Electrical safety in spinal cord stimulation: current density analysis by computer modeling

The possibility of tissue damage in spinal cord stimulation was investigated in a computer modeling study. A decrease of the electrode area in monopolar stimulation resulted in an increase of the current density at the electrode surface. When comparing the modeling results with experimental data from literature, it was concluded that even with a small electrode area (0.7 mm2) tissue damage in spinal cord stimulation is improbabl

Complex regional pain syndrome of the foot and its management using spinal cord stimulation

Background: This article discusses neuropathic foot pain with particular reference to complex regional pain syndrome. It provides recommendations for the clinical evaluation of complex regional pain syndrome and highlights the value of spinal cord stimulation in its management. The aim is to review neuropathic foot pain in complex regional pain syndrome and outline its management using spinal cord stimulation. It is important for Podiatrists managing such patients to have an understanding of this treatment modality. Methods: A narrative literature review was undertaken using English language medical databases combining search strategies for complex regional pain syndrome and spinal cord stimulation. Results: Spinal cord stimulation improves the subjective symptoms of the neuropathic foot pain of complex regional pain syndrome, enables objective functional improvement and reduces analgesic consumption. Conclusion: Recent technical developments in spinal cord stimulation have led to improved stimulation patterns adapted to the patients’ needs. Careful preoperative diagnosis, robust patient selection and frequent follow-up are vital for the success of this method

Burst Spinal Cord Stimulation in a Rat Model of Chronic Neuropathic pain:Spinal and Supraspinal Mechanisms

The results of this thesis show that there is a complex relationship between the analgesic effect and the parameters of burst spinal cord stimulation. Preclinical behavioural tests have shown that a delayed wash-in of the analgesic effect occurs in burst spinal cord stimulation compared to tonic spinal cord stimulation. In addition, in a renowned animal model for chronic neuropathic pain, it was demonstrated that Gamma-amino butyric acid (GABA)-ergic mechanisms underlie the analgesic effect of both burst spinal cord stimulation and tonic spinal cord stimulation. Using an innovative new behavioural test in combination with functional Magnetic Resonance Imaging (MRI) research, we demonstrated that both burst spinal cord stimulation and tonic spinal cord stimulation induce increased brain activity in brain regions involved in processing cognitive-emotional aspects of pain. However, for burst spinal cord stimulation, the relevant activity was more intense and widespread. In summary, burst spinal cord stimulation has similarities as well as differences with tonic spinal cord stimulation. It is important that the differences will be further investigated in the future in order to optimally utilize the analgesic effectiveness of burst spinal cord stimulation

Use of spinal cord stimulation in managing neuropathic foot pain: an observational pilot case series study

Objective: In cases of complex regional pain syndrome where conservative treatment is unsuccessful in controlling neuropathic foot pain spinal cord stimulation may be considered. To our knowledge there have been no such cases reported in the foot & ankle literature. The aim of the study was to establish useful information that may supplement our understanding of this complex multifactorial problem and help toinform future management of similar cases. Methods: A pilot observational case series study was undertaken to investigate the use of spinal cord stimulation in the management of neuropathic foot pain using five cases with complex regional pain syndrome (type I). Results: Reduced pain following spinal cord stimulation was reported. The interval between diagnosis and commencement of spinal cord stimulation was variable between cases and maybe responsible for differing levels and timing of pain relief experienced. Conclusion: Careful preoperative diagnosis, robust patient selection and close postoperative monitoring are vital for a successful outcome. The small sample size and potential for bias, limit the generalizability to a larger population. A larger study is therefore indicated to expand upon preliminary findings

Spinal Cord Stimulation for Refractory Angina Pectoris -A Case Report-

Refractory angina pectoris is defined as angina refractory to optimal medical treatment and standard coronary revascularization procedures. Despite recent therapeutic advances, patients with refractory angina pectoris are not adequately treated. Spinal cord stimulation is a minimally invasive and reversible technique which utilizes electrical neuromodulation by means of an electrode implanted in the epidural space. It has been reported to be an effective and safe treatment for refractory angina pectoris. We report a case of spinal cord stimulation which has effectively relieved chest pain due to coronary artery disease in a 40-year-old man. This is the first report of spinal cord stimulation for treatment of refractory angina pectoris in South Korea

A Call to Action toward Optimizing the Electrical Dose Received by Neural Targets in Spinal Cord Stimulation Therapy for Neuropathic Pain

Spinal cord stimulation has seen unprecedented growth in new technology in the 50 years since the first subdural implant. As we continue to grow our understanding of spinal cord stimulation and relevant mechanisms of action, novel questions arise as to electrical dosing optimization. Programming adjustment — dose titration — is often a process of trial and error that can be time-consuming and frustrating for both patient and clinician. In this report, we review the current preclinical and clinical knowledge base in order to provide insights that may be helpful in developing more rational approaches to spinal cord stimulation dosing. We also provide key conclusions that may help in directing future research into electrical dosing, given the advent of newer waveforms outside traditional programming parameters

