Role of ultrasound in posteromedial tarsal tunnel syndrome: 81 cases

Abstract

Posteromedial tarsal tunnel syndrome is a disorder affecting the tibial nerve or its branches. Diagnosis is established on the basis of physical examination and can be confirmed by electrophysiological evidence. However, diagnostic imaging is always required to identify the possible site of compression. High-resolution ultrasound (US) is playing an increasingly important role in the study of the nerves thanks to a series of advantages over magnetic resonance imaging, such as lower costs and widespread availability, high spatial resolution, fast examination using axial scans, dynamic and comparative studies, possibility of carrying out a study with the patient in the standing position, US Tinel sign finding, and the contribution of color/power Doppler US. We present the results obtained in a series of 81 patients who underwent US imaging between 2008 and 2013 due to posteromedial tarsal tunnel syndrome. Keywords Tarsal tunnel Á Tibial nerve Á UltrasoundRiassunto La sindrome del tunnel tarsale posterioremediale è una sofferenza del nervo tibiale o di un suo ramo. La diagnosi è clinica e può essere confermata dall'elettrofisiologia, ma un'indagine con imaging è sempre necessaria per trovare l'elemento di compressione. L'ecografia ad alta risoluzione sta giocando un ruolo sempre più importante per lo studio dei nervi, per i diversi vantaggi rispetto alla risonanza magnetica: costo e disponibilità, risoluzione spaziale, esplorazione rapida mediante tecnica di scansione assiale, dinamica e comparativa, possibilità di uno studio con paziente in piedi, segno di Tinel ecografico, contributo del Doppler.

Nerve ultrasound in electrophysiologically verified tarsal tunnel syndrome

“…The high detection rate for identifying both underlying nerve enlargement and its etiology is in keeping with what is reported. 1,4,12,20,21 The high shear forces generated across the foot and the talo-tarsal region likely explain why tibial nerve damage at the ankle has a high rate of perineural structural abnormality in comparison with the low rates seen in the hand in carpal tunnel syndrome. 22 One group reported their experience with imaging (both ultrasound and MRI) in TTS and suggested that the tibial nerve was mostly of normal size despite obvious nerve compression.…”

“…Studies have suggested that up to 80% of TTS have a specific identifiable cause. 12 We set out to test the role of nerve ultrasound (NUS) in TTS at our hospital.…”

Ultraschall peripherer Gelenke und des Achsenskeletts

“…Das Tarsaltunnelsyndrom ist das häufigste Kompressionssyndrom der unteren Extremität, jedoch deutlich seltener als das Karpal-und Kubitaltunnelsyndrom. Je nachdem welcher Nervenast komprimiert wird, klagen die Patienten über brennende Schmerzen an der Ferse oder der Fußsohle, sogar Schmerzen an den Zehen werden nicht selten beschrieben [68]. Ursächlich für die Kompression des N. tibialis bzw.…”

“…der Nn. plantares sind häufig Gefäßanomalien, Gan-glien, Fehlstatik oder entzündliche Prozesse verantwortlich [68]. Normwerte für den N. tibialis im Tarsaltunnel sind bisher nicht publiziert worden, weswegen der Vergleich mit der gesunden Gegenseite obligatorisch ist.…”

Reply

“…Tarsal tunnel syndrome (TTS) also causes symptoms similar to plantar fasciitis, and when suspected, electrodiagnostic tests of the tibial nerve and US of the medial ankle should be performed . US for diagnosis of TTS has been performed to investigate a soft‐tissue mass or space‐occupying lesion, such as a ganglion, that compress the tibial or plantar nerves as well as the nerve lesion, as shown by Coraci et al…”