Corns are caused by
abnormal pressure and friction known as mechanical stress. This mechanical
stress, which the skin and underlying tissues are subjected to, is classified
as Compressional, Tensile, Shearing and Torsional.
This is where the tissues
of the foot are compressed between the body weight and the resistance of the
ground when walking.
This is a stretching of the
tissues of the feet on weight bearing. Elasticity of the tissues of the feet is
limited, and also diminishes with age.
This stress occurs when the
tissues of the feet are forced laterally (side to side), over the insole of the
This stress occurs when
shearing forces combine with twisting forces as the feet pivot when walking.
Most people believe that
corns have roots and if the root of the corn was removed then the corn would
never return. This is of course not the case.
Corns do not have roots!
They are a result of undue
pressure from what ever cause. The skin builds a protective hard layer wherever
pressure is exerted on the feet. This layer will become increasingly thickened
The centre of this hardened
area becomes molded into a nucleus. The nuclei of corns vary in shape and size
according to their location and stress.
Types of Corns:
1. Hard Corn. Usually located on the top of the toes or on
the sole of the foot.
2. Soft Corn. Located between the toes
where it remains constantly moist.
3. Vascular or
Neurovascular Corn. Mostly found on the sole of the foot, where blood
vessels and nerves are forced into the corn by excessive pressure.
4. Seed corns are
hard beads of fat that form only on the sole of the foot regardless of pressure
from bony prominences. They do not have surrounding callous formation and can
occur on non-weight bearing areas of the feet.
Corns can be caused by either of the
a) A Biomechanical malfunction of the
working unit of the foot.
A major cause of corns is
an abnormally working foot. When the bones of the foot are misaligned and
excessive pressure is exerted over a particular area, it can result in severe
callous and corn formation. This is frequently seen on high, and low, arched
b) Shoe pressure
Shoes play a direct role on
the formation of corns.
Shoes that are high at the
heel and narrow at the toes force the front of the feet forward and compress
the toes within the narrow space of the toe box of the shoe. This results in
corns developing between the toes, mostly the 4th and 5th toes, but can also
occur between the other toes. The majority of ladies fashionable shoes have
narrow toe boxes, irrespective of heel height. The toes are crushed in the toe
box of the shoe and corns develop on top of the toes. This is exacerbated when
walking as the crease of the shoe rubs over the top of the extended toes. If
Bunions and hammertoes are evident then the crushing scenario is worsened.
Irrespective of the fit of the shoe, i.e. Wide fitting, A fitting, EE fitting,
if the shoes have narrow constricting toe spaces, corns will develop.
The same principal as
ladies’ shoes apply. Brogues and dress shoes constrict the toes and corns
result in between, and on top of, the toes.
the Cause: Toe Box of shoes too
narrow and shallow.
the Cause: Wear shoes with toe boxes
wider and deeper.
Cure the Symptom: No pressure or friction
At times it can be very
difficult to get a properly fitting shoe. Shoes are made for the mass; they are
not made for individual needs. Therefore problems such as Bunions, retracted
toes, high arches, low arches or fallen arches are not taken into
consideration. This means that most people must squeeze their feet into shoes
that manufacturers say is the right size for them.
“I Have a Corn - How Do I Get Rid Of It?”
There are preparations
available from chemists and other outlets, which state they are for the relief
and removal of painful corns. These are medicated corn plasters that generally
contain Salicylic Acid. It is claimed that by applying these plasters,
following the manufacturers recommendations, the corn can easily be removed.
There is also a warning on such packaging, “ Not to be used by Diabetics”.
Other warnings can include, “Not to be used by the elderly, Children under 15,
or people with poor circulation. If in doubt consult the podiatrists at the
Kirkintilloch Foot Clinic.
Are Medicated Corn Plasters Safe?
Medicated corn plasters
contain a caustic that causes tissue destruction and can result in severe
inflammation, sepsis and ulceration developing on the corn site. This can be
extremely painful and be very dangerous. Manufacturers’ instructions state “Not
to be used by Diabetics”. However, there are over one million people in
this country alone who are Diabetic, but are unaware of the fact. They also
state, “ Not to be used by the elderly or people with poor circulation”.
What constitutes poor circulation? Is it arterial or venous insufficiency,
varicose veins or surface veins? Do we include swelling of the ankles or feet?
What about the vast array of drugs prescribed by a GP for heart conditions,
such as beta-blockers and vasodilators? These can cause a reduction of blood to
the extremities. Other drugs like diuretics and steroids can have adverse
affects on the skin.
Most people do not realise
that the medication they are taking can affect their circulation, and that the
restrictions mentioned on the medicated corn plaster containers actually refer
to them. Nevertheless, they can be obtained freely from chemists, and even
specialist Foot Shops, without receiving any, or very little, advice. In this
foot clinic we are seeing an increase in elderly patients 80+ with septic
conditions a result of using corn plasters. Corn plasters must not be used.
The Kirkintilloch Foot Clinic favours a
complete ban on products like these.
The podiatrist can remove
corns painlessly and safely and if the cause of the corn is removed, i.e. shoe
pressure or the feet realigned by Orthotic Therapy, then it may be possible to
eradicate the corns permanently.
DO NOT USE CORN PLASTERS.
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