Considering the Stress Pain Cycle in Assessment

Original Editor - Kim Jackson Top Contributors - Kim Jackson, George Prudden, Claire Knott and Jess Bell;


Pain stress brain.png

Physiotherapists are trained professionals who, on a daily basis, help clients deal with pain and movement dysfunction.  As the profession has moved towards evidence based practice, the way a client's therapy is delivered has also changed. We are moving away from didactic teaching and anecdotal practices, to providing the client with interventions that are based not only on our clinical experience, but research.[1] This has led to a shift from the biomedical model to a more client centred biopsychosocial approach.  This has been influenced by the recognition that emotional factors such as fear, anxiety and stress can delay and impede the recovery of those suffering from pain. While short term or acute stress can be beneficial, especially in a crisis, persistent or long term (chronic stress) can be physiologically damaging.[2] In order to fully understand the shift in assessment and treatment approaches, it is important to understand stress, as well as how people’s behaviour and fears affect their perception and approach to pain, as well as their participation recovery. 

What is Stress?

Stress is an emotional (and physiological) response to either a known or perceived threat and it can be categorised as either acute or chronic. Acute stress can be positive, particularly in the face of danger as it provokes a fight or flight response. However, stress that is prolonged can be detrimental to our health and well-being.[3] The impact stress has on health has received more attention recently, with the World Health Organisation recognising the need for strategies to help those suffering from various forms of stress. [4] It has also recognised the increasing problem of stress in the work place, stating that it is becoming a worldwide epidemic.[4] To better understand how this impacts physiotherapists, it is important to understand not only the biological and physiological response to stress, but also the relationship between chronic pain and stress and how it can influence individuals.   

Physiological Response to Stress

When we are faced with a stressor, messages that come from our senses are processed in the brain. This information is then sent to amygdala (the area of the brain that is involved with emotions, particularly fear, aggression and pleasure). The first step in this process is for our bodies to determine the severity of the threat, based on our senses, perception and memories.  If the threat is strong and our processing centres decide action is necessary, the hypothalamus is activated.  The hypothalmus is the command centre of the brain and communicates with the rest of the body through the two branches of the autonomic system. The sympathetic nervous system stimulates the adrenal glands releasing adrenaline (epinephrine) and cortisol into the blood stream. This triggers physiological changes which prepare us for action. It also activates the parasympathetic nervous system, which acts to slow down the response (see diagram). However, if the stress is chronic, repeated or persistent, then the responses designed to protect us actually become detrimental to our health (diagram)

Acute Stress - Physiological Response
Acute Stress -Physiological Response
Chronic Stress - Physiological Response

The Relationship between Chronic Pain and Stress

Stress/Pain cycle relationship
It has been established that chronic pain can contribute to stress and also that stress can contribute to chronic pain. The burden of of a long-term illness or disability can put a lot of emotional and financial pressure on a person. For instance, the worry of being unable to work, feeling excluded from activities, and feeling misunderstood can have a negative impact on the way a person sees their role within their family and society. Table 1 shows the link between chronic stress and pain.

Chronic pain affects 1 in 5 adults worldwide[6] and is a debilitating condition that affects not only a person's mobility and function, but can also have an impact on their personal relationships, work experience and finances. Feeling isolated can affect stress levels. Evidence shows that chronic pain and chronic stress release the same chemicals and can result in maladaptive changes in physiology and behaviour.[7] These are not the only factors that determine our response to chronic pain or stress. Our social upbringing and environment can also influence our health and attitude. For instance, people of lower social standing, living in impoverished areas are found to have poorer diets and increased exposure to crime and risky behaviours[8]

As mentioned earlier when discussing stress, it has been established that if a person experiences continued or chronic stress the stress response of flight or fight is not regulated. As a result, a new pathway for stress is developed and new memories associated with fear and behaviour are learnt. Chronic pain follows a similar pattern: movement and pain become associated with further damage although in most cases there is little evidence to support this. In fact, there is often no correlation between pain and the state of the tissues in persistent pain conditions. Moreover, movement and exercise can often be useful strategies in the management of chronic pain.[9] Another link between chronic pain and chronic stress is the change in size of the amygdala; in both the amygdala has been shown to decrease in volume. In a study undertaken to investigate the effects of chronic pain on the brain, 10 patients suffering from hip osteoarthritis were found to have an increase in amygdala size after surgery and the abolition of pain. The study concluded that the changes in the brain are not the cause of the pain but rather a response to pain.[10] It is a complex area of study but there is no doubt that this is a connection between chronic pain and chronic stress; people's attitudes and responses can influence their participation and commitment to their rehabilitation programme. It is far more difficult to encourage a person in pain to exercise and move if they have fear behaviours and are also suffering from the effects of chronic stress.

