Corns and Calluses

Corns and calluses are areas of thickened skin.

• A corn is caused by pressure or fracture over bony areas and they have a central core which may cause pain if pressing on a nerve
   
• A callus is usually symptomatic of an underlying problem such as a bony deformity, style of walking or inappropriate footwear.

 

Differential diagnoses:

Assess features that distinguish from verrucas. Corns and calluses:

• tend to affect weight-bearing areas whereas verrucas can occur anywhere
   
• Are only painful on direct pressure, whereas verrucas are tender on lateral pressure. Do a pinch test and if painful it is more likely to be a verruca.

 

Causes:

• Poorly-fitting footwear
   
• Abnormal foot mechanics
  • Deformities of the feet e.g. hammer toe, claw toe
  • High levels of activity e.g. long distance running
• Consider risk factors for chronic ulceration or infection:
  • peripheral vascular disease
  • Diabetes
  • peripheral neuropathy
  • previous amputation
  • previous ulceration
  • whether the patient has impaired vision or is unable to self-care

 

Self-care measures:

• Advise well-fitting comfortable footwear or protective gloves
   
• Use a self-adhesive felt pad or padding between the toes to relieve pressure.
   
• Twice a week soak the affected area in warm water for 10-20 minutes and then use a pumice stone to pare down the thickened skin. Use a moisturising cream also to keep the skin softened.

 

Medical treatment:

• Use Keratolytic creams containing salicyclic acid or urea (available over the counter) for up to 3 months.
             - E.g. Hydromol intensive, Eucerin intensive, 10% urea cream or salactol.
   
• Continue to do self-care measures as above in between treatments
   
• Note salicyclic acid such be avoided in patients with diabetes and peripheral vascular disease.

           

If the patient has any of the following please refer to podiatry:

• Diabetes 
   
• Peripheral vascular disease
   
• If symptomatic and unresponsive to self-care measures
   
• Foot deformities requiring orthotics

If the patient has any underlying bony abnormality (e.g.  hallux valgus or lesser toe deformities please follow guidelines relating to these)

 

 

For professionals:

Medscape – Corns (Clavus)

For patients:

DermNet NZ – Corns and Calluses

Patient UK– Corns and Calluses

 

 

 

Review date – December 2023

Next review due – December 2026

Reviewing GP – Dr Madeleine Attridge