Clinical and functional outcome after alcohol neurolysis of the tibial nerve for ankle–foot spasticity

PURPOSE: To report one's experience of using 50-100% alcohol for neurolysis of the tibial nerve in chronic ankle-foot spasticity. METHODS: The records of patients who received alcohol neurolysis of the tibial nerve were retrospectively reviewed. Repetitive monopolar nerve stimulation was used to localize the tibial nerve. Outcome measures included muscle tone as measured by the Modified Ashworth Score (MAS), passive ankle range of motion (PROM), effect on clonus, plantar flexor motor strength, visual gait analysis and use of orthoses. RESULTS: A total of 21 tibial nerves were neurolysed in 18 patients (mean age 38.9 +/- 15.8 years, 12 males, six females). Mean duration post-event was 14.8 +/- 3.9 months. The mean pre-neurolysis MAS was 2.50 +/- 0.77 and this improved to 0.97 +/- 0.88 (p < 0.001) and 0.93 +/- 0.85 (p < 0.001) at 1 and 6 months post-procedure, respectively. Average duration of effect was 10.5 +/- 8.9 months. Eleven out of 12 patients (91.7%) with sustained ankle clonus had complete abolishment lasting 6 months. Mean gain in PROM was 24.6 +/- 16.1 degrees and 32.6 +/- 19.0 degrees at 1 and 3 months post-neurolysis, respectively (p < 0.001, < 0.02). No decrease in motor strength was seen post-neurolysis. All 13 ambulant patients had visible improvements in gait. Complications were transient and included dysesthetic pain (4), sensory loss (1) and distal limb oedema (1). CONCLUSION: Alcohol neurolysis (50-100%) of the tibial nerves is an effective and safe method of managing ankle-foot spasticity.