Subungual hematoma is a commonly encountered problem in the emergency department. We designed a prospective, observational study to determine if treatment of simple subungual hematomas (SUH) by nail trephination alone is without cosmetic or infectious complications. Over a 2-year study period, 48 patients met inclusion criteria. Radiographs of all digits were taken to detect distal phalangeal fracture and SUH size was measured. Nail trephination was performed using electrocautery, and all patients reported relief of pain after the procedure. Follow-up was achieved in 45 of 48 patients with a total of 47 SUH. Average follow-up period was 10.3 +/- 4.3 months. By patient history, average time for the nail to grow back was 4.0 +/- 2.6 months. No complications of infection, osteomyelitis, or major nail deformities occurred in any patients treated by nail trephination, regardless of SUH size or presence of fracture. In simple SUH, regardless of size, nail removal with suture repair of the nail bed, as suggested in previous studies, is unnecessary.