The terminology “acute/chronic” pain is often misinterpreted and is largely misunderstood by many laymen and some clinicians. The primary difference between acute and chronic pain is in the “relatively arbitrary time posts” (Apkarian et al.). In other words, the main difference is in the duration of the pain experience; it does not say anything concrete about a substantial difference in the underlying mechanisms!

Clinicians and patients often misunderstand the difference between chronic pain and acute pain in various ways. In people with chronic pain, the word “chronic” is often interpreted as being very severe and incurable. As noted by Barker et al., most people with chronic pain “felt that chronic meant that the condition was very severe. To some is suggested that the pain was incurable. Chronic means absolute, the pits. Couple of steps from a wheelchair.”



This is in stark contrast to the correct meaning, as noted by Apkarian et al. “The standard definition of chronic pain endorsed by the International Association for the Study of Pain states that it is pain that persists past the healing phase following an injury”. ICE-11 (Treede et al.) defines chronic pain as pain “that lasts or recurs for more than 3 to 6 months” or pain that lasts above 12 weeks (Hainline et al.).

However, clinicians misinterpreted chronic pain on a whole ’nother level. They often think that acute/chronic pain is two distinct and separate clinical entities; they are not. A patient’s pain does not all of a sudden undergo metamorphosis when they have had pain in 2 months and 28 days, and crossover to the “chronic” stage. Nonetheless, many clinicians will act as chronic and acute should be treated as separate clinical entities. This misunderstanding is a specific topic in my courses, lectures, and social media. One typical questions exemplify it: “Does this also apply to acute pain” or vice versa. Regarding the notion of “acute/chronic” pain, pain is pain!

Some clinicians even make statements suggesting that modern pain research, explain pain and therapeutic neuroscience education (TNE) has their place in the case of chronic pain, but not in the case of acute pain. This could not be further from the truth.  As noted by Dr. Bronnie L. Thompson (PhD) “All people experience pains as biopsychosocial experiences, no matter what the origin”.

Even in the case of acute pain, knowledge of modern pain research can potentially increase the quality of care, as evident in the statement made by Linton et al.: “Pain has clear emotional and behavioral consequences that influence the development of persistent problems and the outcome of treatment.” 
. Emotional aspects are often most pronounced in people living with chronic pain. Nevertheless, clinical expertise in the psychology of pain and competence in pain research can markedly improve the quality of care; with people in acute pain as well (Hansen et al.)

.

As I have noted before, if you are advising or providing care for a person in pain or living with chronic pain, you need to have a firm grasp of current pain research. An in-depth understanding of pain’s complexity, the qualitative experience of being in pain, and definitively knowledge of the many different factors that modulate pain should be essential skills.

Combined, these can serve as a fundamental and robust starting point for a modern approach to provide care for people with pain. If you are trying to help people who have pain, “pain science” and pain research should be an integral part of your clinical vocabulary. 

This is no different than if you are trying to help people with cardio-respiratory, psychological or neurological disorders; you should have a firm grasp of the current research about the optimal care of the particular disease that you are treating and the people you are taking responsibility for helping.

To rephrase it in a more direct way: if you are providing care for people with neurological diseases, you should have a firm grip on that discipline and relevant subfields. This same standard applies to providing care for people living with pain. So “pain science” is really about applying a scientific, research-based approach to understanding pain and optimizing the rehabilitation and management of people living with pain.

Let me end this article by quoting an editorial by Prof. John D. Loeser (MD) on this very topic.

“The idea that acute pains transition into chronic is without an evidential underpinning and, I believe, is an error in conceptualization [3]. There is no known physiologic or anatomic change that occurs at 3 or 6 months after onset of a painful condition. Utilizing duration as a critical factor may obscure the role of other factors such as affective state, coping strategies and past history in perpetuating chronic pain.” Loeser 2018

Dr. John D. Loeser is Professor emeritus of Neurological Surgery and Anesthesiology and Pain Medicine. He is the former Director of the Multidisciplinary Pain Center at the University of Washington.  Prof. Loeser has been active in pain-research and the field of Pain Management for over 45 years. He is the Past President of the American Pain Society and the International Association for the Study of Pain.

 

References: 



Apkarian AV, Baliki MN, Geha PY. Towards a theory of chronic pain. Prog Neurobiol. 2009 Feb;87(2):81-97. Epub 2008 Oct 5. 



Barker KL, Reid M, Minns Lowe CJ. Divided by a lack of common language? A qualitative study exploring the use of language by health professionals treating back pain. BMC Musculoskelet Disord. 2009 Oct 5;10:123. 



Hainline B, Derman W, Vernec A, Budgett R, Deie M, Dvořák J, Harle C, Herring SA, McNamee M, Meeuwisse W, Lorimer Moseley G, Omololu B, Orchard J, Pipe A, Pluim BM, Ræder J, Siebert C, Stewart M, Stuart M, Turner JA, Ware M, Zideman D, Engebretsen L. International Olympic Committee consensus statement on pain management in elite athletes. Br J Sports Med. 2017 Sep;51(17):1245-1258.



Hansen GR, Streltzer J. The psychology of pain. Emerg Med Clin North Am. 2005 May;23(2):339-48.

Linton SJ, Shaw WS. Impact of psychological factors in the experience of pain. Phys Ther. 2011 May;91(5):700-11. Epub 2011 Mar 30.

Loeser JD. A new way of thinking about pain. Pain Manag. 2019 Jan 1;9(1):5-7. Epub 2018 Dec 5.

Treede RD, Rief W, Barke A, Aziz Q, Bennett MI, Benoliel R, Cohen M, Evers S, Finnerup NB, First MB, Giamberardino MA, Kaasa S, Kosek E, Lavand’homme P, Nicholas M, Perrot S, Scholz J, Schug S, Smith BH, Svensson P, Vlaeyen JWS, Wang SJ. A classification of chronic pain for ICD-11. Pain. 2015 Jun;156(6):1003-1007.