Quantitative Sensory Testing for Spinal Cord Stimulation in Patients With Chronic Neuropathic Pain

Objective: A prospective pilot study was conducted, attempting to identify objective tests that would help clinicians to assess the efficacy of spinal cord stimulation (SCS) trial preceding permanent device implantation. Setting: Four university hospitals in the United States and Israel. Participants: Thirteen patients with radicular leg pain due to failed back surgery syndrome (FBSS) or leg pain due to complex regional pain syndrome (CRPS) who were candidates for SCS. Methods: Participants underwent a series of quantitative sensory tests prior to, and seven days after the initiation of SCS trial. These tests included: vibration threshold (conducted using the VSA 3000; Medoc Inc., Ramat Ishay, Israel), cold threshold, warm threshold, heat pain threshold, phasic heat pain threshold, tonic heat pain threshold (conducted using the TSA 2001; Medoc Inc.), and electrical pain tolerance at 5, 250 and 2000 Hz (administered using the NerveScan^TM 2000; Neurotron, Inc., Baltimore, MD, U.S.A.). Results: Useful data were obtained from 12 patients. The results of the vibration threshold and the tolerance to electrical stimulation at 5 and 250 Hz changed with an SCS trial. These results also correlated with the decision regarding the permanent implantation, which was made independently of them. In contrast, the results of thermal thresholds and tolerance to electrical stimulation at 2000 Hz tests did not change with the SCS trial. Conclusions: Our findings, which agree with those of a few other studies, suggest that the vibration threshold and the tolerance to electrical stimulation at 5 and 250 Hz tests can assist the clinician to select the right patients for permanent stimulation.     

Is Spinal Cord Stimulation an Effective Treatment Option for Discogenic Pain?

Introduction: In a prospective observational study conducted in an urban pain management center, we evaluated whether spinal cord stimulation (SCS) is effective in relieving discogenic pain of IDD origin. Methods: Thirteen patients with intractable discogenic low back pain were enrolled. Four patients never underwent permanent implantation due to insurance denial, medical reasons or failed trial and served as a control group. Nine patients underwent SCS implantation (treatment group). All patients were followed for 12 months and assessed at each interval for pain (NRS), disability (ODI), and opioid use. Results: Nine patients completed the SCS trial with > 50% pain relief. The pretrial NRS score was 7.8 ± 0.5 mm in treated patients vs. 6.5 ± 1.7 mm in control patients. At 3, 6 and 12 months, the NRS was reduced to 2.9 ± 0.7 mm, 1.7 ± 0.5 mm, and 2.9 ± 0.5 mm, respectively in treated patients. NRS was unchanged in the control patients (6.5 ± 1.9 mm). The ODI score prior to the SCS trial in treated patients was 53.1 ± 3.4% vs. 54.0 ± 20.5 in control patients. At 3, 6 and 12 months the ODI scores were 39.0 ± 8.0%, 38.7 ± 4.6%, and 41.1 ± 3.9%, respectively in the treated patients, and 48.5 ± 29.5 at 12 months in control patients. In 6 patients receiving opioids prior to the SCS trial, average consumption was reduced by 69% (P = 0.036) over 12 months of therapy as compared with a 54% increase in the control patients. SCS usage was stable over the 12‐month study. Conclusions: The current study indicates that SCS may provide effective pain relief, improve disability, and reduce opioid usage in patients with discogenic pain.     

Thoracic Spinal Cord Stimulation for Post-Ablation Cardiac Pain in a Patient with Permanent Pacemaker

