Tarsal Tunnel Syndrome: Analysis for Characteristics of MRI and Nerve Conduction Study, and the Outcome of Decompression Surgery

Abstract

Objective: In this retrospective study, the authors aimed to reveal radiological, electrophysiological characteristics of tarsal tunnel syndrome (TTS), and their usefulness for diagnosis and measuring the treatment outcome. In addition, we assess postoperative outcomes by clinical and electrophysiological tools. Method: Thirty-three patients underwent unilateral tarsal tunnel decompression. Ankle MRI and nerve conduction study was performed in all patients. Preoperative symptoms, radiological and electrophysiological results were reviewed and follow-up statuses were evaluated. Results: Twenty-eight of 33 (84.8%) patients showed symptomatic recovery and 23 (69.7%) showed improvement objectively in the nerve conduction study. Preoperative MRI revealed a specific anatomical lesion in 18 patients. Improvements in nerve conduction study parameters were observed mainly in conduction velocity of lateral plantar nerves. There was no significant clinical factor to predict postoperative outcome. Conclusion: In the present study, postoperative outcomes from the clinical and electrophysiological perspectives were satisfactory. Nerve conduction study was good to evaluate the disease status and measure the surgical outcome objectively. MRI provided supportive information for diagnosing TTS. Tarsal tunnel decompression is warranted in those patients who remain symptomatic despite prolonged conservative treatment.