm proximal to germinal matrix Presentation Symptoms pain Physical exam examine for subungual hematoma inspect nail integrity Imaging Radiographs recommended AP, lateral and oblique of finger to rule out fracture of distal phalanx Subungual Hematoma Most commonly caused by a crushing-type injury causes bleeding beneath nail Treatment drainage of hematoma by perforation indications less than 50% of nail involved techniques puncture nail using sterile needle electrocautery to perforate nail nail removal, D&I, nail bed repair indications > 50 % nail involved technique nail bed repair (see techniques) Nail Bed Lacerations Laceration of the nail and underlying nail bed usually present with the nail intact and a subungual hematoma greater than 50% of nail surface area Treatment nail removal with D&I, nail bed repair indications most cases modalities tetanus and antibiotic prophylaxis Avulsion Injuries Avulsion of nail and portion of underlying nail bed Mechanism usually caused by higher energy injuries Associated conditions commonly associated with other injuries including distal phalanx fracture if present reduction is advocated Treatment nail removal, nail bed repair, +/- fx fixation indications avulsion injury with minimal or no loss of nail matrix, with or without fracture technique always give tetanus and antibiotics fracture fixation depends on fracture type nail removal, nail bed repair, split thickness graft vs. nail matrix transfer, +/- fx fixation indications avulsion or crush injury with significant loss of nail matrix technique always give tetanus and antibiotics nail matrix transfer from adjacent injured finger or nail matrix transfer from second toe fracture fixation depends on fracture type Techniques Nail bed repair nail removal soak nail in Betadine while repairing nail bed nail bed repair repair nail bed with 6-0 or smaller absorbable suture RCT has demonstrated quicker repair time using 2-octylcyanoacrylate (Dermabond) instead of suture with comparable cosmetic and functional results splint eponychial fold splint eponychial fold with original nail, aluminum, or non-adherent gauze Complications Hook nail caused by advancement of the matrix to obtain coverage without adequate bony support Treatment remove nail and trim matrix to level of bone Split nail caused by scarring of the matrix following injury to nail bed Treatment excise scar tissue and replace nail matrix graft may be needed Prognosis Early treatment of acute injuries results in the best outcomes with minimal morbidity