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Objectives Due to the impact of COVID‐19 epidemic, face‐to‐face follow‐up treatments for patients with chronic pain and implanted spinal cord stimulation (SCS) devices are forced to be delayed or stopped. This has led to more follow ups being done remotely. Meanwhile, with the development of 4G/5G networks, smartphones, and novel devices, remote programming has become possible. Here, we investigated the demand and utility of remote follow‐ups including remote programming for SCS for patients with chronic pain. Materials and Methods A questionnaire including questions on demographic characteristics, pain history, postimplantation life quality, standard follow‐up experience, remote follow‐up, and remote programming experience was sent to patients diagnosed as chronic intractable pain and treated with SCS during January 2019 to January 2020. Results A total of 64 participants completed the questionnaire. About 70% of participants expressed demands for remote follow‐ups due to the inconvenience, high costs, and time consumption of traditional follow‐up visits. Nearly 97% of participants have attempted remote follow‐ups, and about 81% of participants have further tried remote programming. Approximately, 96% of them recognized the benefits. Conclusions The remote programming was in high demand among participants. Most of the participants have tried remote follow‐ups or even remote programming. The remote programming appeared to be more efficient, economic and were widely recognized among participants.

Initial clinical studies have shown that the stimulation of the dorsal root ganglion (DRG) can significantly reduce chronic intractable pain. However, clinical data on long-term results and complications of these systems are limited. The aim of this prospective study is to report on a single center long-term follow-up of DRG stimulation for intractable chronic pain. Participants were implanted with DRG stimulation devices between 2013 and 2015 with an observation period of 24 months. Patients were contacted again in 2020 for a final follow-up (ie, between 5 and 7 years postimplantation). Forty-two participants were recruited, of whom 32 received the fully implantable pulse generator (IPG). At the final follow-up, 50% (16/32) of participants were still using DRG stimulation. Two participants still had the original IPG and 14 had received a replacement IPG. Pain scores were significantly reduced at 24 months, mean difference 1.7 (95% confidence interval: 0.2-3.3, P = 0.03), and at the last follow-up, mean difference 2.1 (95% confidence interval: 0.3-4, P = 0.03). Significant improvements were observed for health-related quality of life. The findings were generally robust to imputation methods of missing data. Implantable pulse generators of 8 patients were explanted because of dissatisfaction with pain relief. In conclusion, DRG stimulation can provide effective pain relief and improved quality of life in patients suffering with neuropathic pain, although this study had a revision rate of 42% within the first 24 months, and 56% of IPGs that were replaced because of battery depletion had a shorter than expected battery life.

Chronic intractable pain affects a significant percentage of the worldwide population, and it is one of the most disabling and expensive health conditions across the globe. Spinal cord stimulation (SCS) has been used to treat chronic pain for a number of years, but high-frequency SCS was not the US FDA approved until 2015. In this review, we describe the history and development of high-frequency SCS and discuss the benefits of the Omnia™ implantable pulse generator. We also provide a thorough literature review of the published work, highlighting the efficacy and safety profiles of high-frequency SCS for the treatment of multiple chronic pain conditions. Lastly, we offer our outlook on future developments with the Omnia SCS system.

As COVID-19 rampages throughout the world and has a major impact on the healthcare system, non-emergency medical procedures have nearly come to a halt due to appropriate resource reallocation. However, pain never stops, particularly for patients with chronic intractable pain and implanted spinal cord stimulation (SCS) devices. The isolation required to fight this pandemic makes it impossible for such patients to adjust the parameters or configuration of the device on site. Although telemedicine has shown a great effect in many healthcare scenarios, there have been fewer applications of such technology focusing on the interaction with implanted devices. Here, we introduce the first remote and wireless programming system that enables healthcare providers to perform video-based real-time programming and palliative medicine for pain patients with a SCS implant. During the COVID-19 pandemic from January 23, 2020, the date of lockdown of Wuhan, to April 30, 2020, 34 sessions of remote programming were conducted with 16 patients. Thirteen of the 16 patients required programming for parameter optimization. Improvement was achieved with programming adjustment in 12 of 13 (92.3%) cases. Eleven of the 16 (68.8%) patients reported that the system was user-friendly and met their needs. Five patients complained of an unstable connection resulting from the low network speed initially, and three of these patients solved this problem. In summary, we demonstrated that a remote wireless programming system can deliver safe and effective programming operations of implantable SCS device, thereby providing palliative care of value to the most vulnerable chronic pain patients during a pandemic. Clinical Trial Registration www.clinicaltrials.gov, identifier NCT 03858790.

