Treatment of Subungual Hematoma from Hand Trauma
For a patient with a smashed hand and subungual hematoma, perform immediate nail trephination to drain the blood collection and relieve pain—this simple procedure provides rapid relief and does not require nail removal regardless of hematoma size or presence of underlying fracture.
Immediate Assessment and Imaging
- Obtain X-rays of the affected digit to identify any distal phalangeal fractures, as these commonly accompany subungual hematomas but do not change the trephination approach 1
- Measure the size of the hematoma, though size does not dictate treatment method—trephination is appropriate for all sizes 1
- Assess for signs of open fracture or nail bed laceration requiring more extensive intervention 1
Trephination Technique Options
Three effective methods exist for draining subungual hematomas:
- Electrocautery (preferred method): Use a hand-held cautery device with a fine tip to burn a precise, small hole through the nail plate—the high temperature creates a clean opening that is essentially painless and allows immediate blood evacuation 2, 1
- Controlled drill trephination: A uniquely designed drill penetrates the nail plate without breaching the nail bed, providing quick drainage with minimal discomfort 3
- 29-gauge insulin syringe needle: Insert the extra-fine needle very close to the nail plate and drain blood from the hyponychium—this technique is particularly successful for smaller hematomas of the second, third, and fourth toenails where trephining is more difficult 4
Post-Procedure Expectations
- Patients experience substantial pain relief immediately after drainage, typically within the first 8 hours 3, 1
- Average time for complete nail regrowth is 4.0 ± 2.6 months 1
- No nail removal or nail bed repair is necessary, even for large hematomas or those with associated fractures 1
Critical Management Principle
Do not remove the nail or perform nail bed repair for simple subungual hematomas. Previous recommendations for nail removal with suture repair of the nail bed are unnecessary and increase morbidity 1. Trephination alone is sufficient treatment regardless of hematoma size or presence of distal phalangeal fracture 1.
Complications and Follow-Up
- Infection, osteomyelitis, and major nail deformities are exceedingly rare following simple trephination 1
- The procedure decreases likelihood of secondary nail dystrophy that might result from prolonged pressure on the nail matrix from accumulated blood 2
- Follow-up at 2 weeks is appropriate to ensure resolution and absence of complications 5
When to Consider Alternative Management
If there is evidence of:
- Open fracture with exposed bone
- Significant nail bed laceration visible through the nail
- Nail avulsion or partial avulsion
These scenarios may require formal nail removal and nail bed repair, but they represent complex injuries beyond simple subungual hematoma 1.