Change in Pain-Related Anxiety Mediates the Effects of Psychophysiologic Symptom Relief Therapy (PSRT) on Pain Disability for Chronic Back Pain: Secondary Results from a Randomized Controlled Trial.

Purpose: Widely used therapeutic approaches, such as cognitive-behavioral and mindfulness-based therapies, can improve pain and functioning in people with chronic back pain, but the magnitude and duration of their effects are limited. Our team developed a novel 12-week program, psychophysiologic symptom relief therapy (PSRT), to substantially reduce or eliminate pain and disability. This study examined whether PSRT helped more patients achieve large-magnitude (≥30%, ≥50%, ≥75%) reductions in back pain-related disability compared to mindfulness-based stress reduction (MBSR) and usual care (UC), and if the beneficial effects of PSRT were explained by reductions in pain-related anxiety following treatment. Patients and Methods: Data from a three-armed randomized controlled trial were used (N=35 adults with chronic back pain). Change scores (baseline to 4-, 8-, 13-, and 26-weeks post-enrollment) were computed for back pain disability (RDQ) and pain-related anxiety (PASS-20). Fisher's exact tests and mediation analyses were conducted. Results: Compared to MBSR and UC, PSRT helped significantly more patients achieve ≥75% reductions in back pain disability at all timepoints and in pain anxiety at all timepoints except 13-weeks. Change in pain anxiety significantly mediated the relationship between treatment group and change in back pain disability from baseline to 26-weeks. Conclusion: PSRT helped more patients achieve substantial reductions in disability than an established treatment (MBSR) and usual care. Findings indicate reduced pain anxiety may be a mechanism by which PSRT confers long-term benefits on disability. Importantly, this work aims to move the field toward more precise and effective treatment for chronic back pain.

Failed Back Surgery Syndrome: No Longer a Surgeon's Defeat-A Narrative Review.

The introduction of the term Persistent Spinal Pain Syndrome (PSPS-T1/2), replacing the older term Failed Back Surgery Syndrome (FBSS), has significantly influenced our approach to diagnosing and treating post-surgical spinal pain. This comprehensive review discusses this change and its effects on patient care. Various diagnostic methods are employed to elucidate the underlying causes of back pain, and this information is critical in guiding treatment decisions. The management of PSPS-T1/2 involves both causative treatments, which directly address the root cause of pain, and symptomatic treatments, which focus on managing the symptoms of pain and improving overall function. The importance of a multidisciplinary and holistic approach is emphasized in the treatment of PSPS-T1/2. This approach is patient-centered and treatment plans are customized to individual patient needs and circumstances. The review concludes with a reflection on the impact of the new PSPS nomenclature on the perception and management of post-surgical spinal pain.

Needs and Attitudes of Older Chronic Back Pain Patients towards a Wearable for Ultrasound Biofeedback during Stabilization Exercises: A Qualitative Analysis.

Chronic back pain has a high prevalence, especially in older adults, and seriously affects sufferers' quality of life. Segmental stabilization exercise (SSE) is often used during physiotherapy to enhance core stability. The execution of SSE requires the selective contraction of deep abdominal and back muscles. Motor learning can be supported using ultrasound imaging as visual biofeedback. ULTRAWEAR is a mobile ultrasound system that provides deep learning-based biofeedback on SSE execution, which is currently under development. We interviewed 15 older chronic back pain patients (CBPPs) to investigate their pain management behavior, experience with SSE, as well as their needs and requirements for ULTRAWEAR. We also gathered information about future-usage scenarios. CBPPs reported a high willingness to use the system as a feedback tool both in physiotherapeutic practices and at home. The automated detection and evaluation of muscle contraction states was highlighted as a major benefit of the system compared to the more subjective feedback provided by traditional methods such as palpation. The system to be developed was perceived as a helpful solution to support learning about SSE.

Moderators and Nonspecific Predictors of Treatment Benefits in a Randomized Trial of Mindfulness-Based Stress Reduction vs Cognitive-Behavioral Therapy vs Usual Care for Chronic Low Back Pain.

