Ingrown toenail

Definition

An ingrown toenail, or onychocryptosis, occurs when the edge or corner of the toenail grows into the surrounding skin, causing pain, swelling, and potential infection. It most commonly affects the big toe (hallux).

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Etiology and Risk Factors

Causes

• Improper nail trimming (cutting nails too short or rounding edges)

• Wearing tight or ill-fitting footwear

• Toe trauma (stubbing, repetitive pressure from sports)

• Nail plate deformities or thickened nails

• Genetic predisposition (naturally curved nails)

Risk Factors

• Adolescents and young adults (higher nail growth rate, increased activity)

• Diabetes or peripheral vascular disease (impaired healing, infection risk)

• Hyperhidrosis (excessive sweating leading to soft skin around nails)

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Pathophysiology

The penetrating nail edge causes a foreign body reaction in the periungual skin, leading to inflammation, pain, and swelling. If untreated, secondary bacterial infection may occur, often with Staphylococcus aureus. Chronic cases can lead to hypertrophy of periungual tissue and granulation tissue formation.

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Clinical Features

Symptoms

• Pain and tenderness along one or both sides of the nail

• Swelling and redness at the nail fold

• Possible purulent discharge if infected

• Difficulty wearing shoes or walking comfortably

Signs

• Inflammatory swelling along the nail edge

• Granulation tissue in chronic or severe cases

• Serous or purulent drainage in infected nails

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Staging

1. Stage 1 (Mild) – Redness, slight swelling, and pain; no pus

2. Stage 2 (Moderate) – Increased pain, swelling, and possible serous or purulent drainage

3. Stage 3 (Severe) – Chronic inflammation, granulation tissue, recurrent infections, significant nail-fold hypertrophy

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Diagnosis

Diagnosis is clinical, based on:

• History of symptoms and onset

• Physical examination of the affected toe
  No imaging is typically required unless osteomyelitis is suspected in severe or recurrent infections.

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Management

Treatment depends on severity and recurrence risk.

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Stage 1 (Mild) – Conservative Management

Goals: Relieve pressure, allow nail to grow out correctly, prevent infection

• Footwear modification: Wear wide-toe box shoes or open sandals

• Warm water soaks: 15–20 minutes, 2–3 times daily to soften skin and reduce inflammation

• Cotton or dental floss packing: Place under the ingrown nail edge to lift it away from the skin; change daily

• Topical antibiotics (if superficial infection suspected):

  • Fusidic acid 2% cream – apply thinly 2–3 times daily

  • Mupirocin 2% ointment – apply thinly 2–3 times daily

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Stage 2 (Moderate) – Medical Management

If infection is present

• Oral antibiotics for 5–7 days (targeting S. aureus):

  • Flucloxacillin 500 mg orally every 6 hours

  • If penicillin-allergic: Clarithromycin 500 mg orally twice daily or Doxycycline 100 mg orally twice daily (if appropriate)

Adjunctive measures:

• Continue warm soaks and protective padding

• Avoid trauma to the nail area

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Stage 3 (Severe) – Surgical Management

Indications: Severe pain, recurrent ingrown nails, chronic infection, or failed conservative therapy

Common Procedures:

1. Partial Nail Avulsion (PNA)

   • Removal of the affected portion of the nail under local anesthesia

   • Often combined with chemical matricectomy (phenol or sodium hydroxide) to prevent regrowth of the ingrown edge

2. Total Nail Avulsion

   • Complete removal of the nail plate; rarely indicated except in severe deformities or fungal infections with concurrent ingrown edges

3. Wedge Resection

   • Removal of a wedge of soft tissue and nail matrix to reduce recurrence risk

4. Radical Nail Fold Excision (Winograd procedure)

   • Excision of the affected nail matrix and hypertrophic lateral nail fold tissue

Post-procedure care:

• Keep foot elevated for 24–48 hours

• Apply antibiotic ointment and sterile dressing daily until healed

• Analgesia: Paracetamol 500–1000 mg every 4–6 hours (max 4 g/day) or Ibuprofen 200–400 mg every 6–8 hours if not contraindicated

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Prevention

• Cut nails straight across, avoiding rounding of edges

• Avoid cutting nails too short

• Wear properly fitted shoes with adequate toe space

• Maintain foot hygiene and keep feet dry

• Treat underlying conditions (e.g., fungal nail infections) promptly

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Special Considerations

• Diabetic patients: Early intervention is crucial due to high infection risk and impaired healing; referral to podiatry is recommended

• Recurrent cases: Consider surgical intervention with matrix destruction to prevent regrowth of the problematic edge

• Children and adolescents: Conservative care is often effective; surgical procedures reserved for persistent or severe cases