Why is it that some people recover from an injury and others take longer than expected or continue to have problems beyond a normal healing time? It’s the latter group that I spend a great deal of time with, helping them to develop understanding of their pain and devising a plan of what they must do to move forward.
The science of pain has moved on rapidly over the past 5 years with the neuroimmune system revealing some very interesting mechanisms that are fundamental to the pain experience. Groups of researchers around the World are gradually putting together the pieces of one of the most complex puzzles, that of pain, in tandem with modern thinkers who are blending science with philosophy to craft better ways of approaching the problem. This incorporates closing the gap between the individual’s narrative and the objective findings and termed first-person neuroscience.
The evolving understanding of pain as a multidimensional and multisensory experience sounds complex but in fact creates opportunity to tackle pain in different ways. Knowledge of how we prime the neuroimmune system with prior experiences, by the way we think and perceive the World, and how this blends with our genetic make-up is illuminating. There is no moment in isolation but rather a continuum. On sustaining an injury or feeling pain, this is a point in time when a certain threshold of excitability has been reached, triggering a range of protective responses including pain. The pain directs our attention to an area of the body and motivates behaviours that are congruent with healing and survival. Other responses include activation of the autonomic nervous system and changes in motor patterning. How we respond is down to what the psychoneuroimmune systems do to protect us. We feel the effects, sometimes subtly and sometimes like a tidal wave as they take hold. What happens next will depend on what has happened before, how we think and behave, our genetics, the context around the injury or when the pain starts and the state of the neuroimmune system at that point to name but a few. For simplicity I have named responders as the ’get betterers’ and the ’persisters’.
The ’get betterers’ are those who sustain injuries or develop pain (these are different constructs) and simply get better. Sometimes they seek advice and have treatment and sometimes they just modify their activities. The end result is a reduction in sensitivity and a return to normal life. Notably lacking in the early stages of the injury are any signs of catastrophising and excess vigilance to the injured area. Often these individuals have had prior injuries that have successfully resolved, have an optimistic outlook for the new injury and are not too bothered by the inconvenience. Clearly this is a simplified description of a necessarily complex interplay of physiology, behaviour, belief and character.
The ‘persisters’ often tell a different story. The context of the injury maybe traumatic, the injury may have been poorly
managed and could have created a great deal of fear and anxiety (the latter could be pre-existing). The early focus is surrounded by catastrophic thinking in some cases, accompanied by a set of protective behaviours that although useful as an aid to healing in the acute phase, become problematic as time progresses. Often the early sensitivity and pain are intense and strong, the signals of danger bombarding the neuroimmune system and triggering changes in the properties of these neurons. Subsequent signals are amplified so that normal stimuli (touch, movement) hurt and those that would normally be painful are even more so.
A growing body of evidence suggests that at the point of injury, if the nervous system has been primed by epigenetic factors, the response could be overblown and persist due to the subsequent ‘rewiring’ in the central nervous system. Epigenetic factors are those that are as a result of the effects of the environment upon our genetic make-up. The good news regarding epigenetic effects is that they seem to be reversible if we create the right situation. This is why the thinking around the treatment of chronic or persisting pain must be different.
In a persisting pain state we are not dealing with the acute response to an injury that is unpleasant but normal and necessary. Instead we are tackling an emergent experience (the pain) from the ‘self’ (body) that is underpinned by a complex interplay between the body systems that include the neuroimmune, endocrine and autonomic. This takes a different and multidimensional approach.
How do we do this? We look at the individual and the physical-cognitive-emotional dimensions of the condition and pain. Tackling the problem requires strategies and therapies that target beliefs, behaviours, cognitions, stress, physical health (e.g. tissue mobility, strength etc), motor planning and control (i.e. normal movement), restoration of function, resilience and confidence to name a few.
Following an injury the tissues go through a healing process. Pain and other symptoms can certainly persist beyond the healing time and this is due to changes in the neuroimmune system. There can be little to see on a scan or x-ray in many cases (termed ‘medically unexplained symptoms’, i.e. no pathology or abnormality seen yet the symptoms are fully lived. However, the neuroimmune system is very plastic (neuroplasticity), a feature that allows for adaptation and learning. We can use this to our advantage and create the opportunity to change the experience of pain and ease the symptoms concurrent with shifting our relationship with pain by changing the meaning. Reducing the threat value of pain (moving from fear/anxiety to ‘so what’) has an enormous impact upon the perception of pain, in a sense disarming the experience.
In summary, some people recover from an injury or painful condition and return to full activities at home, work and in their chosen sports whilst others have difficulty. The latter group require a very different model of care to tackle the problem of chronicity and recurrence, this model being comprehensive, addressing the physical-cognitive-emotional dimensions of pain. Naturally more complex as we must consider (in no particular order) neuroimmune development and priming, genetics, epigenetics, existing beliefs, culture, stressors, altered processing of nociceptive signals, sensory and motor cortical representation changes, altered body sense and the impact upon ‘self’ and lifestyle. Constructing a treatment programme around these factors creates the opportunity for change, the development of wellness and the optimisation of performance.