The clinical reasoning of pain by experienced musculoskeletal physiotherapists

Abstract

There is currently no research within Physiotherapy to explain the extent to which current theories and models of pain influence clinicians’ reasoning related to clinical presentations of pain. The purpose of this qualitative study was to investigate the clinical reasoning of experienced musculoskeletal physiotherapists in relation to three different presentations of pain.

A qualitative multiple-case studies method was used in this study. A purposive sample of seven experienced musculoskeletal physiotherapists viewed three videotaped patient-therapist clinical interviews describing three different pain presentations. An audio taped, semi-structured interview was carried out with each participant during which the participants were encouraged to verbalize their thoughts regarding aspects of each patient's pain presentation. All interviews were subsequently transcribed, coded and analysed.

Results showed a dynamic, multidimensional nature to the therapists’ clinical reasoning, which was found to be grounded in a number of established models of pain. Five main categories of pain-based clinical reasoning were identified. These were (i) biomedical, (ii) psychosocial, (iii) pain mechanisms, (iv) chronicity and (v) irritability/severity. Reasoning within these categories influenced therapists’ prognostic decision-making as well as the planning of physical assessments and treatment.

The clinical reasoning of pain by the participants in this study appeared to reflect the integration of diverse models and theories of pain into current clinical practice. Mechanisms-based clinical reasoning has not been previously observed amongst physiotherapists.

Introduction

It has been suggested that pain is the main symptom with which patients present to musculoskeletal physiotherapists (Watson, 1996; Cheing and Cheung, 2002). It has also been suggested that within physiotherapy considerable importance is placed upon the patient's report of pain, as elicited through the patient-therapist clinical interview, by physiotherapists when reasoning and decision-making with regard to its nature and treatment (Main and Watson, 1999).

Epidemiological studies and reviews suggest that between 10% and 20% of the populations of industrialized western societies have a persistent pain problem (Magni et al., 1993; Verhaak et al., 1998; Pain in Europe, 2003). The personal cost to sufferers of ‘chronic pain’ can be devastating. One in five chronic pain sufferers have lost a job as a result of their pain, and one in five sufferers have been diagnosed with depression as a result of their pain (Pain in Europe, 2003). Financially, the costs to societies both directly (through expenditure on healthcare) and indirectly (through lost productivity and tax revenue and disability compensation) run into the billions (US dollars) (Turk, 2002).

A review of the literature shows a variety of theories and clinically applicable models to account for the experience and presentations of pain. The Cartesian/Medical model and specificity theories of pain explain pain as a direct correlate of physical disease or injury (Melzack and Wall, 1991). The gate control theory of pain (Melzack and Wall, 1965) described the neurophysiological mechanisms of pain transmission and modulation centring on the dorsal horn of the spinal cord. The gate control theory of pain together with more contemporary approaches such as the biopsychosocial model (Waddell, 1998), and mechanisms-based approaches (Jones, 1995; Gifford and Butler, 1997) have contended the usefulness of earlier theories, such as the medical model, by attempting to explain and account for the often variable and inconsistent relationship between pathology and pain.

For physiotherapists, a hypothesis-oriented, mechanisms-based approach to the clinical reasoning and categorization of pain has been proposed (Jones, 1995; Gifford and Butler, 1997). This approach suggests that clinical presentations of pain may be categorized according to five classes of pain mechanisms: (1) nociceptive, (2) peripheral neurogenic, (3) central pain, (4) autonomic and motor mechanisms and (5) affective mechanisms.

This approach has been based upon the perceived limitations of the medical model of pain and illness and recent advances in understanding of the neurophysiological basis of pain. According to Gifford and Butler (1997) a pain mechanisms approach could aid judgements regarding the assessment, treatment and prognosis of patients’ pain. The ‘mature organism model’ proposed by Gifford (1998) further expanded the mechanisms-based approach by integrating knowledge of the neurophysiological mechanisms of pain with the science of stress biology and the biopsychosocial model of pain and disability. The ‘mature organism model’ describes the numerous and interrelated biological systems and processes involved in the initiation, maintenance and perception of pain together with the physiological and behavioural reactions to it. This type of broad understanding of pain, the model suggests, is required in order that clinical presentations of pain might be better managed.

Whilst the clinical reasoning of pain has not been directly studied in physiotherapy, a limited body of literature exists with respect to the study of pain knowledge amongst physiotherapists and health professionals. Wolff et al. (1991) in their survey of 500 orthopaedic physiotherapists, conducted by postal questionnaire, found specific deficiencies in clinicians’ knowledge regarding pain mechanisms. In addition, 72% of respondents perceived their graduate/entry level of pain education, with respect to pain theory and management, as very inadequate or less than adequate. Moseley (2003) also found health professionals to have poor knowledge of the neurophysiology of pain but that with appropriate training were capable of improving their understanding. Rivett and Higgs (1997), in a study of the hypothesis categories used by 19 manual therapists, found no evidence for clinical reasoning concerning neurophysiological pain mechanisms. Other authors have also highlighted the discrepancy that exists between published information on the neurobiology and psychosociology of pain and the knowledge and actions of clinicians (Woolf and Decosterd, 1999; Champion, 2000).

Theories and models of pain provide a conceptual framework with which to investigate and interpret current methods of clinical reasoning of pain. It has been argued that within manual therapy (Main and Watson, 1999) and medicine generally (Waddell and Main, 1998) clinical reasoning with respect to pain remains dominated by the medical model with its structure/pathology-oriented explanations of pain and disability. However clinical reasoning in relation to pain in physiotherapy practice has not been subject to focused investigative study. The extent to which clinicians incorporate and utilize other theories and models of pain into clinical practice, such as the biopsychosocial model (Waddell and Main, 1998) or mechanism-based methods (Jones, 1995; Gifford and Butler, 1997) has not been studied in physiotherapy.

The aims of this study were:

• To investigate the clinical reasoning processes of experienced musculoskeletal physiotherapists in relation to three different pain presentations.

• To determine how such reasoning may inform or influence other areas of clinical decision-making in physiotherapy.