Ingrown toenail

Section: Skin and soft tissue Sub-section: Benign skin and soft tissue Curriculum: Curriculum, page 53

Definition

• A.ka. Onychocryptosis
• Occurs when a spicule of the lateral nail pierces the lateral nail fold and penetrates the skin
• Generates FB reaction with inflammatory process and often secondary infection
• Usually affects great toe
• M = F
• Affects any age

Aetiology

• Tight footwear 85% - 2nd toe – causing improperly cut nail to dig into lateral nail fold
• Improper nail trimming 65%
• Active sports people 40%
• Previous toe injury 25%
• Fungal nail infections
• Isotretinoin
• Abnormal nail shape – Pincer or Trumpet Nails

Pathophysiology

• Initial cause:
   - Excessive pressure or trauma causes the toenail edge to penetrate the adjacent skin.  - The nail edge physically injures the lateral nail fold.
• Inflammatory response:
   - Local tissue reacts with inflammation—redness, swelling, pain.
• Secondary infection:
   - Bacteria (often Staphylococcus aureus) invade the injured skin, worsening inflammation and causing pus.
• Chronicity:
   - Persistent penetration and infection lead to granulation tissue formation and hypertrophy of the lateral nail fold.
• Cycle of worsening:
   - Nail continues to embed deeper, maintaining inflammation and pain.

Classification

• Stage 1:
  • End of toe becomes reddened with mild swelling
  • Warm or painful to touch
  • No pus or drainage
• Stage 2:
  • Increasingly red, swollen and painful
  • White or yellow coloured pus or drainage from area
  • Infection may have developed
• Stage 3:
  • Granulation tissue forms and adds to swelling and pus discharge
  • Lateral nail fold hypertrophy
  • More severe infection

Management

• Lifestyle Changes

• Well-fitting shoes

• Correct nail trimming

• Allow lateral nail plate to grown beyond lateral nail fold then trim horizontally

• Management by stage

  • Stage 1 Management
    • Cotton wool – placed under lateral nail plate to prevent pressure onto lateral fold
    • Warm water soaks
    • Wash foot with soap and water
    • Topical corticosteroid cream to minimise inflammation
  • Stage 2 Management
    • Topical or oral antibiotics
    • Surgical treatment
  • Stage 3 Management
    • Surgical treatment

Surgery

• Excision of all the nail bed is not necessary
  • Growth of the nail, both in length and thickness, takes place only from the proximal part of the nail bed
  • The nail bed distal to the lunula makes no contribution and, if growth of the nail over it is prevented, it will assume the characteristics of normal skin
• LA – Ring block – Lignocaine, no adrenaline, limit volume
• Tourniquet using a Penrose drain or glove finger
• Multiple techniques
  • Best is Chemical Matrixectomy + Lateral Nail Avulsion
  • If recurrent – Total Nail Plate and Germinal Matrix removal (Zadek’s Procedure)
• Options
  • Lateral Nail Avulsion and Chemical Matrixectomy
  • Zadek’s Procedure

Great article on surgical options: Surgical Strategies for Ingrown Toenails- A Comprehensive Review of Techniques, Outcomes, and Advancements, page 1