Treatment of Subungual Hematoma
For acute subungual hematoma causing pain, immediate drainage through nail trephination provides rapid pain relief and should be performed promptly to prevent nail bed damage and permanent nail deformity.
Immediate Management
The primary goal is rapid decompression to relieve pain and prevent complications. The accumulated blood under the nail plate creates significant pressure that, if left untreated, can damage the nail matrix and lead to permanent nail dystrophy 1.
Drainage Techniques
Multiple effective methods exist for evacuating subungual hematomas:
Hand-held cautery is a highly effective, cost-effective, and precise method that uses high temperature to burn a small hole through the nail plate painlessly, allowing blood evacuation 2
Extra-fine insulin syringe needle (29-gauge) offers an excellent alternative, particularly for smaller hematomas of the second, third, and fourth toenails where trephination is more difficult 3. The needle is inserted very close to the nail plate to minimize pain and drains blood from the hyponychium 3
Controlled nail trephination using a uniquely designed drill can penetrate the nail plate without breaching the nail bed, providing substantial pain relief within 8 hours 4
Critical Pre-Treatment Step
Radiographs must be obtained before drainage because of the high incidence of associated distal phalangeal fractures 1. This is a commonly missed step that can lead to inadequate treatment of underlying bony injury.
Timing of Intervention
Prompt decompression significantly reduces pain and prevents further damage to the nail bed and matrix 1. Athletes can typically resume activities quickly after evacuation 5.
Important Caveats and Complications
Patients must be counseled about potential complications even with optimal treatment 1:
- Onycholysis (nail separation from nail bed)
- Transient or permanent nail deformity
- Secondary infection risk
- Nail regrowth timeline: approximately 6 months for fingernails and 12 months for toenails 6
Differential Diagnosis Considerations
Before treating as simple trauma, exclude 6, 7:
- Subungual melanoma - requires different history (spontaneous onset, progressive pigmentation, lack of trauma history)
- Melanonychia - dark pigmentation without blood collection
- Onychomycosis - fungal infection with different clinical features
If there is any suspicion of melanoma rather than traumatic hematoma (particularly with atypical presentation, lack of trauma history, or irregular pigmentation), biopsy by a practitioner skilled in nail apparatus procedures is mandatory 7.