Nail Trephination
The procedure is called nail trephination (also known as nail trephining), which involves creating a hole through the nail plate to drain a subungual hematoma and relieve pressure-related pain. 1, 2
Procedure Overview
Nail trephination is a simple, common procedure performed in emergency departments and minor injury units to provide instant relief from the severe pain caused by blood accumulation under the nail plate following crush injuries or trauma. 1
Technical Approaches
Multiple methods can be used to create the hole through the nail plate:
- Electrocautery: The most commonly studied traditional method, which uses heat to penetrate the nail plate 3
- Specialized drill devices: Uniquely designed drills that penetrate the nail plate without breaching the nail bed, providing controlled depth and minimal risk 2, 4
- Extra-fine needle technique: A 29-gauge insulin syringe needle inserted very close to the nail plate to drain blood from the hyponychium, particularly useful for smaller hematomas of the second, third, and fourth toenails where traditional trephining is more difficult 5
- Mesoscission technology: Innovative microcutting devices that create holes of specific depths in the nail plate without penetrating the nail bed 4
Clinical Outcomes
Nail trephination alone is highly effective and safe for simple subungual hematomas, regardless of size or presence of distal phalangeal fracture. 3
Evidence of Safety and Efficacy
- Patients report substantial relief of pain immediately after the procedure and over subsequent hours 2, 3
- A prospective study of 47 subungual hematomas with average 10.3-month follow-up showed no complications of infection, osteomyelitis, or major nail deformities in any patients treated by nail trephination 3
- Average time for nail regrowth was 4.0 ± 2.6 months 3
- Nail removal with suture repair of the nail bed is unnecessary for simple subungual hematomas, regardless of size 3
Important Caveats
When NOT to Perform Simple Trephination
- For painful hematomas with suspected abscess: Partial or total nail avulsion is required to access and drain the abscess, with culture of the nail bed at time of removal 6
- Signs of infection present: Look for pus, increased warmth, erythema, or purulent drainage, which may require antibiotics targeting Staphylococcus aureus and gram-positive organisms 6
Contraindications to Simple Trephination
The American College of Physicians advises against performing nail removal for simple subungual hemorrhages, reserving complete nail avulsion only for cases with suspected abscess or severe infection. 6