There is a group of patients who, after one or more procedures on the lumbar spine for leg pain, experience no relief or recurrence of their radicular symptoms in the leg. When surgical intervention is no longer considered effective at this stage, these patients are diagnosed with Persistent Spinal Pain Syndrome (PSPS-2; Christelis, 2021) . Spinal cord stimulation (SCS) is consistent with the current state of science and clinical practice for selected individuals (Kallewaard, 2020) with PSPS-2 who experience predominant leg pain (National Health Care Institute, 2019). However, since the publication of this report, new waveforms of spinal cord stimulation (SCS) have emerged as well as closed-loop SCS systems, and it is unknown whether these forms result in improved outcomes for patients compared to traditional tonic SCS (e.g. paresthesia based low frequency SCS).

Summary of Findings

High frequency SCS compared with traditional SCS in PSPS-2

_{^1. Risk of Bias: very serious. Due to lack of blinding, due to study sponsoring by manufacturer. Imprecision: serious. Due to overlap of the upper limit of the 95% confidence interval with the minimal clinically important difference. Inconsistency: serious. Due to conflicting results. Indirectness: serious. Due to broader patient inclusion than PICO.}

_{^2. Imprecision: very serious. Due to overlap of the limits of the 95% confidence interval with the minimal clinically important difference.}

_{^3. Imprecision: very serious. Due to not reaching the optimal information size.}

_{^4. Risk of Bias: very serious. Due to lack of blinding, due to study sponsoring by manufacturer. Imprecision: serious. Due to a small number of events. Indirectness: serious. Due to broader patient inclusion than PICO.}

_{^5. Risk of Bias: very serious. Due to lack of blinding, due to study sponsoring by manufacturer. Imprecision: serious. Due to overlap of the lower limit of the 95% confidence interval with the minimal clinically important difference. Indirectness: serious. Due to broader patient inclusion than PICO.}

DTM - SCS compared with traditional SCS in PSPS-2

_{^1. Risk of Bias: very serious. Due to lack of blinding, due to study sponsoring by manufacturer. Imprecision: serious. Due to overlap of the upper limit of the 95% confidence interval with the minimal clinically important difference.}

_{^2. Risk of Bias: very serious. Due to lack of blinding, due to study sponsoring by manufacturer. Imprecision: very serious. Due to overlap of the limits of the 95% confidence interval with the minimal clinically important difference.}

Closed-loop SCS compared with traditional open-loop SCS in PSPS-2

Description of studies

A total of seven studies describing four study cohorts were included in the analysis of the literature. Important study characteristics and results are summarized in table 2. The assessment of the risk of bias is summarized in the risk of bias tables (under the tab ‘Evidence tabellen’).

High frequency SCS

De Andres (2017) and the SENZA cohort (Amirdelfan 2018, Kapural 2015 and Kapural 2016) compared conventional low frequency tonic stimulation SCS with high frequency SCS. Both studies included patients with chronic pain refractory to traditional treatment. De Andres (2017) only included patients with a previous back surgery (failed back surgery syndrome). However, the SENZA cohort included a mixed population since previous surgery was not an inclusion criterium. Therefore, this study did not adhere fully to the patient population in the predefined PICO. However, 75 to 79 percent of the patients in the groups of the SENZA cohort were diagnosed with PSPS-2. Thus, the working group assumed that results of this study could be generalized to the group defined in or PICO. Following the GRADE rating of evidence we downgraded the evidence found in this study for indirectness.

• Additional inclusion criteria for De Andres (2017) were: >18 years of age, mainly axial low back pain or radiating leg pain that failed to respond to other treatment, an NRS ≥5, a 50% reduction in NRS in the two-week trial period. Exclusion criteria were: unresolved issues of secondary gain or inappropriate medication use, mechanical low back pain, coexisting chronic pain conditions or neurological disease, coexisting conditions increasing procedural risk, a history of laminectomy or posterior fusion, abnormal pain behavior, unresolved psychiatric illness and a negative psychological evaluation.
• Additional inclusion criteria for SENZA were: an Oswestry Disability Index (ODI) between 41 and 80, average back pain VAS ≥50, average leg pain VAS ≥50. Exclusion criteria were: active psychological or psychiatric disorders that can impact perception of pain, mechanical spine instability and prior experience with SCS.

