Tibial Neuropathy



  • Tarsal tunnel syndrome


  • Denervation of affected plantar intrinsic muscles

    • Uniform high signal intensity on fluid-sensitive sequences

  • Mass in tarsal tunnel

    • Ganglion cyst: Follows fluid signal intensity, homogeneous, ± thin rim of enhancement with gadolinium

    • Nerve sheath tumor: Round or ovoid shape, often shows “tail” where it arises from nerve, diffuse enhancement

    • Venous varicosities: Serpentine, enlarged vessels in tarsal tunnel, can be followed beyond tunnel

  • Scar: Amorphous material around tibial nerve

  • Osseous impingement: Fracture malunion, subtalar coalition

Top Differential Diagnoses

  • Radiculopathy

  • Diabetic neuropathy

  • Calcaneal stress fracture

  • Plantar fasciitis

  • Isolated fatty atrophy of plantar muscles


  • Up to 50% of cases are idiopathic

Clinical Issues

  • Burning, tingling pain, numbness at plantar aspect of foot

Diagnostic Checklist

  • Fatty atrophy of plantar intrinsic muscles can be incidental finding, increasing with age

  • Intramuscular edema is most reliable sign of muscle denervation

Sagittal graphic of the medial side of the ankle shows the tibial nerve
as it courses through the tarsal tunnel, the roof of which is formed by the flexor retinaculum
. The tibial nerve is vulnerable to compression throughout its course from behind the medial malleolus to the midfoot.

Sagittal T1WI MR shows a lobular ganglion cyst
in the tarsal tunnel adjacent to the posterior tibial vein
. The patient presented with tibial neuropathy.

Sagittal T1WI MR shows a low signal intensity mass
in the tarsal tunnel. The mass has a small “tail”
, characteristic of nerve sheath tumors. At surgery, this was found to be a malignant peripheral nerve sheath tumor.

Sagittal STIR MR in the same patient shows that the mass
is heterogeneously high in signal intensity. The degree of heterogeneity is greater than expected for a synovial cyst. There is denervation edema in the abductor hallucis muscle



  • Tarsal tunnel syndrome

You're Reading a Preview

Become a Clinical Tree membership for Full access and enjoy Unlimited articles

Become membership

If you are a member. Log in here