Economic evaluation of spinal cord stimulation for chronic reflex sympathetic dystrophy

OBJECTIVE: To evaluate the economic aspects of treatment of chronic reflex sympathetic dystrophy (RSD) with spinal cord stimulation (SCS), using outcomes and costs of care before and after the start of treatment. METHODS: Fifty-four patients with chronic RSD were randomized to receive either SCS together with physical therapy (SCS+PT; n = 36) or physical therapy alone (PT; n = 18). Twenty-four SCS+PT patients responded positively to trial stimulation and underwent SCS implantation. During 12 months of follow-up, costs (routine RSD costs, SCS costs, out-of-pocket costs) and effects (pain relief by visual analogue scale, health-related quality of life [HRQL] improvement by EQ-5D) were assessed in both groups. Analyses were carried out up to 1 year and up to the expected time of death. RESULTS: SCS was both more effective and less costly than the standard treatment protocol. As a result of high initial costs of SCS, in the first year, the treatment per patient is $4,000 more than control therapy. However, in the lifetime analysis, SCS per patient is $60,000 cheaper than control therapy. In addition, at 12 months, SCS resulted in pain relief (SCS+PT [-2.7] vs PT [0.4] [p < 0.001]) and improved HRQL (SCS+PT [0.22] vs PT [0.03] [p = 0.004]). CONCLUSIONS: The authors found SCS to be both more effective and less expensive as compared with the standard treatment protocol for chronic RSD.     

Neurostimulation in patients with chronic neuropathic pain in the so-called failed back surgery syndrome (world and the author's experience)

The failed back surgery syndrome (FBSS) is defined as protracted or recurrent pain, mainly in the lower back and/or legs, even after previous anatomically successful spinal surgery. Treatment of such patients commonly involves difficulties since neither medical therapy nor repeated back surgery does not result in adequate pain relief. Spinal cord stimulation (SCS) is a minimally invasive procedure that allows physicians and patients to define the effect of therapy just before permanent implantation. Both trial stimulation and permanent implantation are fully reversible. Early treatment with SCS has been shown to be very effective in correctly selected FBSS patients and therefore this procedure should be preferred over back resurgery. Clinical studies have demonstrated that CSC provides a sustained, long-term, 50% or more pain relief in over 60% of the patients and makes it possible to reduce the use of analgesics and to improve quality of life and functional status, thus permit many patients to resume work. Many patients told about fair therapeutic effects and the occurrence of mild side effects. Thus, SCS is an accessible alternative to traditional therapy. It is the treatment of choice in drug-resistant FBSS patients where recurrent neuropathic pin persists after surgery and analgesics are no longer effective.     

Spinal cord stimulation for failed back surgery syndrome--does it work and is it cost-effective?

This Practice Point commentary discusses a study by Manca et al. that aimed to investigate the health-related quality-of-life and cost implications of spinal cord stimulation (SCS) plus nonsurgical conventional medical management (CMM) versus nonsurgical CMM alone. Manca et al. reported that the mean total 6-month health-care cost in the SCS group was significantly higher than that in the CMM alone group. However, the gain in health-related quality of life for patients undergoing SCS was significantly greater than that for patients undergoing CMM alone over this same period. In addition, patients in the SCS group used fewer analgesics and nondrug pain treatments (e.g. physical therapy), thus offsetting the upfront costs of SCS by 15%. The relevance of this study in providing an evaluation of health-care expenditures directed at treating low back pain relative to actual treatment outcomes is discussed.     