Differential Target Multiplex SCS

Fishman (2021) compared the effectiveness of differential target multiplexed SCS (DTM-SCS) with conventional SCS in the treatment of chronic low back and leg pain. They included adult patients that were a candidate for SCS per labeled indication with a VAS ≥50 with moderate to severe leg pain, stable pain medication for over 30 days and willingness to not increase medication for 3 months. Exclusion criteria were: unresolved legal issues or secondary gain (e.g. work related) or inappropriate medication use, a medical, anatomic, and/or psychosocial condition that contraindicate the SCS neurostimulation system, an existing active implanted device, mechanical spine instability, or an interventional procedure or surgery within 30 days of enrollment which provided pain relief.

Closed-loop SCS

The EVOKE cohort (Mekhail 2020 and 2022) compared traditional low frequency open-loop SCS with closed-loop SCS in patients with chronic intractable pain of the back and legs refractory to conservative therapy that were a candidate for an SCS trial. Patients with and without previous back surgery were included. Therefore, this study did not adhere fully to the patient population in the predefined PICO. However, over 60 percent of the patients in the groups of the EVOKE cohort were diagnosed with PSPS-2. Therefore, the working group assumed that results of this study could be generalized to the group defined in or PICO. Following the GRADE rating of evidence, we downgraded the evidence found in this study for indirectness.

Additional inclusion criteria were: 18 to 80 years of age, overall VAS, back pain VAS ánd leg pain VAS ≥60 cm, an ODI between 41 and 80, stable pain medication and no previous SCS therapy. Exclusion criteria were: active disruptive psychological or psychiatric disorder, medical condition that could interfere with accurate pain reporting, not a surgical candidate, existing implantable device and prior experience with SCS.

Table 2. Characteristics of included studies

_{*For further details, see risk of bias table in the appendix}

Results

Results are presented separately for three different types of new-form SCS: high frequency SCS, differential targeted multiplexed (DTM) SCS and closed-loop SCS.

1. High frequency SCS 

Pain (crucial)

Pain intensity was reported with an 11-point pain intensity numeric rating scale (NRS) or visual analogue scale (VAS), where 0 represents no pain and 10cm (or 100mm) represents the worst possible pain. When VAS scores were presented in millimeters, they were divided by 10 to make comparison between studies possible.

De Andres (2017) reported pain intensity with the NRS at 12 months and did not specify pain location. SENZA reported VAS back pain and leg pain at 24 months. Pain scores are reported in Table 3.

Table 3. Pain - high frequency SCS

Quality of life (crucial)

De Andres (2017) reports on quality of life with the Hospital Anxiety and Depression Scale (HADS) and the mental health component of the Short Form-12 (Table 4). The HADS is a self-assessment scale detecting states of depression, anxiety, and emotional distress. Scales range from 0 to 21 with higher scores indicating greater anxiety, depression, or mood disorders.

The (SF-12) questionnaire results in a physical component summary and a mental component summary. A score above 50 on the SF-12 indicates better functioning than average whereas scores below 50 indicate lower than average quality of life. De Andres (2017) reports the mental health component.

Table 4. Quality of life – high frequency SCS

Function (important)

De Andres (2017) and Senza report on function with the Oswestry Disability Index (ODI). The ODI is condition-specific outcome measures used in the management of spinal disorders. The score ranges from 0 to a 100 with 0 representing no disability and a 100 representing total disability. ODI scores by De Andres (2017) are reported in Table 5.

Table 5. Function reported by De Andres – high frequency SCS

SENZA reported ODI in categories (Table 6).

Table 6. Function reported by Senza – high frequency SCS

_{Abbreviations: ODI – Oswestry Disability Index}

Adverse events (important)

De Andres (2017) reported one lead migration with replacement (3.4%) after twelve months in the high frequency SCS group compared to two (6.5%) in the conventional low frequency SCS group. They reported no infection or complains of pain at implant site.

