
==== Front
Interv Pain Med
Interv Pain Med
Interventional Pain Medicine
2772-5944
Elsevier

S2772-5944(23)00095-X
10.1016/j.inpm.2023.100263
100263
Original Article
Real-world outcomes of single-stage spinal cord stimulation in chronic pain patients: A multicentre, European case series
De Negri Pasquale pasquale.denegri@aorncaserta.it
a∗
Paz-Solis Jose Francisco b
Rigoard Philippe cd
Raoul Sylvie e
Kallewaard Jan-Willem fg
Gulve Ashish h
Thomson Simon i
Canós-Verdecho Maria Angeles j
Love-Jones Sarah j
Williams Adam k
Rascón-Ramírez Fernando J. l
Bayerl Simon m
Llopis-Calatayud José Emilio n
Peña Vergara Isaac o
Matis Georgios K. p
Vesper Jan q
Abejón David r
Maino Paolo s
Papa Alfonso t
Pei Yu u
Jain Roshini u1
a Department of Anesthesia, Sant’Anna and San Sebastiano Hospital, Caserta, Italy
b Department of Neurosurgery, University Hospital La Paz, Madrid, Spain
c Predictive Research in Spine/Neuromodulation Management and Thoracic Innovation/Cardiac Surgery Lab, Poitiers University Hospital, Poitiers, France
d Department of Neuro-Spine & Neuromodulation, Poitiers University Hospital, Poitiers, France
e Department of Neurosurgery, Nantes University Hospital, Nantes, France
f Department of Anesthesiology and Pain Medicine, Rijnstate Hospital, Arnhem, the Netherlands
g Amsterdam University Medical Centre, Amsterdam, the Netherlands
h Department of Pain Medicine, The James Cook University Hospital, Middlesbrough, UK
i Department of Pain Medicine and Neuromodulation, Mid and South Essex University Hospitals, Essex, UK
j Multidisciplinary Unit for Pain Treatment, University and Polytechnic Hospital La Fe, Valencia, Spain
k Department of Pain Medicine and Neuromodulation, Southmead Hospital, Bristol, United Kingdom
l Neurosurgery Service, Hospital Clínico San Carlos, Madrid, Spain
m Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
n Service of Anesthesiology, Resuscitation and Therapeutics of Pain, University Hospital La Ribera, Alzira, Valencia, Spain
o Andalusian Health Service, University Hospital Virgen del Rocío, Seville, Spain
p Department of Stereotactic and Functional Neurosurgery, University Hospital Cologne, Cologne, Germany
q Department of Neurosurgery, University Hospital Düsseldorf, Düsseldorf, Germany
r Multidisciplinary Pain Management Unit, University Hospital Quirónsalud, Madrid, Spain
s Neurocenter of Southern Switzerland, Lugano Regional Hospital, Lugano, Switzerland
t Pain Department, A.O. Dei Colli - V. Monaldi Hospital, Napoli, Italy
u Division of Neuromodulation, Boston Scientific, Valencia, CA, USA
∗ Corresponding author. Via Palasciano, Caserta, Italy. pasquale.denegri@aorncaserta.it
1 No longer presently employed at the Division of Neuromodulation, Boston Scientific.

24 6 2023
9 2023
24 6 2023
2 3 1002635 4 2023
31 5 2023
1 6 2023
© 2023 The Authors
2023
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Background

Spinal cord stimulation (SCS) is effective in treating chronic neuropathic pain. A screening trial is typically conducted prior to implantation to evaluate whether a patient is a good candidate for SCS. However, the need for a screening trial has been debated. We evaluated real-world clinical outcomes in patients who underwent a single-stage procedure to receive SCS therapy (i.e., no screening trial period) (SS-SCS).

Methods

This observational, multicentre, real-world consecutive case series evaluated SS-SCS chronic pain patients. Pain and other functional outcomes were collected as part of standard care by site personnel with no sponsor involvement. Assessments included Numerical rating scale (NRS), Percent Pain Relief (PPR) and EQ-5D-5L (EuroQol 5 Dimensions-5L), recorded prior to SCS and following implantation.

Results

A total of 171 chronic pain patients (mean age: 59.4; 53.2% females) underwent a single-stage procedure (mean last follow-up, 408 days) and were included in the analysis. A 5.0 ​± ​2.1-point improvement in overall pain was reported at 3 months and sustained until the last follow-up post-implantation (p ​< ​0.0001). At last follow-up, 50.3% (86/171) of patients reported an NRS pain score ≤3. Additionally, quality of life also improved (46.1-point change, from 70.2 to 25) at the last follow-up, based on EQ-5D-5L scores.

Conclusions

In routine clinical practice, SS-SCS can provide significant long-term pain relief and improve quality of life in chronic pain patients. Our results suggest that effective long-term outcomes and success may be achieved without a trial period prior to permanent implantation of an SCS system.

