Title: Radiofrequency denervation for chronic and moderate to severe low back pain: The RADICAL trial
Funder: Department of Health and Social Care

Abstract: Background_x000D_ Long-term low back pain is common, affecting 10-15% of adults. It can significantly impair the health, mood, and daily lives of people who have it. One type of low back pain is caused by the small joints between the bones in the lower back. Treatments include painkillers, exercise and talking therapies. However, if people do not get better with these treatments, they can be offered radiofrequency “denervation”. Denervation involves placing a needle in the nerve to the painful joint, which is heated up to cause a break in the nerve. The purpose of this is to stop the nerve sending pain messages to the brain. Denervation is low risk and is used widely in the NHS but we do not know if this procedure definitely reduces pain or is a good way to spend NHS money. This study aims to find out if denervation reduces low back pain and is good value for money._x000D_ _x000D_ Design and methods_x000D_ For health professionals to provide the best care for patients, randomized studies are needed to find out if treatments work. A randomized study involves assigning patients by chance to the treatment of interest, or to usual care, so that the effect of the treatment can be compared fairly. In some studies, a treatment is compared to a dummy treatment._x000D_ _x000D_ This study will involve 250 NHS patients who are eligible for denervation in 20 pain management centres and spinal clinics across the UK. Half will have the denervation and half will have a dummy treatment involving placement of the needle in the nerve but without heating it up, so the nerve is not affected. The treatment offered will be decided by chance. All other aspects of care will be the same as the usual care provided by the hospital. Patients, clinicians and researchers will not know which treatment has been given. This is to make sure that no one can influence the results. Patients whose symptoms do not improve after 3 months will be offered the chance to receive the other treatment but without disclosing to the patient or the doctor what treatment was given either the first or second time. This means that patients who had no improvement because they had the dummy treatment first would have the opportunity for real denervation the second time._x000D_ _x000D_ Patients will be asked questions about their low back pain, ability to carry out daily tasks, general health, and mental well-being over the next 2 years. The answers of people who had real denervation will be compared with those of people who had dummy treatment to find out if denervation improves symptoms. Information will also be collected to find out if denervation is good value for money._x000D_ _x000D_ _x000D_ Patient and public involvement (PPI)_x000D_ This study has been developed with our musculoskeletal PPI group. To make sure the views of patients are central to the way the study is done, a new PPI group will be set up for this trial, involving patients with experience of denervation. Regular meetings will be held to discuss design, management and dissemination. Two patient representatives will sit on the Trial Steering Committee._x000D_ _x000D_ Dissemination_x000D_ Findings will be reported and disseminated in a suitable format so that they reach people who can benefit from them. This will include plain English summaries for the public and customised material for other people such as health professionals or NHS Trusts. Team members have links with relevant patient support organisations and will ensure the findings are considered by experts responsible for the National Back Pain Pathway.

Lay abstract: Design: Double-blind, parallel group, superiority RCT with internal pilot, qualitative research and health economic analysis._x000D_ _x000D_ Setting: 20 pain and spinal clinics providing RFD to NHS patients._x000D_ _x000D_ Inclusion criteria: Adults with chronic moderate to severe LBP referred to secondary care after insufficient improvement with NICE recommended conservative management; clinical features suggestive of facet joint involvement; positive response to single diagnostic medial branch block._x000D_ _x000D_ Exclusion criteria: Pregnancy; infection; unwilling or unable to tolerate procedure; psychological barriers to recovery (severe depression or widespread pain); previous RFD; pacemaker or implantable cardioverter defibrillator; malignancy as the reason for LBP_x000D_ _x000D_ Health technologies being assessed: RFD of the lumbar medial branches of the dorsal rami. Using the C-arm of a fluoroscope, a needle will be inserted adjacent to the nerve and an electrode heated to make a RF lesion. Placebo RFD will follow the same protocol, but the electrode tip temperature will not be raised. Prior to commencing the trial, a survey and PI meeting will be undertaken to develop a protocol that specifies the variations in the RFD procedure that will be permitted and prohibited within the trial._x000D_ _x000D_ Blinded re-intervention with alternative treatment: Participants who do not experience a clinically meaningful improvement in pain 3 months after randomization will be offered “repeat RFD” but with the alternative intervention to the one provided at the outset without disclosing the original allocation._x000D_ _x000D_ Measurement of outcomes: The primary clinical outcome will be pain severity, measured using a 0-10 pain NRS, at 3 months after randomization. Secondary outcomes will be functional disability, health-related quality of life, psychological distress, time to pain recovery, satisfaction, frequency of uptake of offer of repeat RFD, adverse events, work outcomes and healthcare utilisation. Pain severity will be assessed at 2, 4, 6, 8 and 10 weeks after randomization, with the EQ-5D-5L at 6 weeks. Questionnaires, assessing all outcomes, will be administered at baseline and at 3, 6, 12, 18 and 24 months after randomization._x000D_ _x000D_ Cost-effectiveness analysis: The primary economic evaluation will take an NHS and social services perspective and estimate the discounted cost per quality adjusted life year and incremental net benefit of RFD over the 2 year follow up period. Cost-effectiveness acceptability curves will estimate the probability of cost-effectiveness at different values of willingness-to-pay. In secondary analyses we will estimate cost-effectiveness at 3 month follow up and include patient costs and productivity gains/losses in a societal perspective 2 year analysis._x000D_ _x000D_ Sample size: Assuming that scores at 3 months will be adjusted for baseline scores, with a correlation of 0.3 between scores, a sample size of 226 participants is required to detect the target difference of 0.84 in the NRS with 90% power and 5% 2-tailed significance (standard deviation 2; standardised difference=0.42). Allowing for up to 10% attrition at 3 months gives a total of 250 participants (125 per group). _x000D_ _x000D_ Project timetable: 60 months comprising 9 months set up, 18 months recruitment (including 12 month pilot), 25 months follow-up, and 8 months data analyses and reporting.

Research activity codes: 6.4 SURGERY
Health categories: MUSCULOSKELETAL