RESUMO
BACKGROUND: We report the results from the first large, postmarket, multicentre, randomised controlled trial (RCT) evaluating peripheral nerve stimulation (PNS) for the treatment of chronic peripheral pain with a micro-implantable pulse generator (micro-IPG). METHODS: Subjects meeting eligibility were randomised (2:1) to either the active arm receiving PNS and conventional medical management (CMM) or the control arm receiving CMM alone. Treatments were limited to the following areas: lower back, shoulder, knee and foot/ankle. RESULTS: At 6 months, the active arm achieved an 88% responder rate with a 70% average reduction in pain. At the 3-month primary endpoint, the active arm achieved an 84% responder rate with an average pain reduction of 67% compared with the control arm, which achieved a 3% responder rate with an average pain reduction of 6%. Both responder rate and pain reduction in the active arm were significantly better than in the control arm (p<0.001). A majority of patient-reported outcomes also reached statistical significance. There have been no reports of pocket pain and no serious adverse device effects. 81% of subjects found the external wearable component of the PNS system to be comfortable. CONCLUSIONS: This study successfully reached its primary endpoint-the active arm achieved a statistically significant superior responder rate as compared with the control arm at 3 months. These RCT results demonstrated that PNS, with this micro-IPG, is efficacious and safe. This ongoing study will follow subjects for 3 years, the results of which will be reported as they become available.
RESUMO
The aims of this study were two-fold: first, to simplify the method for creating a recently described neuropathic pain model in the rat, and second, to evaluate the effects of a number of drugs with analgesic or antihyperalgesic properties, in this model. Continuous intravenous vincristine infusion (1-100 microg kg(-1) day (-1)) for 14 days resulted in a dose dependent tactile allodynia (as measured by von Frey filaments) by 7 days at doses between 30 - 100 microg kg(-1) day (-1), with a hindlimb motor deficit observed at doses greater than 50 microg kg(-1) day (-1). No thermal hyperalgesia was observed. Systemic morphine, lidocaine, mexiletine and pregabalin (given intraperitoneally) produced significant reduction of the allodynia, while tetrodotoxin was without effect. Continuous intravenous infusion of vincristine in rats thus provides a reliable model of chemotherapy induced neuropathy which may be used in defining the mechanism and pharmacology of this clinically relevant condition.