Background: Spinal cord stimulation (SCS) has emerged as state-of-the-art evidence-based treatment for chronic intractable pain related to spinal and peripheral nerve disorders. Traditionally delivered as steady-state, paraesthesia-producing electrical stimulation, newer technology has augmented the SCS option and outcome in the last decade. Objective: To present an overview of the traditional and newer SCS waveforms. Materials and Methods: We present a short literature review of SCS waveforms in reference to newer waveforms and describing paraesthesia-free, high frequency, and burst stimulation methods as well as advances in waveform paradigms and programming modalities. Pertinent literature was reviewed, especially in the context of evolution in the waveforms of SCS and stimulation parameters. Results: Conventional tonic SCS remains one of the most utilized and clinically validated SCS waveforms. Newer waveforms such as burst stimulation, high-frequency stimulation, and the sub-perception SCS have emerged in the last decades with favorable results with no or minimal paraesthesia, including in cases otherwise intractable to conventional tonic SCS. The recent evolution and experience of closed-loop SCS is promising and appealing. The experience and validation of the newer SCS waveforms, however, remain limited but optimistic. Conclusions: Advances in SCS device technology and waveforms have improved patient outcomes, leading to its increased utilization of SCS for chronic pain. These improvements and the development of closed-loop SCS have been increasingly promising development and foster a clinical translation of improved pain relief as the years of research and clinical study beyond conventional SCS waveform come to fruition.

Background Although effective results of many studies support the use of spinal cord stimulation in chronic pain patients, no randomized controlled trial has been undertaken in China to date. CITRIP is a multicenter, prospective, randomized, withdrawal study designed to evaluate the clinical effectiveness and safety of spinal cord stimulation plus remote programming management in patients with intractable trunk or limb pain. Method Participants will be recruited in approximately 10 centers across China. Eligible participants with intractable trunk or limb and an average visual analog scale (VAS) score ≥ 5 will undergo a spinal cord stimulation test. Participants with VAS score reduction ≥ 50% could move forward to receive implantation of an implanted pulse generator. In the withdrawal period at 3-month follow-up visit, participants randomized to the experimental group (EG) will undergo continuous stimulation while ceasing the stimulation in the control group (CG). The outcome assessment will occur at baseline and at 1, 3 (pre- and post-randomization), and 6 months. The primary outcome is the difference of maximal VAS score between EG and CG in the withdrawal period compared with baseline before the withdrawal period. Additional outcomes include VAS score change at 1-, 3-, and 6-month follow-ups; responder rate (VAS score improving by 50%); achievement rate of a desirable pain state (VAS score ≤ 4); awake times during sleep; Beck Depression Inventory for depression evaluation; short-form 36 for quality of life evaluation; drug usage; and satisfaction rating of the device. Adverse events will be collected. The primary analysis will follow the intention-to-treat principle. Discussion The CITRIP study seeks to evaluate the effectiveness and safety of a randomized withdrawal trial of spinal cord stimulation for patients with intractable trunk or limb pain. Trial registration ClinicalTrials.gov NCT03858790. Registered on March 1, 2019, retrospectively registered

Chronic pain is consistently listed as one of the most costly and disabling health problems worldwide. In an effort to treat these suffering individuals, significant amounts of time and energy have been devoted to discover safe and effective pain relieving treatments. Dorsal root ganglion stimulation is the newest treatment modality to be created for chronic intractable pain. In this manuscript, we review the history and development, published research and safety profile of the Proclaim™ DRG Neurostimulator System (Abbott, TX, USA). At last, we offer our outlook on future developments with dorsal root ganglion stimulation.

