The Half Moon Nail

Subungual Haematoma

• Subungual haematomas occur when there is bleeding beneath the nail. Generally caused traumatically by getting it caught between to hard surfaces.
• The haematoma becomes trapped between the rigid structures of the nail above and the distal phalanx below.
• The space occupying mass causes intense pain secondary to increased pressure against the very sensitive nail bed and matrix.

Examination should include:

• Testing extensor and flexor tendons
• Testing circulation by capillary refill
• Checking the sensitivity to the area

Investigation:

• X-rays are generally indicated to rule out crush injury or fracture to the distal phalanx
• Document the percentage of nail bed covered by the haematoma, surrounding damage to tissues, nail-bed, and nail margins.

• Fracture to the distal phalanx
• Crush injury
• Nail bed injury
• Performing trephination on subungual ecchymosis.

If no history of trauma or story doesn’t fit with subungual haematoma consider melanoma, Kaposi’s sarcoma, and other tumors.

Wait and See:

Patients who are not experiencing significant pain at rest, should not have trephination performed, and can be treated with simple analgesia, rest, ice, and a protective splint.

Trephination:

Trephination gives good cosmetic and functional result in both adults and children as long as no other fingertip injury is present.

Trephination makes a closed wound open, and introduces the risk of bacteria entering causing infection, once procedure completed and haematoma evacuated no need to further soak digit, and a protective dressing should be applied for 7-10 to prevent infection.

LITFL: Subungual haematoma trephination. Procedure

• Bonistereel, P. (2008). Trephining subungual hematomas. Canadian Family physician. 54, 693.
• Cadogan M. Subungual haematoma trephination. LITFL
• Sherman, S. Simon’s Emergency Orthopedics 7e
• Purcell, D. Minor Injuries A Clinical Guide 3e