Evaluation of Sagittal Spinopelvic Balance in Spinal Cord Stimulator Patients

ObjectiveSpinal cord stimulation (SCS) has become a popular nonopioid pain intervention. However, the treatment failure rate for SCS remains significantly high and many of these patients have poor sagittal spinopelvic balance, which has been found to correlate with increased pain and decreased quality of life. The purpose of this study was to determine if poor sagittal alignment is correlated with SCS treatment failure.Materials and MethodsComparative retrospective analysis was performed between two cohorts of patients who had undergone SCS placement, those who had either subsequent removal of their SCS system (representing a treatment failure cohort) and those that underwent generator replacement (representing a successful treatment cohort). The electronic medical record was used to collect demographic and surgical characteristics, which included radiographic measurements of lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Also included were data on pain medication usage including opioid and nonopioid therapies.ResultsEighty-one patients met inclusion criteria, 31 had complete removal, and 50 had generator replacements. Measurement of sagittal balance parameters demonstrated that many patients had poor alignment, with 34 outside normal range for LL (10 vs 24 in removal and replacement cohorts, respectively), 30 for PI (12 [38.7%] vs 18 [36.0%]), 46 for PT (18 [58.1%] vs 28 [56.0%]), 38 for SS (18 [58.1%] vs 20 [40.0%]), and 39 for PI-LL mismatch (14 [45.2%] vs 25 [50.0%]). There were no significant differences in sagittal alignment parameters between the two cohorts.ConclusionsThis retrospective cohort analysis of SCS patients did not demonstrate any relationship between poor sagittal alignment and failure of SCS therapy. Further studies of larger databases should be performed to determine how many patients ultimately go on to have additional structural spinal surgery after failure of SCS and whether or not those patients go on to have positive outcomes.     

Future trends in spinal cord stimulation

Spinal cord stimulation (SCS) has been available for about 30 years, but only in the past five years has it met with widespread acceptance and recognition by the medical community. Traditionally performed by neurosurgeons, SCS is being increasingly utilized by anesthesiologists, orthopedic surgeons and physiatrists. Pain management continues to be the most widespread application of SCS. More sophisticated technology has allowed the implanters to successfully address more complex pain syndromes such as widespread reflex sympathetic dystrophy and the failed back syndrome. Other applications are being developed, combining the ability to stimulate the spinal cord, the nerve roots and the peripheral nerves. Examples include angina pectoris, urinary incontinence and occipital neuralgia. Computer-interactive programming is gaining popularity, especially due to the extreme complexity of the implanted stimulation devices. The ability to stimulate independently multiple channels as well as multiple arrays of electrodes is today a reality. This has increased greatly the efficacy, safety and reliability of the modality. In the future, SCS will undoubtedly move several steps up in the treatment ladder of chronic pain conditions, while new applications will be discovered. The future of neural implantable technologies is bright, with an increasingly important role in the medical management of chronic conditions affecting the nervous system.     

Spinal cord stimulation for complex regional pain syndrome: report of 2 cases

Two adolescents with complex regional pain syndrome (CRPS) were treated safely and effectively by spinal cord stimulation (SCS). They complained of intractable pain resistant to conservative therapies. Whereas continuous epidural anesthesia temporarily reduced pain, SCS was more effective in alleviating chronic severe pain and improving the quality of life. With careful selection of patients, SCS therapy might be recommended even in young cases.     

Combined Spinal Cord and Peripheral Nerve Field Stimulation for Persistent Post‐Herniorrhaphy Pain

Objectives: Chronic post‐hernia pain is a common complication after inguinal herniorrhaphies. Peripheral nerve field stimulation (PNFS) and spinal cord stimulation (SCS) are two new promising treatment modalities. Four patients with persistent neuropathic post‐hernia pain were recruited for this prospective study. Materials and Methods: Electrodes were inserted into the epidural space of the spinal canal and into the subcutaneous tissue in the inguinal region during a single surgical procedure. During a 14‐day trial, double‐blind stimulation was performed via an external stimulator: three days using the spinal electrode (SCS), three days using the inguinal electrode (PNFS), three days using both (SCS + PNFS), and five days off, with an alternating order from patient to patient. During the trial, pain intensity was assessed thrice daily by the visual analog scale. Additionally, pain intensity and quality of life (QOL) were assessed before and after surgical intervention by the Brief Pain Inventory, SF36 scale, and Pain Disability Index. Results: All patients had a marked pain reduction during the trial phase, and this reduction was more prominent when both electrodes were activated simultaneously (p < 0.001). At the late follow‐up, a significant pain reduction and improvement of QOL was observed in three patients. Conclusions: Both SCS and PNFS are effective in treating post‐hernia pain, but the magnitude of pain reduction was more prominent with concomitant stimulation. Combined PNFS and SCS should be considered for patients with a less than optimal response to either SCS or PNFS. More studies are necessary to address the cost‐effect issues of this new approach to treatment.     

