Tarsal Tunnel Syndrome

Definition:

o Compressive neuropathy of posterior tibial nerve behind medial malleolus

Symptoms & Signs:

o Poorly localized dysesthesias in plantar aspect of foot

o Aggravated by activity, alleviated by rest

o Often nocturnal pain

o Burning

o Tapping over tarsal tunnel = worsening symptoms (Tinel’s sign)

o Decreased two-point discrimination sensation

Etiology:

o Space occupying lesion in tarsal tunnel

o Ganglion

o Synovial cyst

o Lipoma

o Typically following severe

trauma from scarring or edema

o Severe venous varicosities

o Tenosynovitis

o Tumor within nerve

o Unknown, >50% cases idiopathic

	Above: Contents of the tarsal tunnel

Diagnosis:

o History of tingling pain, burning in posterior tibial nerve distribution distribution

o Positive Tinel’s sign

o Electrodiagnostic studies –

sensory nerve conduction

velocity most sensitive

o +/- MRI to demonstrate

space-occupying lesion

within tarsal tunnel

MRI demonstrating enhancing lesion within tarsal tunnel (arrows)

Treatment:

o Anti-inflammatory medications

o Steroid injection into tarsal tunnel

o Aspiration of cyst or ganglion, recurrence is common

o Immobilization in ankle-foot orthosis

o Surgical release of tarsal tunnel for refractory cases