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Wheeless' Textbook of Orthopaedics

Tibial Nerve


- See: Innerv. Musc. Lower Limb:

- Anatomy:
    - tibial nerve is derived from L4, L5, S1, S2, S3;
    - the anterior component, supplies muscles of posterior thigh (except short head of biceps whch is supplied by peroneal nerve);
    - in popliteal space it gives off branches that supply popliteus muscle, two heads of gastrocnemius ,  soleus , & plantaris muscles.
    - nerve passes into posterior compartment of leg to lie deep to the transverse crural septum;
          - here, it supplies tibialis posterior, FHL , & FDB;
    - nerve passes behind medial malleolus to plantar side of foot and divides into medial and lateral plantar nerves:

- Medial branch: counterpart of median nerve in hand;
    - innervates the first lumbricals, abductor hallucis, FDB, and flexor hallucis brevis;

- Lateral branch: counterpart of the ulnar nerve in the hand;
    - plantar muscles of the foot: are arranged in four layers w/ the FDB lying most superficially, just under plantar fascia;
    - medial and lateral branches of tibial nerve pass superficial to abductor hallucis and quadratus plantae (w/ exception of 1st branch of lateral plantar nerve);
           - at the quadratus plantae, these nerve branches changes direction from verticle to horizontal;
    - First Branch of Lateral Plantar Nerve: (Baxter's Nerve)
           - is the only branch to course deep to the abductor hallucis and FDB (but superficial to quadratus plantae) as it courses
           medially hugging the
                     medial aspect of of the calcaneus,  adjacent to the heel spur, on its way to supply the quadratus, FDB, and ADM;
           - sensory component: calcaneal periosteum, the long plantar ligament and the lateral plantar skin;
           - impingement of this nerve typically produces a Tinel's sign along the nerve branch deep to the abductor hallucis muscle;
           - nerve passes lower border of the abductor hallucis, then courses laterally, passing 5-6 mm anterior to the medial calcaneal tuberosity (or spur)
                     and then courses between the quadratus and the underlying flexor brevis, and then passes to the abductor digiti minimi;
           - references:
                     - Treatment of chronic heel pain by surgical release of the first branch of the lateral plantar nerve
                     - Nerve entrapment in painful heel syndrome 


- Posterior Nerve Block:
    - posterior tibial artery is palpated as a landmark;
    - needle is passed adjacent to the achilles tendon toward the posterior tibial artery behind the medial malleolus;
    - after aspiration, 5 ml of anesthetic is required;
    - to block posterior tibial nerve, infiltrate just medial to achilles;
    - insert the needle thru the deep fascia until it impinges on the bone behind the medial malleolus;

- Tibial Nerve Palsy:
    - w/ tibial nerve palsy foot develops:
         - cavus deformity due to plantar fascia contracture;
         - lengthening of Achilles tendon rotating calcaneus into dorsiflexion;
               - only tibialis anterior is strong enough to produce active plantar flexion in presence of paralyzed triceps surae;

- Distal Tibial Tarsal Tunnel Syndrome:



  Magnetic resonance  imaging for ineffectual tarsal tunnel surgical treatment.



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, April 10, 2012 5:24 pm