Tibial Nerve

Original Editor - Lucinda hampton

Top Contributors - Lucinda hampton, Leana Louw, Nehal Shah and Rucha Gadgil

Description[edit | edit source]

The tibial nerve is the larger terminal branch of the two main muscular branches of the sciatic nerve.[1]It arises from Ventral (anterior) division of L4-5, S1-3. It travels along the distal border of the popliteus muscle, deep to gastrocnemius and soleus. In the leg, it is accompanied by the posterior tibial vessels and lies in the tarsal tunnel.[2]

The tibial nerve provides innervation to the muscles of the lower leg and foot. Specifically: triceps surae (the two headed gastocnemius and soleus), plantaris, Popliteus, tibialis posterior, flexor digitorum longus and flexor hallucis longus.[3][4] It also has articular and cutaneous branches.[5]

[6]

Nerve Root of origin[edit | edit source]

Anterior parts of the L4-S3 rami.[1]

Course of the nerve and Branches[edit | edit source]

Tibial nerve passes from the posterior aspect of the thigh and the popliteal fossa to the distal border of the popliteus muscle. It further passes deep to gastrocnemius and soleus muscles, and then anterior to the arch of soleus muscle with the popliteal artery. In the leg, the tibial nerve travels with posterior tibial vessels and lies in a fibro-osseous tunnel called the tarsal tunnel. Medially tarsal tunnel is bounded by the flexor retinaculum, laterally by the posterior aspect of talus and calcaneum, and anteriorly by the medial malleolus.[7]

There are three main branches of Tibial nerve

  • Medial Calcaneal Nerve - It arises in the ankle, traverses the flexor retinaculum and supplies posterior and lower aspect of the heel[8]. It is a sensory nerve.
  • Medial and Lateral Planter nerves - In the tarsal tunnel, Tibial nerve gives two branches - the Medial Planter Nerve (MPN) and Lateral Planter nerves (LPN)[3]. The MPN supplies muscular branches to the big toe and the two toes next to it, and the LPN the other two toes.
  • Sural Nerve - The sural nerve is a cutaneous branch of the tibial nerve that supplies the skin of the legs and feet.[4]

Anatomical Variation of Tibial Nerve Bifurcation[edit | edit source]

In the tarsal tunnel where the Tibial nerve bifurcates into the MPN and LPN, studies have found out various branching points within the Tarsal tunnel.

Anatomical Variation of branching of Tibial nerve into MPN and LPN[edit | edit source]

Malleolar-calcaneal axis (MCA) is the axis extending from medial malleolus to the medial calcaneal tuberosity. It is a reference line for classification of branching points. Based on MCA, following are the types of tibial nerve branching points[9]

  • Type I- branches proximal to the axis and within the tarsal tunnel. It is the most common pattern seen[10]
  • Type II - branches as high as the axis
  • Type III - branches at the distal end of the axis and within the tarsal tunnel
  • Type IV - branches at the proximal axis and outside the tarsal tunnel
  • Type V - branches at the distal axis and outside the tarsal tunnel

Anatomical variation in the branching of Calcaneal Nerve[edit | edit source]

Medial Calcaneal nerve is the branch of Tibial nerve with various branching points. In majority of people, Medial Calcaneal nerve originates from the Tibial nerve before it bifurcates into MPN and LPN. But in few people, it originates from the LPN (app 27%). The origin of Medial calcaneal nerve ranges from 1 cm distal to the tip of medial malleolus to 3 cm proximal to the tip[11].Another study states that The medial calcaneal nerve arises from the posterior aspect of the posterior tibial nerve in 75% of cases and from the lateral plantar nerve in 25% cases. The medial calcaneal nerve ends as a single terminal branch in 79% of cases and in numerous terminal branches in 21% cases.[12]

Inferior Calcaneal nerve originates from LPN and innervates Abductor Digiti Quinti muscle[12].

Knowledge of anatomical variations of Tibial nerve is necessary for understanding discrepancies between clinical examination and electrophysiologic tests to identify exact location of nerve lesion. Studies have shown that 60% people have multiple calcaneal branches of the tibial nerve and that 20% show previously undescribed accessory innervation to the abductor hallucis muscle from the nerve other than the medial plantar nerve[13].

Tibial Nerve.png

Function[edit | edit source]

Motor[edit | edit source]

Sensory[edit | edit source]

Branches of the tibial nerve supply sensory innervation to the following:[1]

  • Medial sural nerve supplies skin on lower half back of leg and skin of foot laterally to the little toe.
  • Medial calcaneal nerve supplies skin on posterior and inferior surface calcaneus.
  • Articular branches are to the knee (3 in total) and ankle joint.

Clinical relevance[edit | edit source]

Injury to the tibial nerve can cause motor loss and altered sensation and pain to any of the areas it supplies, depending on site of involvement.

