scholarly journals Time-dynamic pulse modulation of spinal cord stimulation reduces mechanical hypersensitivity and spontaneous pain in rats

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Muhammad M. Edhi ◽  
Lonne Heijmans ◽  
Kevin N. Vanent ◽  
Kiernan Bloye ◽  
Amanda Baanante ◽  
...  

AbstractEnhancing the efficacy of spinal cord stimulation (SCS) is needed to alleviate the burden of chronic pain and dependence on opioids. Present SCS therapies are characterized by the delivery of constant stimulation in the form of trains of tonic pulses (TPs). We tested the hypothesis that modulated SCS using novel time-dynamic pulses (TDPs) leads to improved analgesia and compared the effects of SCS using conventional TPs and a collection of TDPs in a rat model of neuropathic pain according to a longitudinal, double-blind, and crossover design. We tested the effects of the following SCS patterns on paw withdrawal threshold and resting state EEG theta power as a biomarker of spontaneous pain: Tonic (conventional), amplitude modulation, pulse width modulation, sinusoidal rate modulation, and stochastic rate modulation. Results demonstrated that under the parameter settings tested in this study, all tested patterns except pulse width modulation, significantly reversed mechanical hypersensitivity, with stochastic rate modulation achieving the highest efficacy, followed by the sinusoidal rate modulation. The anti-nociceptive effects of sinusoidal rate modulation on EEG outlasted SCS duration on the behavioral and EEG levels. These results suggest that TDP modulation may improve clinical outcomes by reducing pain intensity and possibly improving the sensory experience.

2019 ◽  
Author(s):  
Adnan Al-Kaisy ◽  
Jonathan Royds ◽  
Stefano Palmisani ◽  
David Pang ◽  
Samuel Wesley ◽  
...  

Abstract Introduction Chronic neuropathic low back pain (CNLBP) is a debilitating condition in which established medical treatments seldom alleviate symptoms. There is evidence demonstrating high frequency 10kHz spinal cord stimulation (SCS) reduces pain and improves health-related quality of life in patients with Failed Back Surgery Syndrome (FBSS) but there is limited evidence in CNLBP without prior surgery. The aim of this multicentre randomised trial is to assess the clinical and cost-effectiveness of 10kHz SCS for this population. Methods This is a multicentre double-blind randomised sham-controlled trial with a parallel economic evaluation. A total of 96 patients with CNLBP who have not had spinal surgery will be implanted with an epidural lead and a sham lead outside the epidural space without a screening trial. Patients will be randomised 1:1 to 10kHz SCS plus usual care (intervention group) or sham 10kHz SCS plus usual care (control group) after full implant. The SCS devices will be programmed identically using a cathodal cascade. Participants will use their handheld programmer to alter the intensity of the stimulation as per routine practice. Primary outcome will be a 7 day daily pain diary. Secondary outcomes include the Oswestry Disability Index, complications, EQ-5D-5L, and health and social care costs. Outcomes will be assessed at baseline (pre-randomisation) and at 1 month, 3 months and 6 months after device activation. The primary analyses will compare primary and secondary outcomes between groups at 6-months adjusting for baseline outcome scores. Incremental cost per quality adjusted life year (QALY) will be calculated at 6-months and over the patient lifetime. Discussion The outcomes of this trial will inform clinical practice and healthcare policy on the role of high frequency 10kHz SCS for patients with CNLBP without prior surgery.


2013 ◽  
Vol 119 (2) ◽  
pp. 422-432 ◽  
Author(s):  
Ronen Shechter ◽  
Fei Yang ◽  
Qian Xu ◽  
Yong-Kwan Cheong ◽  
Shao-Qiu He ◽  
...  