Background Spinal cord stimulation (SCS) is an effective treatment option to relieve chronic intractable pain, and failed back surgery syndrome (FBSS) is a key indication. Objectives The objective of the current study was to analyze the cost consequences of using non-rechargeable (NR)-SCS and rechargeable (R)-SCS. Methods Real data taken from a review of 86 patients were used to simulate costs and review which patients might have benefitted more from R-SCS. Calculations were made to see what is the impact from a monetary point of view. Results On average, NR-SCS devices lasted for 58 months (M). Only 14 patients were not eligible to receive an R-SCS implant. We found that using R-SCS batteries would save up to €56.322 on average over a patient's life expectancy, which means a saving of 43% compared to using NR-SCS systems. In our analysis, we found that if R-SCS implants were used instead of NR-SCS batteries, a saving of €5,735,334.23 over patients' life expectancy would be made, which represented a 63% saving to the public health system. We found that R-SCS was cost-beneficial from second year compared to NR-SCS, saving up to 70% when patients are implanted for 9 years. Conclusions This cost-consequences analysis suggests that R-SCS implants are more cost-beneficial than NR-SCS systems in well-selected patient candidates for this type of treatment.

Although spinal cord stimulation (SCS) is a useful treatment for chronic intractable pain, the optimal method of stimulation has not yet been established. In this prospective, crossover study, we compared the efficacy of using a constant current (CC) system with that of a constant voltage (CV) system for temporal SCS. Twenty patients were enrolled and divided into two groups. For 10 patients, a CV system was applied on Days 1-5, followed by the use of a CC system on Days 6-10. For the other 10 patients, a CC system was applied for the first five days, followed by a CV system for the subsequent five days. We evaluated the alteration of pain intensity using a visual analogue scale (VAS), the area of stimulation, the stability of effect, and patient satisfaction regarding treatment. The pain scores decreased significantly after the start of the SCS. There was no significant difference in the change in VAS between the two systems. The stimulation method used for temporal SCS did not affect the reduction of pain intensity. Patients felt a wider stimulation area by the CC system compared to the CV system.

Item does not contain fulltext Implantable motor cortex stimulation (iMCS) has been performed for >25 years to treat various intractable pain syndromes. Its effectiveness is highly variable and, although various studies revealed predictive variables, none of these were found repeatedly. This study uses neural network analysis (NNA) to identify predictive factors of iMCS treatment for intractable pain. A systematic review provided a database of patient data on an individual level of patients who underwent iMCS to treat refractory pain between 1991 and 2017. Responders were defined as patients with a pain relief of >40% as measured by a numerical rating scale (NRS) score. NNA was carried out to predict the outcome of iMCS and to identify predictive factors that impacted the outcome of iMCS. The outcome prediction value of the NNA was expressed as the mean accuracy, sensitivity, and specificity. The NNA furthermore provided the mean weight of predictive variables, which shows the impact of the predictive variable on the prediction. The mean weight was converted into the mean relative influence (M), a value that varies between 0 and 100%. A total of 358 patients were included (202 males [56.4%]; mean age, 54.2 +/-13.3 years), 201 of whom were responders to iMCS. NNA had a mean accuracy of 66.3% and a sensitivity and specificity of 69.8% and 69.4%, respectively. NNA further identified 6 predictive variables that had a relatively high M: 1) the sex of the patient (M=19.7%); 2) the origin of the lesion (M=15.1%); 3) the preoperative numerical rating scale score (M=9.2%); 4) preoperative use of repetitive transcranial magnetic stimulation (M=7.3%); 5) preoperative intake of opioids (M=7.1%); and 6) the follow-up period (M=13.1%). The results from the present study show that these 6 predictive variables influence the outcome of iMCS and that, based on these variables, a fair prediction model can be built to predict outcome after iMCS surgery. PERSPECTIVE: The presented NNA analyzed the functioning of computational models and modeled nonlinear statistical data. Based on this NNA, 6 predictive variables were identified that are suggested to be of importance in the improvement of future iMCS to treat chronic pain.

