Spinal Cord Stimulation In Patients Research Articles

Prospective, Randomized Blind Effect-on-Outcome Study of Conventional vs High-Frequency Spinal Cord Stimulation in Patients with Pain and Disability Due to Failed Back Surgery Syndrome.

Spinal cord stimulation (SCS) for patients with failed back surgery syndrome (FBSS) show variable results and limited to moderate evidence. In the last years the stimulation of high frequency (HF) has been considered as a better alternative in this pathology for its supposed benefits compared to the stimulation with conventional frequency (CF). To compare in one year follow-up, the efficacy of high-frequency SCS (HF) versus conventional frequency SCS (CF) on the patients with FBSS. Prospective, Randomized blind trial. Academic University Pain Medicine Center. Seventy eight patients with FBSS diagnosis based on internationally recognized criteria, and refractory to conservative therapy for at least 6 months, have been initially recruited, and. Sixty subjects met the eligibility criteria and were randomized and scheduled for the trial phase.The patients were randomly assigned in either, one of the two groups: CF SCS or HF SCS. Within the study methods, special attention was paid to standardizing patient programming, so that these parameters would not impact the results.The trial period was considered successful if there was ?50% reduction in the NRS from baseline. A total of 55 subjects successfully completed all assessments during one year follow-up. Change patterns in scores do not differ based on high versus conventional frequency, with significant global average reduction at 1 year similarly for both groups. Among all the items included in the Short Form-12 questionnaire (SF-12), only the variations in the social function score between the instants t1 and t2 are somewhat higher in the high frequency group. The evolutionary pattern of the different parameters studied in our patients with FBSS does not differ according to their treatment by spinal stimulation, with conventional or high frequency, in one year follow-up.

Influence of inter-stimulus interval of spinal cord stimulation in patients with disorders of consciousness: A preliminary functional near-infrared spectroscopy study.

Spinal cord stimulation (SCS) is a promising treatment for disorders of consciousness (DOC), but the underlying mechanism and most effective procedures remain uncertain. To optimize the protocol, previous studies evaluated the frequency-specific effects of SCS on neurophysiological activities. However, whether and how the inter-stimulus interval (ISI) parameter affects the SCS neuromodulation in DOC remains unknown. We enrolled nine DOC patients who had implanted SCS devices and conducted three different durations of ISIs. Using functional near-infrared spectroscopy (fNIRS), we monitored the blood volume fluctuations in the prefrontal and occipital cortices during the SCS. The results showed that short stimuli (30 s) induced significant cerebral blood volume changes, especially in the prefrontal cortex, an important area in the consciousness system. By comparing the mean value of the responses from the first and the last block in each session, a shorter ISI was found to improve the blood volume in the prefrontal cortex. This phenomenon was more significant for the subgroup of patients with a favorable prognosis. These preliminary results imply that the ISI may be an important factor for SCS. The research paradigm proposed here also provides insights for further quantitative evaluations of the therapeutic effects of neuromodulation.

Spinal cord stimulation in treatment of patients with critical lower limb ischemia

Critical limb ischemia (CLI) is a state of substantial reduction of blood flow in the extremities, mostly due to severe obstruction of the arteries. In lower limbs, it produces severe pain after even a short distance walk (intermittent claudication) and/or skin ulcers or sores. Surgical revascularization is a “golden standard” in CLI therapy, but it is contraindicated or not accessible for a large proportion of patients, while the medical prognosis is poor for conservative therapy. This situation stimulated the development of alternative approaches, including spinal cord stimulation (SCS) and various methods of “indirect” revascularization. In this paper, the authors give a short description of the latest approaches and a detailed review of the SCS method, while paying special attention to the studies that demonstrate not only a palliative effect of SCS (pain reduction), but also clinically significant changes in the indicators of lower limb muscles blood supply. CLI is characterized with a "vicious circle": pain causes reduced mobility and changes in the preferred limb position, which in turn lead to edema triggering an increase of ischemia and further elevation of pain. The clinical effects of SCS in CLI patients are related both with pain relief leading to a break of this vicious circle, and with the direct vasodilatory effects of the stimulation itself. There are several possible biological mechanisms of these actions, but most probably the therapeutic actions of SCS arise from their combination. Examination of different opinions about the appropriateness of spinal cord stimulation in patients with CLI, including those related to the economic efficiency of the method, leads to the conclusion that the evidence on these issues is currently insufficient. The reviewed data demonstrate the need for further development of the CLI treatment methods and high urgency of this problem.Received 6 April 2017. Accepted 23 April 2017.Funding: The study did not have sponsorship.Conflict of interest: The authors declare no conflict of interest.

