OP0099 EFFECTIVENESS OF REPETITIVE TRANSCRANIAL MAGNETIC STIMULATION IN PATIENTS WITH FAILED BACK SURGERY SYNDROME

Abstract

Background Failed back surgery syndrome (FBSS) is the term of persistent back and/or leg pain after lumbar surgery (1). Repetitive transcranial magnetic stimulation (r-TMS) is a technique that allows non-invasive and relatively painless stimulation of cerebral cortex. It can reduce the experience of chronic pain by using magnetic field to produce small electrical currents in the cortex (2). Objectives The aim of this study is to determine the effectiveness of r-TMS treatment on patients with FBSS. Methods In this double-blinded, randomized, placebo-controlled trial, 20 patients (aged 34-65 years) clinically diagnosed as FBSS, who had a history of surgery for lumbar disk herniation with persistent back and leg pain. Only patients with no root compression in postoperative magnetic resonance imaging of lumbar spine were included. Patients were randomly assigned to r-TMS (n:10) and sham (n:10) groups. Patients in r-TMS group received 5 Hz of r-TMS, as a 20-min (1000 pulses) daily session, 5 days per weeks, for a total of 10 sessions. R-TMS applied with MagVenture device (MagPro X100, Denmark, 2009) and figure eight coil (MMC 140 parabolic, MagVenture). Control group received sham r-TMS with the same protocol. Patients were assessed before and after the 1st and 5th sessions, at the end of the treatment and at 2 weeks, 1 month and 3 months after treatment. Visual Analogue Scale (VAS), DN-4, Oswestry Disability Index (ODI), Beck Depression Inventory (BDI), Pittsburgh Sleep Quality Index (PSQI) were used for evaluation. Results There were no statistically significant differences between the groups for age, sex, number of surgery, pain duration, working status and drug usage. Significant improvements were achieved in DN4, ODI, BDI and PSQI scores in r-TMS group in comparison to sham group. Both groups displayed improvements in VAS scores while improvement in the sham group was limited to first month. Achieved improvements in r-TMS group in terms of VAS, DN4, ODI, BDI and PSQI scores were sustained at third month. Conclusion Repetitive transcranial magnetic stimulation might be an effective treatment alternative in patients with FBSS, further studies with larger groups are needed.