In 1989, the contemporary version of Batman was Michael Keeton, and his nemesis Joker was played by Jack Nicholson. The movie provides a smorgasbord of wonderful quotes, but two stick out in my mind. The Joker notes "I have given a name to my pain, and it is Batman!" The Joker also provides some medical advice: "haven't you ever heard of the healing power of laughter?" Is there some palliation or remediation in having a name for our pain? Is the patient's perception of symptoms and anatomical dysfunction impacted by attitude and overall situation?
Over a couple of years in this workers' compensation community, I have met a fair number of injured workers, employers, doctors, lawyers, and more. There is persistence in the occurrence of injury, and the struggles with care and treatment. We are pleased that frequency continues to decrease, but injury persists. There are hurdles to clear, examinations to endure, and testing to perform. Certainly, there are some injuries in which causation and treatment are more obvious. After all, a broken bone is a broken bone, and the x-ray pretty certainly demonstrates that.
However, causation and treatment questions can be more vexing in other circumstances, and those are the ones that tend to defy self-execution and venture into the dispute process. Many of these involve complaints and symptoms that are not perceived by medical professionals as typical or expected. One in particular, "pain," is common and persistent. The opioid crisis that has killed so many illustrates the pervasiveness of pain and our marked difficulty in mediating or eliminating pain.
I was surprised in a recent meeting to learn of a "third kind" of pain that is being discussed by medical professionals, perhaps mostly pain specialists. There is seemingly general recognition of two types of pain:
"nociceptive pain, which is caused by ongoing inflammation and damage of tissues, and neuropathic pain, which is caused by nerve damage."
With either, there are likely to be physical abnormalities that can be observed by the clinician through either visual perception (inflammation) or various testing (electrodiagnostic for nerve function assessment). In short, there is a physically discernable physical damage source to which perceptions of pain may be traced. With that source identified, treatment can be directed to reducing that inflammation or repairing that damage.
But what of those instances in which pain is described, and yet no such inflammation, tissue damage, or nerve damage is discerned? Then, perhaps, there is a pain for which there is no name. And, the vagueness or uncertainty of that is challenging. Is there a benefit in being able to point to that pain with a label or name? I like "Batman," but that is admittedly taken already.
Often, physicians testify that there are pain complaints, but without objective signs of injury or tissue damage. I have seen this referred to as "inexplicable" pain, or "atypical" pain, or "unspecified" pain, or pain of "unknown etiology." There are likely many other ways to label such complaints. Some are merely descriptive, and others may tend to the pejorative. There are serious challenges with compensability and treatment in workers' compensation when there is such ambiguity. There is admittedly some comfort to us when a source of pain is identified, described, and can be treated. Sun Tzu is often quoted regarding the value of "knowing your enemy," and treatment is similarly facilitated when the target is known.
The recent mention of the "third kind of pain" intrigued me. A Google search or two later, I landed on an article in the Lancet: Nociplastic pain: towards an understanding of prevalent pain conditions." This article explained there are two accepted types of pain, mentioned above, "nociceptive" and "neuropathic." Additionally, an "international community of pain researchers" has purportedly coined the title "Nociplastic pain." This is described as a "semantic term" to describe or label "a third category of pain that is mechanistically distinct."
The authors of this article contend that this "third type" of pain may independently cause complaints. Alternatively, it may be perceived by a patient in conjunction with either neuropathic or nociceptive pain in "conditions such as fibromyalgia or tension-type headache." They assert that this pain may play a contributing role to overall symptoms independently or in some "mixed-pain state" associated with a variety of injuries or illnesses.
Though this makes the pain sound somewhat non-descript and vague, the authors contend that not only can it be treated, but that it will be best treated with "different therapies than nociceptive pain." That is intriguing. This is a pain that these scientists believe is different in that the cause is not discernable tissue damage or inflammation and which can be treated, but uniquely. If one cannot treat the source, e.g. tissue damage, how is the treatment directed?
There is also the suggestion that this pain is not as responsive to modalities "such as anti-inflammatory drugs and opioids, surgery, or injections." It is therefore perhaps possible that misdirected opioids during that challenging period were unsuccessful or minimally affective through toleration, resistance, or because they were being directed at a pain that is naturally unresponsive to such palliation?
There is much interest in pain. Pain is important in the realm of workers' compensation as it is a medical phenomenon (something requiring treatment). However, it is as important as a disability or impairment construct. According to Nociplastic Pain Criteria or Recognition of Central Sensitization? Pain Phenotyping in the Past, Present and Future," the prevalence of pain is significant. The authors of this second article note that "Chronic pain is the most prevalent disease worldwide, leading to substantial disability and enormous socioeconomic burden."
Some would lean toward heart disease as the most prevalent disease. See Life Expectancy and Risk (September 2022). Google "most prevalent disease worldwide" and your results will lead with heart disease on the World Health Organization website. But, that is admittedly focused on "fatal" disease. The first search hit that is not seemingly focused on fatality is Our World in Data, and it is similarly not focused on pain in its "burden of disease." Thus, the "most prevalent" assertion may require significant reading to substantiate.
But, the authors of Nociplastic Pain Criteria contend that pain is
- "responsible for the highest number of years lived with disability"
- "the most expensive cause of work-related disability"
- "a non-communicable disease with a large impact on public health."
Perhaps the disparity is that pain could be less likely to be fatal? Despite these characterizations supporting the seriousness of pain, the authors similarly concede that it "is often non-specific." There is at least the implication that "there is no pathology or tissue damage" to explain some complaints. Alternatively, "that the limited amount of pathology or tissue damage is not severe enough to explain the pain experience." We have been told that there is science to support that different people experience pain differently. See Individual Differences in Pain (PMC 2017). Perhaps our individuality impacts the "pain experience?"
It is notable that the authors of Nociplastic Pain Criteria focus on the "pain experience," and as such avoid a more skeptical or dubious pain "description" or "complaint." There is seemingly an inherent trust or faith in the pain that is described. One might perceive there some endorsement of the symptoms perceived, and the accuracy of the complaint.
One wonders if having a name for one's pain is of benefit. Does labeling it "Batman" or "Nociplastic" render it somehow more understandable or comprehensible? Certainly, there is at least some benefit in consistent labeling, and "Nociplastic" perhaps seems an improvement over "unknown etiology" or similar. Almost a century ago, Marcus Haase published Etiology Unknown in the Journal of the American Medical Association (JAMA, 1923). In it, he observed:
"I doubt seriously whether there is a more humiliating moment in the life of a medical man, either as teacher or practitioner, than when asked by a student or patient, 'What is the cause of this?' and he is forced to say, 'I do not know.'"
Thus, there is perhaps salve in having a name? Do we feel better, responding to the question of "what is the cause of this" if we have a label? "Why, you see, this is Nociplastic pain." Thus, an answer to the question, but merely a label nonetheless.
But, is there science to support that pain is in fact present and disabling when there is no associated demonstrative physical damage, neurological damage, or pathology as is expected in nociceptive and neuropathic pain? Is there objectivity to underlie support for this third label, and the existence of actual pain in a particular patient? Is the challenge in people being unique and different in their perceptions and even expressions of pain?
More importantly, perhaps, is the question of how can such "Nociplastic" pain be verified and quantified? How might it be treated and ameliorated with the ultimate goal of diminishing the debilitating impact or perception of pain as expressed by the authors of Nociplastic Pain Criteria? As science continues its struggle with so many mysteries of the human condition, perhaps progress will come as regards our understanding of both etiology and treatment of this pain perception. In that regard, perhaps naming our pain is a reasonable first step?