Preferred frequencies and waveforms for spinal cord stimulation in patients with complex regional pain syndrome: A multicentre, double-blind, randomized and placebo-controlled crossover trial.

Conventional tonic spinal cord stimulation (SCS) is an effective treatment for patients with therapy-resistant complex regional pain syndrome (CRPS). Although the therapeutic effect of SCS can diminish over time due to tolerance, pain control can be regained by changing the pulse width and the amplitude and/or by increasing the stimulation frequency. This multicentre, double-blind, randomized and placebo-controlled crossover trial was conducted to investigate whether more effective pain reduction is achieved with different frequencies (trial registration, current controlled trials, ISRCTN 36655259). The investigated settings are as follows: standard 40, 500, 1200Hz, burst and placebo stimulation. All five were programmed in random order during the 10-week crossover period (2 weeks/setting). The primary outcome parameters were scores on the visual analogue scale (VAS), McGill Pain Questionnaire (MPQ) and the Global Perceived Effect (GPE); at the end of the crossover period, patients decided which SCS setting they preferred. A linear mixed models analysis was performed in 29 patients who completed the crossover trial. Significant pain reduction and GPE satisfaction was achieved with four SCS settings compared with placebo stimulation, and these four settings did not differ significantly from each other. Standard stimulation was preferred by 48% of the patients, while 52% preferred non-standard stimulation. Other than pain reduction, factors such as user-friendliness, comfort and recharging time may have influenced the patient's final decision for the preferred stimulation setting. Apparently, for various reasons, patients have a preference for different SCS setting. Therefore, future neuromodulation should aim to implement customized individual patient care by incorporating all stimulation options in one device. This study demonstrates that standard frequency SCS is an effective therapy for patients with CRPS. However, it also demonstrates that patients can often gain better pain reduction with non-standard frequencies of SCS. Furthermore, it shows that the preferred stimulation setting is not solely driven by the amount of pain reduction, but is also influenced by which stimulation setting feels most comfortable and provides the best user-friendliness. Therefore, we strive to maximize the therapeutic effects of SCS in as many patients as possible. This can be achieved with customized individual patient care by incorporating the various frequencies and waveforms into one single device.

Intraoperative electrophysiological monitoring for C1-2 spinal cord stimulation.

OBJECTIVE This study is a retrospective case series involving C1-2 spinal cord stimulation in patients with complex regional pain syndrome (CRPS) under general endotracheal anesthesia. Currently, C1-2 paddle lead placement is an accepted practice, which provides effective cervical stimulation to ameliorate upper-extremity and sometimes lower-extremity symptoms experienced by patients with CRPS. However, this technique must be performed under general endotracheal anesthesia rather than in an awake or semiconscious state due to intraoperative safety concerns and patient comfort. The authors aim to provide additional data to support the following novel technique: the use of somatosensory evoked potential (SSEP) diminution data to assist with proper midline placement of C1-2 leads under general anesthesia. METHODS SSEP median nerve (MN) and posterior tibial nerve (PTN) data were collected from 6 patients undergoing placement of C1-2 leads under general anesthesia. Fluoroscopy was used as an initial guide for proper anatomical midline placement. This was followed by the activation of the spinal cord stimulator and simultaneous collection of primarily MN SSEPs as well as PTN SSEPs for physiological midline placement. Unilateral and bilateral reductions in SSEPs assisted with the correct lateralization of the lead to ensure effective postoperative coverage according to the patient's individual preoperative symptoms. RESULTS Six patients were monitored using SSEPs and repeatable, reliable MN and PTN baseline responses were obtained from all. A reduction in amplitude ranging from 5% to 87% was observed, confirming inhibition of dorsal column conduction, and an average pain relief of 63% at short-term and 64% at long-term follow-up was recorded with 6 of 6 and 5 of 6 patients responding, respectively. CONCLUSIONS Intraoperative SSEP collision study testing appears to be a safe technique to monitor placement of C1-2 paddle leads intraoperatively under general anesthesia.

