Tarsal tunnel

The tarsal tunnel is a fibro-osseous anatomical space located on the medial side of the ankle. It is bounded by the flexor retinaculum (also known as the laciniate ligament) on the medial side, the medial malleolus of the tibia anteriorly, and the calcaneus posteriorly. The tarsal tunnel serves as a passageway for several important structures.

Within the tarsal tunnel, the following structures are found:

1. Tibial nerve: This nerve bifurcates into the medial and lateral plantar nerves within the tunnel in the majority of cases.[1-2]

2. Posterior tibial artery: This artery also bifurcates within the tarsal tunnel, typically into the medial and lateral plantar arteries.[1-2]

3. Posterior tibial veins: These veins accompany the posterior tibial artery.

4. Tendons: The tendons of the tibialis posterior, flexor digitorum longus, and flexor hallucis longus muscles pass through the tarsal tunnel.

The anatomical arrangement of these structures is crucial for understanding conditions such as tarsal tunnel syndrome, where compression of the tibial nerve within this confined space can lead to neuropathic symptoms.[2-3] The variability in the bifurcation points of the tibial nerve and posterior tibial artery within the tarsal tunnel has been documented, highlighting the importance of detailed anatomical knowledge for surgical interventions.[1-2]