Zeehan S. Husain, DPM
Charles G. Kissel, DPM
Michael S. Schey, DPM
Angela
Stoutenburg, DPM
Board
certified by the
American Board of
Podiatric Surgery.
Tarsal Tunnel Syndrome
What
Is the Tarsal Tunnel?
The
tarsal tunnel is a narrow space that lies on the inside of the ankle next
to the ankle bones.
The tunnel is covered with a thick ligament (the flexor retinaculum)
that protects and maintains the structures contained within the tunnel,
arteries, veins, tendons, and nerves.
One of these structures is the posterior tibial nerve, which is the
focus of tarsal tunnel syndrome.
What
is Tarsal Tunnel Syndrome?
Tarsal
tunnel syndrome is a compression, or squeezing, on the posterior tibial
nerve that produces symptoms anywhere along the path of the nerve.
The posterior tibial nerve runs along the inside of the ankle into
the foot.
Symptoms
Patients
with tarsal tunnel syndrome experience one or more of the following
symptoms:
 |
Tingling,
burning, or a sensation similar to an electrical shock |
|
Numbness |
|
Pain,
including shooting pain |
The
symptoms are typically felt on the inside of the ankle and/or on the
bottom of the foot. In some
people, a symptom may be isolated and occur in just one spot.
In others, it may extend to the heel, arch, toes, and even the
calf.
Sometimes
the symptoms of the syndrome appear suddenly.
Often they are brought on or aggravated by overuse of the foot,
such as in prolonged standing, walking, exercising, or beginning a new
exercise program.
It
is very important to seek early treatment if any of the symptoms of tarsal
tunnel syndrome occur. If
untreated, the condition progresses and may result in permanent nerve
damage. In addition, because
the symptoms of tarsal tunnel syndrome can be confused with other
conditions, proper evaluation is essential so that a correct diagnosis can
be made.
Causes
Tarsal
tunnel syndrome is caused by anything that produces compression on the
posterior tibial nerve, such as:
|
A
person with flat feet is at risk for developing tarsal tunnel
syndrome, because the outward tilting of the heel that occurs with
fallen arches can produce strain and compression on the nerve. |
|
An
enlarged or abnormal structure that occupies space within the tunnel
can compress the nerve. Some
examples include a varicose vein, ganglion cyst, swollen tendon, and
arthritic bone spur. |
|
An
injury, such as an ankle sprain, may produce inflammation and swelling
in or near the tunnel, resulting in compression of the nerve. |
|
A
person who is overweight may be prone to experiencing pressure on the
posterior tibial nerve. |
|
Systemic
diseases such as diabetes or arthritis can cause swelling, thus
compressing the nerve. |
Diagnosis
The
foot and ankle surgeon will examine the foot to arrive at a diagnosis and
determine if there is any loss of feeling.
During this examination, the surgeon will position the foot and tap
on the nerve to see if the symptoms can be reproduced.
He or she will also press on the area to help determine if a small
mass is present.
Sometimes
an MRI is ordered, usually if a mass is suspected or in cases where
initial treatment does not reduce the symptoms.
In addition, special studies used to evaluate nerve problems,
electromyography and nerve conduction velocity (EMG/NCV studies), may be
ordered if the condition shows no improvement with non-surgical treatment.
Treatment
A
variety of treatment options, often used in combination, are available to
treat tarsal tunnel syndrome. These
include:
|
Rest
Staying
off the foot prevents further injury and encourages healing. |
|
Ice
To
reduce swelling in the tarsal tunnel, apply a bag of ice over a thin
towel to the affected area for 20 minutes of each waking hour.
Do not put ice directly against the skin. |
|
Oral
medications
Non-steroidal
anti-inflammatory drugs (NSAID), such as ibuprofen, help reduce the
pain and inflammation. |
|
Immobilization
Restricting
movement of the foot by wearing a cast is sometimes necessary to
enable the nerve and surrounding tissue to heal. |
|
Physical
therapy
Ultrasound
therapy, exercises, and other forms of physical therapy may be
prescribed to reduce symptoms. |
|
Injection
therapy
Injections
of a local anesthetic provide pain relief, and an injected
corticosteroid may be useful in treating the inflammation. |
|
Orthotic
devices
Custom
shoe inserts may be prescribed to help maintain the arch and limit
excessive motion that can cause compression on the nerve. |
|
Shoes
Supportive
shoes, as recommended by your foot and ankle surgeon, may prove
helpful. |
|
Bracing
Patients
with flatfoot or those with severe symptoms and nerve damage may be
fitted with a brace to reduce the amount of pressure on the foot. |
|
Surgery
Sometimes
surgery is the best option for treating tarsal tunnel syndrome.
The foot and ankle surgeon will determine if surgery is
necessary and will select the appropriate procedure or procedures
based on the cause of the condition. |