Spinal cord stimulation for FBSS and CRPS: A review of 80 cases with on-table trial of stimulation.

Spinal cord stimulation (SCS) is used for the treatment of chronic neuropathic pain, a notoriously difficult condition to treat. Failed Back Surgery Syndrome (FBSS) and Complex Regional Pain syndrome (CRPS) remain the strongest indications. Funding remains a difficult issue and the use of trial of stimulation is the traditional method of ensuring best outcomes from implantation. A retrospective and consecutive review of 80 cases of spinal cord stimulation for patients with a diagnosis of FBSS and CRPS having undergone prior comprehensive medical management and interventional treatment with no sustained benefit. Trial of stimulation was performed on-table and if acceptable coverage was achieved, the case proceeded to full implantation. The mean patient age was 50.08 years (range 28-80 years). At 12 months follow-up, thirty two patients (40%) no longer required analgesic medication. Thirty patients (37.5%) reported their pain was manageable with first line analgesics. Fourteen (17.5%) reported their pain was manageable first line analgesic and occasional tramadol or codeine. Four (5%) reported that their pain was manageable with NSAID's, paracetamol, amitriptyline, and regular codeine or tramadol. Seventeen out of eighty patients (21.25%) were unemployed before SCS implant, and at 12 months follow up eight of these patients (47.05%) had returned to work. There was no infective complications or explants. Two patients (2.53%) required one lead revision, which was successful. SCS is the most effective treatment for FBSS and CRPS, which is proven resistant to medical management. On-table trial and implantation is easy to perform with good success rate and low morbidity and if successful will reduce complication rates, especially infection.

Cost-Effectiveness and Cost-Utility Analysis of Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome: Results From the PRECISE Study.

ObjectiveTo assess the cost‐effectiveness and cost‐utility of Spinal Cord Stimulation (SCS) in patients with failed back surgery syndrome (FBSS) refractory to conventional medical management (CMM).Materials and MethodsWe conducted an observational, multicenter, longitudinal ambispective study, where patients with predominant leg pain refractory to CMM expecting to receive SCS+CMM were recruited in 9 Italian centers and followed up to 24 months after SCS. We collected data on clinical status (pain intensity, disability), Health‐Related Quality‐of‐Life (HRQoL) and on direct and indirect costs before (pre‐SCS) and after (post‐SCS) the SCS intervention. Costs were quantified in € 2009, adopting the National Health Service's (NHS), patient and societal perspectives. Benefits and costs pre‐SCS versus post‐SCS were compared to estimate the incremental cost‐effectiveness and cost utility ratios.Results80 patients (40% male, mean age 58 years) were recruited. Between baseline and 24 months post‐SCS, clinical outcomes and HRQoL significantly improved. The EQ‐5D utility index increased from 0.421 to 0.630 (p < 0.0001). Statistically significant improvement was first observed six months post‐SCS. Societal costs increased from €6600 (pre‐SCS) to €13,200 (post‐SCS) per patient per year. Accordingly, the cost‐utility acceptability curve suggested that if decision makers' willingness to pay per Quality‐Adjusted‐Life‐Years (QALYs) was €60,000, SCS implantation would be cost‐effective in 80% and 85% of cases, according to the NHS's and societal point of views, respectively.ConclusionsOur results suggest that in clinical practice, SCS+CMM treatment of FBSS patients refractory to CMM provides good value for money. Further research is encouraged in the form of larger, long‐term studies.

Spinal cord stimulation in patients with painful diabetic neuropathy: A multicentre randomized clinical trial

