Tarsal Tunnel Syndrome: An overview
If you’re experiencing heel or foot pain, identifying the cause is one of the most important steps toward healing.
Tarsal Tunnel Syndrome is a painful condition that results from a pinched nerve in the ankle — and can sometimes mimic symptoms of plantar fasciitis.
What Is Tarsal Tunnel Syndrome?
As you might imagine based on similar names alone, tarsal tunnel syndrome is similar to carpal tunnel syndrome in the wrist — but tarsal tunnel happens in the foot.
In tarsal tunnel syndrome, the tibial nerve gets pinched or trapped, leading to pain and inflammation in the “tarsal” area of the foot (the lower ankle). The entire tarsal tunnel area is full of nerves, blood vessels, and tendons. Restriction in the area is a major source of heel pain and foot pain.
Tarsal Tunnel Syndrome vs. Plantar Fasciitis
Tarsal Tunnel Syndrome is sometimes confused with plantar fasciitis. And understandably so, since both conditions can cause heel pain and often result from overuse, sudden weight gain, overpronation, high impact sports or exercises, strain, and unsupportive or worn footwear.
The biggest difference between Tarsal Tunnel Syndrome and Plantar fasciitis is the location of the damage (even though symptoms may be very similar). In Tarsal Tunnel, the inflammation, soreness and numbness results from a trapped nerve in the ankle. In plantar fasciitis, the inflammation and pain results from a damaged, deteriorating arch (the long ligament that runs along the bottom of the foot),
This means that treatment for tarsal tunnel syndrome revolves around relieving the pressure on the tibial nerve, while treatment for plantar fasciitis revolves around supporting and realigning the damaged arch.
What Causes a Trapped Nerve in the Ankle?
One of the primary causes of Tarsal Tunnel is pronation, which is when the arch of the foot rolls inward too much and collapses with each step, leading to inflammation in both the arch and ankle, which can lead to inflammation and nerve impingement over time.
Another well-known cause of Tarsal Tunnel Syndrome is arthritis, which causes inflammation in the joint of the ankle and leads to nerve damage over time.
Obesity, or sudden weight gain is another well-known cause of tibial nerve entrapment. Extra weight increases pressure on the lower third of your body, placing a lot of strain on your feet and ankles that can pinch and compress the large tibial nerve.
Heel spurs, or an abnormal growth of the heel bone, can lead to Tarsal Tunnel as well. Calcium deposits form when the plantar fascia pulls away from the heel area. The bony protrusion that develops is a heel spur. This causes you to change the way you walk to prevent discomfort and that, in turn, can lead to a pinching of the tibial nerve.
Symptoms of a Pinched Nerve from Tarsal Tunnel
The posterior tibial nerve (the nerve that gets pinched in Tarsal Tunnel) is one of the largest nerves in your foot. This nerve provides feeling to many of the muscles in your foot through the tarsal canal (a network that runs through many different arteries, tendons, and veins in your foot), which helps explain why symptoms from tarsal tunnel syndrome can be felt elsewhere in the foot (instead of just at the base of the ankle, where the posterior tibial nerve is found. Symptoms can include:
- Pain that can be described as burning, radiating, or prickling in the heel, foot, and arch
- Numbness or “pins and needles” in the heel and arch
- Pain that gets worse when you’ve been on your feet or active for a long period of time
- Pain that is worst at night while you’re trying to sleep (in contrast to plantar fasciitis, which is typically worst with the first few steps in the morning)
Can Tarsal Tunnel Cause Plantar Fasciitis?
While Tarsal Tunnel syndrome isn’t considered a cause of plantar fasciitis (or vice versa), both conditions have similar causes (as mentioned above) and can develop simultaneously.
It’s also possible for Tarsal Tunnel Syndrome to make a person more susceptible to developing plantar fasciitis. For example, Tarsal Tunnel pain from the pinched tibial nerve in one foot can cause you to rely more heavily on the other foot, placing extra strain and wear on the plantar fascia during physical activity. Likewise, tibial nerve pain may lead to gait changes that force the fascia to absorb more impact than it would otherwise.
Diagnosing and Treating Tarsal Tunnel Syndrome
Like many other foot injuries, conservative treatments for Tarsal Tunnel can go a long away toward healing. Treatments can vary, but some of the more common include:
- Healthier diet (this helps with Tarsal Tunnel that results from rapid weight gain)
- Rest from exercises that put pressure on the trapped nerve
- Massages that help improve blood flow and circulation to the ankle
- Physical therapy
- Wearing properly fitting, supportive footwear
- Tarsal tunnel surgery
- Orthotics that help stabilize the gait and realign the arch of the foot properly
- Treating any underlying ankle issues (like reduced ankle mobility), which may cause extra pinching of the nerves
- Using compression to help reduce swelling in the ankle, and reduce nerve impingement
Your doctor will diagnose Tarsal Tunnel Syndrome by taking inventory of your symptoms, doing a physical evaluation, and running additional tests as needed. Your doctor may decide to perform a nerve block, to numb the posterior tibial nerve. If the pain disappears while walking or moving, Tarsal Tunnel Syndrome is the most likely culprit (as opposed to plantar fasciitis).