Spinal cord stimulation for predominant low back pain in failed back surgery syndrome: study protocol for an international multicenter randomized controlled trial (PROMISE study)

Background: Although results of case series support the use of spinal cord stimulation in failed back surgery syndrome patients with predominant low back pain, no confirmatory randomized controlled trial has been undertaken in this patient group to date. PROMISE is a multicenter, prospective, randomized, open-label, parallel-group study designed to compare the clinical effectiveness of spinal cord stimulation plus optimal medical management with optimal medical management alone in patients with failed back surgery syndrome and predominant low back pain. Method/Design: Patients will be recruited in approximately 30 centers across Canada, Europe, and the United States. Eligible patients with low back pain exceeding leg pain and an average Numeric Pain Rating Scale score >= 5 for low back pain will be randomized 1:1 to spinal cord stimulation plus optimal medical management or to optimal medical management alone. The investigators will tailor individual optimal medical management treatment plans to their patients. Excluded from study treatments are intrathecal drug delivery, peripheral nerve stimulation, back surgery related to the original back pain complaint, and experimental therapies. Patients randomized to the spinal cord stimulation group will undergo trial stimulation, and if they achieve adequate low back pain relief a neurostimulation system using the Specify (R) 5-6-5 multi-column lead (Medtronic Inc., Minneapolis, MN, USA) will be implanted to capture low back pain preferentially in these patients. Outcome assessment will occur at baseline (pre-randomization) and at 1, 3, 6, 9, 12, 18, and 24 months post randomization. After the 6-month visit, patients can change treatment to that received by the other randomized group. The primary outcome is the proportion of patients with >= 50% reduction in low back pain at the 6-month visit. Additional outcomes include changes in low back and leg pain, functional disability, health-related quality of life, return to work, healthcare utilization including medication usage, and patient satisfaction. Data on adverse events will be collected. The primary analysis will follow the intention-to-treat principle. Healthcare use data will be used to assess costs and long-term cost-effectiveness. Discussion: Recruitment began in January 2013 and will continue until 2016

Spinal cord stimulation in chronic pain: evidence and theory for mechanisms of action.

Well-established in the field of bioelectronic medicine, Spinal Cord Stimulation (SCS) offers an implantable, non-pharmacologic treatment for patients with intractable chronic pain conditions. Chronic pain is a widely heterogenous syndrome with regard to both pathophysiology and the resultant phenotype. Despite advances in our understanding of SCS-mediated antinociception, there still exists limited evidence clarifying the pathways recruited when patterned electric pulses are applied to the epidural space. The rapid clinical implementation of novel SCS methods including burst, high frequency and dorsal root ganglion SCS has provided the clinician with multiple options to treat refractory chronic pain. While compelling evidence for safety and efficacy exists in support of these novel paradigms, our understanding of their mechanisms of action (MOA) dramatically lags behind clinical data. In this review, we reconstruct the available basic science and clinical literature that offers support for mechanisms of both paresthesia spinal cord stimulation (P-SCS) and paresthesia-free spinal cord stimulation (PF-SCS). While P-SCS has been heavily examined since its inception, PF-SCS paradigms have recently been clinically approved with the support of limited preclinical research. Thus, wide knowledge gaps exist between their clinical efficacy and MOA. To close this gap, many rich investigative avenues for both P-SCS and PF-SCS are underway, which will further open the door for paradigm optimization, adjunctive therapies and new indications for SCS. As our understanding of these mechanisms evolves, clinicians will be empowered with the possibility of improving patient care using SCS to selectively target specific pathophysiological processes in chronic pain

Spinal cord stimulation in failed back surgery

Objective: Spinal cord stimulation is used for treating failed back surgery syndrome, chronic arachnoiditis, peripheral neuropathies, postamputation phantom pain, complex regional pain syndrome and pain secondary to spinal cord injury. In this study we present 7 cases with intractable neuropathic radicular pain which developed following spine surgery. Material and Methods: Spinal cord stimulation was applied to 7 (3male/4 female) patients who had failed back surgery syndrome and pain resistant to medical and invasive methods, with the council decision, which included neurosurgery, neurology, and psychiatry. One week stimulation trial was applied to all cases. Results:The mean age of the patients was 54.85±7.64 years. The mean of pain intensity in Visual Analog Scale was 8.71±0.74 at preoperative status and post operative pain intensity was 2.27±0.67 at 6 months. Pain intensity significantly decreases after spinal cord stimulation (p=0.000). One of the three cases who had unsuccessful trial period received morphine pump implantation, and percutaneous lumbar sympathectomy was applied to another one. One case who received permanent implantation was replaced to another location due to skin erosion. There was no morbidity. Conclusion: Spinal cord stimulation is an effective tool in reducing pain, in patients who have unsuccessful lower back surgery with the correct indications