SENZA reported six study-related adverse events (5.0%) in the high-frequency group compared to eight (7.2%) in the traditional SCS group. They reported that lead migration resulting in surgical revision occurred in 3.0% of high frequency SCS therapy subjects and 5.2% of traditional SCS.

Return to work (important)

None of the included studies reported on return to work.

Use of pain-medication (important)

SENZA reported decreased or eliminated opioid use in 35.5% of the intervention group compared to 26.4% in the traditional SCS group. They also reported on daily morphine equivalents for individuals who were taking opioids at baseline (Table 7).

Table 7. Morphine equivalents – high frequency SCS

2. Differential Targeted Multiplexed (DTM) SCS

Pain (crucial)

Pain intensity was reported with a visual analogue scale (VAS), where 0 represents no pain and 10cm (or 100mm) represents the worst possible. When VAS scores were presented in millimeters, they were divided by 10 to make comparison possible.

Fishman (2021) reports VAS reduction in leg pain and back pain at 12 months (Table 8). No absolute values of pain at follow-up were reported. However a clinicalyl relevant change is VAS is observed for leg and back pain in both the intervention and control condition.

Table 8. Pain reported by Fishman – DTM SCS

Quality of life 

None of the included studies on DTM-SCS reported on quality of life.

Function (important)

Fisman (2021) reports on function with the Oswestry Disability Index (ODI). The ODI is condition-specific outcome measures used in the management of spinal disorders. The score ranges from 0 to a 100 with 0 representing no disability and a 100 representing total disability. Fishman (2021) reports on the ODI in categories (Table 9).

Table 9. Function reported by Fishman –DTM SCS

Adverse events (important)

Fishman (2021) reported four adverse events (6.0%) in the DTM-SCS group compared to eight (13.1%) in the traditional SCS group. Of the adverse events in the DTM SCS-group, two were lead dislodgements. Two serious adverse events (medical device site pain and site infection) occurred in the traditional SCS group (3.3%) of which the infection (1.6%) led to system explant in the trial phase.

Return to work (important)

None of the included studies on DTM-SCS reported on return to work.

Use of pain-medication (important)

None of the included studies on DTM-SCS reported on the use of pain medication. 

3. Closed-loop SCS

Pain (crucial)

EVOKE reports on VAS overall back and leg pain at 24 months. Pain scores are reported in Table 10.

Table 10. Pain – Closed-loop SCS

Quality of life (crucial)

EVOKE reports on quality of life with the SF-12 for the physical and the mental health component and the European Quality of Life Five-Dimensional Five-Level Index score (EQ-5D 5L) at 24 months follow-up.

The (SF-12) questionnaire results in a physical component summary (PCS) and a mental component summary (MCS). A score above 50 on the SF-12 indicates better functioning than average whereas scores below 50 indicate lower than average quality of life. The EQ-5D-DL score ranges from 0 to 1, with 1 representing best health. Quality of life scores are reported in Table 11.

Table 11. Quality of life – closed-loop SCS

Function (important)

EVOKE report on function with the Oswestry Disability Index (ODI) and the Pittsburgh Sleep Quality Index (PSQI) (Table 12). The ODI is condition-specific outcome measures used in the management of spinal disorders. The score ranges from 0 to a 100 with 0 representing no disability and a 100 representing total disability). The PSQI is designed to measure sleep problems and sleep disorders. The score ranges from zero to 21 with lower scores representing better sleep quality. EVOKE only reported change scores for function. No intention to treat analysis was performed. Results are reported in Table 12.

Table 12. Function – closed-loop SCS

Adverse events (important)

EVOKE reported two explants (3%) due to procedure-related infections in the closed-loop group, compared to one (1.5%) in the open-loop group. Furthermore, they reported two explants (3%) due to loss of efficacy in the open-loop group compared to zero in the closed-loop group.

Return to work (important)

None of the included studies reported on return to work.

Use of pain-medication (important)

EVOKE reported on voluntary opioid reduction or elimination of patients who were taking opioids at baseline and on daily morphine milligram equivalents. EVOKE reported a reduction in 18 out of 27 (66.7%) patients in the closed-loop group compared to 14 out of 23 (60.9%) patients in the open-loop group. MME is reported in table 13.

