Tarsal tunnel syndrome (TTS) is a type of compression neuropathy that occurs when the posterior tibial nerve and its branches (the medial plantar, lateral plantar, and calcaneal nerves), which all travel through narrow tunnels, become compressed or irritated. This can lead to pain, tingling, numbness, and other symptoms that negatively affect your overall quality of life.
People with tarsal tunnel syndrome often try to manage their pain with medication, which can be helpful in milder and earlier stages of the disease. As the condition worsens, however, medications may cease to be helpful because the root cause has not been treated. As a board-certified plastic surgeon with additional fellowship training in peripheral nerve surgery, Dr. Eric H. Williams offers tarsal tunnel treatment options that help people just like you permanently relieve their pain and get back to making the most of each day.
Symptoms of Tarsal Tunnel Syndrome
Tarsal tunnel syndrome, also known as posterior tibial neuralgia or posterior tibial nerve neuralgia, is associated with a wide range of symptoms. However, we can often diagnose tarsal tunnel syndrome based on the following:
- Persistent pain along the inside of the ankle or the sole of the foot
- Pain that is aggravated by prolonged standing, walking, or physical activity
- Tingling pain and sensations in the affected area that feel like electric shocks
- A burning sensation in the inner ankle or the sole of the foot
- Numbness or loss of sensation in the inner ankle or the sole of the foot
- Swelling in the ankle or foot
- Muscle weakness in the foot or toes that makes it challenging to perform activities that require strength and coordination, such as walking on your tiptoes or standing on one foot
- Severe refractory heel pain (in some cases)
To detect nerve dysfunction, it may be helpful to think of tarsal tunnel syndrome as similar to carpal tunnel syndrome. While carpal tunnel syndrome causes pain, tingling, numbness, and weakness in the hands, tarsal tunnel syndrome causes similar symptoms in the feet. The symptoms that really support the diagnosis of a nerve being involved as the source of the pain and that can help differentiate it from other orthopedic bone, joint, and tendon disorders, are the presence of numbness, tingling, the radiating electrical shocks, burning, or pins and needles. Dull, achy, mechanical pain with movement suggests more of the orthopedic-type pain causes.
The pain from tarsal tunnel syndrome can sometimes cause sensations of shooting pain that radiate to all parts of the sole of the foot, toes, inner ankle, or even up the calf. It may be mistaken for other conditions like plantar fasciitis, spinal stenosis, or medically treated peripheral neuropathy.
How People Develop Tarsal Tunnel Syndrome
The posterior tibial nerve is a branch of the sciatic nerve, which runs down the back of the leg and eventually divides into two branches—one of which is the posterior tibial nerve. The posterior tibial nerve primarily travels through the lower leg's posterior (back) compartment.
The posterior tibial nerve plays a crucial role in the motor and sensory functions of the lower leg and foot. It controls the muscles that help with foot inversion (turning the sole inward), ankle flexion (pushing your foot downward), and toe flexion (curling your toes down). It provides sensory innervation to the sole of the foot, which includes the ability to sense touch, pressure, temperature, and pain.
Compression of the posterior tibial nerve most often results from injury or trauma, overuse, anatomical differences, or even some medical diseases such as diabetes which causes the nerves to swell in size while the tunnels get smaller.
Diabetes can increase the risk of developing tarsal tunnel syndrome due to several factors related to the disease's effects on nerves and blood vessels.
- Diabetic neuropathy causes direct damage to the peripheral nerves making them more susceptible to compression.
- Fluid retention and inflammation within the tibial nerve itself within the tarsal tunnel causes the nerve to swell, which can then cause increased pressure on the tibial nerve.
- Impaired blood flow can result in inadequate oxygen and nutrient supply to the nerves in the tarsal tunnel.
- Elevated blood sugar levels lead to a process called glycosylation, where excess sugar molecules bind to proteins, making them more prone to compression-related issues. The fascial tunnel that is around the nerve becomes stiff and tight, thus making it more prone to squeeze and compress the nerve that is within the tunnel.
Certain anatomical variations or abnormalities can increase the risk of tarsal tunnel syndrome. These may include severely flat feet, high arches, a prominent or enlarged talus bone, varicose veins, a strongly pronated foot that rolls inward, a ganglion cyst, or bone spurs. Sometimes, there is even an extra muscle within the tarsal tunnel.
Injury or Trauma
When an injury occurs, such as an ankle sprain or a direct impact to the foot or ankle, it often results in swelling and inflammation in the affected area. As the nerve again becomes swollen within a tight tarsal tunnel, the increased pressure can compress and constrict the tibial nerve. The nerve, like any other tissue in the body, does not respond well to compression. Prolonged or excessive pressure can lead to nerve irritation and damage.