To use biomarkers to gain insight into and gauge the residual (post-treatment) level of inflammation in two groups of intensively treated patients with severe chronic pain.Three study groups were analyzed, and included: (i) patients (n = 90) with chronic intractable pain (CIP), (ii) patients (n = 26) with chronic pain and MRI-documented arachnoiditis (ARC) and (iii) normal subjects without a diagnosis of chronic pain (n = 86). We determined and compared the serum concentrations of Alpha-1 Antitrypsin (A1AT), Myeloperoxidase (MPO) and soluble Tumor Necrosis Factor receptor type 2 (sTNFR2) in each of the patient populations studied.Patients treated for ARC or CIP had higher serum levels of A1AT and MPO than normal untreated subjects without a diagnosis of chronic pain. ARC patients had an A1AT mean serum concentration of 167.9 ± 41.9 mg/dL as compared to 148.9 ± 35.2 mg/dL for normal subjects (p = 0.023). CIP patients had the highest mean serum A1AT level 183.6 ± 39.2 mg/dL with p values of0.0001 or 0.08 when compared to normal subjects or ARC patients respectively. ARC patients had an MPO mean serum concentration of 344.6 ± 227.9 ng/mL as compared to 188.2 ± 107.5 ng/mL for normal subjects (p = 0.0001). CIP patients had a similar mean serum MPO level of 352.3 ± 164 ng/mL with p values of0.0001 or 0.85 when compared to normal subjects or ARC patients respectively. In addition, we noted a difference in the pattern of MPO expression in patients with ARC in that 34% had levels of MPO at normal or below and 31% had levels 2-fold or greater than normal.This data supports the concept that in centralized pain, sites of neuroinflammation elaborate MPO and other inflammatory factors which may not be completely cleared from the system despite extensive and complex treatment regimens.

Although chronic pain is one of the most important medical problems facing society, there has been very limited progress in the development of novel therapies for this condition. Here, we discuss high-impact research priorities to reduce the number of people transitioning from acute to chronic intractable pain.

当科ではpatient-controlled analgesia（PCA）用ポンプを用いて術後急性期の疼痛管理を行い，成果をあげてきた．今回,内科より難治性慢性疼痛を有する患者の疼痛管理を依頼された．フェンタニルを用いた静脈内PCAを開始し，維持輸液の速度，点滴路の長さ（容積）など投与経路を考慮し，PCAの接続部位を患者側に最も近くした結果，鎮痛効果が増し，副作用が減少し，患者満足度が向上した．静脈内PCAを行っている患者の疼痛管理が不十分な場合には，薬液が体内に入るまでの経路を検討することが重要である．

Objectives Spinal cord stimulation (SCS) is an effective method of relieving chronic intractable pain, and one of its key indications is failed back surgery syndrome (FBSS). The objective of the current study was to evaluate the cost effectiveness of 10 kHz high-frequency SCS (HF10 SCS) compared to conventional medical management (CMM), reoperation, and traditional nonrechargeable (TNR-SCS) and rechargeable SCS (TR-SCS). Methods A health economic model of SCS in the United Kingdom was reproduced in the perspective of the health care system to simulate costs and quality adjusted life years (QALYs) over 15 years. In the model, both a decision tree and the Markov model were used to describe the health outcomes of the evaluated therapies. Results HF10 SCS therapy showed a favorable incremental cost-effectiveness ratio (ICER) of £3,153 per QALY gained as compared to CMM and established dominance (less costly, more QALYs) compared to TNR-SCS (£8,802 per QALY vs. CMM) and TR-SCS (£5,101 per QALY vs. CMM). Conclusion This first analysis of the cost effectiveness of HF10 SCS suggests that it is more cost effective and provides a greater number of QALYs than both TNR-SCS and TR-SCS.

The history, theory, and methods of modern radiofrequency lesioning are reviewed.Various considerations are advanced including suggestion of inclusion and exclusion criteria for treatment, methods of ensuring accuracy of radiofrequency lesioning, and potential side effects of radiofrequency lesioning.The authors also review the reasons why lesioning may be ineffective for some patients. Chronic pain syndromes that may benefit from treatment with radiofrequency neurolysis are specified, as are the radiofrequency techniques commonly used to treat these syndromes.The authors conclude that radiofrequency neurolysis is a highly specialized intervention that shows promise for treatment of chronic intractable pain among properly selected patients who participate in multidisciplinary treatment programs and who have failed conservative therapies. It is emphasized that the practitioner must be skilled in the exercise of proper fluoroscopic technique in order to perform accurate radiofrequency lesioning.

Lower back pain (LBP) is a common condition with profound economic and social consequences. A conservative, symptomatic, goal-oriented management program is advocated by most, emphasizing pain relief and restoration of functional capacity. Still, LBP is recurrent in approximately 50% of patients and up to 5-10% experience chronic intractable pain. This article describes how to evaluate and rehabilitate the patient with spinal impairment (SI). All is summarized in a diagnostic/treatment algorithm as used in the spine rehabilitation center. Causes of LBP, components of the patient history and physical, diagnostic test usage and management options are summarized in tables for future reference. Lastly, preventative measures are discussed which, when implemented within a treatment program, may prevent future reoccurrences.

