Tarsal Tunnel Syndrome
KEY FACTS
Terminology
Imaging
IMAGING
General Features
Tarsal tunnel is posteroinferior to medial malleolus
Tibial nerve passes deep to flexor retinaculum and divides into medial and lateral plantar branches
Medial calcaneal nerve is 1st branch of tibial nerve at ankle
Medial plantar nerve innervates abductor hallucis, flexor digitorum brevis, flexor hallucis brevis, and 1st lumbrical muscle
Lateral plantar nerve innervates remaining deep foot muscles, including quadratus plantae and abductor digiti minimi
Inferior calcaneal nerve (Baxter nerve) is 1st branch of lateral plantar nerve
dividing into the medial and lateral plantar nerves under the flexor retinaculum. The medial calcaneal nerve 
normally comes off the tibial nerve proximal to the retinaculum. The inferior calcaneal nerve 
is the 1st branch of the lateral plantar nerve.
and flexor digitorum longus 
tendons, the posterior tibial artery 
and accompanying veins, as well as the tibial nerve 
.
, accompanying veins, and the tibial nerve 
, which are about to divide into its plantar branches deep to the flexor retinaculum 
.
and lateral 
plantar nerves in the lower tarsal tunnel with accompanying veins between the abductor hallucis 
and quadratus plantae 
muscles.