Table 13. Use of pain medication – Closed-loop SCS

A systematic review of the literature was performed to answer the following question:

What are the effects of new forms of SCS compared with low frequency SCS (standard care) for patients with PSPS-2?

Table 1. PICO

Relevant outcome measures

The working group considered pain and quality of life as critical outcome measures for decision making; and functioning/self-sufficiency, return to work, medication use and complications as important outcome measures for decision making.

The working group defined the outcome measures as follows: 

The working group defined a 10% change as a minimal clinically (patient) important difference. This roughly corresponds to a difference of ten points on the Visual Analog Scale (VAS scale: 0 to 100 mm), one point on the Numeric Rating Scale (NRS scale: 0 to 10), and ten points on the Oswestry Disability Index (ODI) (scale 0 to 100).

For risk ratios and odds ratios, the thresholds of 0.91 and 1.1 are applied. Standardized Mean Difference (SMD) is classified as 0.2 (small), 0.5 (moderate), and 0.8 (large).

Search and select (Methods)

The databases Medline (via OVID) and Embase (via Embase.com) were searched with relevant search terms until August 19^th, 2024. The detailed search strategy is listed under the tab ‘Literature search strategy’. The systematic literature search resulted in 850 hits. Studies were selected based on the following criteria:

• Systematic reviews or randomized controlled trials.
• Reported on high frequency SCS, new wave forms for neuromodulation, or closed-loop SCS as intervention.
• Used low frequency SCS paresthesia based SCS as control.
• Reported at least one of the outcomes from the PICO (table 1).
• Provided results over a follow-up of at least 12 months.

Initially, 42 studies were selected based on title and abstract screening. After reading the full text, 35 studies were excluded (see the exclusion table under the tab ‘Evidence tabellen’), and 7 studies (totaling 4 study cohorts) were included.