Future trends in spi al cord stimulation

Abstract

Spinal cord stimulation (SCS) has been available for about 30 years, but only in the past five years has it met with widespread acceptance and recognition by the medical community. Traditionally performed by neurosurgeons, SCS is being increasingly utilized by anesthesiologists, orthopedic surgeons and physiatrists. Pain management continues to be the most widespread application of SCS. More sophisticated technology has allowed the implanters to successfully address more complex pain syndromes such as widespread reflex sympathetic dystrophy and the failed back syndrome. Other applications are being developed, combining the ability to stimulate the spinal cord, the nerve roots and the peripheral nerves. Examples include angina pectoris, urinary incontinence and occipital neuralgia. Computer-interactive programming is gaining popularity, especially due to the extreme complexity of the implanted stimulation devices. The ability to stimulate independently multiple channels as well as multiple arrays of electrodes is today a reality. This has increased greatly the efficacy, safety and reliability of the modality. In the future, SCS will undoubtedly move several steps up in the treatment ladder of chronic pain conditions, while new applications will be discovered. The future of neural implantable technologies is bright, with an increasingly important role in the medical management of chronic conditions affecting the nervous system. [Neurol Res 2000; 22: 279-284]     

Treatment of Multifocal Pain with Spinal Cord Stimulation

Introduction: We report a retrospective case study of combined treatment of cancer‐related pain and chronic low back and lower extremity pain related to postlaminectomy syndrome (PLS) with one spinal cord stimulation (SCS) system. Methods: The patient underwent an uneventful SCS trial with percutaneous placement of two temporary eight‐electrode leads (Medtronic Inc., Minneapolis, MN) placed at the level of T8‐T9‐T10 and T5‐T6‐T7. Results: After successful trial, he was implanted with permanent leads and generator, reporting sustained pain relief at 12‐month follow‐up visit. Discussion: SCS is a trialable, reversible, and interactive therapy permitting patients to control the level of stimulation they feel based on their degree of pain. Conclusion: SCS provides an effective, alternative treatment for select patients with cancer‐related chest wall pain and pain related to PLS who have failed conservative treatment.     

Dual Spinal Cord Stimulation for Complex Pain: Preliminary Study

Objectives To retrospectively analyze by indices of success, patients with chronic complex pain, including, axial low back pain, receiving dual spinal cord stimulation (SCS) systems. Methods Eighteen patients with dual spinal cord stimulators have been retrospectively and nonrandomly analyzed. The preponderance of patients in our study group had failed back surgery syndrome (FBSS). Parameters of success of our therapy included reduction of medication, if any, complications, if any, and satisfaction with therapy and improvement in the quality of life, measured by a visual analogical scale (VAS) from 0 to 10. Patients were asked to rate their overall experience with their SCS systems and were divided into four separate groupings according to their overall rating of their therapy. These four groupings included therapy ratings of excellent (70–100%), good (> 50%), fair (< 50%), and poor (< 30%). Satisfaction with therapy and improvement in quality of life were evaluated on a five‐point scale. Patients were asked to rate changes in their quality of life after therapy using the following normative scale: much better, better, no change, worse, and much worse. All the patients in our study were asked if they would repeat their therapy with dual spinal cord stimulation. Results Paresthesia coverage, overlapping the reported painful region, was obtained in 80% of the patients in our study. The VAS decreased an average of 5.6 (range 2–10) after 6 months and 4.9 (range 2–8) at the end of the study. Six patients (37.5%) reported excellent results; four patients (25%) reported good; three (18.7%), fair and poor. Seventy percent of the patients were satisfied with the treatment and reported an increase in their quality of life. Medications were reduced in 75% of the patients. Thirteen (81%) patients with dual lead SCS therapy were willing to repeat the SCS implant procedure. Complications occurred in 43.7%. Conclusions Dual spinal cord stimulation is appropriate and efficacious for treating complex pathology and complex pain that including pain of the low, axial back.     

Spinal Cord Stimulation in Complex Regional Pain Syndrome Type I of Less Than 12‐Month Duration

Introduction: Complex regional pain syndrome type 1 (CRPS‐1) has a 31% probability of becoming chronic. The early use of spinal cord stimulation (SCS) has been recommended as a strategy to prevent chronicity and functional impairment. Methods: In a prospective study, we treated 74 CRPS‐1 patients with a mean disease duration of 17 weeks with standard therapy consisting of physical therapy, topical dimethyl sulfoxide, analgesics, transcutaneous stimulation, and sympathetic blockade. Patients who did not respond to standard therapy were offered a treatment with SCS. In these patients, we investigated the impact on pain, quality of life, and function. Results: Out of these 74 patients treated with standard therapy, six patients were included for early SCS treatment. The overall mean pain relief after one year was 35%. The mental component of the Short Form 36 improved; however, there was no effect on the physical component. None of the SCS treated patients showed a clear improvement in functional outcome. Discussion: We conclude that the feasibility of performing a randomized controlled trial on early SCS therapy in CRPS‐1 is low because of the good disease improvement with standard therapy in the first year after onset. This study raises questions about the need to use SCS early in the course of CRPS‐1 because of the probable lack of additional benefit compared with SCS in chronic CRPS‐1.     