Both mindfulness-based stress reduction (MBSR) and cognitive-behavioral therapy (CBT) are effective for chronic low back pain (CLBP), but little is known regarding who might benefit more from one than the other. Using data from a randomized trial comparing MBSR, CBT, and usual care (UC) for adults aged 20 to 70 years with CLBP (N = 297), we examined baseline characteristics that moderated treatment effects or were associated with improvement regardless of treatment. Outcomes included 8-week function (modified Roland Disability Questionnaire), pain bothersomeness (0-10 numerical rating scale), and depression (Patient Health Questionnaire-8). There were differences in the effects of CBT versus MBSR on pain based on participant gender (P = .03) and baseline depressive symptoms (P = .01), but the only statistically significant moderator after Bonferroni correction was the nonjudging dimension of mindfulness. Scores on this measure moderated the effects of CBT versus MBSR on both function (P = .001) and pain (P = .04). Pain control beliefs (P <.001) and lower anxiety (P < .001) predicted improvement regardless of treatment. Replication of these findings is needed to guide treatment decision-making for CLBP. TRIAL REGISTRATION: The trial and analysis plan were preregistered in ClinicalTrials.gov (Identifier: NCT01467843). PERSPECTIVE: Although few potential moderators and nonspecific predictors of benefits from CBT or MBSR for CLBP were statistically significant after adjustment for multiple comparisons, these findings suggest potentially fruitful directions for confirmatory research while providing reassurance that patients could reasonably expect to benefit from either treatment.

Barriers to accessing health care for people with chronic conditions: a qualitative interview study.

BACKGROUND: There is a growing interest in redesigning healthcare systems to increase access to and coordination across care settings for people with chronic conditions. We aim to gain a better understanding of the barriers faced by (1) children with chronic bronchial asthma, (2) adults with non-specific chronic back pain, and (3) older people with pre-existing mental illness/es in Austria's fragmented social health insurance system. METHODS: Using a qualitative design, we conducted semi-structured interviews face-to-face and by telephone with health service providers, researchers, experts by experience (persons with lived/ personal experience, i.e., service users, patient advocates or family members/carers), and employees in public health administration between July and October 2019. The analysis and interpretation of data were guided by Levesque's model of access, a conceptual framework used to evaluate access broadly according to different dimensions of accessibility to care: approachability, acceptability, availability and accommodation, affordability, and appropriateness. RESULTS: The findings from the 25 expert interviews were organised within Levesque's conceptual framework. They highlight a lack of coordination and defined patient pathways, particularly at the onset of the condition, when seeking a diagnosis, and throughout the care process. On the supply side, patterns of poor patient-provider communication, lack of a holistic therapeutic approach, an urban-rural divide, strict separation between social care and the healthcare system and limited consultation time were among the barriers identified. On the demand side, patients' ability to perceive a need and to subsequently seek and reach healthcare services was an important barrier, closely linked to a patient's socio-economic status, health literacy and ability to pay. CONCLUSIONS: While studies on unmet needs suggest a very low level of barriers to accessing health care in the Austrian context, our study highlights potential 'invisible' barriers. Barriers to healthcare access are of concern for patients with chronic conditions, underlining existing findings about the need to improve health services according to patients' specific needs. Research on how to structure timely and integrated care independent of social and economic resources, continuity of care, and significant improvements in patient-centred communication and coordination of care would be paramount.

Understanding the role of patient preference in the treatment algorithm for chronic low back pain: results from a survey-based study.

Aims: Interventional pain treatments range from injections to established radiofrequency ablation techniques and finally neuromodulation. In addition to safety, efficacy and cost dominance, patient preference for type of treatment is important. Methods: Chronic pain patients (n = 129) completed a preference scale to determine which interventional pain management procedures they would prefer from among radiofrequency ablation, temporary (60-day) peripheral nerve stimulation (PNS), conventional PNS and spinal cord stimulation/dorsal root ganglion stimulation. A second survey (n = 347) specific to assessing the preference for radiofrequency ablation or temporary PNS treatment was completed by patients with low back pain. Results: On the basis of mean rank, temporary PNS percutaneously implanted for up to 60 days was the most preferred treatment compared with the other options presented (p = 0.002). Conclusions: Patient preference should be unbiased and considered as an independent variable for physician discussion in treatment options and future research.

Patient preference is an important variable for physicians to consider when discussing treatment options for low back pain. A consumer survey study was completed discussing patient preference among various invasive treatments for low back pain. When given scenarios discussing risks and benefits of each procedure (temporary peripheral nerve stimulation for 60 days, heat ablation of small back nerves and permanently implanted back pain devices) temporary peripheral nerve stimulation was considered the preferred option.

Effect of Balneotherapy on Chronic Low Back Pain at Hot Springs in Southern Ethiopia: Perceived Improvements from Pain.