Painful diabetic neuropathy (PDN) is a peripheral neuropathic pain condition that is often difficult to relieve. Spinal cord stimulation (SCS) is a proven effective therapy for various types of mixed neuropathic conditions, yet effectiveness of SCS treatment for PDN is not well established. To our knowledge, ours is the first multicentre randomized controlled trial investigating the effectiveness of SCS in patients with PDN. Sixty patients with PDN in the lower extremities refractory to conventional medical therapy were enrolled and followed for 6months. They were randomized 2:1 to best conventional medical practice with (SCS group) or without (control group) additional SCS therapy, and both groups were assessed at regular intervals. At each follow-up visit, the EuroQoL 5D, the short form McGill Pain Questionnaire (SF-MPQ) and a visual analogue scale (VAS, ranging 0–100) to measure pain intensity were recorded. The average VAS score for pain intensity was 73 in the SCS group and 67 in the control group at baseline. After 6months of treatment, the average VAS score was significantly reduced to 31 in the SCS group (P<.001) and remained 67 (P=.97) in the control group. The SF-MPQ and EuroQoL 5D questionnaires also showed that patients in the SCS group, unlike those in the control group, experienced reduced pain and improved health and quality of life after 6months of treatment. In patients with refractory painful diabetic neuropathy, spinal cord stimulation therapy significantly reduced pain and improved quality of life.

Utilization of Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome

Retrospective analysis of a population-based insurance claims data set. To evaluate the use of spinal cord stimulation (SCS) and lumbar reoperation for the treatment of failed back surgery syndrome (FBSS), and examine their associated complications and health care costs. FBSS is a major source of chronic neuropathic pain and affects up to 40% of patients who undergo lumbosacral spine surgery for back pain. Thus far, few economic analyses have been performed comparing the various treatments for FBSS, with these studies involving small sample sizes. In addition, the nationwide practices in the use of SCS for FBSS are unknown. The MarketScan data set was used to analyze patients with FBSS who underwent SCS or spinal reoperation between 2000 and 2009. Propensity score methods were used to match patients who underwent SCS with those who underwent lumbar reoperation to examine health care resource utilization. Postoperative complications were analyzed with multivariate logistic regression. Health care use was analyzed using negative binomial and general linear models. The study cohort included 16,455 patients with FBSS, with 395 undergoing SCS implantation (2.4%). Complication rates at 90 days were significantly lower for SCS than spinal reoperation (P < 0.0001). Also in the matched cohort, hospital stay (P < 0.0001) and associated charges (P = 0.016) were lower for patients with SCS. However outpatient, emergency room, and medication charges were similar between the 2 groups. Overall cost totaling $82,586 at 2 years was slightly higher in the lumbar reoperation group than in the SCS group with total cost of $80,669 (P = 0.88). Although previous studies have demonstrated superior efficacy for the treatment of FBSS, SCS remains underused. Despite no significant decreases in overall health care cost with SCS implantation, because it is associated with decreased complications and improved outcomes, this technology warrants closer consideration for the management of chronic pain in patients with FBSS.

Sustained Effectiveness of 10 kHz High-Frequency Spinal Cord Stimulation for Patients with Chronic, Low Back Pain: 24-Month Results of a Prospective Multicenter Study

ObjectiveThe aim of this study was to investigate the long-term efficacy and safety of paresthesia-free high-frequency spinal cord stimulation (HF10 SCS) for the treatment of chronic, intractable pain of the low back and legs.DesignProspective, multicenter, observational study.MethodPatients with significant chronic low back pain underwent implantation of a spinal cord stimulator capable of HF10 SCS. Patients' pain ratings, disability, sleep disturbances, opioid use, satisfaction, and adverse events were assessed for 24 months.ResultsAfter a trial period, 88% (72 of 82) of patients reported a significant improvement in pain scores and underwent the permanent implantation of the system. Ninety percent (65 of 72) of patients attended a 24-month follow-up visit. Mean back pain was reduced from 8.4 ± 0.1 at baseline to 3.3 ± 0.3 at 24 months (P < 0.001), and mean leg pain from 5.4 ± 0.4 to 2.3 ± 0.3 (P < 0.001). Concomitantly to the pain relief, there were significant decreases in opioid use, Oswestry Disability Index score, and sleep disturbances. Patients' satisfaction and recommendation ratings were high. Adverse Events were similar in type and frequency to those observed with traditional SCS systems.ConclusionsIn patients with chronic low back pain, HF10 SCS resulted in clinically significant and sustained back and leg pain relief, functional and sleep improvements, opioid use reduction, and high patient satisfaction. These results support the long-term safety and sustained efficacy of HF10 SCS.

