Intraoperative Nerve Monitoring for Tarsal Tunnel Decompression: A Surgical Technique to Improve Outcomes

J Foot Ankle Surg. 2019 Nov;58(6):1203-1209. doi: 10.1053/j.jfas.2019.04.009.

Abstract

The aim of the current study was to evaluate the effectiveness of intraoperative neuromonitoring (INM) as an adjunct in performing tarsal tunnel decompression surgery. We reviewed 38 patients who met inclusion criteria. INM was used to measure the voltage of the abductor hallucis and digiti quinti muscles both before and after decompression. Observed changes intraoperatively were acute and within minutes of the decompression performed by the surgeon. Patient outcomes were ascertained from clinical findings and classified as excellent, fair, or poor. Patient outcomes and the voltage change were measured and assessed for association, and statistically significant differences were found between outcome groups. Of the 38 patients, 29 (76%) had excellent outcomes, with a mean change in microvolts of 2088.28 ± 1172.44 (684%) (p = .0004) and 2173.24 ± 1228.39 (742%) (p = .0014) for abductor hallucis and abductor digiti quinti, respectively. The study supports INM as a useful adjunct in performing tarsal tunnel decompression.

Keywords: abductor digiti quinti; abductor hallucis; electromyography; lower extremity nerve decompression; nerve integrity monitoring; posterior tibial nerve; tarsal tunnel syndrome.

MeSH terms

  • Cohort Studies
  • Decompression, Surgical*
  • Electromyography
  • Female
  • Humans
  • Intraoperative Neurophysiological Monitoring*
  • Male
  • Middle Aged
  • Muscle, Skeletal / innervation*
  • Patient Outcome Assessment
  • Retrospective Studies
  • Tarsal Tunnel Syndrome / surgery*