Foot & Ankle Nerve Conditions

Peripheral neuropathy is a condition in which nerve damage in the feet or hands leads to weakness, tingling, and numbness. When the peripheral nerves can’t relay signals to the brain, this can cause pain, usually a pins-and-needles or burning feeling, leading to a partial or total loss of sensation. Other related issues may also arise. You may not notice an injury such as a break in the skin on your foot until infection has set in. Or you may begin having issues with balance and suffer a bad fall. Peripheral neuropathy is more than just damaged nerves and it can affect your sleep and your lifestyle.

Peripheral neuropathy has many causes. It is a common complication of diabetes, due to spikes in blood sugar causing damage to the nerves. Neuropathy may also result from a direct injury, an infection (e.g. Lyme disease, HIV, shingles), a chronic condition (e.g. kidney disease, blood vessel disorders, Guillain-Barré syndrome), vitamin deficiencies, autoimmune disorders (e.g. rheumatoid arthritis, lupus), cancer, and exposure to toxins. Often problems in the lower back can affect the nerves in the lower extremities especially if stenosis (narrowing of the spinal canal that pinches the spinal cord) is present.

A neuroma is a thickening of nerves in the ball of the foot which can feel like a small mass. Patients often describe it as the feeling of perpetually having a pebble in their shoe or a wrinkle in their sock. This nerve growth may also lead to tingling, burning, pain, or numbness at the site of the neuroma. The most common location for neuromas to appear is between the third and fourth toes, under the metatarsal bones (in the ball of your foot). This is called a Morton’s neuroma. But pain radiating into the second and third toes is the second most likely location of a neuroma.

As with any nerve condition, neuromas can form for many reasons. Repeated force on the ball of the feet, such as with certain daily activities like crouching, standing on a ladder or when wearing high heels or tight shoes can lead to a neuroma. Trauma to the area may also trigger neuroma growth. Other mechanical deformities which are often inherited such as having flat feet or high arches or narrow spaces between your metatarsal heads on the balls of your feet can contribute to neuroma formation.

Seeing a medical practitioner at the first sign of pain is vital. If left untreated, neuromas will continue to enlarge and the pain worsen with time. Much of neuroma treatment is preventing further damage and relieving pressure on the painful areas. Correct footwear is critical. Choose shoes that provide plenty of cushioning and are wide enough in the toe box. Keep high heel choices below 1 ¼” if possible. Our primary method of eliminating these painful symptoms is repeated injections of a 4% alcohol and local anesthetic solution which shrinks and quiets the neuroma permanently.  Metatarsal pads as well as custom molded orthotics can often provide great relief of pain by changing foot function.

Painful neuromas that do not respond to conservative treatment may be removed by a foot and ankle surgeon. This is typically performed as an outpatient procedure with only a few weeks of recovery time. You can talk to an FAAWC podiatric surgeon at your appointment to see if surgery is right for your neuroma.

The tarsal tunnel (envision a straw inside your foot) runs on the inside of the ankle, next to the bone. It is a small space in the ankle which houses important nerves, veins, arteries, and tendons. One important nerve running through this space is the posterior tibial nerve. When this nerve is squeezed by pressure or a narrowing of the tunnel space, it is called “tarsal tunnel syndrome” and it can lead to burning and shooting pain as well as numbness into the arch and heel of the foot.

Anything that compresses the tarsal tunnel and puts pressure on the posterior tibial nerve can cause tarsal tunnel syndrome. Biomechanical deformities, such as flat feet or fallen arches, can lead to improper foot positioning which puts pressure on the inside of the ankle. Space inside the tarsal tunnel may also be narrowed by other issues such as a bone spur, cyst, or varicose vein. Additionally, ankle injuries, diabetes, and arthritis can cause swelling in the ankle, compressing the tarsal tunnel.

Treating tarsal tunnel syndrome is all about relieving the compression of the posterior tibial nerve. Resting, icing the area, and taking anti-inflammatory medications will help with many causes of tarsal tunnel syndrome. Sometimes, it’s best to support or immobilize the ankle with casting, braces, or taping. Steroid/local anesthetic injections can help reduce swelling while physical therapy can help strengthen the ankle structure and loosen pressure. Changes in footwear, sleeping and sitting habits,  and the use of orthotics is also highly recommended.

Surgery for tarsal tunnel syndrome is only necessary in chronic cases which do not respond to other treatments. Your foot and ankle surgeon may discuss the need to release the nerve pressure manually by stretching the ligament pressing against the tarsal tunnel. Your FAAWC surgeon can help determine if tarsal tunnel syndrome surgery is right for you.