Keywords:
Education and training, Education, Ultrasound-Power Doppler, Ultrasound-Colour Doppler, Ultrasound, Neuroradiology peripheral nerve, Musculoskeletal system, Anatomy
Authors:
E. Massone1, A. Muda2, D. Orlandi2, S. Perugin Bernardi2, V. Fichera3, V. Picasso2, G. Rebella1, G. Buonomenna4, M. De Cesari5, E. Silvestri1; 1Genoa/IT, 2Genova/IT, 3Catania/IT, 4Avellino/IT, 5Castelnuovo di Garfagnana/IT
DOI:
10.26044/essr2019/P-0027
Background
The posterior tibial nerve is the larger of the two terminal branches of the sciatic nerve (L4-S3).
It leaves the popliteal fossa between the heads of medial and lateral gastrocnemius muscles and then runs below the characteristic arch of the soleus muscle.
At this level the tibial nerve is lateral to popliteal vessels,
while,
proximally,
it is close to the vessels and crosses to the medial side of the artery.
Then it descends in the median plane of the fibula,
between soleus and deep ankle flexor muscles (tibialis posterior,
flexor digitorum lon- gus,
and flexor hallucis longus).
At the ankle the tibial nerve runs posterior to the medial malleolus under the flexor retinaculum that forms the tarsal tunnel.
At the level of the posterior aspect of medial malleolus,
the tibial nerve is covered by the superficial and deep fascia of the leg and lies lateral and posterior to the posterior tibial artery,
between the flexor digitorum and flexor hallucis muscles (Fig.1).
The mnemonic “Tom,
Dick,
and a Very Nervous Harry” is useful to remember the anatomical position of the tibialis posterior tendon,
flexor digitorum longus tendon,
vessels,
nerves,
and flexor hallucis longus tendon.
The tarsal tunnel contains the tibial nerve,
the tibial artery,
the flexor hallucis longus tendon,
the flexor digitorum longus tendon,
and tibialis posterior tendon (Fig.2). Once it has passed through the tunnel,
the tibial nerve branches into the lateral and medial plantar nerves,
which supplies all of the intrinsic muscles on the plantar side of the foot,
providing sensitive innervation to the medial and lateral sole,
respectively.