Spinal Cord Stimulation With Hybrid Lead Relieves Pain in Low Back and Legs

Objective: The failed back surgery syndrome (FBSS) is the most common chronic pain syndrome. Whereas it is relatively easy to achieve pain relief in the lower limbs of FBSS patients with spinal cord stimulation (SCS), it is difficult to manage low back pain with SCS. The performance of a paddle‐shaped SCS lead that can be inserted surgically as well as percutaneously (a hybrid lead) was evaluated in a prospective study on the relief of low back pain and leg pain in patients with FBSS. Materials and Methods: Patients with FBSS being eligible for SCS were enrolled in the study, and a hybrid lead was placed surgically. Outcome measures included pain scores for low back and leg pain assessed by visual analog scale (VAS), pain medication, and patient satisfaction. These scores were assessed before and at regular intervals after implantation. Results: It was shown that a single hybrid lead, generally positioned over the physiological midline of the spinal cord, is capable of alleviating both low back and leg pain in patients with FBSS. Forty‐five subjects were eligible for SCS and received trial stimulation. Forty‐two of them had a successful trial period and were converted to a permanent system. Their average VAS score at baseline was 8.0 for lower limb pain and 7.5 for low back pain. After six months of SCS, these average VAS scores were reduced to 3.2 and 3.5, respectively, and also pain medication was reduced significantly. Conclusion: SCS with a hybrid lead in subjects with FBSS is safe, and causes significant pain relief in both the low back and the lower limbs.     

Spinal Cord Stimulation for Pain Management in Ankylosing Spondylitis: A Case Report

Introduction. The classic presentation of ankylosing spondylitis not only impairs spinal mobility but also imposes functional limitations, and fatigue is common. Methods. We report here the outcomes of spinal cord stimulation (SCS) in the case of a 47‐year‐old man with low back and hip/thigh pain due to ankylosing spondylitis, with failed responses to conservative therapies aimed at treating this pain. Results. Spinal cord stimulation induced axial low back and bilateral hip paresthesia resulting in complete subjective pain relief, cessation of analgesic medications, reduced fatigue, and improved sleep patterns. SCS also resulted in improved socioeconomic outcomes with a return to work. Conclusions. With further research in patients with broader presentations of the disease, SCS may prove efficacious in suppressing intractable pain symptoms due to ankylosing spondylitis, thus improving quality of life measures.     

Spinal Cord Stimulation Has Comparable Efficacy in Common Pain Etiologies

Objectives. The probability of success with spinal cord stimulation (SCS) depends largely on appropriate patient selection. Here, we have assessed the predictive value of pain etiology as it relates to pain relief with SCS as part of a prospective multicenter clinical trial. Methods. Sixty‐five subjects with chronic and intractable pain tested an epidural SCS system. Subjects reported pain ratings (visual analog scale) with stimulation off and stimulation on at scheduled follow‐up visits for up to 18 months after activation of the system. Visual analog scale scores were averaged and stratified by dominant pain etiologies, comprising failed back surgery syndrome, complex regional pain syndrome, and a subgroup of subjects with miscellaneous other pain etiologies. Results. More than 70% of subjects in each subgroup had successful outcomes during the temporary trial period and similar percentages of subjects from each etiology subgroup subsequently went on to permanent implantation. After permanent implantation, all subgroups reported more than 50% pain relief, on average, at each follow‐up time point. No predictive value of pain etiology was observed. Conclusions. Spinal cord stimulation is an effective therapy for neuropathic pain arising from a variety of causes. Failed back surgery syndrome, complex regional pain syndrome, and pain of other etiologies responded equally well to SCS.     