PSY46 - Cost-utility analysis of spinal cord stimulation in patient with failed back surgery syndrome: Results from the precise study

PSY46 - Cost-utility analysis of spinal cord stimulation in patient with failed back surgery syndrome: Results from the precise study

Factors Associated with the Success of Trial Spinal Cord Stimulation in Patients with Chronic Pain from Failed Back Surgery Syndrome

ObjectiveSpinal cord stimulation (SCS) is an effective means of treatment of chronic neuropathic pain from failed back surgery syndrome (FBSS). Because the success of trial stimulation is an essential part of SCS, we investigated factors associated with success of trial stimulation.MethodsSuccessful trial stimulation was possible in 26 of 44 patients (63.6%) who underwent insertion of electrodes for the treatment of chronic pain from FBSS. To investigate factors associated with successful trial stimulation, patients were classified into two groups (success and failure in trial). We investigated the following factors : age, sex, predominant pain areas (axial, limb, axial combined with limbs), number of operations, duration of preoperative pain, type of electrode (cylindrical/paddle), predominant type of pain (nociceptive, neuropathic, mixed), degree of sensory loss in painful areas, presence of motor weakness, and preoperative Visual Analogue Scale.ResultsThere were no significant differences between the two groups in terms of age, degree of pain, number of operations, and duration of pain (p>0.05). Univariate analysis revealed that the type of electrode and presence of severe sensory deficits were significantly associated with the success of trial stimulation (p<0.05). However, the remaining variable, sex, type of pain, main location of pain, degree of pain duration, degree of sensory loss, and presence of motor weakness, were not associated with the trial success of SCS for FBSS.ConclusionTrial stimulation with paddle leads was more successful. If severe sensory deficits occur in the painful dermatomes in FBSS, trial stimulation were less effective.

Cerebrospinal Fluid Levels of Vascular Endothelial Growth Factor Correlate With Reported Pain and Are Reduced by Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome

Spinal cord stimulation (SCS) is an efficacious therapy for chronic neuropathic pain whose precise mechanism of action is unclear. Mediators produced by glial and immune cells are now believed to modulate neuronal transmission and promote chronic neuropathic pain. We postulated a relationship between cerebrospinal fluid (CSF) concentrations of neuroimmune mediators and SCS. We measured CSF concentrations of the chemokine, monocyte chemotactic protein-1 (MCP-1), and the growth factors, brain-derived neurotrophic factor (BDNF), and vascular endothelial growth factor (VEGF) and tested for relationships with stimulation parameters and clinical response in nine patients with failed back surgery syndrome (FBSS). Patients with FBSS had higher CSF concentrations of BDNF (p = 0.01) and MCP-1 (p = 0.0001) than matched controls. CSF concentrations of BDNF and VEGF correlated with reported pain (p = 0.04). Five minutes of SCS resulted in a reduction in median VEGF concentrations (p = 0.01). Patients with FBSS have altered CSF levels of BDNF and MCP-1. CSF VEGF correlates with pain and is reduced by SCS. This may offer novel insights into both the mechanism of action of SCS in FBSS and the variation in clinical response that may be encountered.

157 Utilization of Spinal Cord Stimulation in Patients with Failed Back Surgery Syndrome

undergoing SCS implantation (19.0% vs. 7.5%) Complications: The incidence of postoperative complications during the index hospitalization was significantly higher in those who underwent lumbar surgery (11.7%) compared to patients who underwent SCS (5.1%) (p < 0.0001). Even at 90 day follow-up, those in the lumbar surgery group experienced complications at more than 2 times the rate as those in the SCS group (14.4% vs. 6.5%, p < 0.0001) (Table 1). Conclusions

A Pilot Study to Evaluate the Safety and Feasibility of Spinal Cord Stimulation in Patients With Advanced Heart Failure

A Pilot Study to Evaluate the Safety and Feasibility of Spinal Cord Stimulation in Patients With Advanced Heart Failure

Trial of additional spinal cord stimulation in patients with implanted spinal cord stimulation system

Trial of additional spinal cord stimulation in patients with implanted spinal cord stimulation system

Spinal Cord Stimulation: Predictive Parameters of Outcome in Patients Suffering From Critical Lower Limb Ischemia. A Preliminary Study

