Efficacy of a single botulinum toxin A injection for distal tarsal tunnel syndrome: A protocol for a randomized, double-blinded trial

INTRODUCTION: Distal tarsal tunnel syndrome (DTTS) is characterised by compression of the tibial nerve as it passes underneath the abductor hallucis muscle belly. There is no current consensus on treatment for DTTS. This study was conducted to compare and evaluate the effect of ultrasound-guided botulinum toxin A (BTX-A) versus ultrasound-guided corticosteroid injection (CSI) for the treatment of DTTS. METHODS: This study was a single-centre, randomized, and double-blinded trial. The study protocol was submitted to the local ethics committee board and subsequently registered in a research registry. 88 patients with DTTS were randomly divided into 2 groups according to the treatment received. The patients were evaluated over 12 weeks. Evaluation was via the Foot Health Status Questionnaire (FHSQ). The primary outcome measures were pain and the secondary outcomes were function and the use of oral analgesics. All of the assessments were performed at baseline and at 3, 6, and 12 weeks after treatment. RESULTS: This is a randomized controlled trial evaluating the efficacy of BTX-A versus CSI in the treatment of DTTS. This study has limited inclusion and exclusion criteria and a well-controlled intervention. CONCLUSIONS: The results of this trial will provide more evidence on which method can better treat DTTS. TRIAL REGISTRATION: We have registered this trial with the Australian New Zealand Clinical Trials Registry and the temporary trial number is 380,105.