Reflex sympathetic dystrophy. A review

Reflex sympathetic dystrophy is a syndrome of burning pain, hyperesthesia, swelling, hyperhidrosis, and trophic changes in the skin and bone of the affected extremity. It is precipitated by a wide variety of factors in addition to nerve injury. It occurs outside of dermatomal distributions and can spread to involve other extremities without new injury. The diagnosis is primarily clinical, but roentgenography, scintigraphy, and sympathetic blockade can help to confirm the diagnosis. The most successful therapies are directed toward blocking the sympathetic innervation to the affected extremity, in conjunction with physical therapy. The theories proposed to explain the pathophysiology of reflex sympathetic dystrophy include "reverberating circuits" in the spinal cord that are triggered by intense pain, ephaptic transmission between sympathetic efferents and sensory afferents, and the presence of ectopic pacemakers in an injured nerve.     

Physiology of Spinal Cord Stimulation: Review and Update

Spinal cord stimulation (SCS) was an outgrowth of the well-known gate control theory presented by Melzack and Wall in 1965. Although the method has been used to treat chronic severe pain for more than three decades, very little was known about the physiological and biochemical mechanisms behind the beneficial effects until recently. We now know that SCS activates several different mechanisms to treat different types of pain such as neuropathic and ischemic. In general, these mechanisms seem most dependent on activation of only a few segments of the spinal cord. However, both animal studies and human observations have indicated that supraspinal circuits may contribute as well. In the treatment of neuropathic pain, intermittent SCS may give several hours of pain relief after cessation of the stimulation. This protracted effect indicates long-lasting modulation of neural activity involving changes in the local transmitter systems in the dorsal horns. In ischemic pain, animal experiments demonstrate that inhibition of afferent activity in the spinothalamic tracts, long-term suppression of sympathetic activity, and antidromic effects on peripheral reflex circuits may take part in the pain alleviation. Moderate SCS intensities seem to evoke sympathetic inhibition, but higher stimulation intensities may induce antidromically mediated release of vasoactive substances, eg, the calcitonin gene-related peptide (CGRP), resulting in peripheral vasodilation. The anti-ischemic effect of SCS in angina pectoris due to intermittent coronary ischemia probably occurs because application of SCS appears to result in a redistribution of cardiac blood supply, as well as a decrease in tissue oxygen demand. Recent studies indicate that SCS modulates the activity of cardiac intrinsic neurons thereby restricting the arrythmogenic consequences of intermittent local coronary ischemia. The present state of knowledge is briefly reviewed and recent research directions outlined.     

Effect of stimulation of the spinal cord on phasic and tonic reflexes in patients with central motor neuron damage

Spinal cord stimulation (SCS) is a method enabling the control of increased muscle tonus to be achieved in various spinal cord injuries. Polyelectromyographic (PEMG) methods were used for neurophysiological assessment of the degree of cord damage and persistent spinal reflexes as well as supramedullary influences. The analysed material comprised 40 PEMG records in 19 patients with spastic paraparesis or paraplegia after cord injury, cord tumour or multiple sclerosis. In 15 cases tentative epidural cord stimulation was done and 11 patients received implantation of a system for long-term stimulation. In most cases the epidural electrodes were implanted below the damaged segment, usually in the thoracic part of the cord. Before and after SCS beginning PEMG was done with a 16-channel Mingograph Siemens Elema with simultaneous recording of the responses from the symmetric muscles: quadriceps, semitendinous, adductor femoris, anterior tibialis and triceps surae. The effect of SCS was analysed on exteroceptive and proprioceptive reactions during testing of knee and ankle reflexes, and on the response of the muscles to vibration. In most patients a reduction was observed of the intensity of tendon reflexes, particularly the spread of the reflex to the contralateral extremity was no longer seen. The vibration reflex had a tonic character persisting in 48% of the studied muscles, even in patients with clinically complete transsection of the cord. The change of the character of monosynaptic reflexes and the presence of the vibration reflex suggest that SCS modifies the proprioceptive segmental spinal reactions.     