Background: Spinal cord stimulation (SCS) is increasingly utilized for inoperable, intractable chest pain because of ischemia. Because patients with ischemic heart disease commonly have permanent cardiac pacemakers (PPM) or automated implantable cardio‐defibrillators (AICD), concurrent use of SCS and PPM or AICD may grow. Interference between SCS and PPM or AICD devices is potentially dangerous and has been previously reported. Case report: A 51‐year‐old woman who underwent multiple catheter‐based cardiac ablations for a variety of tachy‐atrial arrhythmias. These procedures included atrioventricular node destruction, which left her PPM‐dependent (third degree heart block with an intrinsic heart rate in the 30s). During the course of her cardiac treatment, she developed chest pain which was not amenable to cardiac intervention and was refractory to medical management. The patient was evaluated for consideration of SCS and ultimately underwent implantation. Procedures evaluating SCS–PPM compatibility were followed and are described. Immediately after SCS implantation and at 6 months follow‐up, the patient experienced improved pain relief. Discussion: Others have reported SCS implantation in patients with PPM. This is the first report to describe safe and effective use of an Advanced Bionics® SCS in a patient with a Guidant® PPM. In addition, we speculate that this patient's cardiac pain may have been other than ischemic in origin. As such, this case may represent a unique clinical scenario. Despite many cases series and case reports demonstrating safety of concurrent SCS and PPM or AICD, the complexity of these technologies requires continued demonstration of device compatibility in novel contexts. ?     

Treatment of Urinary Voiding Dysfunction Syndromes With Spinal Cord Stimulation

This case report presents the use of spinal cord stimulation (SCS) in a patient with urinary incontinence who had previously undergone trial and implantation of InterStim therapy (Medtronic Neurological, Minneapolis, MN). The patient also experienced bilateral lower extremity pain and low back pain related to post-laminectomy syndrome. Having failed all conservative treatment, the patient underwent SCS trial and subsequent implantation. In the postoperative period using SCS therapy, the patient had excellent relief of urinary incontinence symptoms, along with relief of low back pain and bilateral lower extremity pain and was able to discontinue use of InterStim therapy. For this patient, SCS was effective in controlling the urinary voiding dysfunction symptoms, bilateral lower extremity pain and back pain. The use of SCS to treat urinary incontinence problems deserves further study to explore its therapeutic potentials.     

Simultaneous intrathecal opioid pump and spinal cord stimulation for pain management: analysis of 11 patients with failed back surgery syndrome

Dual-modality management of failed back surgery syndrome (FBSS) using a combination of an intrathecal opioid pump (IOP) and spinal cord stimulator (SCS) has not been investigated. The authors performed a retrospective review of 11 patients (8 men, 3 women) with FBSS who underwent nonsimultaneous surgical implantation of both an IOP and a thoracic SCS. Chart review and structured phone interviews were performed to obtain follow-up. Of the two modalities, 3 patients (27%) had an IOP placed first and 8 patients (73%) had a SCS implanted initially. Mean follow-up was 41.7 months (3-97 months). All 11 patients (100%) stated that the dual-modality treatment improved their quality of life and all continue to use both an IOP and SCS for pain control. Six patients (55%) felt that the IOP provided superior pain relief as compared to the SCS, 4 patients (36%) felt that IOP and SCS provided a similar degree of pain relief, and 1 patient (9%) said the SCS provided better pain relief than the IOP. Nine patients (82%) claimed that dual-modality treatment improved their activities of daily living. Nine patients (82%) reported that the combination of IOP and SCS treatment had allowed them to significantly decrease their oral pain medication requirements. Seven patients (64%) had hardware-related complications which required surgery; of this group, 2 patients (18%) needed more than one operation. Six patients (55%) had minor postoperative complications, which were managed nonoperatively. Overall, 10 patients (91%) were glad that they had implantation of both an IOP and SCS and would recommend this combined therapy to other patients. Dual neuroaugmentative treatment with an IOP and thoracic SCS can be safely performed and may provide satisfactory pain relief in appropriately selected patients with FBSS.     

Intrathecal baclofen as adjuvant therapy to enhance the effect of spinal cord stimulation in neuropathic pain: a pilot study.

