Boston Virgin Back Study
Research type
Research Study
Full title
A prospective single centre pilot study to investigate the response to 1000Hz frequency in patients with spinal cord stimulation with intractable neuropathic pain who have not undergone spinal surgery (virgin back).
IRAS ID
233381
Contact name
Vivek Mehta
Contact email
Sponsor organisation
Barts Health NHS Trust
Duration of Study in the UK
1 years, 9 months, 30 days
Research summary
Lay summary of study results: Although SCS is a successful treatment for PSPS Type-1, the evidence is evolving and is limited by long term data and quality of life outcomes. Additionally, there is a need to identify underlying pathology in this cohort based on imaging studies, that may contribute in failure of therapy. Based on the fact of intricate spine anatomy inclusive bony, ligamentous and nerve components, this evaluation can be extremely useful in predicting potential responders, particularly in the current perspective of increasing appetite for SCS use in non-surgical back pain patients. The primary objective of the study was to investigate the clinical response following neurostimulation in patients with lumbar PSPS type 1. The secondary objective of the study was to investigate the effect on functionality, quality of life, sleep index and adverse events in the study population.
MethodsPatients with intractable neuropathic pain PSPS type 1 (n=30) were recruited (2019- 22) in a single tertiary neuromodulation centre to undergo SCS (BSC Wavewriter Alpha, dual 16 contact Infinion leads) direct to implant with anatomical placement at T9-T10 . All patients underwent mandatory 1000Hz frequency stimulation until the primary end point (12 weeks) followed by real world waveforms as deemed suitable with patient and clinician compliance. Numerical rating score (NRS) and data from self-report questionnaires (Oswestry Disability Index (ODI), Pain and Sleep Questionnaire (PSQ), Patient Global Impression of Change), EQ-5D-5L were collected pre-implant and at 4 weeks, 12 weeks, 6 months, 12 months and 24 months post-implant. All implanted patients underwent MRI imaging preoperatively and images reviewed by independent radiologist in all explants/failures to identify any contributing factors.
Results
The average NRS for back and leg improvement at 4 weeks (n=28) -49% and -54% vs. baseline; at 12 weeks (n=27) -43% and -55% vs. baseline; at 6 months (n=22) -50% and -61% vs. baseline; at 12 months (n=19), - 46% and -52% vs. baseline; at 24 month (n=13),-50% and -51% vs. baseline. ODI scores at 12 months 42.47±25.86 (-23% vs. baseline), and 24 months 38.55±23.14 (-30% vs. baseline) were reported.
Findings
Spinal Cord Stimulation is proving to be an effective treatment for people with persistent pain after back surgery (called Post-Surgical Pain Syndrome or PSPS). It helps relieve both back and leg pain, allowing patients to reduce their use of pain medications, especially opioids. This treatment not only eases pain but also improves daily functioning and quality of life. The success of SCS depends on carefully selecting the right patients, making sure their condition is fully understood, and assessing their readiness for the procedure. When used appropriately, SCS can lead to significant improvements in pain relief, medication reduction, and overall well-being. Although this long-term follow-up supports the clinical benefit of SCS up to 50% at 24 months in PSPS Type-1, there remains a need to identify patients that are poor responders in this cohort. This can potentially help in improving patient selection criteria within this group of population.
Spinal Cord stimulation (SCS) is a common intervention used in patients who suffer from chronic nerve pain following back surgery. This is known as failed back surgery syndrome (FBSS). Equally, the National Institute of Clinical Excellence (NICE) who work with the NHS, recommend suitable medicines and treatments for patients in their guidelines; suggest that SCS can be used in patients who have never had back surgery. The is no outcome data to define that SCS works in patients with neuropathic back pain, therefore this study will provide clinical data to see if this works.
SCS delivers mild electrical impulses to the nerves along the spinal cord. This blocks the pain pathway from reaching the brain. This helps manage the pain experienced the lower back.
SCS consists of three components:
1. Implantable pulse generator (IPG): this is a battery power source that provides the electrical pulses according to set programmes and delivering different frequencies at a set current.
2. Lead: A set of thin wires; one end connected to the IPG and the other end is inserted along the spinal cord. The wires have electrodes near the tips. These electrodes transfer electrical pulses to area of stimulation site.
3. External controller: A remote that controls the settings and programmes of the IPG.
A common side effect of the conventional system is that patients may experience ‘pins and needles’, tingling, numbness, known as parathesia at site of stimulation. This can be particularly uncomfortable for patients. However, parathesia can be eliminated by changing certain settings on the stimulator. This could include increasing the frequency of the stimulator known as high density (HD) frequency. This works by delivering energy to site of stimulation below the parathesia threshold, so minimal or no parathesia is experienced.
Only one study has been completed previously using HD frequency on patients with FBSS. The major findings from these studies have found that when compared to conventional SCS (uses a frequency of 40-80 Hz) that HD frequency has provided better pain relief with minimal or no parathesia. However, these settings have not been done in patients who suffer from neuropathic pain and have not had any previous spinal surgery
REC name
London - London Bridge Research Ethics Committee
REC reference
18/LO/0365
Date of REC Opinion
24 May 2018
REC opinion
Further Information Favourable Opinion