Tarsal Tunnel Syndrome: Why Your Inner Ankle and Sole Burn or Tingle

Most foot pain feels like an ache. Nerve pain feels different. It can burn, tingle, buzz like "pins and needles," or shoot like a small electric shock. When those feelings show up along the inside of your ankle and the bottom of your foot, one possible cause is tarsal tunnel syndrome.^1,2

Here's what it is, what can cause it, what it feels like, how it's usually treated, and why it's worth getting checked sooner rather than later.

What Is the Tarsal Tunnel?

The tarsal tunnel is a narrow space on the inside of your ankle, next to the ankle bones. A thick band of tissue called the flexor retinaculum covers it. Arteries, veins, tendons and nerves pass through it.²

One of those nerves is the tibial nerve (also called the posterior tibial nerve). It gives feeling and movement to parts of your foot.³ Inside the tunnel it splits into branches that supply the heel and the sole of the foot and toes.⁴

Tarsal tunnel syndrome happens when that nerve is squeezed (compressed) or damaged.^1,2,3 ACFAS compares it to carpal tunnel syndrome in the wrist. Both involve a nerve pinched in a tight space.²

What Does Tarsal Tunnel Syndrome Feel Like?

Symptoms are usually felt on the inside of the ankle and/or the bottom of the foot. They can spread to the heel, arch, toes or even the calf.² People describe:

• Burning or shooting pain^1,2,4
• Tingling or a "pins and needles" feeling^1,2
• Numbness on the sole of the foot^1,3,4
• Pain at the ankle, sole and toes³
• Weakness in the foot muscles, in more severe or long-lasting cases^1,3,4

Symptoms often get worse with activity, such as standing or walking for a long time.^1,2,4 StatPearls notes they often get worse at night too.⁴ In severe or long-standing cases, symptoms may become constant.¹

What Causes It?

Anything that crowds or irritates the tibial nerve can cause it. Common causes include:^1,2,3

• Foot shape. Flat feet or high arches can put pressure on the nerve. With flat feet, the heel tilts outward, which can strain the nerve.^1,2,3
• Injury. An ankle sprain or fracture can cause swelling around the nerve.^1,2,3
• Growths in the tunnel. Ganglion cysts, bone spurs, varicose veins, swollen tendons or other masses can take up space.^1,2,3
• Body-wide conditions. Diabetes, arthritis and hypothyroidism are among the conditions that can cause swelling or nerve damage.^1,2,3

Cleveland Clinic notes that for many people it is part of an overuse injury.¹ MedlinePlus lists hiking, running, hockey, ballet and other sports with sprinting and jumping as risk factors³ — worth knowing if you spend your weekends on Southwest Montana trails. In some cases, no cause is found.³

Could It Be Something Else?

Yes. Several conditions can cause pain in the same areas. These include plantar fasciitis, tendinitis, bursitis, stress fractures, Morton's neuroma, a pinched nerve in the lower back, and nerve damage from diabetes (peripheral neuropathy).^1,4 That's one reason it helps to have a podiatrist take a look rather than guessing. Our articles on heel pain causes and peripheral neuropathy cover some of these.

How Is It Diagnosed?

There is no single test just for tarsal tunnel syndrome, and the diagnosis is often made from your history and exam.⁴ A provider will usually:

• Ask about your symptoms and any past ankle injuries^1,3
• Check for loss of feeling and muscle weakness in the foot^2,3
• Gently tap over the nerve to see if it brings on tingling or pain (called a Tinel's test)^1,2
• Feel for a small lump that might be pressing on the nerve²

Depending on what they find, tests may include X-rays, ultrasound or MRI to look for a mass or injury, and nerve tests such as an electromyogram (EMG) and nerve conduction studies.^1,2,3 Blood tests may check for conditions that can damage nerves.³

How Is It Treated?

Treatment depends on the cause.³ Sources agree that nonsurgical care is usually tried first.^1,4 Options include:

• Rest and avoiding the activities that bring on symptoms^1,2,3
• Ice. Cleveland Clinic suggests ice packs for up to 20 minutes, a few times a day.¹ ACFAS advises putting a thin towel between the ice and your skin.²
• Over-the-counter anti-inflammatory medicines such as ibuprofen^1,2,3 — check with your provider first if you have other health conditions or take other medicines
• Custom orthotics and supportive shoes to support the arch and limit motion that squeezes the nerve^1,2,3
• Braces, splints or a cast to rest the foot^1,2
• Physical therapy for strength and flexibility^1,2,3
• Injections of a numbing medicine or a corticosteroid^1,2,3

If symptoms stay severe after nonsurgical treatment, surgery to release the nerve or widen the tunnel may be considered. If a mass is pressing on the nerve, it may be removed.^1,3 Results vary. StatPearls notes that relapses and incomplete relief are common, even with treatment, and that outcomes tend to be better when a clear cause is found.⁴

Why Shouldn't I Wait It Out?

Because nerves don't always bounce back. ACFAS warns that if left untreated, the condition can progress and may cause permanent nerve damage.² Cleveland Clinic adds that nerve damage "can be permanent and irreversible."¹ Without treatment, MedlinePlus notes possible complications such as foot deformity, loss of toe movement, loss of feeling in the toes or foot, and injuries you might not notice.³

The good news is that timing matters in your favor. MedlinePlus says that "early diagnosis and treatment increases the chance that symptoms can be controlled," and that a full recovery is possible if the cause is found and successfully treated.³

If you have diabetes and notice numbness or a sore on your foot, don't wait for a routine visit. Call us: Butte & Anaconda (406) 782-2278, Bozeman, Ennis & Harlowton (406) 587-8478. Learn more about diabetic foot care.

Can I Lower My Risk?

There's no guaranteed way to prevent it. Cleveland Clinic suggests a few habits that may help: space out your workouts to avoid overuse, stretch your feet and ankles regularly, warm up before exercise, and wear supportive shoes that fit well.¹

The Bottom Line

Tarsal tunnel syndrome is a pinched nerve on the inside of the ankle. It can cause burning, tingling, numbness or shooting pain along the sole of the foot, often worse with standing or walking. Rest, ice, supportive shoes and orthotics may help, and a podiatrist can look for the cause. Because untreated nerve compression can lead to lasting damage, it's worth getting checked early.

If nerve-type foot pain is slowing you down, our podiatrists can help. Request an appointment and our team will follow up within one business day. You can also find your nearest office on our locations page.

This article is for general education and isn't a substitute for medical advice. Talk with a podiatrist or your doctor about your own symptoms.

Sources

1. Tarsal Tunnel Syndrome: Symptoms, Causes & Treatment. Cleveland Clinic. my.clevelandclinic.org
2. Tarsal Tunnel Syndrome. American College of Foot and Ankle Surgeons (FootHealthFacts.org). www.foothealthfacts.org
3. Tarsal Tunnel Syndrome. MedlinePlus Medical Encyclopedia, U.S. National Library of Medicine. medlineplus.gov
4. Adler L, Bergman R, Kaiser K. Posterior Tarsal Tunnel Syndrome. StatPearls, NCBI Bookshelf. www.ncbi.nlm.nih.gov