Towards a uniform definition for the centralisation phenomenon

Abstract

The focus of this PhD project is on symptom centralisation. Its primary objectives were to establish a standard operational definition of centralisation and evaluate its inter-rater reliability in neck pain. Two systematic reviews on the reliability and prognostic value of clinically induced symptom responses in spinal pain (Chapters 2 and 3) showed that although the potential usefulness of centralisation has been demonstrated in low back pain, concern has been expressed about the observed inconsistency in reported definitions, and the scarcity of studies in neck pain. A Delphi survey of experts (Chapter 4) assisted in the development of a uniform operational definition for centralisation and the identification of future research questions. Centralisation was generally defined as the progressive and stable reduction of the most distal presenting pain towards the spine midline in response to standardised spinal loading strategies. The support by the Delphi panel of a broader definition allowed for a multitude of different ways of testing to be included in the assessment procedure which may offer some flexibility to clinicians assessing, classifying and managing different spinal pain presentations across different countries. Although the reliability of identifying centralisation was acceptable, high levels of reliability were not demonstrated (Chapter 5). However, reliability was greater for the pair of physiotherapists with prior experience and formal extensive training in symptom response assessment. Therefore, the optimal type and amount of training for eliciting and interpreting centralisation and the effect of procedural variations on testing the outcomes of individuals who centralise require urgent investigation. The prognostic and management value of centralisation are also unknown. This investigation may pave the way for the standardisation of centralisation as a physical sign and stimulate interest for further study of potential sub-groups and classification of spinal syndromes