Pain used to be considered a warning that you have suffered some tissue damage but, in a large percentage of people in pain, there is no correlation between pain and damage, even in highly controlled experiments.
There are several stories of pain-free major trauma; we discuss one in the blog ‘Pain: Is it All In My Head?’. The blog discusses an amateur Jockey, Phil, who came off his bicycle at great speed and fractured his skull, sternum, and spine, bruised his heart, spleen and other organs. Shortly after the accident, he stated:
“I thought I’d just got a cut to my head and pulled the muscles in my back. It was only really after the CT scan when they diagnosed me with the fractures that the pain and shock really kicked in.”
Some say pain is a warning that something is wrong. What about phantom limb pain? There cannot be something wrong with the limb because it is no longer there.
Experts define pain as ‘an unpleasant feeling in our body that makes us want to stop and change our behaviour’. Most modern definition involve both a physical and emotional component to pain. What we do know is pain is a complex and highly sophisticated protective mechanism.
How Does Pain Work? #
The body contains nociceptors that are specialised receptors which detect potentially dangerous alterations in temperature, chemical balance or pressure and send messages to the brain. These ‘danger’ receptors near your broken wrist, strained muscle or sprained ankle do not actually send pain to the brain because it is a sensation created by the brain, just like the ear drum detects air vibrations that are conveyed to the brain where it is turned into sound and thence into complex meanings like language, music or noise.
Pain is the output of the brain assessing information, including nociception data from the body, cognitive data such as expectations, previous experience, cultural and social norms and beliefs, and other sensory information like what you see, hear and otherwise perceive. Many other factors contribute to how we experience and express pain such as gender, age, education, socioeconomic status and whether the person in pain is speaking in their first language or not.
Pain Modulation #
The story of the cyclist, Phil, mentioned above, demonstrates that pain can be ‘turned off or down’. There are other stories of situations where pain is not produced in the body because the mind did not consider the stimuli significant. A gardener comes in from their yard and is surprised by a deep cut on her hand that they had not noticed whilst focused on their pruning. Or a soldier in a war is shot but feels little pain until they are safe in the barracks.
Research has shown the brain can tone down how intensely a harmful stimulus is experienced. This process is known as “pain modulation”. Conversely, pain can be ‘turned on/turned up by a stimulus that gives the brain credible evidence that the body is in danger and needs protecting such as stress and anxiety. In the case of the shot soldier, they are experiencing of Stress Induced Hypoalgesia (decreased pain). The brain has discounted the nociceptive information until they have escaped to a safe place.
In 2019, there was a very interesting article in the New York Times, “At 71, She’s Never Felt Pain or Anxiety. Now Scientists Know Why” that discussed the case of a woman who does not feel pain even when she damages herself. Researchers studied her and attribute her inability to feel pain to a microdeletion in part of a gene called FAAH-OUT that affects the endocannabinoid system. Equally as fascinating, is that this same person has never felt fear, depression or anxiety. This case study certainly indicates a link between what you feel when a bone is broken and what you feel when your heart is broken.
Does that mean it is all in your head? #
No, these nociceptors are spread around almost the whole body and act as the ‘eyes’ of the brain.
If there is a drastic change in the tissue environment – it heats up, the pH changes (e.g. lactic acid build up), is crushed, pinched, squeezed, or stretches too far – the nociceptors ring the alarm to help protect the tissues. They scream ‘DANGER!’, start inflammatory mechanisms that redirects blood flow and leads to the release of healing compounds from nearby tissues, therefore starting the repair process.
General or local anaesthetics “turn off” these nociceptors so they do not trigger these ‘danger’ messages, which means we can be pain-free despite major tissue trauma, such as when an insertion is made during an operation.
Danger Danger! #
Once the brain received the nociception it processes it, and if the brain concludes that that the situation is very dangerous, then the nociception becomes more sensitive. This is termed ‘descending facilitation’. If the brain decides the situation is nothing to worry about then the nociception becomes desensitised, called ‘descending inhibition’.
In persistent pain, or what used to be called ‘chronic pain’, the sensitivity of the various biological system involved in pain elevates so high that the relationship between the genuine danger and levels of pain becomes distorted. You become over-protected by pain.
That is why there is no easy fix for most persistent pain. The journey to recovery requires “patience, persistence, courage and good coaching” (Lorimer Moseley). The most effective interventions rely on progressively training the body and brain to be less protective.
Implications For Pain Control #
To decrease pain, you need to decrease information that suggests danger and increase information that suggests safety. Nociceptors can be switched off by analgesia, that is why if you are in severe pain it is important to use your medications, despite fears you may be ‘masking the pain’.
Alternatively, you can facilitate your brain and body’s danger-reduction continuums by engaging in anything that is correlated with safety. This can include being aware of how pain really works and the purpose it serves, exercise, mindfulness practices, coping strategies, talking to friends and family, and spending time in places you feel safe.
A mindfulness-based stress reduction (MBSR) program was developed in the late 1970s by Jon Kabat-Zinn at the University of Massachusetts Medical Center to complement medical treatment for cancer pain, chronic pain, stress, anxiety, depression, fibromyalgia, and other painful and psychological conditions. Kabat-Zinn described mindfulness as “the awareness that emerges through paying attention on purpose, in the present moment, and non-judgmentally to the unfolding of experience moment by moment.”
Mindfulness can be incorporated into daily activities like cooking, eating or cleaning. A literature review published in the Australian Journal of Primary Health reported on research into the effects of MBSR programs for people with chronic diseases including fibromyalgia, chronic pain, and rheumatoid arthritis. All the studies found the MBSR program to be a supportive therapy with positive effects.
Another very effective way to decrease pain levels is distraction therapy, where you direct the brain’s attention to something else. This has overlap with mindfulness in which you focus on a single point; let all your thought go and be in the present moment; and when you notice your thoughts have drifted from the present, gently bring your attention back to a single point of focus. Or you could just engage in an all-consuming activity with your family and friends to distract you.
If you are in pain, you should seek medical advice from a Specialist Physiotherapist, Osteopath or Consultant in Sport, Exercises & Musculoskeletal Medicine, to determine what is contributing to your pain and help in your recovery. Fill in the form below to book an appointment.