Keywords

Chronic pain
Neuromodulation
Single-stage procedure
Spinal cord stimulation
Trial screening
Abbreviations

EQ-5D EuroQol 5 Dimensions

NRS numerical rating scale

SS-SCS single-stage spinal cord stimulation
==== Body
pmc1 Introduction

Spinal cord stimulation (SCS) is an effective treatment in the management of chronic neuropathic pain [1,2]. Typically, patients who have been selected as good candidates are implanted with leads during a first-stage procedure and undergo a temporary trial period to experience SCS therapy using an external test stimulator. Based on the success of their trial period, the neurostimulator is then implanted in a second stage. This practice varies across countries. There is also a wide variability in trial period duration (days to weeks). The utility of a trial period prior to permanent implantation has been debated, particularly with respect to its clinical value (i.e., predictor of SCS success) and its burden on healthcare resources in the treatment of chronic pain [[3], [4], [5]]. In the Trial-Stim study, for example, there were no differences in the primary outcome (mean pain), proportion of pain responders or other secondary outcomes between the trial screening and no trial screening groups, but trial screening was associated with a higher cost [3].

It is important to note that understanding of the utilisation of SCS therapy has evolved since its first introduction. Patient selection for SCS is now better understood and has been refined over time in relation to physical and psychosocial factors [6,7]. Recent multidimensional patient profiling solutions, using digital tools or machine-learning algorithms, have proposed new ways for identifying the best candidates for SCS and for predicting the response of patients’ response to therapy [[8], [9], [10], [11]]. A recent European consensus study led to the development of a patient profiling e-health tool, which helps clinicians identify or confirm candidates for SCS therapy. In a retrospective applicability study of 483 patients implanted with an SCS system, 133 patients proceeded to permanent implant without a trial period. Results from this study suggest that patients who were deemed “appropriate” in the patient e-tool profile at baseline tended to have better SCS outcomes, regardless of whether they had a trial or not. This highlights the relevance of patient selection in determining the predictor of success for SCS.

Over the last 15 years, the capabilities of neurostimulators have expanded to enable delivery of multiple stimulation modalities that may differ in their mechanism of action or the sensation they produce in patients (e.g., paraesthesia versus sub-perception) [[12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23]]. Results from a randomised controlled trial (RCT) demonstrated that a device capable of providing multiple therapies provided superior long-term outcomes when subjects were able to choose the most effective therapy [24]. Combination therapy (simultaneous delivery of modalities) enabled more patients to achieve a successful outcome that monotherapy alone [25]. SCS is no longer a monotherapy where a single waveform is utilised; instead, multiple programming strategies are available to personalise therapy for each patient [26]. Therefore, trial periods that implement a monotherapy may underrepresent the capabilities of SCS therapy and may result in false negatives [5,27], thus failing to appropriately screen SCS responders, especially during a trial of short duration. Furthermore, no difference in long-term pain relief has been observed with acute (i.e. intraoperative) SCS screening compared with prolonged screening [4]. Results from a recent RCT showed no additional benefit in long-term patient outcomes with the use of an externalised trial period [3].

In addition, the risk of infection is higher with prolonged trial periods (>10 days) [28] and some patients may present with other comorbidities (e.g., diabetes, lymphoproliferative disease) that increases the risk of infection. In such cases, a single-stage procedure for SCS may be considered advantageous [29,30]. From a patient perspective, a single stage SCS procedure is preferred as it would result in less time off work (e.g. in hospital, attending appointments), less caregiver support, avoid any device-related concerns (e.g. loose wires connected to the external test stimulator that may become unplugged, resulting in loss of therapy) and ultimately reduced health cost [31]. Higher costs and related healthcare resources are incurred with SCS screening [3,32]. Thus, it would be prudent to challenge the need for a systematic externalised screening trial period as a pre-requisite prior to the implantation of an SCS system.

Accordingly, we evaluated the real-world clinical outcomes of patients who underwent a single-stage procedure for SCS (SS-SCS) (i.e., on-table testing prior to immediate implantation, no external temporary trial period) as part of an ongoing case-series. Our hypothesis was that SS-SCS patients would experience effective, long-term pain relief, thus increasing the evidence base for minimising the use of trial screening in SCS.

2 Materials and methods

Real-world data was collected as part of a multicentre, observational, consecutive case series (Clinicaltrials.gov: NCT01550575) for chronic pain patients who had undergone a single-stage procedure for SCS implantation (i.e., no external temporary trial period) in 18 centres across Europe. All patients provided written, informed consent as per local regulatory requirements. The study was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committees from each site.

2.1 Study participants

All consecutive chronic pain patients aged ≥18 years who had an SS-SCS implantation were included in the data analysis. All participants were deemed eligible to SCS therapy, in compliance with local regulations and device directions for use. Decision for a single-stage procedure was taken by each site based on their clinical judgment, current practice and/or standard of care. There were no exclusion criteria per study protocol.

