TARSAL TUNNEL SYNDROME
Tarsal Tunnel Syndrome refers to compression of the tibial nerve and it’s branches behind the ankle joint. Generally, the most reliable diagnostic criteria are evident on clinical exam. Signs and symptoms can include pain in the ankle, pain in the heel, numbness or tingling to the plantar aspect of the foot, and discomfort radiating into the foot. These signs and symptoms may be reproducible by increasing pressure in the area over the nerve. Tapping lightly on the nerve may also reproduce the irritation. A nerve conduction/EMG study can be useful in confirming the diagnosis, although the study has been reported to be only about 50% sensitive.
The cause of tarsal tunnel syndrome is compression of the nerves by the flexor retinaculum and muscle fascia in a confined space behind the ankle. This process is similar to carpal tunnel syndrome, which affects the median nerve at the wrist. Sometimes a cyst may also take up space in the tarsal tunnel and contribute to the irritation of the nerves. Constriction of nerves causes them to become diseased and dysfunctional, and their ability to conduct signals is severely compromised. It is important to also optimize other systemic factors that may be contributing to nerve health such as hormone, vitamin, and sugar levels. If tarsal tunnel syndrome continues to be a problem after conservative treatment, then a tarsal tunnel surgical release may be beneficial.
The aim of operative intervention is to release the tight fascia and flexor retinaculum in order to free up the nerves. This is done through an incision on the inside of the ankle. The tight flexor retinaculum is released, and the nerves are exposed and released from any constrictive tissue. Release of the tight structures may allow better blood flow to the nerves and stop progression of the disease process. Excision of any cysts also increases the chances that surgery will be effective. The nerves will generally slowly recover and the neuropathic symptoms will hopefully abate. The recovery can be a lengthy process, and incomplete recovery is often seen.
The time immediately after surgery is spent resting and elevating the leg to decrease swelling and scar tissue formation. Most patients are discharged home the same day of surgery. Stitches are generally removed around 2-3 weeks. Patients are placed in a cast or boot for the first six weeks postoperatively. The use of crutches, a walker, or a rolling knee scooter can aid with mobilization. Physcial therapy may be beneficial to regain motion and strength. Patients are generally transitioned from a walking boot into a standard shoe at 6 weeks after the operation.