BACKGROUND: Low back pain (LBP) is an important musculoskeletal condition results in clinical, social and public health problems globally. Hydrotherapy, using water and heat together can be utilized to treat conditions, relieve pain and increase muscular power and a range of joint movement in patients with chronic lower back pain. Most patients with acute LBP improve spontaneously within four weeks; however, chronic LBP is extremely common and usually mechanical in nature. OBJECTIVE: The objective of the current study was to assess effect of balneotherapy in decreasing the lower back pain and its improvements among adults using a spa in southern Ethiopia. METHODS: We employed a single arm cohort study and convenient sampling method to select 442 study participants from four hot springs located in Sidama Region and Gedeo Zone, Southern Ethiopia. Structured and pretested questionnaire was used and administered face-to-face by trained data collectors. Data were entered using EpiData and transferred to SPSS for cleaning and analysis. Descriptive and bivariate analyses were made. RESULTS: A total of 427 participants were included in the study giving response rate of 96.6%. The mean (standard deviation) age of respondents was 42.55 (±14.92) years. Perceived improvement from back pain was 332 (77.8%) with 95% confidence interval (CI) of 74-82%. Factors showing association with perceived improvement from back pain after spa therapy were, study site being near Hawassa (Burkitu) with crude odds ratio (COR) of 3.3 and 95%CI: 1.83-5.98 and p-value <0.001; and sex of respondents that the odds of perceived improvements among males were about twofold compared with females, (COR: 1.7, 95%CI: 1.07-2.74, p-value 0.025. CONCLUSION: Our study shows significant perceived improvement from back pain after utilization of spa water. This is associated with type of hot spring used, male sex, and having neurological symptoms. Therefore, hot spring spa water had better therapeutic effect for back pain and emphasis should be given to integrate it with modern medicine and further experimental study to be conducted to recommend it for medical purposes.

Treatment of chronic axial back pain with 60-day percutaneous medial branch PNS: Primary end point results from a prospective, multicenter study.

BACKGROUND: The objective of this prospective, multicenter study is to characterize responses to percutaneous medial branch peripheral nerve stimulation (PNS) to determine if results from earlier, smaller single-center studies and reports were generalizable when performed at a larger number and wider variety of centers in patients recalcitrant to nonsurgical treatments. MATERIALS & METHODS: Participants with chronic axial low back pain (LBP) were implanted with percutaneous PNS leads targeting the lumbar medial branch nerves for up to 60 days, after which the leads were removed. Participants were followed long-term for 12 months after the 2-month PNS treatment. Data collection is complete for visits through end of treatment with PNS (primary end point) and 6 months after lead removal (8 months after start of treatment), with some participant follow-up visits thereafter in progress. RESULTS: Clinically and statistically significant reductions in pain intensity, disability, and pain interference were reported by a majority of participants. Seventy-three percent of participants were successes for the primary end point, reporting clinically significant (≥30%) reductions in back pain intensity after the 2-month percutaneous PNS treatment (n = 54/74). Whereas prospective follow-up is ongoing, among those who had already completed the long-term follow-up visits (n = 51), reductions in pain intensity, disability, and pain interference were sustained in a majority of participants through 14 months after the start of treatment. CONCLUSION: Given the minimally invasive, nondestructive nature of percutaneous PNS and the significant benefits experienced by participants who were recalcitrant to nonsurgical treatments, percutaneous PNS may provide a promising first-line neurostimulation treatment option for patients with chronic axial back pain.

Pain Management in Neurosurgery: Back and Lower Extremity Pain, Trigeminal Neuralgia.

Interventional anesthetic techniques are an integral component of a biopsychosocial approach and multidisciplinary treatment. Injection techniques are often used to diagnose disorders, decrease the need for surgery, or increase the time to surgery. The role of neural blockade techniques using local anesthetics and steroids in the assessment and treatment of pain continues to be refined. With the current opioid crisis and an aging population with increasing medical comorbidities, there is an emphasis on the use of nonopioid, nonsurgical, and multimodal therapies to treat chronic pain. This article reviews indications, goals, and methods of common injection techniques.

Animal models of regenerative medicine for biological treatment approaches of degenerative disc diseases.