2.2 Device description

Various SCS systems were utilised, including Spectra WaveWriter, WaveWriter Alpha, Montage, Novi, Precision, Precision Spectra SCS System (Boston Scientific, Valencia, CA, USA). Based on clinician choice, percutaneous or paddle leads were introduced into the epidural space, offering a range of eight to 32 contacts available for therapy programming. Depending on each clinician's decision and regular practice, on-table testing was performed followed by IPG implantation, where the leads were connected during the same procedure. The SCS systems have a wide range of programming capabilities that allow SCS therapy to be tailored to each patient, including multiple, independent current control (MICC) with Illumina 3D™ targeting, combination therapy, multiple sub-perception waveforms (customised Burst, MicroBurst 3D, high rate (up to 1.2 ​kHz), FAST™ therapy), advanced field shapes (Contour™), and waveform automation.

2.3 Study outcomes

All data were collected by site personnel, as per standard practice and without any sponsor involvement. Demographic information and outcome measures were documented, including pain location, pain severity and improvement following SCS implant. Overall pain scores were documented using a Numerical Rating Scale (NRS) from 0 (no pain) to 10 (worst pain). NRS scores ≤3 correspond to mild pain, 4–6 to moderate pain, and ≥7 to severe pain [33]. Quality of life was assessed using the EuroQol 5 Dimensions (EQ-5D)-5L questionnaire, using a visual analogue scale (VAS) scored from 0 (‘the worst health you could imagine’) to 100 (‘the best health you could imagine’). Population norms reported in Europe for the EQ-5D-5L VAS are around 70–80 [[34], [35], [36]]. SCS device settings and patients' most preferred SCS waveforms and therapies were also recorded.

2.4 Statistical analysis

A Kolmogorov–Smirnov Test was performed to confirm the normality of the change in NRS score. Score distribution was calculated for the NRS pain scores. A paired t-test with two-sided 0.05 significance level was used to calculate whether the mean reduction in baseline pain at 3, 6 and 12 months was greater than 0. Continuous variables are presented as mean ​± ​standard deviation.

3 Results

3.1 Baseline characteristics

A total of 171 patients (91 women, 80 men), with a mean age of 59.4 ​± ​13.7 years who had undergone SS-SCS were included in the analysis. Patients were implanted with SCS systems between July 2012 and June 2022 and were diagnosed with one or more of the following: failed back surgery syndrome or persistent spinal pain 2 (PSP2) (46.6%), spinal stenosis (10.4%), lumbosacral radiculopathy or PSP1 (8.4%), complex regional pain syndrome (6%), and various other conditions. Pain locations varied among patients, with most of them reporting low back and leg pain (81.9%) followed by pain in the lower limbs (56.7%).

A mean overall pain of 8.1 ​± ​1.2 (n ​= ​171) was reported at baseline (pre-implant), indicating that these chronic pain patients were experiencing severe pain. Patient-reported mean low back and leg pain scores were 7.9 ​± ​1.8 (n ​= ​134) and 8.2 ​± ​1.3 (n ​= ​141), respectively. The mean EQ-5D-5L score at baseline was 25.0 ​± ​2.0 (n ​= ​91). Table 1 provides details of baseline and clinical characteristics.Table 1 Patient characteristics (n ​= ​171).

Table 1Sex (females), n (%)	91 (53.2)	
Age, mean (SD) a	59.4 (13.7)	
Pain location (may have multiple locations), n (%)		
 Low back and legs	140 (81.9)	
 Lower limbs	97 (56.7)	
 Upper limbs	12 (7.0)	
 Head/neck	11 (6.4)	
Key diagnosis for receiving SCS (may have multiple diagnosis), n (%)		
Failed back surgery syndrome (persistent spinal pain 2)	116 (46.6)	
Spinal stenosis	26 (10.4)	
Lumbosacral radiculopathy (persistent spinal pain 1)	21 (8.4)	
Complex regional pain syndrome	15 (6.0)	
Baseline overall pain score (NRS), mean (SD)	8.1 (1.2)	
EQ-5D 5L, mean (SD)	25.0 (19.3) b	
a n ​= ​147.

b n ​= ​91. NRS, numerical rating scale (from 0 to 10); SD, standard deviation.

3.2 Clinical outcomes

A mean 5.0 ​± ​2.1-point improvement (from 8.1 to 3.1; n ​= ​109) in overall pain was reported at 3 months post-implantation and sustained at 12 months (Fig. 1). At last follow-up (mean duration 408 days), the mean overall pain score had improved by 4.6 ​± ​2.4 points (from 8.1 to 3.5; n ​= ​171; p ​< ​0.0001) (Fig. 2). Similar significant improvements (p ​< ​0.0001) were noted in low back pain and leg pain, with a reduction in pain scores of 4.5 ​± ​2.5 points (from 8.0 to 3.4; n ​= ​129) and 5.1 ​± ​2.2 points (from 8.3 to 3.2; n ​= ​115), respectively (Fig. 2). A 2-point improvement in pain scores is considered clinically significant at the last follow-up, the responder rate was 71.3%, with 122/171 patients experiencing ≥50% improvement in pain compared to baseline. An NRS pain score of ≤3 ​at the last follow-up was reported in 50.3% (86/171) of patients (Fig. 3).Fig. 1 Overall pain, low back and leg pain scores at baseline and up to 12 months post-implant (mean ​± ​standard error).

