Neuromodulation for chronic pain.

Neuromodulation is an expanding area of pain medicine that incorporates an array of non-invasive, minimally invasive, and surgical electrical therapies. In this Series paper, we focus on spinal cord stimulation (SCS) therapies discussed within the framework of other invasive, minimally invasive, and non-invasive neuromodulation therapies. These therapies include deep brain and motor cortex stimulation, peripheral nerve stimulation, and the non-invasive treatments of repetitive transcranial magnetic stimulation, transcranial direct current stimulation, and transcutaneous electrical nerve stimulation. SCS methods with electrical variables that differ from traditional SCS have been approved. Although methods devoid of paraesthesias (eg, high frequency) should theoretically allow for placebo-controlled trials, few have been done. There is low-to-moderate quality evidence that SCS is superior to reoperation or conventional medical management for failed back surgery syndrome, and conflicting evidence as to the superiority of traditional SCS over sham stimulation or between different SCS modalities. Peripheral nerve stimulation technologies have also undergone rapid development and become less invasive, including many that are placed percutaneously. There is low-to-moderate quality evidence that peripheral nerve stimulation is effective for neuropathic pain in an extremity, low quality evidence that it is effective for back pain with or without leg pain, and conflicting evidence that it can prevent migraines. In the USA and many areas in Europe, deep brain and motor cortex stimulation are not approved for chronic pain, but are used off-label for refractory cases. Overall, there is mixed evidence supporting brain stimulation, with most sham-controlled trials yielding negative findings. Regarding non-invasive modalities, there is moderate quality evidence that repetitive transcranial magnetic stimulation does not provide meaningful benefit for chronic pain in general, but conflicting evidence regarding pain relief for neuropathic pain and headaches. For transcranial direct current stimulation, there is low-quality evidence supporting its benefit for chronic pain, but conflicting evidence regarding a small treatment effect for neuropathic pain and headaches. For transcutaneous electrical nerve stimulation, there is low-quality evidence that it is superior to sham or no treatment for neuropathic pain, but conflicting evidence for non-neuropathic pain. Future research should focus on better evaluating the short-term and long-term effectiveness of all neuromodulation modalities and whether they decrease health-care use, and on refining selection criteria and treatment variables.

Spinal anesthesia and minimal invasive laminotomy for paddle electrode placement in spinal cord stimulation: technical report and clinical results at long-term followup.

OBJECT: We arranged a mini-invasive surgical approach for implantation of paddle electrodes for SCS under spinal anesthesia obtaining the best paddle electrode placement and minimizing patients' discomfort. We describe our technique supported by neurophysiological intraoperative monitoring and clinical results. METHODS: 16 patients, affected by neuropathic pain underwent the implantation of paddle electrodes for spinal cord stimulation in lateral decubitus under spinal anesthesia. The paddle was introduced after flavectomy and each patient confirmed the correct distribution of paresthesias induced by intraoperative test stimulation. VAS and patients' satisfaction rate were recorded during the followup and compared to preoperative values. RESULTS: No patients reported discomfort during the procedure. In all cases, paresthesias coverage of the total painful region was achieved, allowing the best final electrode positioning. At the last followup (mean 36.7 months), 87.5% of the implanted patients had a good rate of satisfaction with a mean VAS score improvement of 70.5%. CONCLUSIONS: Spinal cord stimulation under spinal anesthesia allows an optimal positioning of the paddle electrodes without any discomfort for patients or neurosurgeons. The best intraoperative positioning allows a better postoperative control of pain, avoiding the risk of blind placements of the paddle or further surgery for their replacement.

Effect of cepea extract-heparin and allantoin mixture on epidural fibrosis in a rat hemilaminectomy model.

AIM: Epidural fibrosis following a laminectomy procedure is a serious problem that results in failed back surgery syndrome. Aserious number of manuscripts have explained its possible mechanism and results but no effective preventive surgical technique or treatment is currently present. MATERIAL AND METHODS: We used a rat hemilaminectomy model at lumbar fourth level. In the treatment group (n:10), the hemilaminectomy sites were filled with cepea extract-allantoin and heparin mixture as sterile cream form. In the second group, the same surgical procedure was performed and the site was filled with physiological saline. All animals were terminated after 6 weeks and laminectomy sites removed en-bloc. Epidural fibrosis was evaluated and compared using semi-quantitative histopathological scoring scales. RESULTS: In the physiological saline group, the fibrosis score was 10.3 points and 90% of the subjects had acute inflammatory reaction, 80% chronic inflammatory reaction and 100% showed bone destruction and reparation process. In the cepea extract group, these values were fibrosis score 4.2 points, 0% acute inflammatory reaction, 33.3% chronic inflammatory reaction and 10% bone destruction and reparation process, respectively. CONCLUSION: This study showed that aloe cepea extract-allantoin and heparin mixture diminished epidural scarring formation effectively with decreased scores of acute and chronic inflammation, compared to the physiological saline solution group.