Degenerative disc disease (DDD) is a painful, chronic and progressive disease, which is characterized by inflammation, structural and biological deterioration of the intervertebral disc (IVD) tissues. DDD is specified as cell-, age-, and genetic-dependent degenerative process that can be accelerated by environmental factors. It is one of the major causes of chronic back pain and disability affecting millions of people globally. Current treatment options, such as physical rehabilitation, pain management, and surgical intervention, can provide only temporary pain relief. Different animal models have been used to study the process of IVD degeneration and develop therapeutic options that may restore the structure and function of degenerative discs. Several research works have depicted considerable progress in understanding the biological basis of disc degeneration and the therapeutic potentials of cell transplantation, gene therapy, applications of supporting biomaterials and bioactive factors, or a combination thereof. Since animal models play increasingly significant roles in treatment approaches of DDD, we conducted an electronic database search on Medline through June 2020 to identify, compare, and discuss publications regarding biological therapeutic approaches of DDD that based on intradiscal treatment strategies. We provide an up-to-date overview of biological treatment strategies in animal models including mouse, rat, rabbit, porcine, bovine, ovine, caprine, canine, and primate models. Although no animal model could profoundly reproduce the clinical conditions in humans; animal models have played important roles in specifying our knowledge about the pathophysiology of DDD. They are crucial for developing new therapy approaches for clinical applications.

Effect of Psycho-Regulatory Massage Therapy on Pain and Depression in Women with Chronic and/or Somatoform Back Pain: A Randomized Controlled Trial.

Chronic unspecific back pain (cBP) is often associated with depressive symptoms, negative body perception, and abnormal interoception. Given the general failure of surgery in cBP, treatment guidelines focus on conservative therapies. Neurophysiological evidence indicates that C-tactile fibers associated with the oxytonergic system can be activated by slow superficial stroking of the skin in the back, shoulder, neck, and dorsal limb areas. We hypothesize that, through recruitment of C-tactile fibers, psycho-regulatory massage therapy (PRMT) can reduce pain in patients with cBP. In our study, 66 patients were randomized to PRMT or CMT (classical massage therapy) over a 12-week period and tested by questionnaires regarding pain (HSAL= Hamburger Schmerz Adjektiv Liste; Hamburg Pain adjective list), depression (BDI-II = Beck depression inventory), and disability (ODI = Oswestry Disability Index). In all outcome measures, patients receiving PRMT improved significantly more than did those receiving CMT. The mean values of the HSAL sensory subscale decreased by -51.5% in the PRMT group compared to -6.7% in the CMT group. Depressive symptoms were reduced by -55.69% (PRMT) and -3.1% (CMT), respectively. The results suggest that the superiority of PRMT over CMT may rely on its ability to activate the C-tactile fibers of superficial skin layers, recruiting the oxytonergic system.

Necrotizing fasciitis caused by the treatment of chronic non-specific back pain.

BACKGROUND: Chronic back pain is a multifactorial disease that occurs particularly in adults and has many negative effects on the quality of daily life. Therapeutic strategies are often multimodal and designed for a long-term therapy period. In some cases, one option is joint infiltration or intrathecal injection with local anaesthetics. An adverse effect of this intervention may be necrotic fasciitis, a disease with high mortality and few therapeutic options. CASE PRESENTATION: This case shows a 53-year-old female patient who developed necrotic fasciitis after infiltrations of the sacroiliac joint and after epidural-sacral and intrathecal injections. CONCLUSION: Thanks to early and aggressive surgical intervention, antibiotic treatment and hyperbaric oxygenation, she survived this serious complication and was able to return to life.

Peripheral Nerve Field Stimulation for Chronic Back Pain: Therapy Outcome Predictive Factors.

OBJECTIVE: To identify variables that influence pain reduction following peripheral nerve field stimulation (PNFS) in order to identify a potential responder profile. METHODS: Exploratory univariate and multivariate (random forest) analyses were performed separately on 2 randomized controlled trials and a registry; all included patients with chronic back pain, mainly failed back surgery syndrome. An international expert panel judged the clinical relevance of variables to identify responders by consensus. RESULTS: Variables identified that may help predict PNFS success in patients with back pain include patient and pain characteristics (age, time since onset of pain and spinal surgery, pain medication history, position and size of pain area, pain severity, mixed nociceptive/neuropathic pain, health-related quality of life, depression, functional disability, and leg pain status), implant procedure variables (the number and position of leads, paresthesia coverage, and amount of pain relief during the trial), and programming (number of programs, cathodes, and anodes; pulse rate; pulse width; and percentage of device usage). CONCLUSIONS: While these analyses are exploratory and restricted to a limited sample size, they suggest variables that may play a role in predicting a therapeutic response. These results, however, are informative only and should be cautiously interpreted. Future research to validate the variables in a clinical study is needed.

VA/DoD Clinical Practice Guideline: Diagnosis and Treatment of Low Back Pain.