Only about 60-70% of well selected patients with neuropathic pain syndromes of peripheral origin enjoy sufficient pain relief with spinal cord stimulation (SCS). Since recent animal experiments have demonstrated that the GABA-B receptor is pivotal in the effect of SCS on certain neuropathic symptoms, the use of baclofen as an adjunct to stimulation emerged as an option in patients not responding satisfactorily to SCS. Forty-eight patients with neuropathic pain of peripheral origin responding poorly to SCS were enrolled in a study with intrathecal baclofen; in a few cases adenosine was also tried. Twenty patients reported significant pain reduction at bolus trials and were offered implantation of a drug pump. Seven patients subsequently had pumps implanted together with SCS and four had pumps alone. Three patients had only peroral baclofen therapy as an adjunct to SCS. The 14 patients continuing with baclofen therapy as an adjunct to SCS, or alone, were followed for an average of 35 months after pump implant. The group with SCS+pump n=5; 2 explanted) reported an average decrease of pain ratings from VAS 82 to 33. The group with i.t. baclofen only had a pain decrease from VAS 63 to 33, while the three patients with peroral baclofen+SCS had less benefit from drug therapy. Adjunctive drug therapy for patients with unsatisfactory pain relief by SCS may offer a possibility to enhance pain alleviation.     

Ogilvie's syndrome after paddle spinal cord stimulator implantation: An experience report

Spinal cord stimulation (SCS) is an emerging technology to treat chronic pain from complex regional pain syndrome (CPRS) neuropathy and post-laminectomy syndrome. A rarely reported postoperative complication of SCS paddle implantation is abdominal pain that can result from thoracic radiculopathy. Ogilvie's syndrome (OS) is a disorder characterized by acute dilatation of the colon in the absence of an anatomic lesion that obstructs the flow of intestinal contents, which has seldom been observed after spine surgery. Here, we describe the case of a 70-year-old male who developed OS after SCS paddle implantation resulting in cecal perforation and multi-system organ failure with lethal outcome. We discuss the pathophysiology, present a method measuring the spinal canal to cord ratio (CCR) to prevent the risk of thoracic radiculopathy and OS after paddle SCS implantation, and propose suggestions for management and treatment of this condition.     

Use of Spinal Cord Stimulation in the Treatment of Phantom Limb Pain: Case Series and Review of the Literature

Introduction: Despite technical advances in spinal cord stimulation (SCS), there is a paucity of recent literature regarding SCS for phantom limb pain. Methods: Between January 2003 and May 2008, four patients at M.D. Anderson Cancer Center underwent SCS for intractable phantom limb pain. A retrospective chart review was performed to assess outcomes and complications. A PubMed search was performed to review previously published series regarding the efficacy of SCS for phantom limb pain. Results: Postoperatively, all patients subjectively reported excellent pain relief (>80%). Patients were all followed with the Brief Pain Inventory. Patients 1 to 3 each reported a two‐point decrease in their usual amount of pain using the numerical rating scale. Patient 4's numerical pain scale was unchanged. When using an 11‐point scale to assess other symptomology along 10 dimensions, patients 1 to 3 demonstrated a decrease in their total symptom score by 13, 14, and 4 points, respectively. Patient 4 reported an increase by 5 points in his total symptom score. With regard to complications, patient 2 developed an allergic dermatitis to the generator requiring revision with a polyfluoroethylene (GorTex) pouch. Patient 3 developed a surgical site infection after an implantable pulse generator change. Patients 2 to 4 were very satisfied with their stimulator and would choose to undergo implantation again, with patient 1 having an equivocal response. Conclusions: For selected patients who have not obtained adequate relief with medical management, SCS for phantom limb pain can prove an effective intervention. ?     

Spinal Cord Stimulation as a Treatment Option for Intractable Neuropathic Cancer Pain

Nearly 6,750,000 people suffer moderate to severe cancer-related pain each year. Unfortunately, 10% to 15% of these patients fail to achieve acceptable pain relief with conventional management. Spinal cord stimulation (SCS) has been used with increased frequency for successful treatment of intractable cancer pain. We present two cases of intractable, refractory-to-conventional treatment cancer pain that were successfully treated with SCS. Case 1 reports a 51-year-old male with burning pain at the left groin site of inguinal metastases, post-surgical and intraoperative radiation therapy for treatment of squamous cell carcinoma of the anus. Case 2 reports a 43-year-old woman with intractable, burning, throbbing, and shooting pain, post-debulking followed by radiation of a metastatic colon carcinoma. In both cases SCS implantation provided 90% to 100% pain relief, improved functioning and sleep, and discontinuation of pain medications, sustained through 12 months.     