Abstract Background: Spinal cord stimulation (SCS) is a useful neuromodulatory technique for treatment of certain neuropathic pain conditions. However, the optimal stimulation parameters remain unclear. Methods: In rats after L5 spinal nerve ligation, the authors compared the inhibitory effects on mechanical hypersensitivity from bipolar SCS of different intensities (20, 40, and 80% motor threshold) and frequencies (50, 1 kHz, and 10 kHz). The authors then compared the effects of 1 and 50 Hz dorsal column stimulation at high- and low-stimulus intensities on conduction properties of afferent Aα/β-fibers and spinal wide-dynamic–range neuronal excitability. Results: Three consecutive daily SCS at different frequencies progressively inhibited mechanical hypersensitivity in an intensity-dependent manner. At 80% motor threshold, the ipsilateral paw withdrawal threshold (% preinjury) increased significantly from pre-SCS measures, beginning with the first day of SCS at the frequencies of 1 kHz (50.2 ± 5.7% from 23.9 ± 2.6%, n = 19, mean ± SEM) and 10 kHz (50.8 ± 4.4% from 27.9 ± 2.3%, n = 17), whereas it was significantly increased beginning on the second day in the 50 Hz group (38.9 ± 4.6% from 23.8 ± 2.1%, n = 17). At high intensity, both 1 and 50 Hz dorsal column stimulation reduced Aα/β-compound action potential size recorded at the sciatic nerve, but only 1 kHz stimulation was partially effective at the lower intensity. The number of actions potentials in C-fiber component of wide-dynamic–range neuronal response to windup-inducing stimulation was significantly decreased after 50 Hz (147.4 ± 23.6 from 228.1 ± 39.0, n = 13), but not 1 kHz (n = 15), dorsal column stimulation. Conclusions: Kilohertz SCS attenuated mechanical hypersensitivity in a time course and amplitude that differed from conventional 50 Hz SCS, and may involve different peripheral and spinal segmental mechanisms.


Neurosurgery ◽  
2011 ◽  
Vol 68 (5) ◽  
pp. 1452-1461 ◽  
Author(s):  
Jan Holsheimer ◽  
Jan R. Buitenweg ◽  
John Das ◽  
Paul de Sutter ◽  
Ljubomir Manola ◽  
...  

Abstract BACKGROUND: In spinal cord stimulation for the management of chronic, intractable pain, a satisfactory analgesic effect can be obtained only when the stimulation-induced paresthesias cover all painful body areas completely or partially. OBJECTIVE: To investigate the effect of stimulus pulse width (PW) and contact configuration (CC) on the area of paresthesia (PA), perception threshold (VPT), discomfort threshold (VDT), and usage range (UR) in spinal cord stimulation. METHODS: Chronic pain patients were tested during a follow-up visit. They were stimulated monopolarly and with the CC giving each patient the best analgesia. VPT, VDT, and UR were determined for PWs of 90, 210, and 450 microseconds. The paresthesia contours at VDT were drawn on a body map and digitized; PA was calculated; and its anatomic composition was described. The effects of PW and CC on PA, VPT, VDT, and UR were tested statistically. RESULTS: Twenty-four of 31 tests with low thoracic stimulation and 8 of 9 tests with cervical stimulation gave a significant extension of PA at increasing PW. In 14 of 18 tests (low thoracic), a caudal extension was obtained (primarily in L5-S2). In cervical stimulation the extension was predominantly caudal as well. In contrast to VPT and VDT, UR is not significantly different when stimulating with any CC. CONCLUSION: PA extends caudally with increasing PW. The mechanism includes that the larger and smaller dorsal column fibers have a different mediolateral distribution and that smaller dorsal column fibers have a smaller UR and can be activated only when PW is sufficiently large. A similar effect of CC on PA is unlikely as long as electrodes with a large intercontact distance are applied.


Neurosurgery ◽  
1988 ◽  
Vol 22 (4) ◽  
pp. 707-714 ◽  
Author(s):  
Herman Hugenholtz ◽  
Peter Humphreys ◽  
William M. J. McIntyre ◽  
Robert A. Spasoff ◽  
Kate Steel

Abstract A prospective double-blind study of high cervical spinal cord stimulation conducted in eight moderately disabled, spastic, cerebral palsied children failed to demonstrate any significant improvement over base line function during chronic spinal cord stimulation at either optimal stimulation parameters or random placebo parameters. Chronic stimulation included 4 consecutive months of stimulation for 24 hours each day. Stimulators were randomly programmed at optimal parameters for 2 of the 4 months and at placebo parameters for the remaining 2 months. At the end of each month of chronic stimulation, subjects were assessed with a multidisciplinary test battery that included a self-assessment, specific clinical examinations, tests of gross and fine motor control, neuropsychological and neurophysiological tests, a detailed gait analysis, and video recordings. By 6 months after the completion of the study, only 1 of the 8 subjects continued to use his stimulator on a regular basis, with minimal benefit.


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