Fig. 1

Fig. 2 Overall pain, low back, and leg pain scores at baseline and up to last follow-up (mean ​= ​408 days) (mean ​± ​standard error).

Fig. 2

Fig. 3 Distribution of overall pain scores at last follow-up (mean ​= ​408 days). 50.3% (86 of 171 patients) reported a pain score ≤3.

Fig. 3

A 46.1-point improvement in EQ-5D-5L was noted at the last follow-up (from 25 to 70.2; n ​= ​83), demonstrating improved quality of life in patients with data available (Fig. 4).Fig. 4 Mean quality of life at last follow-up (mean ​= ​408 days), assessed using the EQ-5D-5L (0 ​= ​‘the worst health you could imagine’ to 100 ​= ​‘the best health you could imagine’). A 46.1-point improvement in EQ-5D-5L was noted.

Fig. 4

3.3 SCS therapy and programming

All commercially approved leads were available for use in this real-world cohort. Lead information was available for 160 patients (274 total leads).

Eight- or 16-contact percutaneous leads were used in 87% of patients (148/171), while 16-contact or 32-contact paddle leads were implanted in 7.6% of patients (13/171). Two leads were implanted in 57.3% of these patients (n ​= ​99), while a single lead was used in 32.1% of patients (n ​= ​55). Three or four leads were used in three patients each (n ​= ​6). Information related to number of leads implanted was not provided in 11 patients.

Of these, 59.4% (163 leads) were placed with the lead tip at T8 level and 11.7% (N ​= ​32) were at T9 level (Fig. 5). In 62.6% of cases (171/273 leads), epidural leads were positioned midline, while 31.1% (85/273) were paramedial. Various neurostimulation therapies were used by patients over time. At the last follow-up (mean duration 408 days, i.e., 1.1 years), the most preferred programs were sub-perception waveforms (48%), followed by combination therapy (34%) and standard rate therapy (18%) (Table 2).Fig. 5 Distribution of lead location (lead tip shown) among n ​= ​171 patients. Information related to 11 patients was not provided.

Fig. 5

Table 2 Patients’ preferred programs/waveforms at last follow-up (408 days; n ​= ​171).

Table 2Preferred program/waveform, n (%) a		
Combination therapy	59 (35)	
Standard rate with MICC (tonic)	31 (18)	
Sub-perception with Burst or Microburst 3D	29 (16)	
Sub-perception with FAST therapy	27 (15)	
Sub-perception with high rate (up to 1.2 ​kHz) or Contour	26 (15)	
Other	7 (4)	
a Note that some patients may have preferred multiple waveforms. MICC, multiple independent current control.

4 Discussion

The clinical value of an SCS trial stimulation period before SCS implantation has come under some scrutiny in recent years [[3], [4], [5],9]. Trials may not reflect the potential for pain relief [3] and also place a burden on healthcare resources and on patients [32,37]. A single-stage SCS procedure, where patients are tested on-table prior to immediate implantation, could help to alleviate not only the strain on healthcare systems [32], but may also be a preferred option for chronic pain patients [31]. However, as widely now reported, there do exist significant advantages as well as possible limitations of a single-stage SCS procedure when compared to “dual”-staged procedures (Table 3).Table 3 Reported Advantages (“Pros”) and Disadvantages (“Cons) of Single vs Dual Staged SCS Procedure(s).

Table 3	Pros (i.e., reported advantages)	Cons (i.e. reported disadvantages	
Dual-Stage SCS (i.e., screening trial followed by permanent implantation)	• Allows patients to experience SCS before permanent implant procedure [3,31]

• Ease of removal of SCS device apparatus and equipment during trial if deemed necessary [31]

• Provides for a baseline from which to evaluate magnitude of achievable pain relief response [39]

• Can facilitate more careful selection of SCS device and/or neurostimulative modality or programming approach for use in a future permanent implantation [31]

	• Screening trials may not be accurately predictive of long-term SCS outcomes and may underrepresent the capabilities of SCS resulting in false negatives and/or inappropriate screening out of potential responders [37,40]

• Increased risk of infection [3,28,39]

• Duplicative procedures requiring added consumption of healthcare resources [6,32]

• Requires an increased number of appointments and time away from employment, and in some patients imposes additional travel obligation [31]

	
Single-Stage SCS (i.e., no screening trial; “on-table” testing followed by permanent implant)	• Decreased infection risk [3,28,39]

• Less consumption of healthcare resources [6,32]

• Lower number of appointments needed thereby less travel and “time off” required [31]

• Only 1 time period of hospital admission and/or recovery needed [31]

	• Does not allow patients a “preview” of SCS therapy prior to undergoing procedure [3]

• Proceeding straight to permanent SCS implant may be difficult for some patients [31]

	

Recently, RCT-derived evidence has demonstrated no significant difference in pain relief between patients who underwent SCS with no trial screening period compared to those who underwent one [3,38]. For example, in both assessed groups in the TRIAL-STIM RCT, the NRS pain score decreased by ​> ​3.0 points at 6 months compared to baseline, and ∼40% of patients in both groups similarly achieved ≥50% pain relief. Furthermore, long-term follow-up analyses at 36-months recapitulated these results per determination of no significant differences in pain relief and/or likelihood of explant between patients who underwent a trial versus those who did not [38]. Our real-world, multicentre study described here was designed to obtain outcomes in a cohort of SCS patients implanted with no screening trial period, as typically done per the standard of care in each centre. In so doing, there was no direct involvement of the sponsor as it pertains to the collection of data at each of the participating study sites.

