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Subungual hematoma

Rebecca K Fastle, MD
Joan Bothner, MD
Section Editors
Anne M Stack, MD
Allan B Wolfson, MD
Deputy Editor
James F Wiley, II, MD, MPH


Subungual hematoma (blood under the fingernail or toenail), a common childhood injury, is usually caused by a blow to the distal phalanx (eg, crush in a door jamb, stubbing one's toe). The blow causes bleeding of the nail bed with resultant subungual hematoma formation. Patients complain of throbbing pain and blue-black discoloration under the nail as the hematoma progresses. Pain is relieved immediately for most patients with simple nail trephination.

The trephination of subungual hematomas (ie, making a hole in the nail for drainage of blood) with intact nail fold and minimal nail or digit disruption is discussed here. The evaluation and management of distal phalanx fractures and fingertip injuries are discussed elsewhere. (See "Distal phalanx fractures" and "Management of fingertip injuries".)


Subungual hematoma refers to blood that is trapped under the nail after trauma. Subungual hematomas may be simple (ie, the nail and nail fold are intact) or accompanied by significant injuries to the nail fold and digit (eg, fingertip avulsion) [1,2].

Trephination of a subungual hematoma consists of placing one or more holes in the nail to permit drainage of blood.


Subungual hematomas may be simple (ie, the nail and nail fold are intact) (picture 1) or accompanied by significant injuries to the nail fold and digit (eg, fingertip avulsion) [1,2]. The nail matrix is the tissue under the base of the nail that permits nail growth and migration. Its longitudinal fibers anchor the dermis to the periosteum of the distal phalanx [3]. The matrix begins 7 to 8 mm under the proximal fold, and its distal end is the white crescent called the lunula. Scarring of the matrix, as occurs with nail trauma, can disrupt nail growth and lead to nail deformity or permanent loss of the nail (figure 1).

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Literature review current through: Nov 2017. | This topic last updated: Dec 05, 2016.
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  1. Roser SE, Gellman H. Comparison of nail bed repair versus nail trephination for subungual hematomas in children. J Hand Surg Am 1999; 24:1166.
  2. Ashbell TS, Kleinert HE, Putcha SM, Kutz JE. The deformed finger nail, a frequent result of failure to repair nail bed injuries. J Trauma 1967; 7:177.
  3. Patel L. Management of simple nail bed lacerations and subungual hematomas in the emergency department. Pediatr Emerg Care 2014; 30:742.
  4. Antevy PM, Saladino RA. Management of finger injuries. In: Textbook of Pediatric Emergency Procedures, 2nd, King C, Henretig FM (Eds), Lippincott Williams & Wilkins, Philadelphia 2008. p.939.
  5. Palamarchuk HJ, Kerzner M. An improved approach to evacuation of subungual hematoma. J Am Podiatr Med Assoc 1989; 79:566.
  6. Helms A, Brodell RT. Surgical pearl: prompt treatment of subungual hematoma by decompression. J Am Acad Dermatol 2000; 42:508.
  7. Bonisteel PS. Practice tips. Trephining subungual hematomas. Can Fam Physician 2008; 54:693.
  8. Kaya TI, Tursen U, Baz K, Ikizoglu G. Extra-fine insulin syringe needle: an excellent instrument for the evacuation of subungual hematoma. Dermatol Surg 2003; 29:1141.
  9. Salter SA, Ciocon DH, Gowrishankar TR, Kimball AB. Controlled nail trephination for subungual hematoma. Am J Emerg Med 2006; 24:875.
  10. Stevenson TR. Fingertip and nailbed injuries. Orthop Clin North Am 1992; 23:149.
  11. Hart RG, Kleinert HE. Fingertip and nail bed injuries. Emerg Med Clin North Am 1993; 11:755.
  12. Zook EG, Guy RJ, Russell RC. A study of nail bed injuries: causes, treatment, and prognosis. J Hand Surg Am 1984; 9:247.
  13. Batrick N, Hashemi K, Freij R. Treatment of uncomplicated subungual haematoma. Emerg Med J 2003; 20:65.
  14. Zacher JB. Management of injuries of the distal phalanx. Surg Clin North Am 1984; 64:747.
  15. Simon RR, Wolgin M. Subungual hematoma: association with occult laceration requiring repair. Am J Emerg Med 1987; 5:302.
  16. Seaberg DC, Angelos WJ, Paris PM. Treatment of subungual hematomas with nail trephination: a prospective study. Am J Emerg Med 1991; 9:209.
  17. Chung S. Minor lesions. In: Textbook of Pediatric Emergency Medicine, 7th edition, Shaw KN, Bachur RG (Eds), Wolters Kluwer, Philadelphia 2016. p.1362.
  18. Meek S, White M. Subungual haematomas: is simple trephining enough? J Accid Emerg Med 1998; 15:269.
  19. Kensinger DR, Guille JT, Horn BD, Herman MJ. The stubbed great toe: importance of early recognition and treatment of open fractures of the distal phalanx. J Pediatr Orthop 2001; 21:31.
  20. Fox IM. Osteomyelitis of the distal phalanx following trauma to the nail. A case report. J Am Podiatr Med Assoc 1992; 82:542.
  21. Gavin LA, Lanz MJ, Leung DY, Roesler TA. Chronic subungual hematomas: a presumed immunologic puzzle resolved with a diagnosis of child abuse. Arch Pediatr Adolesc Med 1997; 151:103.