Therapy Habituation at 12 Months: Spinal Cord Stimulation Versus Dorsal Root Ganglion Stimulation for Complex Regional Pain Syndrome Type I and II

The ACCURATE randomized, controlled trial compared outcomes of dorsal root ganglion (DRG) stimulation versus tonic spinal cord stimulation (SCS) in 152 subjects with chronic lower extremity pain due to complex regional pain syndrome (CRPS) type I or II. This ACCURATE substudy was designed to evaluate whether therapy habituation occurs with DRG stimulation as compared to SCS through 12-months. A modified intention-to-treat analysis was performed to assess percentage pain relief (PPR) and responder rates at follow-up visits (end-of-trial, 1, 3, 6, 9, 12-months postpermanent implant) for all subjects that completed trial stimulation (DRG:N = 73, SCS:N = 72). For both groups, mean PPR was significantly greater at end-of-trial (DRG = 82.2%, SCS =0 77.0%) than all other follow-ups. Following permanent DRG system implantation, none of the time points were significantly different from one another in PPR (range = 69.3–73.9%). For the SCS group, PPR at 9-months (58.3%) and 12-months (57.9%) was significantly less than at 1-month (66.9%). The responder rate also decreased for the SCS group from 1-month (68.1%) to 12-months (61.1%). After stratifying by diagnosis, it was found that only the CRPS-I population had diminishing pain relief with SCS. DRG stimulation resulted in more stable pain relief through 12-months, while tonic SCS demonstrated therapy habituation at 9- and 12-months.Trial Registration: The ACCURATE study was registered at ClinicalTrials.gov with Identifier NCT01923285.PerspectiveThis article reports on an ACCURATE substudy, which found that long-term therapy habituation occurred at 12-months with SCS, but not DRG stimulation, in patients with CRPS. The underlying mechanisms of action for these results remain unclear, although several lines of inquiry are proposed.     

Efficacy of desipramine in painful diabetic neuropathy: a placebo-controlled trial

Although amitriptyline relieves pain in many patients with painful diabetic neuropathy, side effects often preclude effective treatment. Desipramine has the least anticholinergic and sedative effects of the first generation tricyclic antidepressants. We compared a 6 week course of desipramine (mean dose, 201 mg/day) to active placebo in 20 patients with painful diabetic neuropathy in a double-blind crossover trial. Pain relief with desipramine was statistically significant in weeks 5 and 6. Eleven patients reported at least moderate relief with desipramine, compared to 2 with placebo. Pain relief tended to be greater in depressed patients, but relief was also observed in patients who did not show an antidepressant effect. We conclude that desipramine relieves pain in many patients with painful diabetic neuropathy, offering an alternative for patients unable to tolerate amitriptyline. Blockade of norepinephrine reuptake, an action shared by desipramine, amitriptyline, and other antidepressants proven effective in neuropathic pain, may mediate this analgesic effect.     

Amelioration of lower limb pain and foot drop with 10 kHz spinal cord stimulation: A case series

There are limited treatment options for patients with foot drop and associated lower back and/or leg pain. We present a case series of three patients who received permanent implantation of 10 kHz spinal cord stimulation (10 kHz SCS) devices. Following treatment, all patients reported sustained improvements in lower back and leg pain, foot mechanics and function which resulted in increased mobility and cessation of opioid use for pain management. Patients were followed up for approximately four years. Treatment with 10 kHz SCS may be a promising alternative to other interventional procedures commonly used for these patients.     

