A 28-year-old carpenter presents to the emergency department 6 hours after his finger was caught in a door slam. On examination, there is visible blood collection beneath the nail of the distal phalanx, marked as **A** in the diagram. The patient reports severe pain at the site. X-ray shows no underlying fracture of the distal phalanx tuft. The hematoma occupies approximately 30% of the nail surface, and the nail margins appear intact with no laceration of the nail bed. What is the most appropriate immediate management for the structure marked **A**?

Explanation

## Why Trephination of the nail to drain the hematoma and relieve pressure is right Trephination (nail trephining) is the gold standard for managing painful subungual hematoma in the acute phase (<48 hours) when the nail margins are intact and there is no underlying fracture. The procedure involves perforating the nail plate using a heated paperclip, 18-gauge needle, or electrocautery point to allow drainage of blood beneath the non-yielding nail plate. This immediately relieves the pressure-related pain and is the most appropriate first-line intervention for this clinical scenario. According to Apley 10e and Bailey & Love 28e, trephination is indicated for painful subungual hematomas regardless of size when the nail structure is stable and margins are undisrupted. ## Why each distractor is wrong - **Immediate complete nail removal and nail bed repair under local anesthesia**: Nail removal is reserved for cases where the hematoma occupies >50% of the nail surface AND the nail margins are disrupted or there is significant nail bed laceration. In this case, the hematoma is only 30% and margins are intact, making trephination alone sufficient. Modern evidence supports conservative management with trephination rather than routine nail removal. - **Observation alone with elevation and protective splinting without intervention**: While elevation and splinting are supportive measures, they do NOT address the underlying problem—the painful pressure from blood beneath the non-yielding nail plate. The patient's severe pain is an indication for active drainage via trephination, not passive observation. - **Systemic antibiotics and tetanus prophylaxis without any local intervention**: Antibiotics are not indicated for closed subungual hematoma without fracture or open injury. Tetanus prophylaxis may be updated based on history, but this does not address the acute painful hematoma itself. Local drainage is the priority. **High-Yield:** Subungual hematoma <48 hours old with intact nail margins → trephinate; >50% hematoma with disrupted margins or nail bed laceration → remove nail and repair nail bed. [cite: Apley 10e; Bailey & Love 28e]