Tarsal Tunnel Syndrome
The tarsal tunnel is a narrow tunnel on the inside of the ankle comprised of the bones of the ankle and the flexor retinaculum (a band of fibrous tissue). Various structures travel through this tunnel into the foot including arteries, veins, tendons and nerves.
The posterior tibial nerve is included in these structures and is the nerve typically involved in tarsal tunnel syndrome. Compression of this nerve as it travels through the tunnel may cause symptoms within the foot such as pain, numbness, tingling, hot or cold sensations or a shooting pain up the leg or down into the toes.
There are numerous causes of compression of the tibial nerve including pes planus (fallen arches), an abnormality of the structures that form the tarsal tunnel, inflammation due to an injury (e.g. ankle sprain) or systemic diseases such as diabetes or arthritis.