Persistent Pain: An Independent Disease State?

I recently began reading C.S. Lewis' The Problem of Pain. As with many of Lewis' writings, it is remarkable in both it's depth and simplicity. So many questions arise when it comes to the issue of pain, particularly for this therapist. Because I don't like weak links, I figured I'd better start looking for answers!

One aspect of a good question is that it often gives rise to more even better and more clinically relevant questions. Many physical therapists (myself included) emerge from entry-level training with a rather unsophisticated understanding of pain. We are more apt to enter the workforce with a strong understanding of pathoanatomy and biomechanics as it pertains to movement. If our goal is for our profession to evolve into becoming entry-level providers, we should have no tolerance for blind spots.

In the coming weeks, I will be incorporating the rather complex subject of pain as it pertains to common orthopedic conditions we encounter. More importantly, I will place emphasis on relevance to both assessment and treatment. I hope you will get as much out of the articles as I have in researching them. Mercifully, the topics will appease those of you with an appetite for physiology versus psychology.

Today's article comes from the Journal of Pain and Symptom Management on the issue of persistent pain and is truly an eye-opening read. Based on our study of pathophysiology, the concept of persistent or chronic pain doesn't always connect with our understanding of the inflammatory process. While there is clearly an inflammatory component to the acute pain our patients' experience, the relationship between tissue damage and persistent pain becomes much less clear in more.

The review provides evidence for "independent, pain-perpetuating pathophysiologic changes that occur after, or in the absence of, acute painful conditions or concomitant painful conditions." The review's author, anesthesiologist Michael Cousins, makes a very strong argument for persistent pain as a distinct pathological entity warranting specific attention from diagnosis through management. Cousins' contention is that failure to acknowledge the distinct physiology of persistent pain is likely to result in suboptimal care.

Contrary to much of the cognitive-behavioral pain literature I've tried to choke down over the years, this article provides the reader with some pretty significant pathophysiology supporting the concept of persistent pain as a distinct entity. I was particularly impressed with the physiology of peripheral sensitization, spinal cord events, and central nervous system changes that result from persistent pain. There is a relatively brief discussion of psychologic and environmental contributors,but the weight of the article is devoted to the biologic processes behind persistent pain.

Pain is not something orthopedic therapists may find particularly interesting or even relevant to their daily practice. The "no pain no gain" philosophy does have its time and place. However, what if there is a better way? I have no illusions of becoming the next pain-guru nor will I turn this into another freaky pain-blog, but I think we can take our practice to the next level by improving our understanding of pain in an orthopedic setting.


COUSINS, M. (2007). Persistent Pain: A Disease Entity. Journal of Pain and Symptom Management, 33(2), S4-S10. DOI: 10.1016/j.jpainsymman.2006.09.007