Chronic pain is the most prevalent disease worldwide and often non-specific, which means that there is no underlying pathology or enough tissue damage to explain the pain experience. Often, people with chronic pain have a high sensitivity of the nervous system, called “central sensitization” (CS). CS is considered as an “amplification of neural signalling within the central nervous system that elicits pain hypersensitivity” (Nijs et al, 2021). This can lead to developing nociplastic pain, a category separate from mechanical inflammatory pain, tissue damage and neuropathic pain (caused by a lesion of part of the nervous system). Having CS means suffering from hypersensitivity to non-musculoskeletal stimuli, such as chemical substances, light, touch, sound, heat, cold, stress, to name a few. CS has been identified in subgroups of people suffering from musculoskeletal syndromes, low back pain, and chronic fatigue syndrome.
Recently, the International Association for the Study of Pain (IASP) has released clinical criteria and a grading system for nociplastic pain (of which CS is the underlying mechanism) affecting the musculoskeletal system, which are:
1) report of pain of at least 3 months duration;
2) report of a regional rather than discrete (specific) pain distribution;
3) report of pain that cannot entirely be explained by nociceptive or neuropathic mechanisms
4) show clinical signs of pain hypersensitivity.
Also, IASP suggests that if these four requirements are met, and the person has at least one comorbidity of the following: increased sensitivity to sound, light and/or odours, sleep disturbance with frequent nocturnal awakenings, fatigue or cognitive problems (e.g. concentration or memory), then the problem is defined as “probable nociplastic pain” rather then nociceptive (inflammatory, mechanical or related to tissue damage).
As you can see from the report above, the advances in understanding the nature or chronic pain is taking clinicians in looking at body pain as part of a cluster of symptoms. For this reason, the treatment of pain has to be delivered with consideration of other symptoms too and, therefore, needs a more holistic nervous-system based (e.g. body-mind) approach, where body strategies and tailored exercises (bottom-up) are integrated with mind/cognitive approaches (top down). In our practice, we use this integrated approach which is considered the best practice in musculoskeletal disorders associated with CS symptoms.
As these concepts are not straightforward and require some explanations and understanding, I’ve decided to run every couple of months a FREE INTRODUCTORY SESSION TO PAIN MANAGEMENT (see in the "Events" section on the bar above) to discuss the difference between acute, chronic, nociceptive and nociplastic pain, but also what Pain Management is and why is needed in more complex pain conditions. I’ll also be able to answer your questions, so please come and join me for an interesting and rich hour!
REFERENCES:
Kosek E, Clauw D, Nijs J, Baron R, Gilron I, Harris RE, Mico JA, Rice AS, Sterling M. Chronic nociplastic pain affecting the musculoskeletal system: Clinical criteria and grading system. Pain. 2021 Nov 1;162(11):2629-34.
Nijs J, Lahousse A, Kapreli E, Bilika P, Saraçoğlu İ, Malfliet A, Coppieters I, De Baets L, Leysen L, Roose E, Clark J. Nociplastic pain criteria or recognition of central sensitization? Pain phenotyping in the past, present and future. Journal of clinical medicine. 2021 Jan;10(15):3203.
Nijs J, Van Houdenhove B, Oostendorp RA. Recognition of central sensitization in patients with musculoskeletal pain: application of pain neurophysiology in manual therapy practice. Manual therapy. 2010 Apr 1;15(2):135-41.