A curious feature of chronic pain conditions is that people tend to have more than one. The term “chronic overlapping pain conditions” (COPCs) describes the co-occurrence of more than one of ten named conditions (1). Imagine a Venn-diagram type overlap of the symptoms of each condition.

The ten named conditions are not meant to be an exhaustive list but are conditions identified by the National Institutes of Health and the US Congress as exemplars of COPCs. The list has grown from an original six to ten conditions: temporomandibular disorder, fibromyalgia, irritable bowel syndrome, vulvodynia, myalgic encephalomyelitis/chronic fatigue syndrome, interstitial cystitis/painful bladder syndrome, endometriosis, chronic tension-type headache, migraine headache, and chronic lower back pain (1, 2).

Sometimes I feel like I’m participating in a Pokemon “collect ’em all” game with pains. Though I don’t know what I’m collecting, when I’ll next get a new one, or how many are left to come.

My own unfolding of my current constellation of pain symptoms/syndromes goes like this:

• 10 years old: temporomandibular joint (TMJ) disorder started; painful periods started
• 11 years old: chronic dislocating patella (knee cap) started
• 15 years old: carpal tunnel syndrome started
• 18 years old: more general, widespread pain started (subsequently diagnosed as fibromyalgia)

That list reduces years of pain and illness down to four bullet points. That is actually quite distressing to read. Seeing those bullet point feels like my experience is minimised. And I wrote it!

Some of these chronic pains started with an underlying structural cause. The TMJ disorder was likely caused by teeth crowding impacting on the space between the disc and ball of the TMJ joint. That lack of space was fixed with many years of dental work. Yet, I still experience residual pain.

The chronic dislocating patella was likely caused by an overly short tendon on the outside of my left leg preventing muscle forming on the opposite side. The tendon was therefore pulling the patella and there was no muscle to hold it. After several years of physiotherapy didn’t result in muscle build up, I had surgery to lengthen the tendon. More physiotherapy did result in muscle growth and the kneecap stopped dislocating. Yet, I still experience residual pain.

The carpal tunnel syndrome was likely caused by inflammation or a narrow gap putting pressure on nerves. After physiotherapy didn’t stop the progression of the pain or nerve damage, I had surgery to widen the space around the nerves in both hands. Yet I still experience residual pain.

The pain I link to my jaw, knee, and hands is different than it was pre-treatment. There was something going on, some on-going tissue damage, that was fixed by the interventions. The impairments in function that accompanied the pain were fixed by the interventions. I can open my mouth. My knee doesn’t dislocate. My hands don’t tingle and I can use them adequately. Yet a different kind of pain persisted and slowly spread throughout my body.

If we pause and think about what pain is, having more than one type of pain, or a more widespread pain, makes sense. Pain is linked to protection. It is an experience generated to prompt protection of body-tissue.

Thinking beyond the pain itself can also shine light on the broader protective processes. So far when I’ve written about pain here in Pinches, I’ve narrowed my description to focus on the pain. Theories of pain actually propose that while pain is the experience of perceived threat to body tissue, it is associated with many other protective physiological responses (3). Pain is just one output. Our motor, immune, sympathetic nervous, and hormonal systems are all recruited to protect us too (3).

Thinking about pain in this way can help to make sense of the association of chronic pain with other chronic conditions. Chronic pain, or pains, are also co-morbid (occur together) with other conditions; not only conditions with pain as the dominant feature. Those chronic overlapping pain conditions and co-morbidities are chronic protective processes in action (2, 3).

Over the last few years I’ve collected a series of non-pain symptoms and associated diagnoses which suggest that my body is functioning differently than it should (or how I would like it to):

• selective IGA deficiency (immune system; likely present since birth)
• hidradenitis suppurativa (autoinflammatory skin condition; present since my early 20s, recently progressed enough to be diagnosed)
• endometriosis (symptoms for years, waiting for a surgery to confirm diagnosis; associated with inflammation)

Of course, I’m speculating that my chronic pain and other chronic conditions are related to an overactive threat protection system. I’ll likely never know in my case for sure. However I can say that I’m not the only person to experience multiple chronic conditions. Having more than one chronic condition is part of day-to-day life for many people, not a rare exception (1).

In the next pinch, I’ll use my experience to illustrate some of the potential impacts of an overactive threat protection system on day-to-day life and on wider interactions with the mechanisms and systems of a big society.

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1. Maixner, W., Fillingim, R. B., Williams, D. A., Smith, S. B., & Slade, G. D. (2016). Overlapping chronic pain conditions: implications for diagnosis and classification. Journal of Pain, 17, T93 – T107. https://doi.org/10.1016/j.jpain.2016.06.002

2. Veasley C., Clare D., Clauw D. J., Cowley T., Nguyen R. H. N., Reinecke P., Vernon S. D., Williams D. A. (May, 2015). Impact of chronic overlapping pain conditions on public health and the urgent need for safe and effective treatment: 2015 analysis and policy recommendations [White Paper]. Chronic Pain Research Alliance. http://www.chronicpainresearch.org/public/CPRA_WhitePaper_2015-FINAL-Digital.pdf.

3. Moseley, G. L. (2007). Reconceptualising pain according to modern pain science. Physical Therapy Reviews, 12, 169–178. https://doi.org/10.1179/7108331907X223010