Copyright: © 2013 Zhou L, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Neurostimulation has been used for several decades and become increasingly popular for treatment of chronic intractable pain. Following is introducing the principles of spinal cord stimulation (SCS) and peripheral nerve stimulation (PNS).

Spinal cord stimulation (SCS) became available in the 1970s as a treatment option for patients with constant or recurring pain. This invasive procedure is performed after all other efforts have failed to prove effective in controlling pain. Advanced technology enables the patient to perform adjustments to maximize comfort with the use of a magnet or portable programmer. Nursing care is guided by a specific plan of care for the SCS patient population. A patient population-specific standard may be useful.

Fifteen patients with intractable pain received intrathecal morphine delivered via a programmable (Medtronic) device. In twelve patients the pain was due to cancer and three patients had pain of non malignant origin. All of the patients reported excellent or good relief. A total of 14 complications were reported in 7 patients. Most of these were minor and related to surgical or mechanical problems. One patient with pain of non malignant origin developed serious complications which required the removal of the infusion device. The results of this study show that chronic intrathecal infusion of morphine is superior to conventional forms of analgesia in patients with intractable pain of malignant origin. We would advise that it should remain a therapy of last resort in patients with intractable non malignant pain as the long term side effects are still unknown and the potential for serious side effects still exists.

Over the past two decades, spinal cord stimulation devices and techniques have evolved from single-channel systems, with electrodes requiring laminectomy, into programmable "multichannel" systems with electrodes that may be placed percutaneously. We have reviewed our experience in 320 consecutive patients treated with these devices at our institution between 1972 and 1990. Technical details of treatment as well as patient characteristics have been assessed as predictors of clinical outcome and of hardware reliability by univariate and multivariate statistical methods. Current follow-up has been obtained at intervals from 2 to 20 years (mean, 7.1 yr) postoperatively on 205 patients. All clinical outcome measures have been based on disinterested third-party interview data--standard analog pain ratings, employment status, activities of daily living, and use of analgesics. At 7-year mean follow-up, 52% of the 171 patients who received permanent implants reported at least 50% continued pain relief. A majority had maintained improvements in activities of daily living and analgesic use. Analysis of hardware reliability for 298 permanent implants revealed significantly fewer clinical failures (P < 0.001) and technical failures (in particular, electrode migration and malposition, P = 0.025) as single-channel implants have evolved into programmable, multichannel devices. Our analysis of technical and clinical prognostic factors may be useful to the clinician in selecting patients for this procedure.

The implantation of spinal cord stimulators (SCSs) to treat chronic intractable pain is steadily increasing. And there is an increased likelihood of instances where other therapies or procedures are found to interfere with SCS function, which in turn may result in pain. Since SCS utilize electric impulses as well as magnets, special considerations need for patients with a SCS in situ who require these procedures. The present report describes a case where radiofrequency (RF) ablation of the third occipital nerve resulted in spontaneous activation of a cervical SCS device.

Deep brain stimulation (DBS) was first used for the treatment of pain in 1954. Since that time, remarkable advances have been made in the field of DBS, largely because of the resurgence of DBS for the treatment of movement disorders. Although DBS for pain has largely been supplanted by motor cortex and spinal cord stimulation during the last decade, no solid evidence exists that these alternative modalities truly offer improved outcomes. Furthermore, nuclei not yet fully explored are known to play a role in the transmission and modulation of pain. This article outlines the history of DBS for pain, pain classification, patient selection criteria, DBS target selection, surgical techniques, indications for DBS (versus ablative techniques), putative new DBS targets, complications, and the outcomes associated with DBS for pain.

SCS was found to be cost-effective and therapeutically effective in this study for a majority of patients who had successful trial screening and were determined to be suitable candidates for SCS therapy. This is consistent with prior research if not slightly more encouraging, because typically half of the patients implanted with SCS reported 50% or more pain relief. Strikingly, most patients were considered cost successes. Overall, this study provides continued support that spinal cord stimulation offers the medical community an effective treatment for pain and reduces costs associated with the treatment of chronic intractable pain patients.

