What is the ingrown nail?

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The ingrown nail or toenail (onychocryptosis) is the condition that occurs when the side margins of the nail penetrate the skin. It is a very common pathology and tends to affect men more than women.  

A characteristic deformation of the nail plate occurs with inflammation of the soft tissues around the nail causing intense pain.  

Types of ingrown nails

Onychocryptoses are classified according to their degree of deformity and severity. Based on this, 4 stages have been established according to their degree of impact.  

  • In stage 1 the patient has pain, with oedema and inflammation.  
  • In stage 2, it becomes infected, generally with pus and an increase in the size of the soft tissues or nail walls.    
  • In stage 3, granulation tissue appears, produced by the response of the tissues to infection and/or hypertrophy of the nail walls.  
  • In stage 4, there is severe deformation of the nail plate and the nail walls.  

How many people does it affect?

Onychocryptosis is the most common toenail deformity with a prevalence of 5% of the population, although in diabetic patients this percentage can reach 30%. It is more frequent in men than in women, mainly in adolescence and youth.

Related contents

Substantiated information by:

Sergi Sánchez

Published: 1 June 2022
Updated: 1 June 2022

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