Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. It serves as a protective mechanism, alerting the body to harmful stimuli. Pain can be acute, arising suddenly in response to injury or illness, or chronic, persisting beyond the usual healing course. It encompasses both physical sensations and the emotional responses to those sensations.
Introduction to pain perception
As defined by the International Association for the Study of Pain (IASP), pain is an “unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage” (Raja et al., 2020).
How, then, can physical damage induce pain? To respond to this question, we must introduce a complex body system called the central nervous system (CNS). The brain and the spinal cord mainly make the CNS. Along the CNS, information is transmitted, like electrical impulses. Along those impulses, we have nociceptive signals, which are signals carried by nociceptive neurons (from Latin nocere ‘to harm or hurt’; lit. ‘pain receptor’). The role of these neurons is to let the CNS know when potential damage does happen.
So, when you sting your hand with the thorn of a rose, image a little guy, running from your finger to the brain, screaming, “Damage, Damage!” and next, image another little guy, running down from the CNS to the finger screaming “Pain, Pain!”.
This is an easy way to simplify the pain response.
Pain Processing phases
Understanding pain involves recognizing its three key phases: transduction, transmission, and modulation. Transduction is the initial stage where painful stimuli, such as a cut or burn, are converted into electrical signals by sensory receptors in the body. These signals then travel through transmission, moving along nerve fibres to the spinal cord and brain. Once in the brain, pain undergoes modulation, a complex process where the intensity and perception of the pain signal are altered. This phase involves several key brain regions, including the thalamus, which relays pain signals to other parts of the brain; the somatosensory cortex, which helps identify the location and intensity of the pain; and the limbic system, including the amygdala and hippocampus, which contribute to the emotional and psychological aspects of pain. The prefrontal cortex also plays a role in cognitive evaluation and decision-making regarding pain. Modulation can involve both descending pathways from the brain that can inhibit or amplify pain signals, influenced by factors such as stress, mood, and past experiences. Understanding these processes helps in developing targeted pain management strategies that aim to interrupt or adjust pain signals at different stages.
Inflammatory response.
Once physical damage does occur, a pain response is created, and to start a healing process, the CNS system, in collaboration with another body system, puts in place what we know as Inflammatory Response (IR). The IR is an automatic body response to damage, where the CNS starts caring for the body. To do so, the CNS would send extra blood flow to the area, it would constrict the blood vessels in the area, and sensitize the area, which means it would make that area more sensitive to stimulus, and this is because it wants to tell the body to be careful on not doing further damage. That said, the inflammatory response would last 24 to 72 hours post-injury. After this time frame, the inflammatory response should wind down. Indeed, during this time frame, taking any anti-inflammatories or using an ice pack is not recommended because the first would stop the inflammatory response, and the second would slow down the blood flow to the area.
Tissue Healing time
Any tissue in the body can and would heal on its own, regardless of the care you put in place. When we say any tissue, we refer to musculoskeletal tissues, which include bone, muscle, tendon, ligaments nerves and skin. Actually, there can be an exception for nerve and skin regeneration, which is based on the entity of the damage.
So, the difference between the different tissue healing processes is time. Indeed, a muscle, based on the type of tear, of course, would have a different healing time than a bone fracture, and no external stimulus can boost the healing time process. However, external stimuli can help improve the quality of the healing process. We already discussed this in the exercises blog post.
Chronic Pain and possible cure from it
So chronic pain, as we already defined, is a pain that lasts longer than three months, and it can linger around even when there is no tissue damage left. This is possible when the nociceptors are more sensitive to stimulus. Different is the type of sensitization that the nociception can reach, and therefore, it is fair now to introduce concepts like allodynia, which is defined as “pain due to a stimulus that does not normally provoke pain” and hyperalgesia that is defined as increased pain from a stimulus that usually provokes pain.
When this hypersensitisation is achieved, it’s hard to believe that things can change, especially when, after months of pain, several practitioners did try to help you and the only thing that is realising the pain is heavy meds.
Recent studies
In a more recent study by Ashar et al. (2021), they obtained some significant results with Pain Reprocessing Therapy (PRT), which did show substantial promise for chronic back pain (CBP) relief through a randomized clinical trial involving 151 participants. This study compared PRT with open-label placebo and usual care, using a combination of telehealth and in-person sessions to shift patients’ beliefs about their pain from being injury-based to brain-generated. Remarkably, 66% of those undergoing PRT were pain-free or nearly pain-free post-treatment, a significant improvement over 20% in the placebo group and 10% in the usual care group. This relief was largely sustained over a year. fMRI scans indicated that PRT altered brain activity, increasing connectivity between the prefrontal cortex and sensory areas while reducing pain-related responses. Additionally, PRT led to improvements in disability, anger, sleep, and depression. The changes in pain beliefs were identified as key in mediating the therapy’s effects, highlighting PRT’s potential as an effective psychological treatment for chronic pain.
How Melbourne Massage and Treatment can help?
At Melbourne Massage and Treatment, I do dedicate myself to helping anyone who is in pain, and with my extended Myotherapy training, I have tools that can help those who are suffering from Acute and Chronic Pain.
First, already understanding that the patient is suffering from pain and that they are not making it up is a giant step forward in creating trust between myself and the patient. Sharing the knowledge above can help the patient feel secure that they are believed and trusted about their presentation. Lastly, but not least importantly, techniques like myotherapy, manual lymphatic drainage (MLD), dry needling, and exercise prescription are valid tools to manage and potentially invert a chronic pain presentation.
On the other hand, Melbourne Massage and Treatment has moved to a new locations in July 2024 and is now part of a team of health professionals that includes psychologists like Dr Mohsen Dehghani, who specialises in working with chronic pain patients.
In conclusion, if you need treatment because of chronic pain, do not hesitate to book now your next Myotherapy or MLD appointment.
FAQ
Q: What is chronic pain and how is it different from acute pain?
A: Chronic pain is defined as pain lasting longer than three months, persisting even after the initial tissue damage has healed. Unlike acute pain, which is a direct response to injury and resolves with healing, chronic pain can linger and may be due to ongoing issues with nociceptive sensitivity.
Q: What is the role of the central nervous system (CNS) in pain perception?
A: The CNS, consisting of the brain and spinal cord, processes nociceptive signals—electrical impulses sent by pain receptors. These signals alert the CNS to potential or actual tissue damage, resulting in the experience of pain.
Q: What is the inflammatory response and how does it affect healing?
A: The inflammatory response is the body’s automatic reaction to tissue damage, involving increased blood flow and heightened sensitivity in the affected area to prevent further injury. This response typically lasts 24 to 72 hours, after which it should subside to allow for healing.
Q: How long does it take for different tissues to heal?
A: Healing times vary by tissue type. Musculoskeletal tissues like muscles and bones have different recovery times, and while healing processes are intrinsic, external factors like proper care can enhance the quality of healing.
Q: What are allodynia and hyperalgesia?
A: Allodynia is pain caused by stimuli that typically do not provoke pain, while hyperalgesia refers to heightened pain responses to stimuli that usually cause pain. Both conditions can be part of chronic pain syndromes where nociceptors become overly sensitive.
Q: How can Pain Reprocessing Therapy (PRT) help with chronic pain?
A: Pain Reprocessing Therapy (PRT) has shown promise in treating chronic pain by altering patients’ beliefs about their pain from being injury-based to brain-generated. Studies indicate significant improvements in pain relief, disability, and related symptoms, with sustained benefits over time.