The aim of our study is to identify the assessment of metabolic and dynamic capillaroscopy parameters that may be predictive of the outcome of spinal cord stimulation in patients affected with non-revascularisable chronic critical limb ischemia. Forty patients, 16 female and 24 male, average age 69 ± 8, underwent microcirculatory screening with transcutaneous oximetry and dynamic capillaroscopy. Microcirculatory assessment was performed before temporary implantation of the spinal cord stimulation stimulator and after one month. The following metabolic parameters were considered: TcPO2-TcPCO2 and with dependent limb, difference between dependent limb and supine values (Δ TcPO2, Δ TcPCO2), change in TcPO2-TcPCO2 after stimulation. Dynamic capillaroscopy parameters were recorded. Follow-up visits were scheduled at three, six, and twelve months after implantation. The procedure was performed placing an Octrode (St. Jude Medical, St. Paul, MN, USA) on the dorsal columns of the spinal cord. Two groups were identified on the basis of transcutaneous oximetry measurements: group A (22 patients) and group B (18 patients), responding differently to the postural test. After one month of home testing period, there was an improvement in metabolic parameters, differing from one group to the other. The morphofunctional data provided by capillaroscopy highlighted the percentage of open capillaries poststimulation as being a significant parameter, although not mentioned in previous studies. Spinal neuromodulation is an effective therapy option in the management of patients affected by non-reconstructable chronic critical limb ischemia.

The Use of Laminectomy for the Placement of a Percutaneous Spinal Cord Stimulation Electrode

The placement of a percutaneous electrode for trial stimulation to evaluate the effectiveness of spinal cord stimulation can be impossible because of epidural adhesions from previous spinal surgeries. The authors would like to describe a combination of techniques in order to place a percutaneous lead for a test phase. Technical report of an illustrative case where a partial laminectomy was used to assist a percutaneous lead placement. Adequate trial spinal cord stimulation with a single lead electrode at the right target area was possible. This case demonstrates the possibility to use a combination of an open and percutaneous technique for trial spinal cord stimulation in patients with prior operations in the target area of stimulation.

Spinal cord stimulation in patient with FBSS and aracnoiditis: Case report

Spinal cord stimulation in patient with FBSS and aracnoiditis: Case report

Spinal Cord Stimulation for Patients with Failed Back Surgery Syndrome: A Systematic Review

Background: Failed back surgery syndrome is common in the United States. Management of post lumbar surgery syndrome with multiple modalities includes interventional techniques, resulting in moderate improvement, leaving a proportion of patients in intractable pain. The systematic reviews of long-term benefits and risks of spinal cord stimulation (SCS) for patients with failed back surgery syndrome showed limited to moderate evidence and cost effectiveness. However, with the exponential increase in surgery in the United States, spinal cord implants are also increasing. Thus, the discussion continues with claims of lack of evidence on one hand and escalating increases in utilization on the other hand. Study Design: A systematic review of SCS in patients with failed back surgery syndrome. Objectives: This systematic review is undertaken to examine the evidence from randomized controlled trials (RCTs) and observational studies to evaluate the effectiveness of SCS in post lumbar surgery syndrome and to demonstrate clinical and cost effectiveness. Methods: Review of the literature was performed according to the Cochrane Musculoskeletal Review Group Criteria as utilized for interventional techniques for randomized trials and the Agency for Healthcare Research and Quality (AHRQ) criteria for observational studies. The 5 levels of evidence were classified as Level I, II, or III with 3 subcategories in Level II based on the quality of evidence developed by the U.S. Preventive Services Task Force (USPSTF). Data sources included relevant literature of the English language identified through searches of PubMed and EMBASE from 1966 to December 2008, and manual searches of bibliographies of known primary and review articles. Outcome Measures: The primary outcome measure was pain relief (short-term relief ≤ one-year and long-term &gt; one-year). Secondary outcome measures of improvement in functional status, psychological status, return to work, and reduction in opioid intake were utilized. Results: The indicated evidence is Level II-1 or II-2 for long-term relief in managing patients with failed back surgery syndrome. Limitations: The limitations of this review included the paucity and heterogeneity of the literature. Conclusion: This systematic review evaluating the effectiveness of SCS in relieving chronic intractable pain of failed back surgery syndrome indicated the evidence to be Level II-1 or II-2 for clinical use on a long-term basis. Key words: Chronic low back pain, neuropathic pain, failed back surgery syndrome, FBSS, post lumbar surgery syndrome, electrical stimulation, spinal cord stimulation