1. Al-Kaisy A, Palmisani S, Pang D, Sanderson K, Wesley S, Tan Y, McCammon S, Trescott A. Prospective, Randomized, Sham-Control, Double Blind, Crossover Trial of Subthreshold Spinal Cord Stimulation at Various Kilohertz Frequencies in Subjects Suffering From Failed Back Surgery Syndrome (SCS Frequency Study). Neuromodulation. 2018 Jul;21(5):457-465. doi: 10.1111/ner.12771. Epub 2018 Apr 2. PMID: 29608229.
2. Al-Kaisy A, Van Buyten JP, Smet I, Palmisani S, Pang D, Smith T. Sustained effectiveness of 10 kHz high-frequency spinal cord stimulation for patients with chronic, low back pain: 24-month results of a prospective multicenter study. Pain Med. 2014 Mar;15(3):347-54. doi: 10.1111/pme.12294. Epub 2013 Dec 5. PMID: 24308759; PMCID: PMC4282782.
3. Amirdelfan K, Yu C, Doust MW, Gliner BE, Morgan DM, Kapural L, Vallejo R, Sitzman BT, Yearwood TL, Bundschu R, Yang T, Benyamin R, Burgher AH, Brooks ES, Powell AA, Subbaroyan J. Long-term quality of life improvement for chronic intractable back and leg pain patients using spinal cord stimulation: 12-month results from the SENZA-RCT. Qual Life Res. 2018 Aug;27(8):2035-2044. doi: 10.1007/s11136-018-1890-8. Epub 2018 Jun 1. PMID: 29858746.
4. Bayerl S, Paz-Solis J, Matis G, Rigoard P, Kallewaard JW, Canos-Verdecho MA, Vesper J, Llopis JE, Kyriakopoulos G, Gulve A, Raoul S, Papa A, Love-Jones S, Williams A. Two-Year Outcomes Using Fast-Acting, Sub-Perception Therapy for Spinal Cord Stimulation: A European, Real-World, Multicenter Experience. J Clin Med. 2024 Nov 20;13(22):6999. doi: 10.3390/jcm13226999. PMID: 39598142; PMCID: PMC11595255. Brooker C, Russo M, Cousins MJ, Taylor N, Holford L, Martin R, Boesel T, Sullivan R, Hanson E, Gmel GE, Shariati NH, Poree L, Parker J. ECAP-Controlled Closed-Loop Spinal Cord Stimulation Efficacy and Opioid Reduction Over 24-Months: Final Results of the Prospective, Multicenter, Open-Label Avalon Study. Pain Pract. 2021 Jul;21(6):680-691. doi: 10.1111/papr.13008. Epub 2021 May 2. PMID: 33768664; PMCID: PMC8359972.
5. Christelis N, Simpson B, Russo M, Stanton-Hicks M, Barolat G, Thomson S, Schug S, Baron R, Buchser E, Carr DB, Deer TR, Dones I, Eldabe S, Gallagher R, Huygen F, Kloth D, Levy R, North R, Perruchoud C, Petersen E, Rigoard P, Slavin K, Turk D, Wetzel T, Loeser J. Persistent Spinal Pain Syndrome: A Proposal for Failed Back Surgery Syndrome and ICD-11. Pain Med. 2021 Apr 20;22(4):807-818. doi: 10.1093/pm/pnab015. PMID: 33779730; PMCID: PMC8058770.
6. De Andres J, Monsalve-Dolz V, Fabregat-Cid G, Villanueva-Perez V, Harutyunyan A, Asensio-Samper JM, Sanchis-Lopez N. Prospective, Randomized Blind Effect-on-Outcome Study of Conventional vs High-Frequency Spinal Cord Stimulation in Patients with Pain and Disability Due to Failed Back Surgery Syndrome. Pain Med. 2017 Dec 1;18(12):2401-2421. doi: 10.1093/pm/pnx241.
7. Deer T, Slavin KV, Amirdelfan K, North RB, Burton AW, Yearwood TL, Tavel E, Staats P, Falowski S, Pope J, Justiz R, Fabi AY, 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. 2018 Jan;21(1):56-66. doi: 10.1111/ner.12698. Epub 2017 Sep 29. PMID: 28961366.
8. 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. 2021 Nov;21(8):912-923. doi: 10.1111/papr.13066. Epub 2021 Aug 27. PMID: 34363307; PMCID: PMC9290817. MID: 29126228.
9. Goudman L, De Smedt A, Eldabe S, Rigoard P, Billot M, Roulaud M; DETECT consortium; Moens M. Differential target multiplexed spinal cord stimulation in patients with Persistent Spinal Pain Syndrome Type II: a study protocol for a 12-month multicentre cohort study (DETECT). BMJ Open. 2024 Nov 9;14(11):e083610. doi: 10.1136/bmjopen-2023-083610. PMID: 39521475; PMCID: PMC11551985.
