Addressing Chronic Pain with Pain Neuroscience Education and Physical Therapy
Pain neuroscience describes pain as an output of the brain in which the nervous system functions as an alarm for the brain, signaling that there is damage in a certain part of the body. The brain interprets these signals to decide whether pain would be beneficial for healing, causing the nerves to increase their sensitivity in the injured area. In a patient with chronic pain, the nervous system remains hypervigilant, signaling to the brain that an area of the body is injured and painful, even when the tissue is no longer damaged. Physical therapists play a critical role in helping chronic pain patients manage their pain, improve their function and mobility, and enhance their overall quality of life. Combining physical therapy exercise and pain neuroscience education (PNE) helps chronic pain patients not only desensitize the sensitive chronic pain area through graded movement, but also help patients understand the mechanism of pain in their body.
Understanding the Science of Pain
Pain is a normal part of the human experience that is important for our survival, as pain signals to us that a certain area of the body is damaged. Pain is commonly understood as the result of tissue damage, which is the mechanism of pain during an acute phase of an injury, such as pulling a muscle in your back or twisting your ankle. However, the pain neuroscience model describes pain in terms of neurobiological and neurophysiological processes, offering a way to understand the mechanism of chronic pain that lasts for months or years.
Pain neuroscience describes pain as an output of the brain with the nervous system functioning as an alarm for the brain about pain in the body. When a body part is injured, the nerve endings in that area of the body are triggered and send warning signals to the brain. However, pain is not felt until the brain interprets the information from the nerves and decides whether the pain would be helpful to encourage protective behaviors to minimize further damage to the body part and allow for healing. This explains why initially an individual may suffer a significant injury but not experience the pain until later as the brain releases danger-blocking hormones to help the individual not experience pain to do what’s necessary to get out of danger and survive. Once the person is safe from the threat, the brain then communicates that pain ought to be felt so that steps are taken to protect and heal the damaged area.
The central nervous system can change its sensitivity level to pain and adjust the level of volume of pain signals, increasing sensitivity when pain is acute and that area of the body needs protection and decreasing the sensitivity when the area of the body heals. When you experience an injury, your nerves increase their sensitivity in the injured area to protect the body. During a normal recovery process of tissue damage, the nerves reduce their sensitivity as the tissue heals, signaling to the brain that the experience of pain in that area can decrease.
How Chronic Pain Develops
However, with chronic pain, the sensitivity of the nerves is turned up too loud for too long and the nerves become stuck in “sensitive mode.” This causes the brain to process this area as a threat and the nerves remain on high alert, such that the individual experiences pain in that area even when tissue damage has healed.
A neural process called long-term potentiation describes this process. The more times the brain uses a certain neural pathway (nerves signal pain for weeks), the easier it becomes to activate that pathway again and the less stimulus is required to trigger that pain. For chronic pain patients, the neural pathways that interpret pain remain continually activated, which causes the person to experience pain from that area without evident injury or in response to low stimuli, e.g. a mere touch to that area exhibits extreme pain.
The nervous system of the chronic pain patient becomes hypervigilant, known clinically as central sensitization. Central sensitization involves increased responsiveness, hypersensitivity, and hyper-communication of nerves to the brain due to normal or subthreshold stimuli, causing the brain to interpret that communication as chronic pain. Chronic pain affects 50 million American adults and is persistent pain that lasts three months or longer.
The following diagram illustrates the alarm system of the nervous system when injury occurs and the effect central sensitization has on the experience of pain and a chronic pain patient’s physical activity:
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Physical Therapy & Pain Neuroscience for Chronic Pain
Physical therapists can play a critical role in helping chronic pain patients manage their pain, improve their function and mobility, and enhance their overall quality of life. Combining physical therapy exercise and pain neuroscience education (PNE) helps chronic pain patients not only desensitize the sensitive chronic pain area through graded movement, but also helps patients understand the mechanism of pain in their body and reduce catastrophizing and fear-avoidant behaviors that have negatively impacted their quality of life.
Physical therapists utilize therapeutic, graded exercise to help chronic pain patients reduce their pain level by desensitizing the chronic pain area and improve their overall mobility and function. By carefully and gradually introducing exercise, the brain is trained to sense the problem pain area in the body without eliciting and increasing hyper-sensitive pain messaging. Through supervised and gradual movement, the patient can slowly build pain tolerance and desensitize the overactive central nervous system (CNS) that is perpetuating chronic pain.
The therapist may begin with gentle stretching to slowly improve range of motion in joints, reduce muscle tightness contributing to pain, increase circulation to muscles, and activate the parasympathetic nervous system. The patient may also start gentle aerobic and resistance movements in our warm water therapy pool. Water therapy not only decreases the amount of stress on your joints, but also exerts a gentle compressive force that reduces swelling and joint inflammation. Once the patient has gained confidence in movement, they can move on to aerobic movements like walking, the elliptical, or stationary cycling, and resistance training using bodyweight, resistance bands, and fixed or free weights.
Aerobic exercise can help reduce chronic pain by improving circulation, helping achieve a healthy weight, and moving synovial fluid through joints to increase range of motion and lessen pain. Resistance training can strengthen weak muscles and address muscles imbalances contributing to pain. Resistance training can also improve a person’s capacity to support bone and cartilage through improved musculature supporting movement around the joint, helping to relieve stiffness and pain in that area.
As the sensitivity of the CNS decreases with consistent therapeutic exercise and pain neuroscience education, the therapist may also use manual therapy to mobilize tight joints and soft tissues to increase range of motion, improve tissue quality, and reduce pain.
Research has shown that exercise and pain neuroscience education are effective in managing and reducing chronic pain. One study assessed 30 patients with chronic low back pain who underwent a core and gluteal strengthening program coupled with a lumbar flexibility program. Results showed that nearly all participants experienced significant improvement in low back pain regardless of how long the back pain had persisted prior to the intervention (patients had experienced low back pain anywhere from 3-12 months to more than 12 months).
Another study examined whether adding pain neuroscience education to therapeutic exercise would improve chronic neck pain patients’ pain disability index and pain catastrophizing. In the study, 24 chronic neck pain patients underwent a therapeutic exercise intervention, 24 combined exercise and PNE, and 24 were a control group who received brochures on proper posture. Researchers found that therapeutic exercise combined with pain neuroscience education reduced the pain-disability index, pain catastrophizing, and fear-avoidance beliefs more than therapeutic exercise along in patients with chronic neck pain.
Another study assessed patients with chronic spinal pain who underwent PNE and therapeutic group exercise and found that these patients experienced improved quality of life, less catastrophizing or central sensitization, decreased pain intensity, and decreased pressure pain thresholds. These improvements post-intervention was maintained at a six-months follow up.
Pain neuroscience education offers patients a deeper understanding of the mechanism of pain in the body and our body’s processing of pain. Physical therapy combined with pain neuroscience education provides patients an active role in their recovery and pain management and helps to reduce pain and restore patients to the highest possible level of activity, function, and quality of life. Start working with a physical therapist today!