Transcutaneous electrical nerve stimulator trial may be used as a screening tool prior to spinal cord stimulator implantation

This is a prospective pilot study looking at the utility of Transcutaneous Electrical Nerve Stimulator (TENS) trial as a screening tool prior to spinal cord stimulator (SCS) implant to identify patients who may fail a SCS trial. The accepted screening test prior to a permanent SCS implant is a SCS trial. Patients may fail the SCS trial due to several causes of which one is the inability to tolerate stimulation induced paresthesias. Twenty five patients scheduled for a SCS trial for the treatment of refractory pain secondary to Failed Back surgery syndrome underwent a TENS trial and psychological evaluation by personnel uninvolved in the SCS trial. Data was collected by personnel not involved in the SCS trial or permanent placement. Twenty patients completed the study. Data collected included area of coverage, paresthesia tolerance, pain and anxiety measured on a VAS scale. Comparability between the groups were analyzed using Pearson’s correlation, Fisher Exact test and simple regression analysis. We noted a significant correlation between ability to tolerate TENS and SCS induced paresthesias. Statistically significant correlation was also noted between pre SCS trial anxiety score and high pain score during SCS trial. We conclude that there is potential applicability of a TENS trial as a non invasive screening tool which may promote cost effectiveness and decrease unnecessary procedural risks to the patient by avoiding SCS trial in select patients.     

Successful pain relief in non-responders to spinal cord stimulation: The combined use of ketamine and spinal cord stimulation

Although spinal cord stimulation (SCS) is an established therapy for chronic neuropathic pain, still 30% of patients do not respond adequately to trial stimulation. These so called “non-responders” do not receive a permanent implantation for pain relief.The induction and maintenance of central sensitization plays a pivotal role in (chronic) neuropathic pain and is thought to be the resultant of the activation of the N-methyl-d-aspartate (NMDA) receptor in the dorsal horn. Blocking the NMDA receptor through the use of the non-competitive blocker ketamine has shown to attenuate neuropathic pain, although the undesirable side effects limit its use. The present study was performed to examine whether the combination of SCS with an individually determined sub-effective dose of intrathecal (i.t.) ketamine could convert non-responders into responders in rats with chronic neuropathic pain. Rats received a partial ligation of the sciatic nerve for the induction of neuropathic pain. Animals with tactile hypersensitivity to von Frey monofilaments (n = 15) received 30 min of SCS. Non-responders to SCS (n = 8) received their individually determined sub-effective i.t. dose of ketamine followed by 30 min of SCS. No side effects of the sub-effective dose of ketamine could be noted. The combined treatment of SCS and sub-effective dose of i.t. ketamine in non-responders resulted in a significant reduction of the withdrawal threshold in all previous non-responders to SCS, thereby converting them into responders to SCS.     

Spinal cord stimulation in adolescents with complex regional pain syndrome type I (CRPS‐I)

Complex regional pain syndrome type I (CRPS‐I) is not uncommon in children, particularly in adolescent girls. Most often, the condition involves a foot and is characterized by spontaneous pain, tactile allodynia and dysautonomic signs. There is usually a history of a minor, local trauma but sometimes no reasonable cause can be identified, and there are no signs of persistent tissue injury giving rise to ongoing nociception. Common analgesics are generally of no benefit, and the standard treatment includes sociopsychological support, physiotherapy, tricyclic antidepressants and antiepileptic drugs, sympathetic blocks (SB), and cognitive‐behavioural therapy. For a minority of patients who prove to be resistant to such therapies, spinal cord stimulation (SCS) may be tried. The present study comprises seven girls, 11–14 years of age, presenting with severe, incapacitating and therapy‐resistant CRPS‐I, who were subjected to SCS. In two of them, percutaneous electrode implantation had to be performed in general anaesthesia. Trial stimulation was performed in all, but one. In two cases, it was not possible to produce paraesthesias that entirely covered the pain area. A pain relieving effect of SCS was usually not reported until after 1–2 weeks of trial stimulation. After another 2–6 weeks, pain alleviation was complete in five of the seven patients, one to eight years after the intervention. In one case, a local infection necessitated the removal of the electrode; nevertheless a few days of trial stimulation produced substantial pain relief that still persists. In four patients, the SCS use was gradually diminished and eventually the device could be removed. The favourable outcome in all seven cases with no or minor remaining symptoms and without severe recurrences illustrates that SCS may also be an efficient treatment in paediatric cases with exceptionally therapy resistant forms of CRPS I.     

