One of the most common problems that I come across in my clinics are corns, so this month I thought I would talk about what they are and more importantly how to deal with them.
Corns are painful lesions on the feet caused by mechanical stress to that particular area. This increased mechanical stress can be due to pressure from foot ware or changes in the foot or the way we walk.
There are several types of corns or Helomata which comes from Greek helos, meaning stone wedge. Hard corns, heloma dura usually occur underneath the foot or on the tops or ends of the toes and may even occur under the nails or in the sides of the nails. Soft corns or heloma molle only appear between the toes and are soft due to perspiration between the toes. Vascular and neurovascular, heloma vasculare and heloma neurovasculare tend to be long standing lesions where blood vessels and nerves have become involved. Finally seed corns or helomata miliare which are not really corns at all. They are not caused by increased stress or pressure on the skin but are simply plugs or beads of cholesterol often in non weight bearing areas.
Differential diagnosis, most commonly confused with verruca which are generally not painful on direct pressure which corns are. Veruca also always have a vascular and neurological element.
Complications, neglected corns are can be prone to infections particularly due to foots close confinement in a warm humid environment and the proximity to the ground. Ulceration may also occur where there is sever mechanical stress or due to loss of sensitivity as in the case of diabetic neuropathy.
Treatment is roughly divided into two parts removal of the corn, sharp debridement where the corn is removed by a podiatrist/chiropodist with a scalpel. This should be a painless procedure and give instant relief from the ongoing discomfort.
Occasionally the use of local anaesthetic is required in the case of neurovascular corns. Once the corn is out the aim of the treatment is to prevent it returning. Here eliminating the original causes is the priority, reducing the pressure from foot ware and mechanical stress.
This may be padding to the foot in the short term. Changing footwear, insoles, orthotics or silicone guards to redistribute pressure where there have been changes in the shape and function of the foot longer term to mitigate the underlying problems.
There are of course over the counter remedies, usually in the form of corn plasters and these come in two basic types.
Foam rings, these aim to reduce the pressure on the lesion. Medicated corn plasters which contain an acid (usually salicylic acid) which aims to soften and dissolve the corn. The danger here is that if great care is not taken medicated corn plasters and liquids can dissolve healthy skin. This may not only be painful but in the case of diabetics and those with poor circulation can also be very dangerous and should be avoided.
As usual my advice is if in doubt see a podiatrist who will be able to treat the presenting problem and also work towards a longer term resolution.
Philip Mann 686912307