DESCRIPTION: In September 2017, the U.S. Department of Veterans Affairs (VA) and U.S. Department of Defense (DoD) approved the joint Clinical Practice Guideline (CPG) for Diagnosis and Management of Low Back Pain. This CPG was intended to provide healthcare providers a framework by which to evaluate, treat, and manage patients with low back pain (LBP). METHODS: The VA/DoD Evidence-Based Practice Work Group convened a joint VA/DoD guideline development effort that included a multidisciplinary panel of practicing clinician stakeholders and conformed to the Institute of Medicine's tenets for trustworthy clinical practice guidelines. The guideline panel developed key questions in collaboration with the ECRI Institute, which systematically searched and evaluated the literature through September 2016, developed an algorithm, and rated recommendations by using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. A patient focus group was also convened to ensure patient values and perspectives were considered when formulating preferences and shared decision making in the guideline. RECOMMENDATIONS: The VA/DOD LBP CPG provides evidence-based recommendations for the diagnostic approach, education and self-care, non-pharmacologic and non-invasive therapy, pharmacologic therapy, dietary supplements, non-surgical invasive therapy, and team approach to treatment of low back pain.

[Efficacy of biofeedback in patients with chronic low back pain : Impact on pain intensity, psychological factors and stress markers]. / Effektivität von Biofeedback bei Patienten mit chronischem Rückenschmerz : Einfluss auf Schmerz, psychologische Faktoren und Stressmarker.

BACKGROUND: The treatment of patients with chronic pain should be carried out in interdisciplinary multimodal pain programs of which relaxation methods represent an integral part. The German disease management guidelines (NDGM) on nonspecific low back pain currently do not recommend biofeedback as a relaxation technique for chronic low back pain due to inadequate data. Furthermore, health insurances do not cover the costs of this treatment. METHODS: The efficacy of a 2-week biofeedback treatment was evaluated in a study of 10 patients with chronic nonspecific low back pain and 10 healthy, age and gender-matched subjects. The parameters "well-being", "depressive mood" and "pain-related disability" were assessed based on three psychometric tests (KAB, ADS and PDI). The pain intensity was measured using a numeric rating scale (NRS) and biofeedback measurement parameters themselves as well as stress markers in blood (noradrenaline, cortisol and MMP-2) were also measured. RESULTS: The relaxation response was demonstrated by the biofeedback-parameters. The treatment led to an improvement in well-being, depressive mood and pain-related disability. These results correlated with a reduction of noradrenaline and MMP-2 blood levels, whereas cortisol concentrations showed no change. CONCLUSION: Biofeedback relaxation is a suitable method in the treatment of chronic non-specific low back pain. Its use in interdisciplinary multimodal pain programs should be encouraged.

Efficacy of Biofeedback in Chronic back Pain: a Meta-Analysis.

PURPOSE: The aims of the present analysis were to investigate the short- and long-term efficacy and treatment moderators of biofeedback as a psychological treatment option for chronic back pain. METHOD: A literature search using PubMed, PsycINFO, and the Cochrane Library identified 21 eligible studies including 23 treatment conditions and 1062 patients. RESULTS: Meta-analytic integration resulted in a significant small-to-medium effect size for pain intensity reduction (Hedges' g = 0.60; 95 % confidence interval (CI) 0.44, 0.76) that proved to be stable with a significant small-to-large effect size (Hedges' g = 0.62; 95 % CI 0.40, 0.84) over an average follow-up phase of 8 months. Biofeedback also proved to be effective in reducing depression (Hedges' g = 0.40; 95 % CI 0.27, 0.52), disability (Hedges' g = 0.49; 95 % CI 0.34, 0.74), reduction of muscle tension (EMG; Hedges' g = 0.44; 95 % CI 0.22, 0.65), and improving cognitive coping (Hedges' g = 0.41; 95 % CI 0.26, 0.57). These effects remained comparatively stable at follow-up and for controlled studies only. Moderator analyses revealed longer biofeedback treatments to be more effective for reducing disability and a greater proportion of biofeedback in the treatment to be more effective for reducing depression. Publication bias analyses demonstrated the consistency of these effects. CONCLUSION: It is concluded that biofeedback treatment can lead to improvements on various pain-related outcomes in the short and long terms, both as a standalone and as an adjunctive intervention.

Eye Movement Desensitization and Reprocessing vs. Treatment-as-Usual for Non-Specific Chronic Back Pain Patients with Psychological Trauma: A Randomized Controlled Pilot Study.

