Tarsal tunnel surgery (release): recovery, results and risks

What the operation does

The tibial nerve runs behind the bony bump on the inside of the ankle, under a tough band of tissue called the flexor retinaculum. Usually within this tarsal tunnel, it divides into the medial and lateral plantar nerves, which supply the sole. The calcaneal branch to the heel usually leaves the nerve just before the tunnel. How compression there causes symptoms.

Through an incision on the inner side of the ankle, the surgeon opens the retinaculum along its length and frees the branches where they are tight. The deep fascia, or covering, of the abductor hallucis muscle along the inner edge of the foot is a second pinch point, and releasing it is considered important for a complete release. Any cyst or bony growth pressing on the nerve is removed. The operation takes about an hour, and most people go home the same day.

Who it is for

Surgery is considered when the symptoms and examination fit and non-surgical care has had a fair trial without enough relief, or sooner when a definite cause, such as a cyst pressing on the nerve, is found. Typical symptoms are burning, tingling or numbness across the sole, usually in one foot and worse with standing and walking. A positive Tinel sign, where tapping over the tunnel reproduces them, also predicts a better result.

The case is stronger when ultrasound or MRI shows something taking up room in the tunnel: a ganglion cyst, varicose veins, a lipoma or other tumor, a bony spur, or an extra (accessory) muscle. Symptoms from a lesion like this generally respond well to surgery. Nerve conduction studies can support the diagnosis, but false negatives are common, so a normal result does not rule it out. What the tests involve.

Symptoms in both feet point first toward a general neuropathy, and surgery does less well when both sides are affected. A second pressure point higher up the same nerve, called a double crush, also worsens results, so the back needs checking too. Back nerve pain versus neuropathy. Weakness or wasting of the small muscles in the sole is a reason not to wait too long.

What the results look like

Almost all of the evidence comes from case series, where surgeons report their own patients without a comparison group, so treat these numbers as a guide.

Overall. A 2024 review pooled 32 studies covering 1,115 patients. Where results were graded, 75.3 percent were excellent or good and 24.7 percent fair or poor. Success rates in individual studies range from 44 to 96 percent.

By cause. In one series in that review, 86.8 percent of people with a space-occupying lesion had an excellent or good result, against 42.9 percent of idiopathic cases, where no cause was found. A 2022 study comparing three patient series agreed: a fixed compressing structure did better than veins that swelled only intermittently, or no cause at all.

Other factors.

Second operations are less successful than first ones. In a series of 13 revisions, feet with scar tissue after an adequate first release did poorly, while those whose first release had been incomplete, without much scarring, did well.

Recovery: the typical course

Protocols differ between surgeons, and your surgeon sets the plan. The usual shape:

Diabetes, smoking and severe obesity can slow wound healing. Call your surgeon about increasing redness, swelling or drainage at the incision, a temperature above 100°F for more than four hours, or pain and numbness that are getting worse. Call promptly about new pain, swelling or warmth in the calf, which can mean a blood clot, and call 911 for chest pain or sudden shortness of breath.

Risks

Complications, most often wound problems, are reported after 6.2 to 12 percent of tarsal tunnel releases. Symptoms that persist or come back are counted separately.

• Wound problems. Slow healing, a wound that opens up, thick or tender scars, and infection.
• Nerve injury. Damage to the nerve or one of its small branches can leave new numbness or pain.
• Scar tissue around the nerve. It can bring symptoms back and makes a second operation less likely to succeed.
• Symptoms that persist or return. The 2024 review found a pooled recurrence rate of 11.2 percent, often put down to an incomplete release or to scarring.
• Complex regional pain syndrome (CRPS). A rare condition in which pain after an injury or operation stays much stronger than expected, often with skin so sensitive that light touch hurts. It is reported after this surgery, and early treatment works best.

Tarsal tunnel surgery and diabetic neuropathy

Two different operations get called nerve decompression.

A trapped tibial nerve in someone with diabetes. Single-nerve problems are more common with diabetes, so a person can have diabetic neuropathy in both feet and a compressed tibial nerve in one. The American Diabetes Association’s 2017 position statement notes that nerve entrapments may require surgical decompression. When one foot is clearly worse and the examination points to the tunnel, release is reasonable to discuss, though in a 2024 series of 53 patients, diabetes predicted pain remaining after surgery.

Decompression to treat diabetic neuropathy itself. It rests on the idea that diabetes enlarges nerves so they become trapped at several points. The procedure studied in trials releases the tibial nerve at the ankle and the peroneal nerves at the knee and on top of the foot. It remains unproven.

• American Academy of Neurology, 2006: the treatment “should be considered unproven.” The academy retired that advisory in 2024.
• Cochrane review, 2008: found no randomized trial and reached the same conclusion.
• Diabetes Care, 2007: a commentary in the American Diabetes Association’s journal said it should not be recommended for diabetic polyneuropathy until definitive randomized trials are done.
• International Working Group on the Diabetic Foot, 2023: suggests not using nerve decompression to help prevent foot ulcers.

Newer trials have not settled it. In a 2024 randomized trial of 78 people with painful diabetic neuropathy, those having surgery had one leg decompressed and a sham (placebo) operation on the other. At 12 months pain had fallen more in the surgery groups than with observation alone, but the decompressed and sham legs had improved equally. At 56 months, the decompressed legs were about 1.6 points ahead on an 11-point pain scale. The authors concluded that a placebo effect may explain part or all of the benefit. A 2026 meta-analysis of seven small, high-bias trials found lower pain scores but no evidence of better sensation or ulcer healing. It recorded wound complications in about 1 in 4 operated patients and concluded the procedure should remain investigational.

For neuropathy in both feet, decompression is not standard care. Treatments with better evidence are here. If one foot is much worse than the other, ask for it to be examined in its own right.

What to try before surgery

Most people are managed without an operation. The usual options, often combined:

• Orthoses and shoes that support the arch and stop the foot rolling inward (overpronation), which takes tension off the nerve. What to look for in a shoe.
• Less load: less standing and walking, and sometimes a night splint or walking boot for a flare.
• Physical therapy, including nerve gliding exercises and calf stretching.
• Medicines. Anti-inflammatories, topical lidocaine, or a trial of a nerve pain medicine such as gabapentin or pregabalin. How those medicines compare.
• A corticosteroid injection, which can ease symptoms and help confirm the diagnosis.
• Treating the cause. A ganglion cyst can sometimes be drained with a needle under ultrasound guidance, and conditions such as diabetes or an underactive thyroid are treated in their own right.

Questions to ask your surgeon

Take these along with our general appointment questions.

• What is pressing on my nerve, and what did the imaging show?
• Have other causes been ruled out, including my back, a general neuropathy, and heel problems such as plantar fasciitis or Baxter’s nerve?
• What will you release, the retinaculum alone or the branches in the sole too?
• What result do you expect for my cause and my symptom history?
• If I have diabetes, is this for an entrapment in one foot, or for my neuropathy in general?

Common questions

Related reading

Tarsal tunnel syndrome · Nerve conduction studies · Baxter’s neuropathy · Diabetic neuropathy · Neuropathy treatment · Appointment questions