Complex regional pain syndrome – Autoimmune or functional neurologic syndrome, Chang et al, 2021

[Andy]

Complex regional pain syndrome (CRPS) purports to explain extremity pain accompanied by a variety of subjective complaints, including sensitivity to touch, fatigue, burning sensations, allodynia and signs consistent with voluntary immobilization, including skin changes, edema and trophic changes. By its own definition, CRPS pain is disproportionate to any inciting event or underlying pathology, which means that the syndrome describes non-anatomic and exaggerated symptoms. Although CRPS was coined in the early 1990s, physicians have described unexplained exaggerated pain for centuries. Before a small group of researchers assigned this historical phenomenon with the name CRPS, other physicians in various subspecialties investigated the existence of a common pathophysiologic mechanism but found none.

The literature was searched for evidence of a reproducible pathologic mechanism for CRPS. Although some have suggested that CRPS is an autoimmune disease, there is a paucity of evidence to support this. While cytokines such as IL-1β, IL-6 and TNF-α have been detected during the early phases of CRPS, this cannot lead to the conclusion that CRPS is an autoimmune disease, nor that it is an autoinflammatory disorder. Moreover, intravenous immunoglobulin has showed inconsistent results in the treatment of CRPS. On the other hand, CRPS has been found to meet at least three out of four criteria of malingering, which was previously a DSM-IV diagnosis; and its diagnostic criteria are virtually identical to current DSM-5 Functional Neurological Disorder (“FND”), and proposed ICD-11 classification, which includes FND as a distinct neurological diagnosis apart from any psychiatric condition.

Unfortunately, the creation of CPRS is not merely misguided brand marketing. It has serious social and health issues. At least in part, the existence of CRPS has led to the labeling of many patients with a diagnosis that allows the inappropriate use of invasive surgery, addictive opioids, and ketamine. The CRPS hypothesis also ignores the nature and purpose of pain, as a symptom of some organic or psychological process.

Physicians have long encountered patients who voice symptoms that cannot be biologically explained. Terminology historically used to describe this phenomenon have been medically unexplained symptoms (“MUS”), hysterical, somatic, non-organic, psychogenic, conversion disorder, or dissociative symptoms. The more recent trend describes disorders where there is a functional, rather than structural cause of the symptoms, as “functional disorders.” Physicians report high success treating functional neurological symptoms with reassurance, physiotherapy, and cognitive behavior therapy measured in terms of functional improvement.

The CRPS label, however, neither leads to functional improvement in these patients nor resolution of symptoms. Under principles of evidence-based medicine, the CRPS label should be abandoned and the syndrome should simply be considered a subset of FNDs, specifically Functional Pain Disorder; and treated appropriately.

Open access, https://www.sciencedirect.com/science/article/pii/S2589909020300472

 

[shak8]

Put in the wastebasket bin and then "treated appropriately". Hmm.

 

[wigglethemouse]

How awful. This reads like a hit job. Why would a lawyer be an author.

Christopher Chang ab, Patrick McDonnell c, M. Eric Gershwin a

a Division of Rheumatology, Allergy and Clinical Immunology, University of California, Davis, 451 Health Sciences Drive, Suite 6510, Davis, CA, 95616, USA

b Division of Immunology, Allergy and Rheumatology, Joe DiMaggio Children’s Hospital and Memorial Healthcare System, 1131 N 35th Avenue, Suite 220, Hollywood, FL, 33021, USA

c Law Offices of McDonnell & Associates, King of Prussia, PA, USA

I'm speculating here but this smells like insurance industry behind this. Many workplace long term disability policies do not cover FND. Perhaps this is part of building a scientific paper portfolio to be used as evidence in court...

 

[rvallee]

The CRPS label, however, neither leads to functional improvement in these patients nor resolution of symptoms

Well, duh. Who would even think such an absurd thing? It's not some evil spirit where if you know their name they can't hurt you. What is this nonsense? Why is medical research so excessively incompetent?

Patient: is sick with cancer

Doctor: you have cancer

Patient: wow the disease is completely gone because you named it thank you strong smart doctor

Seriously what is this nonsense?

 

[Joan Crawford]

Open access, https://www.sciencedirect.com/science/article/pii/S2589909020300472

Wow, just wow. What a hateful article. The mind boggles. Totally bizarre.

 

[Joan Crawford]

Open access, https://www.sciencedirect.com/science/article/pii/S2589909020300472

"and signs consistent with voluntary immobilization, including skin changes, edema and trophic changes." Really? Voluntary? Taking the piss

 

[Sean]

Physicians report high success treating functional neurological symptoms with reassurance, physiotherapy, and cognitive behavior therapy measured in terms of functional improvement.

"Physicians report"

What a bunch of utter crap. Rigorous trials, or GTF out of the game.

Otherwise 'patients report physicians useless abusive fraudulent arseholes' is equally valid.

Sure you want to go down that path?

 

[Sean]

I'm speculating here but this smells like insurance industry behind this. Many workplace long term disability policies do not cover FND. Perhaps this is part of building a scientific paper portfolio to be used as evidence in court...

Yep. Sure has that stench about it.

 

[Sid]

Sickening stuff.

 

[Mithriel]

A friend has something that could be called this. He fell down a flight of stairs about 10 years ago, banging his shoulder against a wall on the way down. Since then he gets painful episodes now and again.

His shoulder gets very painful his hands swell to twice their normal size and turn blue. he only thing that helps is immobilisation, paracetamol and time. He gains nothing from these episodes as another disease prevents him working and he already on benefits.

How someone can be malingering by making their hand swell and turn blue is beyond me, as is how psychological distress could do it either.

Not long ago, Jon Stone published a paper on CRPS which concluded

" FND is no longer assumed to be only the result of ‘conversion’ of psychological conflict but is understood as a complex interplay between physiological stimulus, expectation, learning and attention mediated through a Bayesian framework, with biopsychosocial predisposing, triggering and perpetuating inputs. Building on this new ‘whole brain’ perspective of FND, we reframe the debate about the ‘psychological versus physical’ basis of CRPS. We recognise how CRPS research may inform mechanistic understanding of FND and conversely, how advances in FND, especially treatment, have implications for improving understanding and management of CRPS."