Predictors of pain relief following spinal cord stimulation in chronic back and leg pain and failed back surgery syndrome: a systematic review and meta-regression analysis

This is the final version of the article. Available from the publisher via the DOI in this record.We sought to assess the extent to which pain relief in chronic back and leg pain (CBLP) following spinal cord stimulation (SCS) is influenced by patient-related factors, including pain location, and technology factors. A number of electronic databases were searched with citation searching of included papers and recent systematic reviews. All study designs were included. The primary outcome was pain relief following SCS, we also sought pain score (pre- and post-SCS). Multiple predictive factors were examined: location of pain, history of back surgery, initial level of pain, litigation/worker's compensation, age, gender, duration of pain, duration of follow-up, publication year, continent of data collection, study design, quality score, method of SCS lead implant, and type of SCS lead. Between-study association in predictive factors and pain relief were assessed by meta-regression. Seventy-four studies (N = 3,025 patients with CBLP) met the inclusion criteria; 63 reported data to allow inclusion in a quantitative analysis. Evidence of substantial statistical heterogeneity (P < 0.0001) in level of pain relief following SCS was noted. The mean level of pain relief across studies was 58% (95% CI: 53% to 64%, random effects) at an average follow-up of 24 months. Multivariable meta-regression analysis showed no predictive patient or technology factors. SCS was effective in reducing pain irrespective of the location of CBLP. This review supports SCS as an effective pain relieving treatment for CBLP with predominant leg pain with or without a prior history of back surgery. Randomized controlled trials need to confirm the effectiveness and cost-effectiveness of SCS in the CLBP population with predominant low back pain.This study was sponsored by Medtronic, Inc

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

This is the final version of the article. Available from the publisher via the DOI in this record.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® 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. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01697358 (http://www.clinicaltrials.gov).The study is funded by Medtronic In

Prognostic molecular markers with no impact on decision-making: the paradox of gliomas based on a prospective study

This study assessed the prognostic value of several markers involved in gliomagenesis, and compared it with that of other clinical and imaging markers already used. Four-hundred and sixteen adult patients with newly diagnosed glioma were included over a 3-year period and tumour suppressor genes, oncogenes, MGMT and hTERT expressions, losses of heterozygosity, as well as relevant clinical and imaging information were recorded. This prospective study was based on all adult gliomas. Analyses were performed on patient groups selected according to World Health Organization histoprognostic criteria and on the entire cohort. The endpoint was overall survival, estimated by the Kaplan–Meier method. Univariate analysis was followed by multivariate analysis according to a Cox model. p14ARF, p16INK4A and PTEN expressions, and 10p 10q23, 10q26 and 13q LOH for the entire cohort, hTERT expression for high-grade tumours, EGFR for glioblastomas, 10q26 LOH for grade III tumours and anaplastic oligodendrogliomas were found to be correlated with overall survival on univariate analysis and age and grade on multivariate analysis only. This study confirms the prognostic value of several markers. However, the scattering of the values explained by tumour heterogeneity prevents their use in individual decision-making

The appropriate management of persisting pain after spine surgery: a European panel study with recommendations based on the RAND/UCLA method

Purpose: Management of patients with persisting pain after spine surgery (PPSS) shows significant variability, and there is limited evidence from clinical studies to support treatment choice in daily practice. This study aimed to develop patient-specific recommendations on the management of PPSS. Methods: Using the RAND/UCLA appropriateness method (RUAM), an international panel of 6 neurosurgeons, 6 pain specialists, and 6 orthopaedic surgeons assessed the appropriateness of 4 treatment options (conservative, minimally invasive, neurostimulation, and re-operation) for 210 clinical scenarios. These scenarios were unique combinations of patient characteristics considered relevant to treatment choice. Appropriateness had to be expressed on a 9-point scale (1 = extremely inappropriate, 9 = extremely appropriate). A treatment was considered appropriate if the median score was ≥ 7 in the absence of disagreement (≥ 1/3 of ratings in each of the opposite sections 1–3 and 7–9). Results: Appropriateness outcomes showed clear and specific patterns. In 48% of the scenarios, exclusively one of the 4 treatments was appropriate. Conservative treatment was usually considered appropriate for patients without clear anatomic abnormalities and for those with new pain differing from the original symptoms. Neurostimulation was considered appropriate in the case of (predominant) neuropathic leg pain in the absence of conditions that may require surgical intervention. Re-operation could be considered for patients with recurrent disc, spinal/foraminal stenosis, or spinal instability. Conclusions: Using the RUAM, an international multidisciplinary panel established criteria for appropriate treatment choice in patients with PPSS. These may be helpful to educate physicians and to improve consistency and quality of care. Graphical abstract: These slides can be retrieved under Electronic Supplementary Material. [Figure not available: see fulltext.

