Onychophyma (Elephant Nail): Causes, Symptoms, and Treatment Options

Understanding Gross Nail Plate Hypertrophy

Onychophyma (also called “elephant nail” or “lion’s claw nail”) is a rare nail unit disorder characterized by massive thickening, curvature, and distortion of the nail plate, most often affecting toenails.

Etiology

Trauma: Chronic microtrauma (ill-fitting shoes, repetitive pressure) or acute injury to nail matrix.
Onychomycosis: Chronic fungal infection (dermatophytes) → hyperkeratosis, crumbling, secondary hypertrophy.
Psoriasis: Nail matrix inflammation → pitting, onycholysis, subungual hyperkeratosis, thickening.
Genetic/Congenital: Pachyonychia congenita (KRT6A/KRT16 mutations), congenital malalignment of great toenails.
Neoplastic: Subungual exostosis, squamous cell carcinoma, melanoma (rare but must exclude).
Systemic: Acromegaly, hypothyroidism, peripheral vascular disease, lymphedema.

Clinical Features

Marked thickening (often >2–3 mm), yellow-brown discoloration.
Longitudinal and transverse curvature (ram’s horn / oyster shell shape).
Difficulty trimming; pain with shoe pressure or walking.
Secondary onycholysis, paronychia, or ulceration of adjacent skin.

Diagnostic Workup

Clinical exam + dermatoscopy.
KOH prep / fungal culture / PCR for onychomycosis.
X-ray if exostosis or bony abnormality suspected.
Biopsy if tumor suspected (longitudinal excision including matrix).

Treatment

Approach	Indications	Details
Conservative	Mild, asymptomatic	Regular debridement (podiatry), urea 40% cream, proper footwear, treat underlying cause.
Medical	Onychomycosis, psoriasis	Oral terbinafine/itraconazole (fungal); topical/intralesional steroids, biologics (psoriasis).
Surgical	Severe pain, deformity, failed conservative	Partial/total nail avulsion ± matrix phenolization (permanent); CO₂ laser matrixectomy; excision of exostosis.

Prevention

Well-fitted shoes with wide toe box.
Prompt treatment of nail trauma/fungal infection.
Control systemic psoriasis.
Regular podiatric care for elderly/diabetic/vascular patients.

Dermatology or podiatry referral is recommended for definitive management.