Study protocol: Effects of active versus passive recharge burst spinal cord stimulation on pain experience in persistent spinal pain syndrome type 2: a multicentre randomized trial (BURST-RAP study).

BACKGROUND: Spinal cord stimulation (SCS) has shown to be an effective treatment for patients with persistent spinal pain syndrome type 2 (PSPS Type 2). The method used to deliver electrical charge in SCS is important. One such method is burst stimulation. Within burst stimulation, a recharge pattern is used to prevent buildup of charge in stimulated tissues. Two variations of burst waveforms are currently in use: one that employs active recharge and one that uses passive recharge. It has been suggested that differences exist between active and passive recharge paradigms related to both efficacy of pain relief and their underlying mechanism of action. Active recharge has been shown to activate both the medial spinal pathway, engaging cortical sensorimotor areas involved in location and intensity of pain, and lateral pathway, reaching brain areas involved with cognitive-emotional aspects of pain. Passive recharge has been suggested to act via modulation of thalamic neurons, which fire in a similar electrical pattern, and thereby modulate activity in various cortical areas including those related to motivational and emotional aspects of pain. The objective of this randomized clinical trial is to assess and compare the effect of active versus passive recharge Burst SCS on a wide spectrum of pain in PSPS Type 2 patients. METHODS: This multicentre randomized clinical trial will take place in 6 Dutch hospitals. PSPS Type 2 patients (n=94) will be randomized into a group receiving either active or passive recharge burst. Following a successful trial period, patients are permanently implanted. Patients complete the Pain Catastrophizing Scale (PCS) (primary outcome at 6 months), Numeric Pain Rating Scale (NRS), Patient Vigilance and Awareness Questionnaire (PVAQ), Hospital Anxiety and Depression Scale (HADS), Quality of Life (EQ-5D), Oswestery Disability Index (ODI), Patient Global Impression of Change (PGIC) and painDETECT questionnaires (secondary outcomes) at baseline, after trial, 1, 3, 6 and 12 months following implantation. DISCUSSION: The BURST-RAP trial protocol will shed light on possible clinical differences and effectivity of pain relief, including emotional-motivational aspects between active and passive burst SCS in PSPS Type 2 patients. TRIAL REGISTRATION: ClinicalTrials.gov registration:  NCT05421273 . Registered on 16 June 2022. Netherlands Trial Register NL9194. Registered on 23 January 2021.

Dutch Consensus Paper: A Consensus View on the Place of Neurostimulation Within the Treatment Arsenal of Five Reimbursed Indications for Neurostimulation in The Netherlands.

INTRODUCTION: After an interpretation trajectory, the Dutch Quality of Healthcare Institute recommended that for five indications, spinal cord stimulation, dorsal root ganglion stimulation, or occipital nerve stimulation, together referred to as neurostimulation, can be considered effective and be reimbursed in the Netherlands. These five indications are the well and largely studied, accepted neurostimulation indications in scientific literature. As an extension of this, all the scientific societies involved in the Netherlands were required to reach a consensus about the diagnosis and treatment of these five formulated indications to describe the place of neurostimulation within the treatment algorithm. This article describes the development process and content of the consensus paper. MATERIALS AND METHODS: A scientific committee, consisting of three anesthesiologists/pain physicians (one of whom acted as the working group's chair), a neurosurgeon, a neurologist, a rehabilitation physician, and three nurse practitioners, participated. A quality advisor of the Knowledge Institute of the Dutch Federation of Medical Specialists supported the committee. The committee participated on behalf of their various scientific and professional societies. Three sessions were organized during which the place of neurostimulation in the treatment algorithm of the five relevant indications was discussed extensively. A narrative literature review and experts' opinions formed the basis of decision-making in the process. RESULTS: For all five diagnoses, general and diagnosis-specific treatment requirements, conservative treatments, and minimally invasive treatments are listed. These treatments should be considered in the chronic pain management algorithm before eventually proceeding to neurostimulation. DISCUSSION/CONCLUSION: The content of this consensus view was discussed and compared with other literature on cost-effectiveness and the place in the algorithm of treating chronic pain. This Dutch consensus paper could ultimately contribute to the maintenance or expansion of neurostimulation and the reimbursement.

A Prospective Study of Dorsal Root Ganglion Stimulation for Non-Operated Discogenic Low Back Pain.

INTRODUCTION: Disruptions of lumbar intervertebral discs may lead to severe discogenic low back pain (LBP). Severe pain has a deleterious effect on physical function and quality of life. Spinal cord stimulation (SCS) is a robust treatment for many neuropathic pain conditions. New innovations may be well-suited to treat neuropathic chronic LBP, including discogenic pain. The aim of this prospective study was to determine the effect of dorsal root ganglion (DRG) stimulation for a well-selected group of patients with discogenic LBP with no history of previous back surgeries. METHODS: Twenty subjects with confirmed discogenic LBP and no prior history of back surgery underwent trials of DRG stimulation and, if successful with at least 50% pain reduction, were permanently implanted. Subjects rated their pain, disability, quality of life, and mood at baseline, and 14 subjects were followed through 12 months of treatment. RESULTS: Treatment with DRG stimulation reduced LBP ratings (68.3% reduction), from mean 7.20 ± 1.3 at baseline to 2.29 ± 2.1 after 12 months (p = < 0.001). Oswestry ratings of disability significantly decreased (p = < 0.001) from 42.09 ± 12.9 at baseline to 21.54 ± 16.4 after six months of treatment and to 20.1 ± 16.6 after 12 months. The average quality of life EQ-5D index score at baseline was 0.61 ± 0.12 and 0.84 ± 0.13 after 12 months. DISCUSSION: DRG stimulation treatment for discogenic LBP improved the level of pain, function, and quality of life. Further research is necessary into efficacy of DRG stimulation in patients with chronic discogenic LBP and to determine the place of SCS in the treatment algorithm.

High-Frequency Spinal Cord Stimulation and Pregnancy: A Case Report.

INTRODUCTION: High-frequency spinal cord stimulation (HF SCS) is a relatively new modality of SCS. The present general advice concerning pregnancy and SCS, in general, is to turn the device off because of insufficient knowledge concerning the impact on the developing fetus. As HF stimulation generates higher energies, potential adverse fetal effects could be theoretically stronger. CASE: This case report describes a 36-year-old woman who had two pregnancies with an active HF SCS system. Her first pregnancy ended in a miscarriage. During her second pregnancy, she continued stimulation treatment during the whole pregnancy. She gave birth to a healthy baby. CONCLUSIONS: This case describes both a miscarriage and the birth of a healthy baby in a patient treated with HF SCS. It is not possible to rule out that the HF SCS could have caused the miscarriage. Also, the birth of the healthy baby after the second pregnancy in which HF SCS was used the whole period, is not a valid reason to declare HF SCS and SCS, in general, safe during pregnancy. As no sufficient data are available, we must remain cautious about any unknown possible adverse effects or delayed adverse events because of SCS and maybe especially HF stimulation. All outcome data on pregnancies during all types of SCS ideally should be collected and analyzed.