Results from this observational case-series demonstrate significant improvement in overall pain, low back, and leg pain over 408 days (last follow-up). Patients reported severe pain prior to SCS implant and experienced a highly significant 5.0-point improvement from baseline that was noted 3 months after implantation and sustained for up to 12 months. At the last follow-up, more than half of SS-SCS patients reported a pain score ≤3. The reduction in pain relief was accompanied by a significant improvement in quality of life. The EQ-5D-5L VAS, which was low at baseline (25 points), increased to a mean value of 70.2 points after SS-SCS at the last follow-up, indicating that the patients’ quality of life had reached population norms for healthy people in Europe [[34], [35], [36]]. Additionally, the real-world evidence obtained in this study demonstrates that SCS implantation can be performed in a single-stage procedure while maintaining long-term pain relief and quality of life. These findings, combined with observations from earlier studies [3,4], suggest that critical analysis and/or revision of established clinical practice guidelines for SCS should be considered to reflect individual patient needs and the selection process for SCS therapy. Presently however, mandatory requirements in some European countries (e.g., France, Netherlands, and Belgium) enforce the undertaking of an SCS trial to ensure insurance reimbursement. While in other counties, though not obligatory, initial assessment of all candidates for SCS within the context of a screening trial is still commonly preferred among implanting providers. Yet, the growing compendium of publicly reported clinical and health economic evidence, of which this current analysis now contributes, increasingly supports the implementation of a single-stage SCS procedure in appropriately selected patients [3,31,32,[37], [38], [39], [40]]. Accordingly, there is now a drive to individualize the diagnosis and treatment of chronic pain patients such that personalised (sometimes referred to as “patient-centered”) care is emphasized [41]. Thus, we assert that rather than making screening trials compulsory (as in specific countries), offering patients for whom SCS therapy is highly recommended [8], a single-stage implantation procedure (per the standard discussion of potential risks and benefits), may in fact represent a more “patient-centered” approach that is of greater preference and ultimate benefit to those seeking to more effectively manage their chronic pain. This approach though should not impede the ability to impose a compulsory screening trial when the conditions of select patients are clearly more challenging, making it therefore more difficult to anticipate the benefits of SCS.

This study does have limitations. Comparison with a matched control group from the same case-series would have been beneficial to corroborate whether the real-life clinical improvements in SS-SCS patients were at least as good as in those who first underwent trial screening. The number of patients fluctuated over the 12-month period of the analysis, but this reflects clinical practice, where for various reasons patients are often unable to make a follow-up appointment. It might also have been of value to analyse other outcomes (e.g., patient satisfaction) to indirectly compare with results from controlled clinical trials in patients who underwent trial screening for SCS. However, such outcomes are not often recorded as standard in clinical practice. In addition, the retrospective nature of our design might be associated with the risk of selection bias that is inherent in retrospective studies. However, we included all patients who underwent SS-SCS, without any exclusion criteria.

5 Conclusions

Our real-world evidence demonstrates that a single-stage implantation procedure for SCS, without a trial screening period, not only provides long-term pain relief and improves quality of life in patients with chronic pain, but also avoids delay in patient care and could reduce overall healthcare-related costs. Careful patient selection and the use of contemporary platforms that are safe and can readily adapt to the patient's dynamic pain situation of the patient will alleviate suffering, pain and associated functional impairments. A more flexible policy based on individual patient needs and preferences is needed.

Funding

The study was sponsored by 10.13039/100008497 Boston Scientific and personnel from the Clinical Research Department were involved in the study design (RJ), analysis (RJ, YP), interpretation of the data (RJ), writing of the manuscript (RJ) and overall decision to submit the article for publication. 10.13039/100008497 Boston Scientific also funded the services of the medical writer (Deborah Nock, Medical WriteAway, Norwich, UK).

