What is Chronic Pain?
Chronic pain is pain that lasts longer than normal tissue healing time (3-6 months) and affects an estimated 20% of people worldwide (1). Though the tissues have had time to heal sufficiently, the pain continues.
Chronic pain can greatly impact a person's life and has been associated with fear, anxiety, and depression (2,3,15). Therefore, it is important to both understand chronic pain and provide appropriate and effective treatment for it.
However, not all individuals with chronic pain have the same symptoms or presentations. In fact, pain itself is incredibly complex, and no two individuals will experience the same pain. But, within the chronic pain realm are two subcategories that can be used by the orthopedic manual physical therapist to ensure that each individual is cared for within the best general framework. These two broad categories are chronic recurrent pain and chronic persistent pain.
Chronic Recurrent Pain
Chronic recurrent pain is characterized by pain that is episodic – it may come and go, off and on, for years. The symptoms may be very similar during each episode, but the pain typically goes away or decreases considerably for periods of time in between. One example of a patient with chronic recurrent pain is one that reports doing too much activity when feeling good and then dealing with a severe flare-up afterward. One strategy to help these patients is pacing (4). Pacing refers to a responsible, calculated, and gradual increase in the amount or intensity of activity over a period of time to allow the tissues to adapt to the increasing demands.
Other patients in this category, however, may not be able to explain why symptoms keep returning and deny overdoing it with abrupt increases in activity levels. Sometimes, these persons have physical impairments or mechanical dysfunctions that contribute to the recurrences, and the orthopedic manual physical therapist should be able to identify these physical causes and treat them accordingly. For instance, patients with decreased hip abductor muscle endurance may experience lateral hip pain with increased activity or walking, which may lead to an abnormal gait and a subsequent increase in the strain on these tissues. The pain in this example may continue to come and go for several months or years, whenever the patient does too much walking, and may be successfully treated by an orthopedic manual physical therapist that is able to identify the musculoskeletal culprit.
Chronic recurrent pain is considered peripheral-dominant pain (5). "Peripheral-dominant" means that the origin of symptoms is nociception at the local tissue where the pain is perceived. Nociceptors are nerve cells that transmit sensory information – not pain – to the brain via the spinal cord for processing. Nociceptors do not perceive, produce, or transmit pain. Pain is experienced only after the sensation is sent to the brain, processed by the pain neuromatrix, and is determined to be a threat. It is the amazingly complex neural signature located in the brain that ultimately determines when a person experiences pain, and the body may or may not be involved in the process. Again, for the sensation to become painful, it must be perceived it as a threat. Unlike chronic recurrent pain, chronic persistent pain is not peripheral-dominant and has a much different presentation.
Chronic Persistent Pain
Chronic persistent pain is pain that has been present for more than 3-6 months and seems to be always present; no positions or movements seem to be able to relieve it. Tissues have had ample time heal but the patient continues to experience pain well beyond normal tissue healing times. These patients may have imaging findings in X-rays or MRIs that do not correlate with their symptoms (for example, their imaging may be relatively normal but they have severe pain). Therefore, their symptoms are not primarily from local or regional dysfunction in the tissues where the pain is perceived to be. Rather, it may be from a dysfunction in processing within the central nervous system, also known as central-dominant pain (6,7,8). Oftentimes these symptoms are reported to be unpredictable and widespread without consistent aggravating or easing factors (7,10). At times, these patients may present with exquisite tenderness to light touch and/or pain that is disproportionate to the extent of the injury (6,9).
Some patients with chronic persistent pain may feel as though their pain is ‘spreading’ to other areas of the body, or they report experiencing new pains distant from the original area of pain. This is due, in part, to the patient’s decreased ability to filter incoming signals. Since more signals are now sent indiscriminantly to the brain, more of them are then likely to be interpreted as pain by the processing centers (11).
Best Evidence-based Treatment for Chronic Pain
According to a 2022 systematic review which considered 118 trials and 9710 participants, most forms of exercise were beneficial for reducing chronic low back pain. They state: "Compared with control, all types of physical exercises were effective for improving pain... except for stretching exercises." (18)
However, treatment for patients with chronic persistent pain must be different than treatment provided for patients with chronic recurrent pain. Treatment for chronic recurrent pain with peripheral-dominant symptoms is likely to be most effective by addressing the specific neuromusculoskeletal and biomechanical deficits present while still incorporating pain science education to address any potential for a progression into chronic persistent pain.
Treatment for those with chronic persistent pain should include cognitive-based therapy, abundant pain science education, and a graded activity approach to exercise in order for patients with persistent pain to maximize their recovery (5,6,7,10,14,16). Orthopedic manual physical therapy may also be beneficial by systematically and responsibly progressing the intensity or volume of the techniques for a graded increase of input into the central nervous system. (17) There may also be benefit in collaboration with a mental health professional to address the psychological and emotional impact involved in the persistent pain and incorporate strategies to address these.
Successful orthopedic manual physical therapy for patients with chronic pain is dependent on proper classification by the skilled physical therapist and a discerning implementation of interventions that match each patient’s unique presentation within each of these broad classifications.
Dr. Damon Bescia is a fellowship-trained Doctor of Physical Therapy, board certified in orthopedics and sports physical therapy, who specializes in Orthopedic Manual Physical Therapy and serves Naperville and its surrounding communities by way of his Concierge Practice, providing private one-to-one orthopedic manual physical therapy for his clients. For more information, please visit https://www.napervillemanualphysicaltherapy.com.
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