Pain Pattern Recognition in Primary Care – Mechanism Driven Management Strategies in Physiotherapy
Mechanism Driven Management Strategies in Physiotherapy
Since the demise of the Cartesian philosophy of mind body separation in recent decades and the evolution of integrated multidisciplinary pain evaluation, primary care practitioners are now faced with a complicated care management pathway.
Certainly within the Allied Health Professions there is inadequate undergraduate training in clinical pain physiology and this is likely also reflective of other medical disciplines. The International Association for the study of pain has produced a core curriculum which needs to be adopted on a wider scale. The broader classifications of pain mechanisms have been defined as the following:
- Peripheral neurogenic
- Central ( neuropathic )
These classifications provide an intellectual framework, which allow us to dissect components of pain patterns in order to match the most appropriate rehabilitation strategies. In recent years much emphasis has been placed on the so-called bio-psychosocial model and this has certainly shifted the focus from exhaustive searches for structural, nociceptive drives to explain patient symptom patterns. This has lead to a plethora of psychosocial questionnaires which attempt to predict outcomes and factors which present barriers to effective rehabilitation.
The first practical difficulty we encounter is defining what constitutes a “successful outcome”. These can be classified as:
- Patient orientated outcomes
- Clinician orientated outcomes
- Purchaser orientated outcomes
With regard to low back pain the most commonly used outcome measures are reduced disability, reduction in pain and return to work.
Obviously the waiting factor / relevance of specific outcome measures need to be tailored to individual cases. For example there is little point is using absenteeism or return to work in the case of a legal secretary complaining of an upper quadrant overuse syndrome who still remains at work.
Return to work with moderate levels of discomfort may represent a successful outcome for a construction worker who sustained cervical soft tissue injuries. The issue here is that the care provider and the patient need to have some objective targets with a defined care pathway and rehabilitation milestones to achieve in order to attain these goals.
This is a fairly well accepted philosophy in pain management programmes but unfortunately is not the norm in primary care pain management. Given that the majority of patients present to Physiotherapists, Doctors, and other health care practitioners primarily complaining of pain and loss of function, this is the obvious focus of the clinical examination and subjective history.
The alert clinician should be attempting to match the physical signs with the reported level of dysfunction and the symptom characteristics. Some patients may display overt fear avoidance type behaviour (lethargic movement, cessation of activities of daily living, exuberant verbal pain descriptors, vivid gesticulation and hyper-vigilance) which are fairly evident to the observant clinician.
However, the vast majority of patients present with some degree of physical limitations, specific functional deficits and re-produceable clinical signs. The clinical challenge then becomes one not just of interpreting the source of the physical signs (structure and mechanism) but the wider ramifications of these features for the individual patient. Clearly factors such as pain intensity, pain characteristics, reported level of disability, inherent beliefs systems, fear avoidance beliefs, pain coping styles, socio-economic factors and culture, influence these responses.
From a physiotherapy perspective one of the primary challenges is to integrate these components and deliver a management plan to optimise return to function. In my opinion this constitutes a completely different challenge to patients who enter chronic pain management programmes.
Patients who have failed multiple interventions but who are still willing to commit to some strategies that are likely to improve their function are essentially in a “back’s to the wall” situation where they have nothing to lose. Because of the programme structures patients are exposed to a variety of disciplines (clinical psychology, pharmacology, rehabilitation and pain education) which they would otherwise not be exposed to.
Introducing a patient to the concept of behavioural modification in the acute or sub-acute phase of a musculoskeletal complaint is a completely different proposition and one which many patients are not prepared to accept. The challenge for the physiotherapist then becomes one of how to induce behavioural modification not with direct cognitive strategies but to use movement, manipulative therapy, functional re-education in a way that re-establishes movement patterns or functions which may initially have been painful and which patients still report as been symptomatic.