Scar tissue can also play a role in the development of tarsal tunnel syndrome. Following an injury, the body's natural response is to heal and repair damaged tissues. During this healing process, scar tissue may form in and around the tibial nerve. If this scar tissue exerts pressure on the tibial nerve, it can restrict movement and gliding to cause compression of the nerve and contribute to the development of tarsal tunnel symptoms.
Medication Isn’t Always the Answer
Medications such as nonsteroidal anti-inflammatory drugs (NSAIDs) or pain relievers (e.g., acetaminophen, oxycodone, and gabapentin) can help temporarily manage the pain associated with tarsal tunnel syndrome. However, these medications do not address the underlying cause of the condition, which is nerve compression.
They may decrease pain momentarily, but the nerve may still be dying. If the root cause of the problem is that a nerve is pinched and there is too much pressure on it, then it makes sense to take the pressure off of it. For lasting relief, you may need to surgically decompress the nerve to stop the nerve damage from progressing.
Why Dr. Williams Offers a Better Way to Treat Tarsal Tunnel Syndrome
The posterior tibial nerve runs through the tarsal tunnel and has four branches:
- Medial Plantar, affecting sensation on the inner or medial side of the foot
- Lateral Plantar, affecting sensation on the outer or lateral side of the foot
- Medial Calcaneal, affecting sensation on the inner heel
- Inferior Calcaneal, affecting sensation on the heel of the foot
Often, surgeons performing tarsal tunnel release do not decompress all four branches of the tibial nerve. Dr. Williams was fortunate to be able to participate in research designed by Dr. Gedge Rosson, a plastic surgeon and peripheral nerve surgeon at Johns Hopkins, and Dr. A. Lee Dellon, a world-renowned specialist in peripheral nerve surgery, that showed releasing the medial plantar and lateral plantar nerves significantly decreases pressure within these smaller distal tunnels and therefore should restore blood flow and function to the nerves better than the traditional approach of releasing just the tibial nerve alone at the ankle. The theory is that less pressure from outside onto the nerve leads to better blood flow inside the nerve.
To give his patients the best chance of a successful recovery, Dr. Williams releases not just the tibial nerve, but all four downstream branches of the medial plantar, lateral plantar, inferior calcaneal, and medial calcaneal nerves.
What to Expect After Surgery
Expectations are that the vast majority of patients should be able to walk with crutches immediately after surgery. Patients are generally kept non-weight bearing for about 24 hours, but then are allowed to weight bear as tolerated after 24 hours of the tarsal tunnel release surgery with the use of crutches. This is not a license to go dancing! One of Dr. Williams’ favorite rules for immediately after surgery is to “walk for your needs, not your wants” and “stop BEFORE you regret it.”
Patients will need to keep the leg elevated as much as possible to help minimize swelling. Your foot will be wrapped in a soft cotton dressing that lets you move your ankle in a protected manner, and you'll need to leave this dressing on for one week.
Your sutures will usually be taken out after three weeks. After your sutures are removed, the goal is to allow the posterior tibial nerve and its branches to glide back and forth in the scar tissue. Water walking, walking on even paved surfaces, or using an exercise bike can help you get your range of motion back.
If you had surgery on your left foot, you can drive as soon as you're no longer taking painkillers. If you had surgery on your right foot, you'll want to avoid driving for about three weeks.
How much time you'll need off work depends on the demands of your job. If you work on a computer in an office, you'll be able to return as soon as you're no longer in need of pain medication. If you have a physically demanding job that involves walking, you'll want to plan for about a minimum of four weeks off work, unless there are light-duty options for you.
Dr. Williams will explain how to care for your foot and what to expect during your recovery.
Success Rates for Surgical Tarsal Tunnel Syndrome Treatment
Individual results will vary, but the surgical treatment of tarsal tunnel syndrome results in good to excellent results for about 85% of our patients.
One of our patients, a woman diagnosed with refractory plantar fasciitis as well as tarsal tunnel syndrome, had severe symptoms that limited her daily activities. After Dr. Williams performed a tarsal tunnel release with decompression of the medial plantar, lateral plantar, and calcaneal nerves with a simultaneous plantar fascia release and lengthening of her gastrocnemius muscle, she was back to walking, standing, exercising with over 90-95% relief of her pain.
Another patient was in so much pain before visiting our office that walking and standing were impossible. Just three months after surgery, she was able to get back to playing tennis!