Subungual Hematoma with Fractured Finger: Trephination is Safe and Recommended
Yes, you can and should decompress a subungual hematoma (black nail) even when a finger fracture is present—the fracture does not contraindicate trephination, and prompt decompression significantly reduces pain and prevents further nail bed damage. 1, 2
Key Clinical Approach
Immediate Management Steps
- Obtain radiographs first to identify any associated distal phalangeal fracture, which occurs with high frequency in subungual hematomas 2
- Proceed with trephination regardless of fracture presence, as the fracture itself is not a contraindication to hematoma drainage 3, 2
- Address both conditions simultaneously: decompress the hematoma for pain relief while managing the fracture with appropriate splinting 3
Trephination Technique Selection
The method of decompression matters for safety and efficacy:
- Avoid electrocautery if acrylic nails are present, as ignition occurs in 41.5% of cases and poses burn risk 4
- Preferred technique: 18-gauge needle puncture under digital block rather than heated paper clip, which can sear underlying fluid and plug the drainage hole 5
- Alternative methods include: hollow-tip needle or electrocautery (only if no acrylic nails present) 4, 3
Fracture Management Considerations
- Most distal phalanx fractures are minimally displaced and stable, requiring only splinting after hematoma decompression 3
- Open or intra-articular fractures warrant orthopedic referral, but hematoma decompression should still be performed for pain control 3
- The presence of subungual hematoma does not change fracture management principles—treat each pathology appropriately 2
Critical Pitfalls to Avoid
- Do not delay trephination due to fracture presence: prompt decompression within hours significantly reduces pain and prevents permanent nail deformity 2
- Do not use heated paper clips: this outdated technique frequently fails due to hole plugging 5
- Do not skip radiographs: the high incidence of associated fractures makes imaging mandatory before treatment 2
Expected Outcomes and Complications
- Pain relief is immediate following successful decompression 5, 2
- Warn patients about possible complications including onycholysis, transient or permanent nail deformity, and infection—these can occur even with optimal treatment 2
- The damaged nail will grow out over 6 months (fingernails) or 12 months (toenails) 1