10. Head J, Mazza J, Sabourin V, Turpin J, Hoelscher C, Wu C, Sharan A. Waves of Pain Relief: A Systematic Review of Clinical Trials in Spinal Cord Stimulation Waveforms for the Treatment of Chronic Neuropathic Low Back and Leg Pain. World Neurosurg. 2019 Nov;131:264-274.e3. doi: 10.1016/j.wneu.2019.07.167. Epub 2019 Jul 30. PMID: 31369885.
11. Kallewaard JW, Gültuna I, Hoffmann V, Elzinga L, Munnikes R, Verbrugge L, Minne V, Reiters P, Subbaroyan J, Santos A, Rotte A, Caraway D. 10 kHz Spinal Cord Stimulation for the Treatment of Failed Back Surgery Syndrome with Predominant Leg Pain: Results from a Prospective Study in Patients from the Dutch Healthcare System. Pain Pract. 2021 Jun;21(5):490-500. doi: 10.1111/papr.12973. Epub 2020 Dec 22. PMID: 33274545; PMCID: PMC8247309.
12. Kapural L, Yu C, Doust MW, Gliner BE, Vallejo R, Sitzman BT, Amirdelfan K, Morgan DM, Yearwood TL, Bundschu R, Yang T, Benyamin R, Burgher AH. 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. 2016 Nov;79(5):667-677. doi: 10.1227/NEU.0000000000001418. PMID: 27584814; PMCID: PMC5058646.
13. Kapural L, Yu C, Doust MW, Gliner BE, Vallejo R, Sitzman BT, Amirdelfan K, Morgan DM, Brown LL, Yearwood TL, Bundschu R, Burton AW, Yang T, Benyamin R, Burgher AH. Novel 10-kHz High-frequency Therapy (HF10 Therapy) Is Superior to Traditional Low-frequency Spinal Cord Stimulation for the Treatment of Chronic Back and Leg Pain: The SENZA-RCT Randomized Controlled Trial. Anesthesiology. 2015 Oct;123(4):851-60. doi: 10.1097/ALN.0000000000000774. PMID: 26218762.
14. Kallewaard JW, D’eer I, Edelbroek C, Huygen FJPM, Kurt E, Nijhuis HJA, Terwiel CTM, van de Voort TWG, de Vries-Fennis GM. Standpunt Neuromodulatie bij chronische pijn; Geprotocolleerde behandeling met neuromodulatie. 2020 Nederlandse Vereniging voor Anesthesiologie.
15. Mekhail N, Levy RM, Deer TR, Kapural L, Li S, Amirdelfan K, Hunter CW, Rosen SM, Costandi SJ, Falowski SM, Burgher AH, Pope JE, Gilmore CA, Qureshi FA, Staats PS, Scowcroft J, McJunkin T, Carlson J, Kim CK, Yang MI, Stauss T, Pilitsis J, Poree L; Evoke Study Group; Brounstein D, Gilbert S, Gmel GE, Gorman R, Gould I, Hanson E, Karantonis DM, Khurram A, Leitner A, Mugan D, Obradovic M, Ouyang Z, Parker J, Single P, Soliday N. Durability of Clinical and Quality-of-Life Outcomes of Closed-Loop Spinal Cord Stimulation for Chronic Back and Leg Pain: A Secondary Analysis of the Evoke Randomized Clinical Trial. JAMA Neurol. 2022 Mar 1;79(3):251-260. doi: 10.1001/jamaneurol.2021.4998. Erratum in: JAMA Neurol. 2022 Apr 1;79(4):420. doi: 10.1001/jamaneurol.2022.0022. PMID: 34998276; PMCID: PMC8742908.
16. Metzger C, Hammond B, Ferro R, North J, Pyles S, Kranenburg A, Washabaugh E, Goldberg E. Two-year outcomes using fast-acting sub-perception therapy for spinal cord stimulation: results of a real-world multicenter study in the United States. Expert Rev Med Devices. 2025 Jan 16. doi: 10.1080/17434440.2025.2453554. Epub ahead of print. PMID: 39819320.
17. National Health Care Institute (Zorginstituut Nederland). Standpunt Neuromodulatie bij chronsiche pijn. 2019. Derived from: https://www.zorginstituutnederland.nl/binaries/zinl/documenten/standpunten/2019/11/12/standpunt-neuromodulatie-bij-chronische-pijn/Standpunt+neuromodulatie+bij+chronische+pijn.pdf.
