PAIN “is always a psychological state"(IASP)

BIOMEDICAL MODEL OR BIOMEDICAL DOGMA

“In Science, a model is revised or abandoned when it fails  to account adequately for all data. A dogma, on the other hand, requires that discrepant  data be forced to fit the model or be excluded. Biomedical dogma requires that all disease, including “mental” diseases be conceptualized in terms of derangement of underlying physical mechanisms”. George L.Engel 1977

Even though tissue damage and subsequent nociceptor activity can be seen as a dominant mechanism in acute pain it should be appreciated that psychosocial factors have a powerful role in determining and modifying the implicit physiological outputs and explicit behavioural patterns that are such an important part in recovery.

 In the chronic pain situation,  the pathobiological pain mechanism focus shifts from the tissue and nociceptor mechanisms in the periphery to focus more on maladaptive and widespread reactivity and sensitivity of the whole sampling-scrutinising-output systems.

 As Clinicians that are involved in the diagnosis and management of all benign pain states, we  have two major problems. First, evidence of pathological changes in tissues underlying the painful area and in tissues which can refer pain to the area is often lacking. Secondly, there is a large body of evidence demonstrating tissue pathology in the absence of pain. With this in mind  the relevance of perceived and/or clinically extracted abnormalities in tissues that are painful or that may traditionally refer to the area of pain must be questioned.

It is fundamental that we begin to accept that the status of the tissues as a ‘source’ of the pain, even though still reactive to mechanical testing, is far less relevant as time goes on. . The fact that once an experience is “imprinted” it may be very hard to remove , sheds some light on the reasons why so many therapies and surgical procedures for relieving chronic pain have such poor outcomes. Thus continued focus on a tissue as the pain source reinforces fear of movement and activity, the need to be constantly vigilant for pain and the desire for increasingly expensive passive therapeutic interventions that are yet   to demonstrate convincing efficacy.

On-going pain states should best  be explained to patients in terms of an altered sensitivity state because of altered information processing throughout the system, and not solely a result of damaged and degenerating tissues. Patients must be made aware that focusing, repeating, and giving attention  and value to an experience can promote learning and altered central nervous system /brain processing. This also highlights the need to shift the therapeutic focus from pain relief to functional restoration.

 Individuals who are in pain, and especially those without an adequate explanation or understanding of their pain, may well focus unduly on it and thus maintain habitually open pain ‘gates’ which would otherwise be held closed. It is also important to bear in mind that the unhelpful or maladaptive thoughts and feelings a patient may have, occur not only because of on-going pain and the increasing loss of function, but also due to less tangible aspects such as mismanagement by medicine and other primary care clinicians.

The development of the cognitive–behavioural approach to rehabilitation has led to multidisciplinary pain management programs that promote physical improvement by changing the patients’ cognitive and behavioural response to their pain. The important clinical implication is that if we can positively change the way people feel emotionally, by for instance changing their knowledge and beliefs about their problems or situations, we can beneficially change activity in the output systems .  This does not just mean bringing about changes in observable behaviour but also changes in autonomic, neuroendocrine, and immune activity.

The organic basis of ‘mind over matter’ is very much a scientific reality. This helps patients accept the notion that hurt does not necessarily equate with harm which leads on to the positive message that carefully graded increases in physical activity mean stronger and healthier tissues. This is reinforced when patients achieve improved physical function.

It now seems accepted that cognitive factors need to be considered in the assessment and management of chronic pain. It has become clear to me  that limitations of physical performance  that are identified clinically in patients suffering from chronic pain  may be consequent in part to unhelpful pain cognitions, and therefore may respond to strategies that effect cognitive change. Second, clinical techniques  that involve physical therapies and attribute positive outcomes to the efficacy of physical strategies, should consider that the cognitive effects of treatment may be active components in promoting physical improvement. Finally, information provided to patients can influence clinical assessments.