Traumatic nail injuries
Traumatic nail injuries disrupt the nail unit (plate, folds, cuticle, bed, and matrix) by a discrete traumatic or chronic mechanical/irritant mechanism, producing acute or chronic paronychia, an ingrown nail, onycholysis, or a reactive periungual granuloma; diagnosis is clinical exam of the nail unit plus the inciting mechanism, with laboratory or biopsy testing reserved to exclude onychomycosis, psoriasis, or nail matrix melanoma, and treatment is warm compresses and incision and drainage for an abscess, oral antibiotics for severe paronychia, and nail avulsion and curettage for a refractory nail-bed lesion.
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What this article covers
- Overview
What it is: traumatic nail injuries are disruptions of the nail unit (plate, hyponychium, nail folds, cuticle, bed, and matrix) from a discrete traumatic event or repetitive mechanical/irritant…
- Epidemiology
Acute paronychia typically affects only one nail and is most commonly caused by Staphylococcus aureus.
- Risk factors
A breach in the cuticle from trauma or chronic maceration: the shared precipitant for acute and chronic paronychia, since an intact cuticle normally seals the nail fold against the environment.
- Pathophysiology
Cuticle disruption allows bacterial entry: trauma or maceration renders the cuticle incompetent, allowing Staphylococcus aureus to infect the nail fold and produce the painful swelling of acute paronychia.
- Clinical features
Unilateral, single-nail, tender swelling of the nail fold with a missing or dystrophic cuticle is acute paronychia, the hallmark presentation after a breach in the cuticle.
- Differential diagnosis
Nail matrix melanoma: irregular longitudinal melanonychia on a single nail, especially the thumb or great toe, with pigment extending onto the nail folds (Hutchinson sign), unlike the regular…
- Diagnosis
How the diagnosis is established: traumatic nail injury is a clinical diagnosis, made by examining the nail unit (plate, folds, cuticle, bed, matrix) and correlating the findings with a discrete…
- Management
First, for acute paronychia, apply warm compresses; if a fluctuant abscess is present, perform incision and drainage.
- Complications
Delayed diagnosis of nail matrix melanoma: attributing a single-nail, irregular, or Hutchinson-sign-positive pigmented streak to trauma rather than biopsying it delays diagnosis toward the advanced…
- Prognosis
Nail matrix melanoma prognosis is worse the later it is recognized, consistent with the roughly 2-year average diagnostic delay for acral lentiginous melanoma, making the decision to biopsy the highest-stakes call in this group.
- Prevention
Protect the cuticle from repeated trauma and maceration: wear waterproof gloves for wet work to prevent the chronic irritant exposure that drives chronic paronychia.
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