What is verruca needling?
Verruca needling is an effective treatment which elicits an inflammatory response in order to treat either long standing verrucae which have not responded to any other form of treatment or for a particularly painful verruca.
How does verruca needling work?
The verruca is caused by a virus called the Human Papilloma Virus (HPV) and it is able to survive a short time outside the body. It can resist drying out, freezing and storage outside of the host cells. To become active, it needs a host cell to infect and in the foot, this is in the upper layers of the skin called the epidermis, often entering through cuts or abrasions.
When the virus has infected the host cell, it alters the genome. When it reproduces, it produces two cells with the altered genome; those two produce four, eight, sixteen and so on until there are a sufficient number of altered cells for a verruca to become visible to the naked eye.
The only way that a verruca can be successfully treated is if every infected cell is destroyed, and the only way this can be done is through an inflammatory or antibody response. For the same reason we cannot cure the common cold and flu, we cannot cure verrucae; but the immune system can, given the chance. That is why needling is so useful.
As the virus is confined to the epidermis there is no systemic dissemination and it is thought for that reason the immune system cannot see it. Needling works by pushing the verruca cells from the epidermis through into the dermis and hypo dermis or adipose layer thereby inoculating the underlying tissue.
This triggers an immune response. The appropriate antibodies are produce and over the subsequent weeks the verruca undergoes a natural deterioration before ultimately disappearing altogether.
What does verruca needling involve?
Firstly, the podiatrist will assess the patient, undertaking a full medical history including medication taken and healing potential. The procedure with the risks and benefits are explained fully and an information booklet given to the patient. Consent forms are signed by either the patient or parent or guardian if the patient is a child. An appointment for the needling procedure is than agreed and booked.
Verruca needling is performed under a local anaesthetic with two or three injections around the ankle to ensure the foot is completely numb before proceeding. If the verruca is on a toe, a simple injection into the toe may suffice.
Once the area to be treated is completely anaesthetised a hypodermic needle is used to repeatedly puncture the verruca containing cells. This pushes verruca tissue from the epidermis through into the dermis and underlying adipose tissue layer.
What happens after needling?
Once this process has been completed a dry dressing is applied. This must be kept dry for at least 24 hours and a follow up 1 week and 8 weeks later to remove any overlying callus.
At the 8 week appointment the verruca will have usually shrunk in size if not disappeared altogether. Very rarely a second needling may have to be arranged.