Spinal Cord Stimulation for Pain Treatment After Spinal Cord Injury

In addition to restoration of bladder, bowel, and motor functions, alleviating the accompanying debilitating pain is equally important for improving the quality of life of patients with spinal cord injury(SCI). Currently,however, the treatment of chronic pain after SCI remains a largely unmet need. Electrical spinal cord stimulation(SCS) has been used to manage a variety of chronic pain conditions that are refractory to pharmacotherapy. Yet, its efficacy, benefit profiles, and mechanisms of action in SCI pain remain elusive, due to limited research, methodological weaknesses in previous clinical studies, and a lack of mechanistic exploration of SCS for SCI pain control. We aim to review recent studies and outline the therapeutic potential of different SCS paradigms for traumatic SCI pain. We begin with an overview of its manifestations,classification, potential underlying etiology, and currentchallenges for its treatment. The clinical evidence for using SCS in SCI pain is then reviewed. Finally, future perspectives of pre-clinical research and clinical study of SCS for SCI pain treatment are discussed.     

Physical Therapy Considerations and Recommendations for Patients Following Spinal Cord Stimulator Implant Surgery

ObjectivesSpinal cord stimulation (SCS) is an established therapy option in interventional pain medicine. Recent advances in technology have allowed for greater compliance with treatment and improved efficacy in pain control. This article was proposed to fill the gap in the literature addressing this specific patient population and to facilitate further research. Even though there is a lack of consensus among societies and experts on exact parameters of physical therapy (PT) considerations and postoperative limitations in patients with SCS, we propose rehabilitative care for this population should be standardized. As the number of patients with SCS implants grow, it is vital to understand how to appropriately approach patients with implantable devices when additional treatments such as PT are prescribed.Materials and MethodsA literature search was performed on the use of PT following SCS implantation. Presently, there is no literature to date which addresses the use of PT in this patient population. The lack of data is the largest hurdle in the creation of formal SCS therapy guidelines. The authors therefore proposed recommendations for rehabilitation based upon a detailed understanding of SCS hardware alongside well-studied physiotherapy concepts.ResultsConsiderations when initiating PT in the SCS patient population should include: 1) biomechanics and quality of SCS output; 2) therapeutic exercise and spinal manipulation in association with risk for lead migration and fracture; 3) the application of therapeutic modalities and risk for injury to the patient and/or damage to the SCS componentry; and 4) integration of a biopsychosocial, person-centered approach.ConclusionsPT treatment protocol in patients with a recently implanted SCS device should be person-centered addressing individual needs, values, and goals. Further research is needed to fully appreciate the impact of an interprofessional approach to management of SCS patients, particularly following stimulator implantation.     

Spinal Cord Stimulation With Additional Peripheral Nerve/Field Stimulation Versus Spinal Cord Stimulation Alone on Back Pain and Quality of Life in Patients With Persistent Spinal Pain Syndrome

IntroductionPersistent spinal pain syndrome (PSPS) or failed back surgery syndrome (FBSS) refers to new or persistent pain following spinal surgery for back or leg pain in a subset of patients. Spinal cord stimulation (SCS) is a neuromodulation technique that can be considered in patients with predominant leg pain refractory to conservative treatment. Patients with predominant low back pain benefit less from SCS. Another neuromodulation technique for treatment of chronic low back pain is subcutaneous stimulation or peripheral nerve field stimulation (PNFS). We investigated the effect of SCS with additional PNFS on pain and quality of life of patients with PSPS compared with that of SCS alone after 12 months.Materials and MethodsThis is a comparative study of patients with PSPS who responded to treatment with either SCS + PNFS or SCS only following a multicenter randomized clinical trial protocol. In total, 75 patients completed the 12-month follow-up: 21 in the SCS-only group and 54 in the SCS + PNFS group. Outcome measures were pain (visual analog scale), quality of life (36-Item Short Form Survey [SF-36]), anxiety and depression (Hospital Anxiety and Depression Scale [HADS]), overall health (EuroQol Five-Dimension [EQ-5D]), disability (Oswestry Disability Index [ODI]), and pain assessed by the McGill questionnaire.ResultsThere were no significant differences in baseline characteristics between the two groups. Both groups showed a significant reduction in back and leg pain at 12 months compared with baseline measurements. No significant differences were found between the groups in effect on both primary (pain) and secondary parameters (SF-36, HADS, EQ-5D, ODI, and McGill pain).ConclusionIn a subgroup of patients with chronic back and leg pain, SCS alone provided similar long-term pain relief and quality-of-life improvement as PNFS in addition to SCS. In patients with refractory low back pain not responding to SCS alone, adding PNFS should be recommended.Clinical Trial RegistrationThe Clinicaltrials.gov registration number for the study is NCT01776749.