Friday, September 23rd
1:30pm-3:00pm EDT


Topical Workshop


Assessment, Diagnosis & Measurement of Pain


717 A

Conditioned Pain Modulation (CPM): To Be or Not To Be?

This house believes that conditioned pain modulation (CPM) is a useful tool for research and clinical work. This is based on many studies showing less efficient CPM in pain patients, especially in the nociplastic disorders, and on studies that show prediction by CPM of future pain after interventions such as surgery as well as response to pain treatment. Nevertheless, many studies show difficulties in test repeatability, and a lack of relevance of CPM to those clinical situations. In this debate the first opponent will review the data supporting the relevance of CPM, and the other opponent will review the data against. The discussion will attempt to put in order the available data, and draw some conclusions regarding the role of CPM in clinical research and clinical practice


1:30pm EDT3:00pm EDT

Conditioned Pain Modulation is Associated with Reliability Issues, Problems with Generalizability and Lacks Clinical Predictability

Tracks: Assessment, Diagnosis & Measurement Of Pain
Categories: Topical Workshop

Conditioned pain modulation (CPM) can be assessed using a wide range of test modulates with different test-retest capabilities. Studies indicate that multiple factors such as sleep deprivations, opioid use and cognitive factors will impact the assessment. These factors are rarely controlled for, which comprises the test-retest reliability. Recent studies demonstrate that the temporal summation of pain (TSP) and CPM response in patients with chronic pain varies, which could be interpreted as some patients being more pain sensitive than others. Pretreatment TSP variability seems to independently predict treatment responses to standard pain treatments such as surgery, NSAIDs and exercise therapy and this seems to be a less consistent finding for CPM. Finally, the descending pain inhibitory pathways are serotonin- and noradrenalin-dependent. Studies have demonstrated that CPM predict the analgesic effect of duloxetine (a serotonin and noradrenalin reuptake inhibitory) and that duloxetine modulates CPM. Dr. Petersen and colleagues recently conducted an 18-weeks randomized placebo-controlled trial on duloxetine in patients with severe knee osteoarthritis and found no effects CPM and CPM did not predict the analgesic effect of duloxetine. Conclusively, these data suggest that CPM is unfit as a biomarker in clinical trials and suggest that research initiatives should be directed towards TSP.

1:30pm EDT3:00pm EDT

Conditioned Pain Modulation is a Real Physiological Phenomenon: Evidence for a Spinal Neuronalcorrelate in Translational Studies

Tracks: Assessment, Diagnosis & Measurement Of Pain
Categories: Topical Workshop
Presented By: Dr. Kirsty Bannister

The ‘pain inhibits pain’ phenomenon was originally described in anesthetized rodents, where it is possible to quantify functionality in the pathway – scientifically termed diffuse noxious inhibitory controls (DNIC) - as a decrease in the peripherally-evoked activity of spinal convergent neurons following application of a conditioning stimulus. Interestingly, such naturally occurring analgesia upon conditioning is also observed in conscious humans, and conditioned pain modulation (CPM) is the term coined by Professor Yarnitsky to describe the human counterpart of DNIC. The functionality of this system depends on multiple factors including attention to the test and/or conditioning stimulus, distraction, and mood among others. But at the heart of the pain inhibits pain phenomenon, whether being measured in wakeful humans or anesthetized rats, is a brainstem to spinal cord modulatory pathway that is sub-served by noradrenaline to reduce pain signal processing in the transmission center. This is clinically relevant since pharmacotherapies that restore an imbalance in monoaminergic transmission, such as duloxetine and tapentadol, have previously been shown to restore CPM in chronic pain patient populations. Crucially therefore, CPM is possible to apply as a biomarker in clinical trials if the patient cohort, and stratification therein, is accurately described.


Professor David Yarnitsky

Professor and Chair,
Rambam Med Ctr and Technion Faculty of Medicine

Dr. Kirsty Bannister

Associate Professor
King's College London

Kristian Kjaer Petersen

Associate Professor
Aalborg University