  1. Popliteal fossa region. Injury may occur due to e.g.:
    • Space occupying lesion
    • Laceration injury
    • Posterior dislocation of the knee[14]
    • Entrapment in soleus arch: Soleus arch entrapment neuropathy can occur with sports that make special demands on the calf muscles. Swelling and hypertrophy of the soleus muscle may cause its tendinous arch to compress the popliteal artery and vein as well as the tibial nerve. This can cause chronic mechanical damage to the nerve and the artery and vein may become occluded.[15] This is requires surgical release and has a good outcome.
    • Fractures of the tibia and fibula.
    • Local trauma to the posterior lower leg.
  2. Medial malleolus level:
    • Compression of the tibial nerve in the osseofibrous tunnel below the flexor retinaculum of the ankle causes tarsal tunnel syndrome. On examination it presents as pain and paresthesia in the sole of the foot.[14]
    • Tibial nerve block done for certain operations of the foot.[16]
  3. Sole of foot:

Assessment and Treatment[edit | edit source]

For more details on the assessment and management of conditions mentioned above, see the following pages:

Entrapment in soleus arch[edit | edit source]

Physiotherapy post surgical release would include:

  • Neural mobilisation (e.g. flossing techniques)
  • Strengthening and muscle flexibility graded exercises
  • Coordination and balance training
  • Electrotherapeutic techniques (e.g. TENS) or heat may be used for pain relief.

The video below gives a good overview of the nerve and use of flossing techniques for the tibial nerve

[17]

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 1.4 Moore KL, Dalley AF, Agur AMR. Clinial oriented anatomy. Philadelphia: Wolters Kluwer, 2010.
  2. Banik Sr S, Guria LR, Banik S, Guria Sr LR. Variable branching pattern of tibial nerve in the tarsal tunnel: a gross anatomical study with clinical implications. Cureus. 2021 Mar 6;13(3).
  3. 3.0 3.1 KenHub. Tibial nerve. Available from: https://www.kenhub.com/en/library/anatomy/tibial-nerve (last accessed 17/3/2019).
  4. 4.0 4.1 Healthline. Tibial nerve. Available from: https://www.healthline.com/human-body-maps/tibial-nerve#1 (last accessed 17/03/2019).
  5. Wikipedia. The tibial nerve. Available from: https://en.wikipedia.org/wiki/Tibial_nerve (last accessed 18/03/2019).
  6. nabi lebraheim. Nerves of the lower leg 3D. Available from: https://www.youtube.com/watch?v=yPJ9sxUubRI (last accessed 17/03/2019).
  7. Williams PL. Grey's Anatomy 38th Edition, 1999 Churchill Livingstone. Page--846.
  8. Malar D. A study of tibial nerve bifurcation and branching pattern of calcaneal nerve in the tarsal tunnel. Int J Anat Res. 2016;4(1):2034-6.
  9. Soetoko AS, Fatmawati D. Anatomical variations of the tibial nerve and their clinical correlation. Anatomy & Cell Biology. 2023 Dec 12;56(4):415.
  10. Priya A, Ghosh SK, Walocha JA, Tubbs RS, Iwanaga J. Variations in the branching pattern of tibial nerve in foot: a review of literature and relevant clinical anatomy. Folia Morphologica. 2022 Apr 20.
  11. Kim BS, Choung PW, Kwon SW, Kim DH. Branching patterns of medial and inferior calcaneal nerves around the tarsal tunnel. Annals of Rehabilitation Medicine. 2015 Feb 28;39(1):52-5.
  12. 12.0 12.1 Martín-Oliva X, Elgueta-Grillo J, Veliz-Ayta P, Orosco-Villaseñor S, Elgueta-Grillo M, Viladot-Perice R. Anatomical variants of the medial calcaneal nerve and the Baxter nerve in the tarsal tunnel. Acta ortopedica mexicana. 2013;27(1):38-42.
  13. Davis TJ, Schon LC. Branches of the tibial nerve: anatomic variations. Foot & ankle international. 1995 Jan;16(1):21-9.
  14. 14.0 14.1 Earth's Lab. Tibial nerve. Available from: https://www.earthslab.com/anatomy/tibial-nerve/ (last accessed 18/03/2019).
  15. Thetter O. Entrapment Syndrome by the Tendinous Arch of the Soleus Muscle (“Soleus Syndrome”). In: Heberer G, Van Dongen RJAM, editors. Vascular Surgery. , Berlin/Heidelberg: Springer, 1989.
  16. Wassef MR. Posterior tibial nerve block: a new approach using the bony landmark of the sustentaculum tali. Anaesthesia 1991;46(10):841-4.
  17. Brian Abelson. Flossing the Tibial Nerve. Available from: https://www.youtube.com/watch?v=Ak6IHdIjnVA (last accessed 18/03/2019).