Dr Serge Nikolic
Consultant in pain medicine and Neuromodulation, Clinical lead for Neuromodulation, St Bartholomew’s Hospital and The Royal London Hospital
Dr Sarah Love-Jones
Consultant in Pain Medicine and Anaesthesia and Lead Clinician for Spinal Cord Stimulator Service in the Pain Clinic, North Bristol NHS Trust
Dr Ashish Gulve
Clinical Lead Consultant in Pain Management, The James Cook University Hospital
A new type of spinal cord stimulation technology is improving the quality of life for selected neuropathic pain patients. Is this a breakthrough in chronic pain management?
Chronic pain is a much bigger problem than most people realise, notes Dr Serge Nikolic, Consultant in Pain Medicine and Neuromodulation, and Clinical Lead for Neuromodulation at St Bartholomew’s Hospital and The Royal London Hospital.
“For the 550 million people around the world who live with chronic pain, the consequences are far-reaching,” he says. “It can limit an individual’s day-to-day function, mobility and quality of life, and in extreme cases lead to isolation, loneliness and complete withdrawal of social interaction, which has an enormous impact on family life. A person with chronic pain may be unable to work, which can cause financial and mental health issues; plus, their complex needs can place a profound economic burden on welfare and healthcare systems. So, any treatment that can improve chronic pain is to be welcomed by those affected — and by society as a whole.”
“Thankfully, a treatment called spinal cord stimulation (SCS) can be effective in reducing this pain. SCS therapy uses a small, implanted device that transmits electrical pulses to the spine and in doing so selectively intercepts chronic pain signals travelling to the brain. In most cases this results in a significant improvement in function, mobility, sleep and overall quality of life” says Dr Nikolic.
Improving neuropathic pain long term
Dr Sarah Love-Jones, Consultant in Pain Medicine and Anaesthesia and Lead Clinician for Spinal Cord Stimulator Service in the Pain Clinic at North Bristol NHS Trust, cautions that it won’t benefit all chronic pain patients. “For example, SCS isn’t suitable for those with mechanical back pain or fracture pain,” she says. “This is why potential candidates should first be assessed by a team of multidisciplinary specialists.” Those who could benefit from SCS therapy include patients who have undergone technically successful back or leg operations, but still experiencing significant back, leg or arm pain.
SCS was developed over 50 years ago and has been proven safe and effective in treating chronic pain yet it still has it limitations. Unlike a similar technology used to treat cardiac dysfunction, all therapies currently stimulate the spinal cord without listening to the signals that return. Cardiac pacemakers use electrocardiograms to control a patient’s therapy. In SCS, there has not been such a parallel and all systems are open-loop and fixed-output. The patient has to manually adjust their therapy based on subjective feedback.
A new SCS system is available, which overcomes these limitations. The new closed-loop system is the only SCS system designed to measure the spinal cord’s response to stimulation in the form of the evoked compound action potential (ECAP) and make automatic, real-time adjustments millions of times per day. For the first time, the system delivers consistent therapy so that patients can focus less on their pain and return to living life, sleeping better, and potentially reduce their medications.
Benefits of closed-loop SCS therapy
Dr Ashish Gulve, Clinical Lead Consultant in Pain Management at The James Cook University Hospital in Middlesbrough, carried out the first closed-loop implant in the UK when it became commercially available 18 months ago. “The patient was a young lady who had a young family and was taking three different types of painkilling medication,” he says. “Before the implant she scored her pain as a six to seven out of 10 — if 10 is the worst pain you can think of. Yet a year after her implant she was reporting excellent pain relief, with a pain score of zero to one out of 10, and experienced an improvement in her overall quality of life.”
Closed-loop spinal cord stimulation provides a lot of optimism for the future of managing chronic pain. Dr Nikolic says: “This is the first time that we can observe the spinal response to this therapy and, more importantly, automatically adjust the treatment so it is kept at its optimum level that patients find helpful long term. We at Barts have now implanted more than 20 patients over the past year with very promising results.”
He says: “The closed-loop spinal cord stimulation treatment is available on the NHS and the service can be accessed through appropriate GP or secondary care referrals.”
The Evoke® Closed-Loop System is the first and only closed-loop spinal cord stimulation system. In a recent NICE briefing, comments from clinical experts suggested Evoke could reduce hospital follow-up visits because of improved pain management over time, reduce the use of pain management medication and reduce the reliance of clinicians on subjective feedback from patients.