Combination therapy with simultaneous delivery of spinal cord stimulation modalities: COMBO randomized controlled trial.

Aim: The Combining Mechanisms for Better Outcomes randomized controlled trial assessed the effectiveness of various spinal cord stimulation (SCS) modalities for chronic pain. Specifically, combination therapy (simultaneous use of customized sub-perception field and paresthesia-based SCS) versus monotherapy (paresthesia-based SCS) was evaluated. Methods: Participants were prospectively enrolled (key inclusion criterion: chronic pain for ≥6 months). Primary end point was the proportion with ≥50% pain reduction without increased opioids at the 3 month follow-up. Patients were followed for 2 years. Results: The primary end point was met (n = 89; p < 0.0001) in 88% of patients in the combination-therapy arm (n = 36/41) and 71% in the monotherapy arm (n = 34/48). Responder rates at 1 and 2 years (with available SCS modalities) were 84% and 85%, respectively. Sustained functional outcomes improvement was observed out to 2 years. Conclusion: SCS-based combination therapy can improve outcomes in patients with chronic pain. Clinical Trial Registration: NCT03689920 (ClinicalTrials.gov), Combining Mechanisms for Better Outcomes (COMBO).

Spinal cord stimulation (SCS) is a device-based therapy for chronic pain that delivers electrical impulses to the spinal cord, disrupting pain signals to the brain. Pain relief can be achieved using different SCS techniques that use or do not use paresthesia (stimulation that produces a tingling sensation). These approaches affect patients in different ways, suggesting that different biological processes are involved in enabling pain relief. Research also suggests that better long-term results occur when patients can choose the therapy that is best for their own needs. This clinical study compared pain relief and other functional activities in those receiving combination therapy (simultaneous use of SCS that does and does not produce tingling sensation) against those receiving monotherapy (only SCS therapy producing tingling sensation) for 3 months. In the study, 88% of those receiving combination therapy and 71% with monotherapy alone reported a 50% (or greater) decrease in overall pain (the 'responder rate') without an increased dose of opioid drugs at 3 months after the start of therapy. This responder rate was found to be 84% at 1 year and 85% at 2 years (with all SCS therapy options available). Analysis of functional activities or disability showed that patients improved from 'severely disabled' at study start to 'moderately disabled' after 2 years, indicating that effective long-term (2 year) improvement can be achieved using SCS-based combination therapy for chronic pain.

An Integrated Quantitative Index for Measuring Chronic Multisite Pain: The Multiple Areas of Pain (MAP) Study.

OBJECTIVE: Despite the high prevalence of chronic multisite pain, there is little consensus on methods to characterize it. Commonly used assessments report only one dimension of pain, that is, intensity, thus ignoring the spatial aspect of pain. We developed a novel pain quantification index, the Integrated Pain Quantification Index (IPQI), on a scale of 0 to 1 that integrates multiple distinct pain measures into a single value, thus representing multidimensional pain information with a single value. DESIGN: Single-visit, noninterventional, epidemiological study. SETTING: Fourteen outpatient multidisciplinary pain management programs. PATIENTS: Patients with chronic pain of the trunk and/or limbs for at least six months with average overall pain intensity of at least 5 on the numeric rating scale. METHODS: Development of IPQI was performed in a large population (N = 810) of chronic pain patients from the Multiple Areas of Pain (MAP) study. RESULTS: Prevalence of two or more noncontiguous painful areas was at 88.3% (95% confidence interval [CI] = 0.86-0.90), with a mean of 6.3 areas (SD = 5.57 areas). Prevalence of more than 10% body area in pain was at 52.8% (95% CI = 0.49-0.56), with a mean at 16.1% (17.16%). On average, IPQI values were near the middle of the scale, with mean and median IPQI at 0.52 (SD = 0.13) and 0.55, respectively. The IPQI was generalizable and clinically relevant across all domains recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials. CONCLUSIONS: IPQI provided a single pain score for representing complex, multidimensional pain information on one scale and has implications for comparing pain populations across longitudinal clinical trials.

Lumbar transforaminal epidural dexamethasone: a prospective, randomized, double-blind, dose-response trial.

BACKGROUND AND OBJECTIVES: Serious adverse events related to particulate steroids have curtailed the use of transforaminal epidural steroid injections for radicular pain. Dexamethasone has been proposed as an alternative. We investigated the efficacy, dose-response profile, and safety of 3 doses of epidural dexamethasone. METHODS: A prospective, randomized, double-blind, dose-ranging design was used. A total of 98 subjects were randomized to transforaminal epidural dexamethasone 4 mg (n = 33), 8 mg (n = 33), or 12 mg (n = 32). The primary outcome measure for this study was reduction in radicular pain according to the visual analog scale from baseline, with 30% reduction or higher considered clinically meaningful. Secondary measures included the Oswestry Low Back Disability Scale, Subject Global Impression of Change, Subject Global Satisfaction Scale, and adverse events. Outcomes were assessed at 1, 4, 8, and 12 weeks after injection. Outcome measures, sample size, and statistical analysis were defined before enrollment. RESULTS: Mean radicular pain according to the visual analog scale compared with baseline was reduced 41.7%, 33.5%, and 26.6% at 4, 8, and 12 weeks, respectively, after injection. Oswestry disability ratings declined from "moderate" at baseline to "minimal" at 4, 8, and 12 weeks after injection. There was no statistical difference between groups for either measure (all P values < 0.05, Bonferroni-corrected). Parallel effects were observed in "impression of change" and "satisfaction" measures. No serious adverse events were noted. CONCLUSIONS: Transforaminal epidural dexamethasone provides statistically significant and clinically meaningful improvement in radicular pain at 12 weeks after injection, with parallel improvements in disability, impression of change, and satisfaction measures. There was no difference in efficacy for dexamethasone 4 mg compared with 8 or 12 mg. The optimal dose of epidural dexamethasone may be lower than 4 mg, further increasing the long-term safety and tolerability of this treatment. Current data are reassuring with regard to the safety of dexamethasone for transforaminal epidural steroid injection.

Pulsed radiofrequency neurotomy: advances in pain medicine.

In the past three decades, radiofrequency neurotomy (RFN) has been established as a safe and effective treatment for facet and sacroiliac arthropathy. However, early reports of deafferentation pain syndromes and motor deficit with the application of radiofrequency lesions to other neural structures effectively halted further development of this technology for other applications until recent years. Pulsed radiofrequency neurotomy (PRFN) represents the most recent advance in radiofrequency technology in clinical practice. PRFN allows for application of radiofrequency current at markedly lower tissue temperatures, thereby minimizing the risk of adverse events. The initial clinical data on PRFN demonstrate response rates similar to conventional high temperature RFN lesions for facet and sacroiliac arthropathy and a host of other chronic pain disorders.

Acupuncture in pain medicine: an integrated approach to the management of refractory pain.

As the acupuncture nomenclature permeates medical literature, the artificial barriers to integration of acupuncture and allopathic medicine are disappearing. More patients are looking to their physicians for guidance on how to incorporate acupuncture into their health care, and pain physicians are accepting the challenge. Similar to allopathic medicine, acupuncture is an intricate diagnostic and therapeutic system. However, for practicing physicians, mastery of the skills necessary for safe and effective treatment of many conditions is well within reach. Used in an integrated medical model, acupuncture is well suited to deal with many of the functional problems that allopathic medicine is not equipped to address. The result is patient and physician satisfaction.