18. Nijhuis H, Kallewaard JW, van de Minkelis J, Hofsté WJ, Elzinga L, Armstrong P, Gültuna I, Almac E, Baranidharan G, Nikolic S, Gulve A, Vesper J, Dietz BE, Mugan D, Huygen FJPM. Durability of Evoked Compound Action Potential (ECAP)-Controlled, Closed-Loop Spinal Cord Stimulation (SCS) in a Real-World European Chronic Pain Population. Pain Ther. 2024 Oct;13(5):1119-1136. doi: 10.1007/s40122-024-00628-z. Epub 2024 Jul 2. PMID: 38954217; PMCID: PMC11393244.
19. Nijhuis HJA, Hofsté WJ, Krabbenbos IP, Dietz BE, Mugan D, Huygen F. First Report on Real-World Outcomes with Evoked Compound Action Potential (ECAP)-Controlled Closed-Loop Spinal Cord Stimulation for Treatment of Chronic Pain. Pain Ther. 2023 Oct;12(5):1221-1233. doi: 10.1007/s40122-023-00540-y. Epub 2023 Jul 23. PMID: 37481774; PMCID: PMC10444915.
20. Niyomsri S, Duarte RV, Eldabe S, Fiore G, Kopell BH, McNicol E, Taylor RS. A Systematic Review of Economic Evaluations Reporting the Cost-Effectiveness of Spinal Cord Stimulation. Value Health. 2020 May;23(5):656-665. doi: 10.1016/j.jval.2020.02.005. Epub 2020 Apr 20. PMID: 32389232.
21. Motov S, Aftahy K, Jörger AK, Wagner A, Meyer B, Shiban E. High-frequency spinal cord stimulation in failed back surgery syndrome patients with predominant low back pain-single-center experience. Neurosurg Rev. 2021 Oct;44(5):2809-2818. doi: 10.1007/s10143-020-01462-5. Epub 2021 Jan 17. PMID: 33454835; PMCID: PMC8490248.
22. Mekhail N, Levy RM, Deer TR, Kapural L, Li S, Amirdelfan K, Hunter CW, Rosen SM, Costandi SJ, Falowski SM, Burgher AH, Pope JE, Gilmore CA, Qureshi FA, Staats PS, Scowcroft J, Carlson J, Kim CK, Yang MI, 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. 2020 Feb;19(2):123-134. doi: 10.1016/S1474-4422(19)30414-4. Epub 2019 Dec 20. PMID: 31870766.
23. Mekhail NA, Levy RM, Deer TR, Kapural L, Li S, Amirdelfan K, Pope JE, Hunter CW, Rosen SM, Costandi SJ, Falowski SM, Burgher AH, Gilmore CA, Qureshi FA, Staats PS, Scowcroft J, McJunkin T, Carlson J, Kim CK, Yang MI, Stauss T, Petersen EA, Hagedorn JM, Rauck R, Kallewaard JW, Baranidharan G, Taylor RS, Poree L, Brounstein D, Duarte RV, Gmel GE, Gorman R, Gould I, Hanson E, Karantonis DM, Khurram A, Leitner A, Mugan D, Obradovic M, Ouyang Z, Parker J, Single P, Soliday N; EVOKE Study Group. ECAP-controlled closed-loop versus open-loop SCS for the treatment of chronic pain: 36-month results of the EVOKE blinded randomized clinical trial. Reg Anesth Pain Med. 2024 May 7;49(5):346-354. doi: 10.1136/rapm-2023-104751. PMID: 37640452; PMCID: PMC11103285.
24. Rapcan R, Mlaka J, Venglarcik M, Vinklerova V, Gajdos M, Illes R. High-frequency - Spinal Cord Stimulation. Bratisl Lek Listy. 2015;116(6):354-6. doi: 10.4149/bll_2015_067. PMID: 26084736.
25. Russo M, Cousins MJ, Brooker C, Taylor N, Boesel T, Sullivan R, Poree L, Shariati NH, Hanson E, Parker J. Effective Relief of Pain and Associated Symptoms With Closed-Loop Spinal Cord Stimulation System: Preliminary Results of the Avalon Study. Neuromodulation. 2018 Jan;21(1):38-47. doi: 10.1111/ner.12684. Epub 2017 Sep 18. PMID: 28922517.
26. Russo M, Brooker C, Cousins MJ, Taylor N, Boesel T, Sullivan R, Holford L, Hanson E, Gmel GE, Shariati NH, Poree L, Parker J. Sustained Long-Term Outcomes With Closed-Loop Spinal Cord Stimulation: 12-Month Results of the Prospective, Multicenter, Open-Label Avalon Study. Neurosurgery. 2020 Sep 15;87(4):E485-E495. doi: 10.1093/neuros/nyaa003. Erratum in: Neurosurgery. 2020 Sep 1;87(3):611. doi: 10.1093/neuros/nyaa332. PMID: 32023344; PMCID: PMC8184296.
27. Torres-Bayona S, Mattar S, Arce-Martinez MP, Miranda-Acosta Y, Guillen-Burgos HF, Maloof D, Samprón N, Farah JO; High frequency spinal cord stimulation for chronic back and leg pain. Interdisciplinary Neurosurgery. 2021 March; 23. doi: 10.1016/j.inat.2020.101009.