Pain Neuroscience and Physical Therapy

Pain neuroscience education offers patients a deeper understanding of the mechanism of pain in the body and our body’s processing of pain. Pain is a survival mechanism to protect an area of the body that the brain perceives as damaged. 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.

What is pain and pain science?

Pain is a normal part of the human experience. It is a survival mechanism whose purpose is to protect an area of the body that the brain perceives as damaged. There are two common understandings of pain: 1) the anatomical model of pain wherein pain is caused by tissue damage, which is the mechanism of pain during an acute phase of an injury where damage to the body leads to immediate pain, and 2) the pain science model which explains pain in terms of neurobiological and neurophysiological processes.

In pain neuroscience, pain is understood as an output of the brain, meaning the experience of pain is created by the brain. When a body part is damaged, the nerve endings in that area of the body are triggered and send warning signals to the brain. Pain, however, is not felt until the brain interprets the information from the nerves and decides whether pain would be helpful to encourage protective behaviors to minimize further damage to that body part and allow for healing.  

For example, you may have a bruise on your body, thus tissue damage, from bumping into a table, but you do not experience pain because your brain does not perceive the bruise as a threat. On the other extreme, a surfer who has had their arm bit off by a shark does not feel pain initially because experiencing pain at that moment would prevent the surfer from engaging in actions that would allow him to survive, like swimming away. The brain releases danger-blocking hormones to help the surfer not experience pain to do what’s necessary to get out of danger; once the surfer is safe, then the brain will communicate that pain ought to be felt in the injured arm to ensure steps are taking to heal the damaged area.

Pain essentially functions as the body’s alarm system with the nervous system acting as the alarm. When the alarm goes off from the nerves in the injured area, the brain sends a signal for pain in the body and the nerves in that area increase their sensitivity to protect you. Once the injury heals, pain decreases as the nerves reduce their sensitivity.

Chronic Pain & Pain Neuroscience

Chronic pain is defined as pain that lasts more than three months. It can become progressively worse and reoccur intermittently, outlasting the normal healing process. Pain is communicated through the central nervous system: the network of nerves throughout your body and your brain’s interpretation of their messaging. 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 that area of the body heals.

However, in chronic pain, the sensitivity of the nerves is turned up too loud for too long and it does not calm down, leaving the patient with an extra sensitive pain alarm system. With chronic pain, nerves can get stuck in the sensitive mode causing the brain to continue to perceive that area as a potential threat and therefore painful, even if there is no longer any tissue damage.  

Pain physiology predicates that the longer pain goes on, the easier it becomes to feel that pain, which is due to the neural process, “long-term potentiation.” This means that the more times the brain uses a certain neural pathway, 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 interpreting pain remain continually activated causing the individual to continue to experience pain from that area even without evident injury or low stimuli (a mere touch to that area can exhibit extreme pain).

Chronic pain patients therefore often have increased hypervigilance of the central nervous system, described clinically as central sensitization. Central sensitization is increased responsiveness, hypersensitivity, and hyper-communication of nerves to the brain due to normal and subthreshold stimuli, causing the brain to interpret that communication as chronic pain.

What role does pain science play in physical therapy? 

Physical therapists can use pain neuroscience as an education tool to explain the process of pain and the experience of pain in the body to patients, particularly chronic pain patients, to improve function and quality of life and gently and gradually decrease the patient’s sensitivity to stimuli that induce pain. A 2011 systemic review noted that for musculoskeletal pain, pain neuroscience education provided evidence of reductions in pain, disability, and pain catastrophizing and improvements in physical movement in patients.

Physical therapists work with patients, particularly chronic pain patients, to reduce their pain level and restore them to the highest possible level of activity and function. Therapeutic, graded exercise is used to allow the patient to gradually increase their aerobic ability, improve coordination, reduce stress and strain on the body, and decrease pain. 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 is able to slowly build pain tolerance and desensitize the overactive central nervous system (CNS) that is perpetuating their chronic pain. 

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. Dry needling is also used to decrease pain by deactivating trigger points, hyper-irritable taut bands of muscle that contribute to chronic pain by producing referred pain.

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.