The flexor retinaculum extends posteriorly and distally from the medial malleolus.

The tibial nerve passes behind the medial malleolus and beneath the flexicular retinaculum bifurcating into calcaneal and plantar branches.

Several factors may contribute to the development of tarsal tunnel neuropathy:

  • Soft tissue masses, for example lipomas, within the tendon sheath may cause compression neuropathy of the posterior tibial nerve
  • Bony prominences and exostoses may also contribute to the disorder
  • Valgus deformity of the hind foot may contribute to the neuropathy, by increasing the tensile load on the tibial nerve