A Double-Blind,Placebo-Controlled,Crossover Pilot Trial With Extension Using an Oral Mucosal Cannabinoid Extract for Treatment of Chemotherapy-Induced Neuropathic Pain

ContextNeuropathic pain caused by chemotherapy limits dosing and duration of potentially life-saving anti-cancer treatment and impairs quality of life. Chemotherapeutic neuropathy responds poorly to conventional treatments, and there is an urgent medical need for new treatments. Recent preclinical studies demonstrate that cannabinoid agonists suppress established chemotherapy-evoked neuropathy.ObjectivesThis was a pilot trial to begin to investigate a currently available cannabinoid agent, nabiximols (oral mucosal spray containing cannabinoids), in the treatment of chemotherapy-induced neuropathic pain.MethodsA randomized, placebo-controlled crossover pilot study was done in 16 patients with established chemotherapy-induced neuropathic pain. A 0–10 point numeric rating scale for pain intensity (NRS-PI) was used as the primary outcome measure.ResultsWhen examining the whole group, there was no statistically significant difference between the treatment and the placebo groups on the NRS-PI. A responder analysis demonstrated that there were five participants who reported a two-point or greater reduction in pain that trended toward statistical significance and the number needed to treat was five.ConclusionChemotherapy-induced neuropathic pain is particularly resistant to currently available treatments. This pilot trial found a number needed to treat of five and an average decrease of 2.6 on an 11-point NRS-PI in five “responders” (as compared with a decrease of 0.6 with placebo) and supports that it is worthwhile to study nabiximols in a full randomized, placebo-controlled trial of chemotherapy-induced neuropathic pain.     

Spinal cord stimulation in sympathetically maintained complex regional pain syndrome type I with severe disability. A prospective clinical study.

BACKGROUND AND PURPOSE: In this prospective trial we assessed the long-term effect of spinal cord stimulation (SCS) on the improvement of functional status in complex regional pain syndrome type I (CRPS I). METHODS: A prerequisite for eligibility to SCS treatment was the responsiveness of patients to sympathetic nerve block. In 29 patients with chronic sympathetically maintained CRPS I, the efficacy of SCS on deep pain, allodynia and functional disability was determined. Pain intensity was estimated during SCS free intervals of 45 min (inactivation test) every 3 months and compared with that under SCS treatment. RESULTS: On SCS treatment, both deep pain and allodynia could be permanently reduced from 10 to 0-2 on a 10 cm visual analogue scale (VAS) (p<0.01). During the inactivation tests, reoccurrence of pain up to 8 VAS (quartiles 6-8) was measured. Considerable impairments in daily living activities, objectified by the pain disability index, were also restored (p<0.01). After a follow-up period of 35.6+/-21 months, 12 of 16 patients with affected upper limb showed significant increase of the fist grip strength from 0 to 0.35 (quartiles 0.1-0.5) kg compared with 0.9 (quartiles 0.7-1.1) kg on the unaffected side (p<0.01). Eight of ten patients with lower limb disability resumed walking without crutches. Previous pain medication could be significantly reduced (p<0.01). CONCLUSIONS: As a result of permanent pain relief under long-term SCS combined with physiotherapy, the functional status and the quality of life could be significantly improved in sympathetically maintained CRPS I.     

Spinal cord stimulation for complex regional pain syndrome: a systematic review of the clinical and cost-effectiveness literature and assessment of prognostic factors.

OBJECTIVE: To review the clinical and cost-effectiveness of spinal cord stimulation (SCS) in the management of patients with complex regional pain syndrome (CRPS) and identify the potential predictors of SCS outcome. DESIGN: Systematic review of the literature and meta-regression. METHODS: Electronic databases were searched for controlled and uncontrolled studies and economic evaluations relating to the use of SCS in patients with either CRPS type I or II. RESULTS: One randomised controlled trial, 25 case series and one cost-effectiveness study were included. In the randomised controlled trial in type I CRPS patients, SCS therapy lead to a reduction in pain intensity at 24 months of follow-up (mean change in VAS score -2.0), whereas pain was unchanged in the control group (mean change in VAS score 0.0) (p<0.001). In the case series studies, 67% (95% CI 51%, 84%) of type I and type II CRPS patients implanted with SCS reported pain relief of at least 50% over a median follow-up period of 33 months. No statistically significant predictors of pain relief with SCS were observed in multivariate meta-regression analysis across studies. An economic analysis based on the randomised controlled trial showed a lifetime cost saving of approximately 58,470 (60,800 US dollars) with SCS plus physical therapy compared with physical therapy alone. The mean cost per quality-adjusted life-year at 12-month follow-up was 22,580 (23,480 US dollars). CONCLUSIONS: SCS appears to be an effective therapy in the management of patients with CRPS type I (Level A evidence) and type II (Level D evidence). Moreover, there is evidence to demonstrate that SCS is a cost-effective treatment for CRPS type I.     

