Neuromodulation : journal of the International Neuromodulation Society
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Objectives. The purpose of this research was to understand the effects of surface functional electrical stimulation (FES) of the tibial nerve on the activation of the gastrocnemius medialis of the stimulated side. Methods. FES was carried out on six healthy subjects, initiated at three different times during gait: early, mid, and late stance. Each stimulation burst consisted of 15 pulses, applied for 300 msec, at 50 Hz stimulation frequency. ⋯ The most prominent effects found in the intervals between the stimulation pulses (interpulse intervals) were found when stimulation was applied early in the stance phase. This study revealed that the only statistically significant effect on burst timing was a delay in offset timing due to mid-timed stimulation. Conclusions. We conclude that additional activation may have been compensated, at least in part, by blocking of the physiological activation during the stimulation burst.
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Background. The treatment of chronic low back and leg pain remains a difficult medical challenge, particularly for patients with postlaminectomy syndrome. While spinal cord stimulation (SCS) has been a significant addition to the available options, it is often inadequate in relieving both the back and leg pain components. We hypothesized that for some patients the combination of SCS with peripheral nerve field stimulation (PNFS) would be a safe, effective alternative that would be more effective than either modality alone. ⋯ Conclusions. Due to the availability of 16 contact capacity generators, neurostimulation with multiple leads in various combinations-including both epidural and peripheral nerve field stimulation simultaneously-can be applied safely and effectively. The availability of this combined approach for a trial of stimulation prior to implant allows patients to compare SCS to PNFS and to indicate a preference for one over the other or for the combination. We conclude that PNFS may be used in combination with SCS as a safe and effective alternative treatment for patients with chronic low back and leg pain, and further suggest that the combined approach should be considered as a treatment option for this population.
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Background. Expert panels of physicians and nonphysicians, all expert in intrathecal (IT) therapies, convened in the years 2000 and 2003 to make recommendations for the rational use of IT analgesics, based on the preclinical and clinical literature known up to those times, presentations of the expert panels, discussions on current practice and standards, and the result of surveys of physicians using IT agents. An expert panel of physicians and nonphysicians has convened in 2007 to update information known regarding IT therapies and to update information on new and novel opioid and nonopioid analgesic compounds that might show promise for IT use. ⋯ Results. The panelists identified several agents that were worthy of future studies for the clinical and rational use of IT agents that are presented in this article. Conclusions. A list of nonopioid IT analgesics, including gabapentin, adenosine, octreotide, the χ-conopeptide, Xen2174, the conopeptide, neurotensis 1 agonist, CGX-1160, the ω-conotoxin, AM-336, and physostigmine, were identified as worthy of future research by the panelists.
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Objectives. This study aims to investigate the effect of functional electrical stimulation (FES) on gait in people with Parkinson's disease. Materials and Methods. Seven subjects with idiopathic Parkinson's disease received single-channel electrical stimulation for eight weeks to the common peroneal nerve to improve heel strike and provide sensory stimulus during the swing phase of gait. Stride length, time, and number of steps to complete a 20-m walk and distance completed in 3 min were assessed. ⋯ An immediate effect of FES was demonstrated over a 3-min walk but not over a 20-m walk. Improvements in gait largely persisted on reassessment four weeks after stopping use of FES although the frequency of falls returned to pretreatment levels. A larger study is required to support these findings, to understand the mechanisms of the effects of electrical stimulation on gait and to identify those most likely to benefit from it.
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Objectives. This study aims to assess tolerability and efficacy of stimulation parameters after vagus nerve stimulator (VNS) pulse generator replacement. Materials and Methods. We carried out an observational, retrospective study, reviewing our experience with VNS generator replacements in 28 epilepsy patients. Results. Seven patients had actual end of battery life (EOBL) (with symptoms), and 21 patients had asymptomatic projected EOBL. ⋯ Failure to return to baseline current was not related to previous VNS duration, same- vs. different-battery generator replacements, or antiepileptic medication changes. Conclusions. After VNS generator replacement, patients' common inability to tolerate preoperative current settings does not lead to more seizures. A chronic modification of the vagus nerve system's sensitivity to stimulation changes may be hypothesized.