The effects of stress on the Mind, Body, Emotions and Behaviour

BioMedical vs Biopsychosocial approaches to assessment and treatment

Physiotherapists along with other medical professions are taught to recognise the biological aspect of pain and dysfunction – anatomy, physiology and condition/problem based case studies, in class and in our working environments.[11] 

However, over the past few years the emphasis is changing to use a client-centred approach where treatment is guided by evidence-based practice. Encouraging a client to participate in their recovery is at the core of this approach. When a client's stress, pain and learned behaviours are added to the equation, assessment and treatment can become complicated and definitely unique.  This is outside the scope and teaching of the biomedical model and in 1977 George Engel, a medical internist and psychiatrist, suggested the biopsychosocial mode. This model encourages clinicians to factor in the client's psychological and social experiences as well as the biological aspects of their presenting condition. Low back pain is an area where research has shown adopting a biopsychosocial approach to treatment is effective[12][13]

An assessment which incorporates the biopsychosocial model can be a long and detailed process, which may be daunting. It requires the therapist to ask questions and pay attention not only to pain intensity and movement dysfunction and restrictions, but also to behaviours and beliefs. This can be a complex process and there are factors in place to guide the assessment and subsequent treatments. Physiotherapists are not new to using markers and signs to lead their assessment. A flag system[14] has been developed to help identify risk factors in musculoskeletal disorders. Red flags were first introduced into practice in 1994[14] and are used to identify serious pathology.  Since then other flags have been introduced to highlight potential barriers to treatment and rehabilitation. These flags help guide our management and approach and give insight in how to engage clients and improve treatment outcomes.

Flag system as described by CSP [14]
Flag Introduced Indicators
Red 1994 Serious pathology, eg.
Yellow 1997 Psychosocial factors, eg
Blue 2000 Perception to work, eg
Black 2000 Work conditions inhibiting rehabilitation eg
Orange 2005 Abnormal psychological processes eg alcohol or drug abuse

The Pros and Cons of a Biopsychosocial Approach to assessment and treatment

Cognitive Functional Therapy developed by Peter O’Sullivan to assess and treat low back pain and Therapuetic Neuroscience Education are two new modalities that have been found to be affective when assessing and treating chronic pain conditions.  Both of these approaches have grown from Cognitive Behavioural Therapy principals and although they are aimed at treating chronic pain, the elements that underpin their philosophies can be utilised and adapted for any acute or chronic condition seen within a physiotherapy department. It’s important to remember that a person’s attitude to their acute pain may lead to their pain becoming chronic. A client who is quickly encouraged to adopt a positive attitude and approach to their pain, will have a reduced risk of developing chronic pain.   

Differences between Biomedical and Biopsychosocial Models of Care
Biomedical Model Biopsychosocial Model
Model of Pain and Disease
  • Pain and disease are a result of physiological processes
  • Recognises a link between lifestyle and beliefs in relation to pain and dysfunction
Centres on
  • Condition – disease and pathology
  • Client – experience and function
Responsibility for return to health
  • Medical personnel
  • Client is encouraged to participate in their recovery. Professionals encourage empowerment of client
  • Focuses on condition/disease process
  • Often based on diagnostic findings
  • Focuses on how the condition impacts on clients life. 
  • Takes into account their their social background and psychological experience      
Treatment Plan
  • Goals set on achieving normal parameters through clinical measurements
  • Goals set on clients needs and lifestyle expectations
  • Informing the client of structural changes and deficits
  • Explaining to client that pain does not always equate damage and movement is vital to recovery
Skills utilised
  • Ability to read laboratory led tests ie. Blood pathology, x-rays, MRIs etc
  • Good communication
  • Empathy and understanding
  • Patience
  • Ability to adapt to client’s social background and beliefs
Outcome measures
  • Based on clinicalmedical markers
  • Based on clinical markers and client centred questionnaires

The question is how effective are we at implementing these methods into our everyday practice? Sometimes the evidence, as great as it is, has limitations and barriers.  To be an effective tool, there are certain criteria that have to be met. Understanding the model is of no use if you are not good at observing body language and reading between the lines when clients are talking. As well as these personal skills, there are other barriers. For instance, how do we persuade clients to change their attitude towards pain and movement when they have been given a specific diagnosis and have biomedical treatment expectations? Especially when their learned beliefs have been reinforced by their doctor's advice and internet research. So many people walk into the clinic with preconceived ideas and armed with a wealth of knowledge researched on the internet. If a client is convinced by these preconceptions, how effective can these methods be? If we manage to overcome these barriers and meet a patient presenting with signs of a psychosocial factor (yellow flag), do we feel we have the skills to help modify the client's behaviour or do we refer to another specialist professional?.[14] There are many other barriers and limitations and it is not only our approach to assessment and treatment that needs to change, but the way that physiotherapy is delivered. We can no longer expect to treat multiple clients at one time or limit time slots to 20-30 minutes. We also need to consider privacy and confidentiality - how can we expect clients to speak openly and honestly if they are separated from the next client by a curtain? Physiotherapy has progressed in leaps and bounds over the last few years but to ensure that we continue to provide the best treatment for our clients based on current evidence we need to look at the bigger picture. Changes need to take into account not only our clients' environments and beliefs but also of our colleagues, managers and service providers.



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