Objective : To investigate the effect of chronic pain on processes that generate the mismatch negativity (MMN). Methods :Twelve participants with a diagnosis of chronic intractable pain were tested before and after pain treatment. During testing, event-related potentials were recorded while participants performed tasks of varying difficulty. Results : The amplitude of the MMN was found to be greater following a nerve block procedure compared to MMN amplitude when participants were experiencing chronic pain. This effect was found to occur in the MMN for difficult-to-detect tones elicited while participants were performing a simultaneous cognitively demanding visual task. MMN amplitude was found to be greater with attention to difficult-to-detect deviants during pain but not in no pain conditions. Conclusions : These results provide an electrophysiological correlate of previous findings that high levels of pain disrupt cognition during the performance of demanding tasks.

Neuropsychological manifestations of bilateral anterior cingulate cortex lesions were studied in patients treated with cingulotomy for chronic intractable pain. Cingulotomy patients more than 1 year postsurgery were contrasted with nonsurgical chronic pain patients. Patients were assessed on a neuropsychological battery, including measures of response intention, initiation, generation, and persistence. Cingulotomy patients were intact across most cognitive domains, but they showed deficits of focused and sustained attention as well as mild executive dysfunction. Self-initiated responding--including spontaneous verbal utterances and unstructured design fluency--was most impaired. Results indicate that the greatest impact of cingulotomy lesions is on response intention and self-initiated behavior, with reduced behavioral spontaneity.

Medical advances have not obviated the need for opioids to relieve pain and suffering. There are no better analgesics. Pain and suffering have not abated. Scientific endeavor has helped unravel some of the mechanisms of pain and addiction; yet the compelling and addictive properties of opioids continue to plague their use. This article explores the factors that drive the current debate about the use of opioids to relieve the suffering of patients with chronic intractable pain.

The “gate theory” of pain transmission in the dorsal horn of the spinal cord, published in 1965, provided the foundation for the use of electrical stimulation for pain relief (57). The feasibility of chronic neural stimulation was greatly increased when the miniaturized highly reliable solid-state electronic technology developed for cardiac pacemakers was transferred to implantable neural stimulators.

The intrathecal drug administration system (ITDAS) has recently been introduced for treating chronic intractable pain patients who have failed with conservative pain treatments. The obvious advantages of its use are the direct intrathecal delivery of drugs, which yields reduced adverse effects and the increased strength of drugs, as compared to its oral or intravenous route. This article offers a review of the ITDAS with a brief review of its evidence-based effectiveness, the technical approach, and the complications.

Over the past two decades, spinal cord stimulation devices and techniques have evolved from single-channel systems, with electrodes requiring laminectomy, into programmable "multichannel" systems with electrodes that may be placed percutaneously. We have reviewed our experience in 320 consecutive patients treated with these devices at our institution between 1972 and 1990. Technical details of treatment as well as patient characteristics have been assessed as predictors of clinical outcome and of hardware reliability by univariate and multivariate statistical methods. Current follow-up has been obtained at intervals from 2 to 20 years (mean, 7.1 yr) postoperatively on 205 patients. All clinical outcome measures have been based on disinterested third-party interview data--standard analog pain ratings, employment status, activities of daily living, and use of analgesics. At 7-year mean follow-up, 52% of the 171 patients who received permanent implants reported at least 50% continued pain relief. A majority had maintained improvements in activities of daily living and analgesic use. Analysis of hardware reliability for 298 permanent implants revealed significantly fewer clinical failures (P < 0.001) and technical failures (in particular, electrode migration and malposition, P = 0.025) as single-channel implants have evolved into programmable, multichannel devices. Our analysis of technical and clinical prognostic factors may be useful to the clinician in selecting patients for this procedure.

The use of intraspinal therapy for the management of intractable pain from nonmalignant causes has not been widely discussed. An implantable, externally programmable infusion pump was used for intraspinal delivery of morphine sulfate to 15 patients with intractable pain from reflex sympathetic dystrophy, arachnoiditis after spinal surgery, or an unknown cause. Dosage patterns were individualized. At follow-up ranging from 2 to 44 months, pain relief was reported as excellent by 8 patients, good by 3, and fair by 4. Six patients have returned to work. Two patients chose to terminate therapy. Few complications occurred, but most patients needed increasingly larger doses over time to maintain pain relief. Intraspinal infusion of morphine sulfate by use of an implanted, externally programmable pump is safe and effective in selected patients with intractable pain of nonmalignant origin.