A prospective study of BurstDR™ spinal cord stimulation for non-operated discogenic low back pain

Introduction

Chronic discogenic low back pain (CD-LBP) is caused by degeneration of the disc due to trauma to the annulus or by unprovoked degeneration, resulting in chronic pain. Spinal cord stimulation (SCS) employing the BurstDR™ waveform has been shown to be an effective treatment in a variety of chronic pain conditions. The aim of this prospective case study was to determine the effect of BurstDR™ SCS on pain relief, disability, and patient satisfaction in a population with CD-LBP.

Methods

Seventeen subjects with CD-LBP received a SCS trial with BurstDR™ stimulation. Patients with >50% pain relief after a trial period of 2 weeks were permanently implanted (n = 15). Patients then rated LBP and leg pain using the numeric rating scale (NRS), Oswestry disability index (ODI), patient global impression of change (PGIC), EQ-5D quality of life, and painDETECT for neuropathic pain at baseline following trial, 3, 6, and 12 months after permanent implantation.

Results

Treatment with BurstDR™ SCS resulted in significant reduction of LBP as the NRS was reduced from 71.7 ± 7.3 at baseline to 42.5 ± 18.1 at 12 months. Average pain relief at 12 months was 42.5%. In patients with leg pain (n = 8), pain was significantly reduced from 66.9 ± 8.2 to 11.7 ± 10.4 at 12 months. PainDETECT scores for neuropathic pain significantly reduced from 18.9 ± 4.8 at baseline, and 14.8 ± 3.2 at 12 months. Baseline ODI score significantly reduced from 41.2 ± 12.8 to 25.8 ± 8.6 at 12 months. PGIC scores remained low from 2.6 ± 1.6 at 3 months, 2.5 ± 1.0 at 6 months, and 2.5 ± 1.3 at 12 months. EQ-5D-5L rates remained constant from baseline 56.10 ± 23.9 to 68.6 ± 12.9 at 12 months.

Conclusion

BurstDR™ SCS resulted in significant reduction of back pain, leg pain, and quality of life in patients with CD-LBP and decreased the level of disability and generated positive patient satisfaction scores.     

Spinal cord stimulation for patients with failed back surgery syndrome or complex regional pain syndrome: a systematic review of effectiveness and complications

We conducted a systematic review of the literature on the effectiveness of spinal cord stimulation (SCS) in relieving pain and improving functioning for patients with failed back surgery syndrome and complex regional pain syndrome (CRPS). We also reviewed SCS complications. Literature searches yielded 583 articles, of which seven met the inclusion criteria for the review of SCS effectiveness, and 15 others met the criteria only for the review of SCS complications. Two authors independently extracted data from each article, and then resolved discrepancies by discussion. We identified only one randomized trial, which found that physical therapy (PT) plus SCS, compared with PT alone, had a statistically significant but clinically modest effect at 6 and 12 months in relieving pain among patients with CRPS. Similarly, six other studies of much lower methodological quality suggest mild to moderate improvement in pain with SCS. Pain relief with SCS appears to decrease over time. The one randomized trial suggested no benefits of SCS in improving patient functioning. Although life-threatening complications with SCS are rare, other adverse events are frequent. On average, 34% of patients who received a stimulator had an adverse occurrence. We conclude with suggestions for methodologically stronger studies to provide more definitive data regarding the effectiveness of SCS in relieving pain and improving functioning, short- and long-term, among patients with chronic pain syndromes.