Acute vs. Chronic, Getting to Know Pain

Pain has a bad reputation, and for good reason. Who wants to hurt? However, at times it does serve an important function. You touch a hot pan – pain tells you to let go ASAP. Running on that recently sprained ankle – pain says give it a few more weeks. Of course, pain veers from purposeful to dreadful when it lingers for years. And long-term pain can be hugely debilitating and costly. If types of pain can be so divergent, it may be useful to ask what exactly is pain? It is defined as an unpleasant sensory experience that may be influenced by tissue damage, the condition of the nervous system, emotional state, and mental health. Simultaneously complicated and simple: pain is the experience of being in pain.

It’s important to understand that pain describes the experience rather than something specific happening at the painful site. It is something our brain perceives, not always something our body is trying to tell us. A common misconception is that all pain is the direct result of damage or injury. We define that type of pain as “acute pain.” Sensors in our body are triggered by temperature, chemicals, pressure, stretch, among other things. The sensors send this data to the brain via our nerves and spinal cord and the brain processes the input. If the stimulus is strong enough, we feel pain, a signal to back off what we’re currently doing. Acute pain is the helpful kind. It is short-lived, serves its purpose as a warning sign, and recedes when the stimulus is gone or the area has healed.

But how does pain occur without damage? After an injury, or with repetitive stress, changes can occur all along the pathway that leads to the brain. These deviations transform acute pain into chronic pain. The sensors described above can develop a lower threshold for stimulation. This means smaller inputs of temperature, pressure, etc. trigger the same painful outcome. The nerves and spinal cord can become irritable, amplifying the message sent to the brain. Importantly, profound changes can occur in the brain itself. The brain is malleable and changes in response to our experiences, it’s how we learn. With frequent unpleasant information coming in, the brain gets used to generating pain and creates a “pain pathway”. Over time and with frequent use, this pathway can become deeply ingrained. One could say the brain gets in the habit of feeling pain and has trouble breaking the cycle, generating it more frequently and strongly.

Acute pain usually presents a clear-cut issue to treat, while chronic pain is much more complicated. Fortunately, there are some effective ways to intervene. Treatments like massage and acupuncture can help alleviate symptoms. Physical therapy and mental health services can work to retrain the brain to break out of the pain pathway. Pain is rarely pleasant, but know there are ways to manage it. If you have questions about your symptoms make sure to reach out to your health care professional to explore options.

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About the Author:

A performer and bodyworker, I am delighted my unconventional path has led me to Physical Therapy. Through my work as a performance-based educator, I helped devise training on everything from environmental preservation to English literacy. The physical nature of the job eventually led me to train in massage and pilates which uncovered a desire to learn more about the body. Before I knew it I was back in school in the University of Minnesota’s DPT program. I look forward to uniting my background in writing, public speaking, and education with my passion for PT, in and beyond the clinical setting. Interested in connecting? You can find me on linkedin.   

References:
Dubin, Adrienne E., and Ardem Patapoutian. “Nociceptors: the sensors of the pain pathway.” The Journal of clinical investigation 120.11 (2010): 3760-3772.
Loeser, John D., and Rolf-Detlef Treede. “The Kyoto protocol of IASP basic pain Terminology.” Pain 137.3 (2008): 473-477.
Seifert, Frank, and Christian Maihöfner. “Functional and structural imaging of pain-induced neuroplasticity.” Current Opinion in Anesthesiology 24.5 (2011): 515-523.