Part II: The Stress-Pain Cycle

Pain is one of the biggest driving forces that causes patients to seek physical therapy intervention. Whether it is from a traumatic injury, overuse, degeneration, post-surgery, or other factors, the vast majority of cases our physical therapists treat is musculoskeletal pain.

Understanding Pain

The International Association for the Study of Pain defines pain as “an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage.” Several key factors that further define is that 1) pain is personal experience; 2) pain is different than just the activation of our sensory neurons, or nociception; 3) we learn the concept of pain through human development; 4) an individual’s pain should be respected; 5) verbal expression of pain is not the only indication that it exists; 6) pain can be harmful to one’s well-being, despite that it is also adaptive.

Acute Pain

Our sensory systems protect our bodies and help to identify, locate, and recognize tissue damage via the perception of pain. This concept explains acute pain, where an alarming signal is sent from damaged tissues in the body and transmitted through specific neurologic pathways to the brain. When we feel acute pain, it provides clues as to what disease or injury is occurring, which leads to a treatment to alleviate the source of pain.

Chronic Pain

More recently, pain has been viewed as a multi-dimensional entity that includes sensory, cognitive, and emotional aspects. This is certainly true of chronic pain. The simple definition of chronic pain is that it is pain that has persisted for more than three months. Both cognitive and emotional qualities can affect our perception of pain and how it is processed in our brains. Studies have shown that our brains’ pain pathways are altered by our attentional state, positive or negative emotions, and other factors that are directly unrelated to the pain itself.

Long-term Affects

Interestingly, studies have also found that prolonged pain experiences can lead to structural changes in the brain. This sort of plasticity, which describes changes to our nervous system, can become maladaptive in certain cases of chronic pain, and pain no longer is a guardian of our bodies’ health, but instead can turn into a disease itself. Studies of chronic low back pain, fibromyalgia, irritable bowel syndrome, and chronic headache pain found decreased gray matter in certain areas within the brain.

In turn, it is certainly concerning to consider how this affects the rest of our functional, bodily systems. These diminutive changes to our brain tissues have detrimental interactions on our sensory, immune, and cognitive processes. These abnormal changes likely also describe how an acute pain can become chronic; that is, a temporary pain that changes into a permanent problem.

It is clear that dealing with a chronic pain state is physically and cognitively stressful, and could easily turn into a self-perpetuating cycle! Knowing how to recognize and manage our pains is of the utmost importance, especially since most of us are juggling much more in life than just trying to take care of our bodies! If we are privileged enough to be able to impart some control and management over our pains and stresses, we must try.

…Coming Up

The next blog post in the Stress & Pain series will discuss effective, evidence-based methods for management of stress and pain.

IASP. IASP announces revised definition of pain. July 16, 2020.

Crofford LJ. Chronic pain: where the body meets the brain. Transactions of the American Clinical and Climatological Association. 2015. 126: 167-179.

Kumar KH. Elavarasi P. Definition of pain and classification of pain disorders. Journal of Advanced Clinical & Research Insights. 2016. 3: 87-90.

May A. Chronic pain may change the structure of the brain. International Association for the Study of Pain. 2008. 137: 7-15.