Failed back surgery syndrome: what's in a name? A proposal to replace “FBSS” by “POPS”…

Background: The current definition of Failed Back Surgery Syndrome (FBSS) has a pejorative and restrictive connotation of blame and failure. Optimally, the evaluation of FBSS patients might be based on a multidimensional approach, involving an array of practitioners including spine surgeons, pain physicians, physiotherapists and behavioural specialists. Even though these clinical interactions should lead to a unique approach, one main problem comes from the fact that FBSS definition has varied over time and remains extremely controversial. There is now a need for global consensus about what we call FBSS, why, when and how. Discussing the name of this syndrome appears to be a logical starting point. Discussion: “PostOperative Persistent Syndrome”, summarised by the acronym “POPS”, could be an appropriate term to not only encapsulate failure but pain, function and psychosocial dysfunction following unsuccessful spine surgery whether from a technical or expectation standpoint. A return to the source might help to identify the real clinical problem, i.e. the pain mechanism: nociceptive, neuropathic pain or mixed. A clinical and radiological spine assessment is key to ensure that no further surgery is required, by distinguishing within the so-called FBSS population, “true” FBSS patients and “potential” FBSS patients, who are actually not FBSS patients, as an aetiological treatment of potential pain generators still remains possible. Conclusion: We propose to replace the FBSS acronym by POPS. The ultimate goal of this redefinition would be to guide the patient towards the future rather than the past and to reach a consensus, based on network discussions, concerning the following items: integrate pain mechanisms into the diagnostic process; implement the notion of a predominant ratio between mechanical/neuropathic pain mechanisms, which defines the potential target for treatment options; create a network supported by a database, to prospectively pool and analyse data, using homogeneous evaluation tools and ultimately define outcome predictors in this population

Evaluation of fracture properties of cancellous bone tissues using digital image correlation/wedge splitting test method

International audienceThe fracture mechanics (FM) parameters of cancellous bone tissues are very important from a clinical point of view especially for the bone cement augmentation. From the literature review, one can observe that the experimental determination of fracture mechanic parameters of cancellous bone are still lacking. This can be due to the conditions associated with the unstable crack propagation in the cancellous bone and lack of tools to extract and measure the parameters (like crack opening displacement (COD) and crack length) in the course of fracture tests, which are necessary to evaluate the fracture properties. To address above mentioned, a platform was developed integrating an optical measurement technique like digital image correlation (DIC) with classical wedge splitting test (WST) method to extract precise and real crack tip positions, crack opening displacement (COD) at each load step. These indeed used for the evaluation of the fracture mechanic properties (fracture toughness, specific fracture energy ()) of the cancellous bone. Two approaches were used to evaluate the fracture mechanic properties of the bone. The first method is based on the global approach, which was widely used in the literature and the second method is based on the local approach. In this local approach, the local fracture energy () during the course of the test was evaluated, which give access to local fracture mechanics. The results evaluated by both the methods were in good accordance and compared with available literature. In addition, an attempt made to retrieve the real crack tip position at each load step during the test

Optimal medical, rehabilitation and behavioral management in the setting of failed back surgery syndrome

Introduction: Failed back surgery syndrome (FBSS) constitutes a constellation of symptoms grouped together and attributed to prior surgical intervention. Clinicians often poorly understand the heterogeneity of this condition combined with the etiological factors responsible for its development. Therefore, it would follow that an algorithmic treatment approach to patients diagnosed with this syndrome might pose challenges. The clinical work-up of the patient involves history, examination and appropriate diagnostic imaging as well as behavioral assessment. Materials and methods: We sought to conduct a narrative review of the available literature focused on the medical, rehabilitative and behavioral treatment of FBSS. To that end, we conducted a literature search using PubMed (through March 2013). We focused on studies published over the last 20 years. Only English language articles were included. Search terms included “failed back surgery syndrome”, “FBSS”, “failed back syndrome”, and “post-laminectomy syndrome”. Studies included in our review focused on randomized controlled trials (RCTs), prospective cohort studies, and case series (retrospective and prospective). Studies were organized by intervention (e.g. medical management, physical therapy and rehabilitation, and psychosocial) and presented to emphasize the quality of evidence (e.g. RCTs, prospective studies, etc.). Conclusion: Overall, the literature provides very limited guidance on the comprehensive management of patients suffering from FBSS. There are rehabilitative interventions and behavioral protocols that demonstrate promise. Pathways based on medication management remain difficult to clearly define