Declaration of competing interest

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Pasquale De Negri reports administrative support, statistical analysis, and writing assistance were provided by Boston Scientific Neuromodulation. Pasquale De Negri reports a relationship with Boston Scientific Neuromodulation that includes: non-financial support. This study was sponsored by 10.13039/100008497 Boston Scientific , and personnel from the Clinical Research Department within Boston Scientific’s Division of Neuromodulation were involved in the study design (RJ), analysis (RJ, YP), interpretation of the data (RJ), writing of the manuscript (RJ) and overall decision to submit the article for publication. 10.13039/100008497 Boston Scientific also funded the services of the medical writer (Deborah Nock, Medical WriteAway, Norwich, UK). Drs. Jose F. Paz-Solis, Philippe Rigoard, Sylvie Raoul, Simon Thomson and Georgios K. Matis declare active consulting agreements with Boston Scientific. Dr. Abejón is a consultant and speaker for Boston Scientific, Saluda Médical, Medtronic and Abbott, Devonlabs, Cardiva2 and Grünenthal. Yu Pei and Roshini Jain are employees of Boston Scientific. This study is sponsored by 10.13039/100008497 Boston Scientific .

Acknowledgements

Writing and editorial support was provided by Deborah Nock (Medical WriteAway, Norwich, UK), funded by 10.13039/100008497 Boston Scientific , and Daniel Halperin, PhD.
==== Refs
References

