Everyone who has experienced pain in their feet during fitness activities
knows how much this can affect technique and performance. Foot pain can be
caused by injuries to the bones, ligaments, tendons, and muscles. It is
also possible to injure one or more of the nerves that course down the
foot.


When a nerve is injured, it usually results in an alteration in sensation
called parasthesia. This may feel like 'pins and needles,' numbness, or
burning pain. Often, by eliminating the cause of the irritation, these
problems will resolve. If left unattended, more serious problems can
develop. The top of the foot, the inside of the ankle, and the toes are the
areas of the foot where athletes most commonly experience nerve problems.


MORTON'S NEUROMA


A neuroma is a thickening of a nerve that usually occurs from chronic
irritation. The most common location for a neuroma on the foot is between
the third and fourth toes. Known as a Morton's neuroma, this irritation can
be caused by repeated pressure on the ball of the foot or by abnormal foot
biomechanics, such as pronation, that causes the metatarsals to move closer
to one another.


The symptoms of a neuroma may include a burning or tingling sensation in
the ball of the foot or along the third and fourth toes. These sensations
may be decreased by removing your shoes and massaging the area, but the
pain or discomfort usually recurs upon resuming activity.


Treatment for a Morton's neuroma initially consists of using local
injections to help reduce the inflammation. In addition, a metatarsal pad
may be placed under the foot to help spread the metatarsals away from one
another, taking pressure off the nerve. In most cases, this conservative
care will alleviate the problem. In resistant cases, removal of the injured
nerve branch may be necessary and can be done on an outpatient basis.


TARSAL TUNNEL SYNDROME


People who type or work on computer keyboards are aware of a problem that
occurs in the hand and wrist called carpal tunnel. A similar problem, known
as tarsal tunnel, can occur in the foot. The tarsal tunnel is an area on
the inside of the ankle through which the posterior tibial nerve passes to
enter the foot. It branches off to help supply sensation to the inside of
the ankle and the bottom of the foot. If this area becomes inflamed, it can
result in a constriction of the nerve, causing the symptoms previously
described. The inflammation can be caused by excessive pressure on this
area due to a direct injury, swelling, or excessive pronation, which is a
rolling in of the foot.


Symptoms of tarsal tunnel syndrome usually include a burning pain along the
inside of the ankle. Additionally, there may be a sensation of a sharp,
shooting pain that goes up and down the leg or foot and even numbness along
the bottom of the foot and heel.


Once diagnosed, initial treatment will usually include the use of
anti-inflationary medication or injections to help control any
inflammation. The use of functional foot orthotics may also be prescribed
to help control any abnormal motion of the foot and ankle that may be
contributing to the problem. If the pain persists, your doctor may
recommend a surgical procedure to help relieve the stress on the nerve. In
many cases, this problem will respond to conservative treatment without
surgery.


FOOT NUMBNESS


Pain or numbness on the top (dorsum) of the foot is another common
complaint of fitness-oriented people. Coursing along the top of the foot
close to the skin are small nerve branches that supply sensation to the top
of the foot and the toes. Because these nerves are so superficial, they are
prone to irritation.


These nerves usually are injured by a shoe laced too tightly across the top
of the foot or by prominent bones or bone spurs that may develop in this
area. The irritation to this part of the foot resulting from walking,
running, or jumping will cause a feeling of burning or 'pins and needles'
across the top of the foot and radiating towards the toes. In more serious
cases, this sensation can progress to complete numbness.


Initial treatment for this problem should consist of taking pressure off
prominent areas on top of the foot by loosening the shoe laces. You can
utilize moleskin or adhesive foam to pad around prominent bone spurs to
take the pressure off this area. Larger bone spurs may need to be removed
surgically. Often, if bones spurs are the result of abnormal biomechanics,
an orthotic device may be able to slow the progression of this problem as
well as eliminate the irritation to the affected nerve.


Many nerve injuries to the foot and ankle are a result of overuse to the
area which causes temporary irritation to the nerve. Such problems can
often be treated conservatively without the need to discontinue fitness
activities for a long period of time. However, symptoms such as numbness,
burning, and parasthesias can sometimes signal more involved problems and
should be evaluated by a sports medicine physician. By seeking early
evaluation and treatment, the need for more involved treatment can usually
be prevented and you will be able to resume your activities with pain-free
feet.


Perry Julien, D.P.M., is a podiatrist specializing in the medical and
surgical treatment of foot and ankle problems at the Atlanta Foot and Ankle
Center in Atlanta, GA.