OBJECTIVE: Eye movement desensitization and reprocessing (EMDR)-an evidence-based approach to eliminate emotional distress from traumatic experiences-was recently suggested for the treatment of chronic pain. The aim of this study was to estimate preliminary efficacy of a pain-focused EMDR intervention for the treatment of non-specific chronic back pain (CBP). DESIGN: Randomized controlled pilot study. METHODS: 40 non-specific CBP (nsCBP) patients reporting previous experiences of psychological trauma were consecutively recruited from outpatient tertiary care pain centers. After baseline assessment, patients were randomized to intervention or control group (1:1). The intervention group received 10 sessions standardized pain-focused EMDR in addition to treatment-as-usual (TAU). The control group received TAU alone. The primary outcome was preliminary efficacy, measured by pain intensity, disability, and treatment satisfaction from the patients' perspective. Clinical relevance of changes was determined according to the established recommendations. Assessments were conducted at the baseline, posttreatment, and at a 6-month follow-up. Intention-to-treat analysis with last observation carried forward method was used. Registered with http://ClinicalTrials.gov (NCT01850875). RESULTS: Estimated effect sizes (between-group, pooled SD) for pain intensity and disability were d = 0.79 (CI95%: 0.13, 1.42) and d = 0.39 (CI95%: -0.24, 1.01) posttreatment, and d = 0.50 (CI95%: 0.14, 1.12) and d = 0.14 (CI95%: -0.48, 0.76) at 6-month follow-up. Evaluation on individual patient basis showed that about 50% of the patients in the intervention group improved clinically relevant and also rated their situation as clinically satisfactory improved, compared to 0 patients in the control group. CONCLUSION: There is preliminary evidence that pain-focused EMDR might be useful for nsCBP patients with previous experiences of psychological trauma, with benefits for pain intensity maintained over 6 months.

The Effects of Moxibustion on Chronic Back Pain and Activities of Daily Living in Aged / 재활간호학회지

PURPOSE: This study was attempted in order to verify the effects of moxibustion on aged back pain and activities of daily living. METHODS: A research design is quasi-experiment with pre-post test design in nonequivalent control group. As for data collection and experimental treatment, it accidentally sampled totally 50 people with 24 people for the experimental group and 26 people for the control group who appeal for chronic back pain aged over 60 who visited 4 senior centers where are located in N city from November 7, 2012 to December 3, 2012. Experimental treatment was carried out moxibustion totally 12 times by 3 times for 4 weeks in the experimental group. Data analysis was made by using SPSS program. As an analytical technique, the experimental group and the control group were analyzed the homogeneity verification with t-test, Fisher's exact test and chi2 test and the hypothesis verification with t-test. RESULTS: The back pain level was reduced in the experimental group than the control group. The disability of daily living activities was reduced in the experimental group than in the control group. CONCLUSION: Moxibustion was considered to be likely useful therapeutic method for effects of chronic back pain and disability of daily living activities in aged.

Peripheral nerve field stimulation for the management of localized chronic intractable back pain: results from a randomized controlled study.

OBJECTIVES: Improved device technology has caused a renewed interest in peripheral nerve field stimulation (PNfS). This study sought to obtain preliminary estimates of the safety and efficacy of PNfS in patients with localized chronic intractable pain of the back. MATERIALS AND METHODS: This Institutional Review Board-approved, prospective, randomized, controlled, crossover study consisted of two phases. During phase I, patients rotated through four stimulation groups (minimal, subthreshold, low frequency, and standard stimulation). If a 50% reduction in pain was achieved during any of the three active stimulation groups (responder), the patient proceeded to phase II, which began with implant of the permanent system and lasted 52 weeks. The primary endpoint was a reduction in pain, assessed by the visual analog scale (VAS). Analysis of variance, including the effects of patient, treatment, and study period, was used for phase I results. Phase II results were analyzed by paired t-tests. RESULTS: A total of 44 patients were enrolled at five sites. Of these patients, 32 were implanted with a trial system and 30 completed phase I. During phase I, there were significant differences in mean VAS scores between minimal stimulation and subthreshold stimulation (p = 0.003), low frequency stimulation (p < 0.001), and standard stimulation (p < 0.001). Twenty-four patients were classified as responders to the therapy, and 23 patients received permanent system placement. Significant differences in VAS scores were observed between baseline and all follow-up visits during phase II (p < 0.001) CONCLUSIONS: The results provide evidence to support safety and effectiveness of PNfS as an aid in the management of chronic, localized back pain.