1 Fatima K. Javed S.O. Saleem A. Marsia S. Zafar R. Noorani K. Kumar S. Ali S.M. Ismail I. Hashim I. Ganatra F.A. Long-term efficacy of spinal cord stimulation for chronic primary neuropathic pain in the contemporary era: a systematic review and meta-analysis J Neurosurg Sci 2023 Mar 21 10.23736/S0390-5616.23.05930-1 Epub ahead of print. PMID: 36943763
2 Fontaine D. Spinal cord stimulation for neuropathic pain Rev Neurol (Paris) 177 7 2021 Sep 838 842 10.1016/j.neurol.2021.07.014 Epub 2021 Aug 9. PMID: 34384626 34384626
3 Eldabe S. Duarte R.V. Gulve A. Thomson S. Baranidharan G. Houten R. Jowett S. Sandhu H. Chadwick R. Brookes M. Kansal A. Earle J. Bell J. Robinson J. Walker S. Rhodes S. Taylor R.S. Does a screening trial for spinal cord stimulation in patients with chronic pain of neuropathic origin have clinical utility and cost-effectiveness (TRIAL-STIM)? A randomised controlled trial Pain 161 12 2020 Dec 2820 2829 32618875
4 Weinand M.E. Madhusudan H. Davis B. Melgar M. Acute vs. Prolonged screening for spinal cord stimulation in chronic pain Neuromodulation 6 1 2003 15 19 https://10.1046/j.1525-1403.2003.03002.x 22150909
5 Oakley J.C. Krames E.S. Stamatos J. Foster A.M. Successful long-term outcomes of spinal cord stimulation despite limited pain relief during temporary trialing Neuromodulation 11 1 2008 66 73 https://10.1111/j.1525-1403.2007.00145.x 22150994
6 Goudman L. Rigoard P. Billot M. Duarte R.V. Eldabe S. Moens M. Patient selection for spinal cord stimulation in treatment of pain: sequential decision-making model - a narrative review J Pain Res 15 2022 1163 1171 https://10.2147/jpr.S250455 35478997
7 Thomson S. Helsen N. Prangnell S. Paroli M. Baranidharan G. Belaïd H. Patient selection for spinal cord stimulation: the importance of an integrated assessment of clinical and psychosocial factors Eur J Pain 26 9 2022 1873 1881 https://10.1002/ejp.2009 35856311
8 Thomson S. Huygen F. Prangnell S. De Andrés J. Baranidharan G. Belaïd H. Appropriate referral and selection of patients with chronic pain for spinal cord stimulation: European consensus recommendations and e-health tool Eur J Pain 24 6 2020 1169 1181 https://10.1002/ejp.1562 32187774
9 Thomson S. Huygen F. Prangnell S. Baranidharan G. Belaïd H. Billet B. Applicability and validity of an e-health tool for the appropriate referral and selection of patients with chronic pain for spinal cord stimulation: results from a European retrospective study Neuromodulation 26 1 2023 164 171 https://10.1016/j.neurom.2021.12.006 35088755
10 Ounajim A. Billot M. Goudman L. Louis P.Y. Slaoui Y. Roulaud M. Machine learning algorithms provide greater prediction of response to SCS than lead screening trial: a predictive AI-based multicenter study J Clin Med 20 2021 10 https://10.3390/jcm10204764 35011750
11 Goudman L. Van Buyten J.P. De Smedt A. Smet I. Devos M. Jerjir A. Predicting the response of high frequency spinal cord stimulation in patients with failed back surgery syndrome: a retrospective study with machine learning techniques J Clin Med 9 12 2020 https://10.3390/jcm9124131
12 Kapural L. Yu C. Doust M.W. Gliner B.E. Vallejo R. Sitzman B.T. Amirdelfan K. Morgan D.M. Yearwood T.L. Bundschu R. Yang T. Benyamin R. Burgher A.H. Comparison of 10-kHz high-frequency and traditional low-frequency spinal cord stimulation for the treatment of chronic back and leg pain: 24-month results from a multicenter, randomized, controlled pivotal trial Neurosurgery 79 5 2016 Nov 667 677 10.1227/NEU.0000000000001418 PMID: 27584814; PMCID: PMC5058646 27584814
13 Deer T. Slavin K.V. Amirdelfan K. North R.B. Burton A.W. Yearwood T.L. Tavel E. Staats P. Falowski S. Pope J. Justiz R. Fabi A.Y. Taghva A. Paicius R. Houden T. Wilson D. Success using neuromodulation with BURST (SUNBURST) study: results from a prospective, randomized controlled trial using a novel Burst waveform Neuromodulation 21 1 2018 Jan 56 66 10.1111/ner.12698 Epub 2017 Sep 29. PMID: 28961366 28961366
14 Wille F. Breel J.S. Bakker E.W. Hollmann M.W. Altering conventional to high density spinal cord stimulation: an energy dose-response relationship in neuropathic pain therapy Neuromodulation 20 1 2017 Jan 71 80 10.1111/ner.12529 Epub 2016 Oct 24. PMID: 27778413 27778413
15 Fishman M. Cordner H. Justiz R. Provenzano D. Merrell C. Shah B. Naranjo J. Kim P. Calodney A. Carlson J. Bundschu R. Sanapati M. Mangal V. Vallejo R. Twelve-Month results from multicenter, open-label, randomized controlled clinical trial comparing differential target multiplexed spinal cord stimulation and traditional spinal cord stimulation in subjects with chronic intractable back pain and leg pain Pain Pract 21 8 2021 Nov 912 923 10.1111/papr.13066 Epub 2021 Aug 27. PMID: 34363307; PMCID: PMC9290817 34363307
16 Mekhail N. Levy R.M. Deer T.R. Kapural L. Li S. Amirdelfan K. Hunter C.W. Rosen S.M. Costandi S.J. Falowski S.M. Burgher A.H. Pope J.E. Gilmore C.A. Qureshi F.A. Staats P.S. Scowcroft J. Carlson J. Kim C.K. Yang M.I. Stauss T. Poree L. Evoke Study Group Long-term safety and efficacy of closed-loop spinal cord stimulation to treat chronic back and leg pain (Evoke): a double-blind, randomised, controlled trial Lancet Neurol 19 2 2020 Feb 123 134 10.1016/S1474-4422(19)30414-4 Epub 2019 Dec 20. PMID: 31870766 31870766
17 Veizi E. Hayek S.M. North J. Brent Chafin T. Yearwood T.L. Raso L. Spinal cord stimulation (SCS) with anatomically guided (3D) neural targeting shows superior chronic axial low back pain relief compared to traditional SCS-LUMINA study Pain Med 18 8 2017 1534 1548 https://10.1093/pm/pnw286 28108641
18 Thomson S.J. Tavakkolizadeh M. Love-Jones S. Patel N.K. Gu J.W. Bains A. Effects of rate on analgesia in kilohertz frequency spinal cord stimulation: results of the PROCO randomized controlled trial Neuromodulation 21 1 2018 67 76 https://10.1111/ner.12746 29220121
