Overview:
ASPN UPDATED guidelines for physicians using neuromodulation products and techniques to manage chronic pain.
The American Society of Pain and Neuroscience (ASPN) has just issued UPDATED guidelines for physicians using neuromodulation products and techniques to manage chronic pain.
The updated guidelines appear in the February 3, 2025, issue of the Journal of Pain Research under the title: “The American Society of Pain and Neuroscience (ASPN) Guidelines and Consensus on the Definition, Current Evidence, Clinical Use and Future Applications for Physiologic Closed-Loop Controlled Neuromodulation in Chronic Pain: A NEURON Group Project.”
But, of course, we have a summary here.
37 Centers, Global Input
Not only were the guidelines comprehensive—covering the safety, efficacy and taxonomy of physiologic closed loop controlled systems—but the authors assembled a global network of 37 centers to contribute.
The FDA defines physiologic closed loop controlled systems as: “…a system consisting of sensors, actuators, and control algorithms that adjusts or maintains a physiologic variable through automatic adjustments to delivery or removal of energy or article (e.g., drugs, or liquid or gas regulated as a medical device) using feedback from a physiologic-measuring sensor(s).”[i]
Timothy Deer, M.D., chairman and founder of the American Society of Pain and Neuroscience, explained to OTW that one of the issues practitioners face with these closed loop controlled systems is variability and loop quality. “The issue is systems differ in the quality of the loop. This technology arose from cochlear systems that allowed hearing in those who were deaf.”
“Some neuro systems measure and respond 40 times a second while others do much less often. Both are called closed loop and in the same category, but they may not have the same response. Currently, there are two current systems in the neurostimulation market, and both appear to be growing at a relatively fast pace. Long-term consistent outcomes will be the measure if this continues.”
OTW asked Dr. Deer why it has been “extremely difficult” to achieve consistent, reliable, and therapeutic neural activation of the spinal cord.
“In current systems the amount of electricity and the response has been impossible to measure. In some settings such as paresthesia-free systems this may not be a major issue, but with closed loop level one evidence (EVOKE, Saluda Medical) does show consistent ability to stay in the therapeutic window with neural activation measured several times a second,” he said.
Four Supporting Studies
Dr. Deer, who is also president and CEO of The Spine and Nerve Center of The Virginias and clinical professor of Anesthesiology and Pain Medicine at the West Virginia University School of Medicine, noted that one of the areas of concern is, in fact, how people interact with this type of novel technology.[ii]
The authors cited four pivotal studies in their guidelines: “The evidence for continuous physiologic closed loop controlled systems spinal cord stimulation is supported by a 2-year multicenter observational study (AVALON), a one-year multicenter observational study (ECAP) and a three-year randomized, multicenter double-blinded, self-selected crossover RCT (EVOKE).”
“This represents Level 1A evidence and a high degree of certainty, yielding a GRADE A consensus for improvement in pain intensity, sleep, function, mood, and quality of life.”
“Currently, there is only one FDA-approved spinal cord stimulation therapy that offers closed loop stimulation with published 12-month data. The patient population most studied, with published results, is for back and leg pain. More research is needed on different chronic pain indications.”
“Physiologic closed loop controlled neuromodulation is an innovation that requires a responsible introduction. As commercial access grows, there is a responsibility that requires consistency with definition, evidence generation, focused on safety and efficacy. The American Society of Pain and Neuroscience is committed to survey the safety, efficacy, and evidence of physiologic closed loop controlled neuromodulation, with periodic updates planned to update this live document.”
Disclosure: Dr. Deer is a consultant to Abbott and Saluda.
[i] United States Food and Drug Administration (FDA), Health and Human Services. Technical Considerations for Medical Devices With Physiologic Closed-Loop Control Technology; Guidance for Industry and Food and Drug Administration Staff. 2023. Available from:https://www.fda.gov/regulatory-information/search-fda-guidance-documents/technical-considerations-medical-devices-physiologic-closed-loop-control-technology. Accessed December 27, 2024.
[ii] Lee JD. Review of a pivotal human factors article: “Humans and automation: use, misuse, disuse, abuse”. Hum Fact. 2008;50(3):404–410. doi: 10.1518/001872008X288547
