Masashi Kumon, Toshikazu Tani, Masahiko Ikeuchi, Kazunobu Kida , Ryuichi Takemasa , Noritsuna Nakajima , Katsuhito Kiyasu , Nobuaki Tadokoro, Shinichiro Taniguchi
Orthopaedic surgery, Kochi Medical School, 783-8505 Nankoku, Japan. E-mail: mk480158@gmail.com
DOI: 10.2340/16501977-1875

Objectives: To determine whether repetitive tibial nerve stimulation (RTNS) affects neurogenic claudication and F-wave conduction in lumbar spinal stenosis.
Design: An intervention study: before/after trial.
Subjects: Data for 12 central lumbar spinal stenosis patients were compared with 13 age- and sex-matched healthy volunteers.
Methods: A conditioning RTNS at the ankle, 0. 3-ms duration square-wave pulses with an intensity 20% higher than the motor threshold, was applied at a rate of 5/s for 5 min. We assessed the effects of RTNS on the claudication distance at which the lumbar spinal stenosis patients can no longer continue walking due to increasing leg symptoms, and on tibial F-wave measurements.
Results: A comparison between mean pre-RTNS and post-RTNS revealed a significant difference in claudication distance (66 m (standard deviation (SD) 19) vs 133 m (SD 37); p = 0. 003), mean F-wave minimal latency (48. 3 ms (SD 1. 7) vs 44. 8 ms (SD 1. 0); p = 0. 007) and mean F-wave conduction velocity (53. 3 m/s (SD 2. 0) vs 55. 5 m/s (SD 1. 9); p = 0. 009) in the lumbar spinal stenosis group, but not in the control group.
Conclusion: RTNS has beneficial effects on neurogenic claudication and F-wave conduction in central lumbar spinal stenosis patients. This phenomenon may have practical value in providing a new therapeutic modality for lumbar spinal stenosis.