Spinal Cord Stimulation (SCS) has been a well-established treatment for chronic neuropathic pain for decades. One of the most general indication for SCS is Failed Back Surgery Syndrome with associated legs and/or low back pain.~Conventional low frequency neurostimulation is applied with a tonic wave shape (pulse width is usually 300 to 500 μsec, amplitude 2 to 5 mA, and frequency 40 to 50 Hz); this kind of stimulation produces a perceptible paraesthesias in the area of stimulation covering the region of pain. Further development in waves of stimulation during the recent years led to new paradigms of sub-perception stimulation like Burst stimulation that has characteristics of a cluster of waves with higher frequency.~The efficacy of these two wave forms has been demonstrated by different authors. Both Tonic and Burst stimulation offer neuropathic pain suppression, with slightly superiority of the Burst wave for the FBSS.~Recent advances in technology of the implantable devices for spinal cord stimulation led to the possibility to combine the two stimulation waves described allowing the design of a possible new paradigm of stimulation. The Tonic and Burst wave can be combined to stimulate the same pain area using the same configuration otherwise they can be programmed to stimulate two different pain areas with two different configurations. Both burst and tonic waveforms paradigms can be customized according to patients' need. The characteristics of this combined stimulation wave in terms of efficacy, non inferiority, energy consumption, and patient satisfaction are unknown.~The primary objective of this trial is to compare pain suppressive effect of Low Frequency Tonic Wave versus Low Frequency Combined Burst and Tonic Wave for Spinal Cord Stimulation in subjects with refractory neuropathic leg and low back pain as result of FBSS.~Patients fulfilling the inclusion criteria will be enrolled in the study and receive electrocatheter implant. Then, they will be observed for a two-weeks trial period in which the efficacy of the stimulation and the compliance of the patient is evaluated. During this trial a Tonic wave stimulation is administered by the external generator. After this trial, the definitive generator will be implanted. Two weeks of Tonic stimulation will follow the surgery to avoid any interference of the pain measurement with the surgical pain. After this two weeks period, the stimulation will be switched into the combined waveform for 15 days. At the end of the study period, the final waveform setting of the SCS will be in accord with the patient's stimulation preference.
Spinal Cord Stimulation (SCS) has been a well-established treatment for chronic neuropathic pain in Failed Back Surgery Syndrome with associated legs and/or low back pain. The waves used in Spinal Cord Stimulation are mainly Tonic or Burst. Both Tonic and Burst stimulation offer neuropathic pain suppression, with slightly superiority of the Burst wave for the FBSS. The aim of our study is to evaluate the efficacy of a new stimulation paradigm with the combination of the two wave forms.