This is a classic rehabilitation crossroads where the treating therapist ascertains from physical examination that as is appropriate to increase the level of functional loading and yet the patient still displays fear avoidance behaviour. At this point a common pitfall is a breakdown of trust in the relationship between therapist and patient as the patient feels that their concerns are not been addressed, that their pain is been disregarded or that they are suspected of been a malinger.
All pain has a source and a mechanism! Typically the therapist becomes increasingly distressed because of the discrepancy between physical signs and functional capacity with objective pain measures not viable. It is at this crossroads that the therapist / clinician has a number of practical, behavioural modifications techniques at their disposal.
- Is to break the functional movement pattern into individual components to allow the patient to explore new mechanics and responses to individual movements before integrating these in a composite manner, relevant to function.
- Specific physical examination of the painful site before and after performance of a movement. This is very useful practically.
If one can demonstrate that the performance of a movement hasn’t increased muscle spasm, initiated inflammatory joint reaction or produced a comprise in movement then one can use educational strategies to explain what patient’s are feeling if they are still reporting some discomfort and allay any fears about structural disruption/ inflammatory responses.
These are important practical strategies if rehabilitation is seriously attempting to steer individuals towards successive milestones. If at some point the structured progression of functional loading produces an aggravation of symptoms which correlates with a deterioration in physical signs then I believe it is appropriate to look for specific nociceptive drives with specific physical examination and reassess the functional component of the rehabilitation programme.
If patients tend to plateau at this point with consistent aggravation of specific nociceptive drives (specific joint irritation, specific neural irritation or more diffuse pain patterns the physiotherapist must consider cross referral for pain management procedures such as joint or nerve blockade. Whilst this type of cross-disciplinary management is increasing it is still far from satisfactory at a primary care level.
Likewise to improve the outcome of these procedures information from the rehabilitation setting regarding specific sites of irritation and response to loading should certainly be used in planning interventions. One-off assessments with isolated examination of “tender areas” is often not a true reflection of the primary focal pain sites.
Obviously in order to accurately record and quantify this type of information therapists need to have some specific evaluation skills to structurally differentiate the site of symptoms with relevant physical examination techniques. This includes a battery of tests far beyond simple range of movement evaluation.
It requires evaluation of specific joint movement characteristics to identify hyper or hypo mobile segments. It requires detailed examination of muscle interactions to determine if postural mechanisms are potentiating a source of joint irritability. It requires detailed knowledge of normal muscle function in order to ascertain if abnormal patterns of muscle activity are perpetuating myofascial pain syndromes. It requires knowledge of nerve sensitivity provocation tests (mechanical hyperalgesia) in order to determine if there is a peripheral neuropathic component to a patient’s pain pattern and also to determine the site/sites of neural irritability.
It also requires therapists to recognise when symptom patterns are no longer compatible with localised nociceptive mechanisms (hyperpathia, symptom site fluctuation, non-mechanical provocation, bilaterallity, dysathesia, and diffuse hyperalgesic states).
Recognition of pain patterns which are evolving from a localised structural tissue irritation to a more diffuse centralised pain state is absolutely imperative if chronicity is to be reduced. In practical terms this requires physiotherapists to be able to liase with general practitioners and pain management teams to switch to centrally acting medications as required.
The practicalities of referral to pain management facilities often mean many months of waiting with increasing time to establish patterns of potentially irreversible neurplastic/ behavioural change. The search for more specific molecular mechanisms of pain such as abnormalities in the activation of NMDA receptors, elevation of nitric oxide levels, lowered serotonin (5HT) are some of the biological markers which are being used in some chronic pain investigations in an attempt to match therapeutic drugs to specific mechanisms. Whether these become tools available in primary care or exclusively in chronic pain management clinics remains to be seen.
In summary given that chronic pain is essentially a management issue as opposed to a cure the fundamental objective of primary care practitioners should be proactive prevention in the initial management phase.
Dublin Physiotherapy Clinic
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Ballycoolin. Dublin 11
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