What is plantar wart and what causes them?
Plantar verrucae, or plantar warts as they are more commonly called, are warts that grow on the sole of the foot. While they can appear anywhere on the soles of the feet, they typically appear on the weight-bearing areas such as the heels. Plantar warts result from a viral infection to the skin caused by the common human papillomavirus which enters through small cuts and breaks on the bottom of your feet (Stirling, Handfield-Jones & Hudson 2001). Usually plantar warts are not a serious health concern, however, they can often be incredibly painful.
Who do plantar warts effect?
Plantar warts, and warts in general are incredibly common, and most people will experience one throughout their life (Stirling, Handfield-Jones & Hudson 2001). While all age groups are susceptible to plantar warts, they are by far the most common amongst children. It is estimated that the prevalence of warts is approximately 22% amongst school aged children in Australia, and there is no difference in frequency between males and females (Kilkenny et al. 1998).
What are the symptoms of a plantar wart?
To the untrained eye plantar warts may be misdiagnosed as other common skin conditions such as corns and calluses (Kang, Kim & Park 2008). Plantar warts will most often present with the following symptoms:
- Lesions or growths on the weight-bearing areas of the foot.
- A well-defined build-up of callus over the lesion.
- Small black dots throughout the lesion. These are small clotted blood vessels.
- The lesion will interrupt the normal ridges and skin lines on the sole of your foot.
- Pain when weight-bearing (Mayo Clinic 2018).
How do we treat plantar warts?
Although plantar warts can often resolve on their own, treatment is often warranted due to the pain and discomfort they cause during activities of daily living. Thankfully, for the clear majority of patient’s, plantar warts can be treated with conservative therapies. There are many different modalities for the treatment of plantar warts and the most suitable option is chosen depending on the patient’s age, site of infection, wart size, and pain tolerance (Kwok, Holland & Gibbs 2011).
While there are many treatment options out there, the ideal treatment for plantar warts should be simple, effective, have minimal side effects, and cheap. For this reason, the gold standard first line therapy is the use of topical treatments (Gibbs & Harvey 2009). Salicylic acid has been shown to be both an effective and safe treatment option with a cure rate of over 70%. There is no evidence to suggest that any other treatment methods have greater success in resolution, or a reduction in side effects (Gibbs & Harvey 2009).
Although topical treatments containing salicylic acid are recommended, for children and patients with a lower pain threshold, silver nitrate can be used as an alternative (Gibbs & Harvey 2009). However, silver nitrate has a lower cure rate, and more treatments may be required to achieve resolution.
If conservative treatments fail surgical options are also available. However, in most cases surgery is not highly recommended as it can lead to scarring on the sole of the foot which can cause further future complications.
Gibbs, S & Harvey I 2009, Topical treatments for cutaneous warts (Review), Cochrane Database of Systematic Reviews, art. no. CD001781, DOI: 10.1002/14651858.CD001781.pub2.
Kang, H, Kim, H & Park, Y 2008, ‘Differential diagnosis of plantar wart from corn, callus and healed wart with the aid of dermoscopy’, British Journal of Dermatology, vol. 60, no. 1, pp. 220-222.
Kilkenny, M, Merlin, K, Young, R & Marks R 1998, ‘The prevalence of common skin conditions in Australian school students: 1. Common, plane and plantar viral warts’, British Journal of Dermatology, vol. 138, no. 5, pp. 840-845.
Kwok, C, Holland, R & Gibbs, S 2011, ‘Efficacy of topical treatments for cutaneous warts: a meta-analysis and pooled analysis of randomized controlled trials’, British Journal of Dermatology, vol. 165, pp. 233-246.
Mayo Clinic 2018, Plantar Warts, Mayo Clinic, <https://www.mayoclinic.org/diseases-conditions/plantar-warts/symptoms-causes/syc-20352691>.
Stirling, J, Handfield-Jones, S & Hudson, P 2001, ‘Guidelines for the management of cutaneous warts’, British Journal of Dermatology, vol. 144, pp. 4-11.