19 Paz-Solís J. Thomson S. Jain R. Chen L. Huertas I. Doan Q. Exploration of high- and low-frequency options for subperception spinal cord stimulation using neural dosing parameter relationships: the HALO study Neuromodulation 25 1 2022 94 102 https://10.1111/ner.13390 35041592
20 Metzger C.S. Hammond M.B. Pyles S.T. Washabaugh E.P. 3rd Waghmarae R. Berg A.P. Pain relief outcomes using an SCS device capable of delivering combination therapy with advanced waveforms and field shapes Expet Rev Med Dev 17 9 2020 951 957 https://10.1080/17434440.2020.1812383
21 Kallewaard J.W. Paz-Solis J.F. De Negri P. Canós-Verdecho M.A. Belaid H. Thomson S.J. Real-world outcomes using a spinal cord stimulation device capable of combination therapy for chronic pain: a European, multicenter experience J Clin Med 10 18 2021 https://10.3390/jcm10184085
22 Metzger C.S. Hammond M.B. Paz-Solis J.F. Newton W.J. Thomson S.J. Pei Y. A novel fast-acting sub-perception spinal cord stimulation therapy enables rapid onset of analgesia in patients with chronic pain Expet Rev Med Dev 18 3 2021 299 306 https://10.1080/17434440.2021.1890580
23 Gilbert J.E. Titus N. Zhang T. Esteller R. Grill W.M. Surround inhibition mediates pain relief by low amplitude spinal cord stimulation: modeling and measurement eNeuro 9 5 2022 https://10.1523/eneuro.0058-22.2022
24 North J. Loudermilk E. Lee A. Sachdeva H. Kaiafas D. Washabaugh E. Outcomes of a multicenter, prospective, crossover, randomized controlled trial evaluating subperception spinal cord stimulation at ≤1.2 kHz in previously implanted subjects Neuromodulation 23 1 2020 102 108 https://10.1111/ner.13015 31265205
25 Wallace M.S. North J.M. Phillips G.M. Calodney A.K. Scowcroft J.A. Popat-Lewis B.U. Combination therapy with simultaneous delivery of spinal cord stimulation modalities: COMBO randomized controlled trial Pain Manag 2023 https://10.2217/pmt-2022-0101
26 Berg A.P. Mekel-Bobrov N. Goldberg E. Huynh D. Jain R. Utilization of multiple spinal cord stimulation (SCS) waveforms in chronic pain patients Expet Rev Med Dev 14 8 2017 663 668 https://10.1080/17434440.2017.1345621
27 Haider N. Ligham D. Quave B. Harum K.E. Garcia E.A. Gilmore C.A. Spinal cord stimulation (SCS) trial outcomes after conversion to a multiple waveform SCS system Neuromodulation 21 5 2018 504 507 https://10.1111/ner.12783 29889356
28 North R. Desai M.J. Vangeneugden J. Raftopoulos C. Van Havenbergh T. Deruytter M. Postoperative infections associated with prolonged spinal cord stimulation trial duration (PROMISE RCT) Neuromodulation 23 5 2020 620 625 https://10.1111/ner.13141 32267989
29 Sica A. Casale B. Sagnelli C. Di Dato M.T. Buonavolontà P. Salzano A.M. All-in-One spinal cord stimulation in lymphoproliferative diseases Front Neurol 11 2020 550554 https://10.3389/fneur.2020.550554
30 Neuromodulation Society of UK & Ireland Guidance on resumption of neuromodulation services during the COVID-19 recovery phase July 2020 Date accessed: 21 October 2022. Available from https://nsuki.memberclicks.net/assets/documents/NSUKI/COVID/Recovery/Guidance.pdf
31 Chadwick R. McNaughton R. Eldabe S. Baranidharan G. Bell J. Brookes M. To trial or not to trial before spinal cord stimulation for chronic neuropathic pain: the patients' view from the TRIAL-STIM randomized controlled trial Neuromodulation 24 3 2021 459 470 https://10.1111/ner.13316 33258531
32 Duarte R.V. Houten R. Nevitt S. Brookes M. Bell J. Earle J. Screening trials of spinal cord stimulation for neuropathic pain in England-A budget impact analysis Front Pain Res (Lausanne) 3 2022 974904 https://10.3389/fpain.2022.974904
33 Boonstra A.M. Stewart R.E. Köke A.J. Oosterwijk R.F. Swaan J.L. Schreurs K.M. Cut-off points for mild, moderate, and severe pain on the numeric rating scale for pain in patients with chronic musculoskeletal pain: variability and influence of sex and catastrophizing Front Psychol 7 2016 1466 https://10.3389/fpsyg.2016.01466 27746750
34 Grochtdreis T. Dams J. König H.-H. Konnopka A. Health-related quality of life measured with the EQ-5D-5L: estimation of normative index values based on a representative German population sample and value set Eur J Health Econ 20 6 2019 933 944 https://10.1007/s10198-019-01054-1 31030292
35 Hobbins A. Barry L. Kelleher D. O'Neill C. The health of the residents of Ireland: population norms for Ireland based on the EQ-5D-5L descriptive system - a cross sectional study HRB Open Res 1 2018 22 https://10.12688/hrbopenres.12848.1 32002510
36 Garratt A.M. Hansen T.M. Augestad L.A. Rand K. Stavem K. Norwegian population norms for the EQ-5D-5L: results from a general population survey Qual Life Res 31 2 2022 517 526 https://10.1007/s11136-021-02938-7 34272631
37 Duarte R.V. Thomson S. Trial versus No trial of spinal cord stimulation for chronic neuropathic pain: cost analysis in United Kingdom national health service Neuromodulation 22 2 2019 208 214 https://10.1111/ner.12898 30536992
38 Eldabe S. Nevitt S. Griffiths S. Gulve A. Thomson S. Baranidharan G. Houten R. Brookes M. Kansal A. Earle J. Bell J. Taylor R.S. Duarte R.V. Does a screening trial for spinal cord stimulation in patients with chronic pain of neuropathic origin have clinical utility (TRIAL-STIM)? 36-Month results from a randomized controlled trial Neurosurgery 92 1 2023 Jan 1 75 82 36226961
39 Chincholkar M. Eldabe S. Strachan R. Brookes M. Garner F. Chadwick R. Gulve A. Ness J. Prospective analysis of the trial period for spinal cord stimulation treatment for chronic pain Neuromodulation 14 6 2011 Nov-Dec 523 528 21854495
40 Leech H.X. Provenzano D.A. Kilgore J.S. Spinal cord stimulation trialing: is trialing predictive of short, intermediate, and long-term pain outcomes? [Abstract]. Twenty-First annual pain medicine meeting of the American society of regional anesthesia and pain medicine, Orlando, FL 2022 November 17-19
41 U S Department of Health and Human ServicesAlliance to Advance Comprehensive Integrative Pain Management Pain management best practices inter agency task force report 2019 https://painmanagementalliance.org/resources/hhs-report-2019/
