Preprint The predictive role of pain catastrophising following genicular arterial embolisation for the treatment of mild and moderate knee OA, 2023, Harrison+

The predictive role of pain catastrophising following genicular arterial embolisation for the treatment of mild and moderate knee osteoarthritis
Richard Harrison; Tim Salomons; Sarah MacGill; Mark Little

Knee osteoarthritis (OA) is the most common form of OA and is not currently considered to be a curable disease. Specifically, mild-to-moderate knee OA that is resistant to conservative treatment, but does not warrant joint replacement, poses a significant clinical problem.

Genicular arterial embolisation (GAE) is an interventional radiological technique designed to subvert neoangiogenesis within the joint, in turn reducing pain and improving function. Preliminary data has identified a subset of patients who do not respond, despite a technically successful procedure. We therefore investigated individual differences in pain and pain perception to identify predictive pre-surgical markers for clinical outcomes. Specifically, we investigated pain catastrophising (PC) and its neural correlates using resting-state functional magnetic resonance imaging (rs-fMRI).

Thirty patients participated in a presurgical assessment battery during which they completed psychometric profiling and quantitative sensory testing. A subset of seventeen patients also completed an rs-fMRI session. Patients then recorded post-surgical outcomes at 6-weeks, 3-months, 12-months and 24-months. The dorsolateral prefrontal cortex (DLPFC) served as a seed for whole-brain voxel-wise connectivity with pain catastrophising scores entered as a regressor in group analysis. Pain catastrophising was associated with a myriad of aversive psychological/lifestyle variables at baseline, as well as a predisposition for attending to pain.

Surprisingly, high pain catastrophisers stood to gain the best improvements from GAE, with PC scores predicting the higher reductions in pain across all time-points. Seed-based whole-brain connectivity revealed that PCS was associated with higher connectivity between the DLPFC and areas of the brain associated with pain processing, suggesting more frequent engagement of top-down modulatory processes when experiencing pain.

These results are an early step towards understanding outcomes from novel interventional treatments for mild-to-moderate knee OA. Data suggests that improvements in pain and function via GAE could help high catastrophisers manage their pain, and in turn, the negative associations with pain that were identified at baseline.

Link | PDF (Preprint: MedRxiv)

 

Did they actually conclude that 'pain catastrophizing' reduced when the pain was reduced by a medical intervention? As some kind of revolutionary observation?

 

"Pain catastrophising"
"In severe pain".

The references where they question the construct are —

• Preoperative pain catastrophizing and postoperative pain after total knee arthroplasty: a prospective cohort study with one year follow-up (2016, BMC Musculoskeletal Disorders)
• Pain catastrophizing as a risk factor for chronic pain after total knee arthroplasty: a systematic review (2015, Journal of Pain Research)
• Is Pain Catastrophizing a Stable Trait or Dynamic State in Patients Scheduled for Knee Arthroplasty? (2012, The Clinical Journal of Pain)

 

Pain catastrophization is a nonsense concept. The scale they use is largely influenced by external factors, not how much someone worried about the pain. External factors would be:

• How bad the pain is
• How permanent the condition is
  
• How life-threatening the condition is
• How many treatments have been tried and failed

 

First author: Rich Harrison

CINN Pain Lab

"If you hold your hand close to a fire, the heat causes you to pull your hand away, to avoid the painful experience. This simplistic view of pain and our response to pain, as being a purely physical response and experience was thought to be an accurate representation. However, we now know that a great deal of pain can be purely psychological, and that people with chronic pain even after surgery and who present with no symptoms, can still feel pain which causes a great deal of discomfort and distress. Therefore, there is still a significant lack of knowledge with regards to understanding pain conceptually, and how best to manage it practically.

Reflecting this, the basis of the Pain Research Group at Reading is to take a two-pronged approach with understanding pain. Firstly, we implement novel research strategies to understand the theoretical and psychological basis of pain. This is achieved both by running practical lab-based experiments in the PainLab, as well as applying painful stimuli whilst participants are being scanned in the MR scanner, to understand the neural components. Secondly, we aim to translate our scientific knowledge practically, by consulting and implementing novel therapies and interventions, in order to treat patients suffering from pain-based illnesses. To do this, the Pain Research Group has strong clinical ties to the Royal Berkshire Hospital, and runs a number of clinical studies testing these solutions."

 

There should be human liberationists, ones with dreadlocks and army jackets and balaclavas and arts degrees and nose rings, breaking into Harrison’s Pain Lab and freeing the subjects from the MRI torture chambers, even if they are ill-equipped to survive in the sylvan outskirts of Reading.

I wouldn’t advise the activists to burn the lab down afterwards, of course, even though it might profoundly change Harrison’s attitudes to fire and pain, assuming he is a permanent voyeur on site.

 

Wut?

There seems to be a significant lack of knowledge with regards to understanding concepts, conceptually.

 

Indeed

 

I'd recommend just liberating him, and letting the people who understand pain stay on to run it.

 

"Pain catastrophising is described as a set of maladaptive cognitions characterised by heightened pain intensity and unpleasantness, as well as an inability to disengage from the experience of pain."

So basically they are saying that if pain is intense and deeply unpleasant people, not unsurprisingly, can find it a little tricky to disengage from it

Wow ground breaking really.

That's not 'catastrophising', that's a well formed automatic, protective, necessary, mechanism to keep people alive, to help them with information to keep themselves safe and well, and to take care of their basic needs for survival. To see it in any other way suggests a lack of knowledge of how we developed and thrive as a species.

 

"Pain catastrophising is often described as a robust, cognitive bias, representing a stable individual difference, although this position has been challenged more recently. It has been proposed that catastrophising may be a dynamic construct related to pain intensity."

How can this be stable trait when it'll vary with intensity and unpleasantness of pain sensations Cannot be separated....

Not unsurprisingly this has been challenged. By like.... people who can think

 

Am I understanding this:

People who are in more pain pre-intervention, then go on to gain more pain relief from pain releiving intervention.

Who knew?

 

No, it's an externally imposed judgment. As such it has no place in science.

 

So, people who have more pain report more pain, and likely express more pain?

What this is definitely worth a dozen Nobel prizes. The chocolate kind, but still.