Mechanisms-based classifications of musculoskeletal pain: part 1 of 3: symptoms and signs of central sensitisation in patients with low back (± leg) pain
Five pages on PainSci cite Smart 2012: 1. The Complete Guide to Patellofemoral Pain Syndrome 2. Complete Guide to Plantar Fasciitis 3. The Complete Guide to Neck Pain & Cricks 4. Sensitization in Chronic Pain 5. Complete Guide to Frozen Shoulder
PainSci commentary on Smart 2012: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided wherever possible.
A huge, three-part paper about an experiment designed to confirm signs and symptoms of central sensitisation — pain driven by the central nervous system, rather than by trouble in tissues — in 464 patients with low back pain (and/or sciatica). Patients were categorized based on “experienced clinical judgement” of the possible cause of their pain. A checklist of clinical criteria for centralized pain was completed for each one. Analysis revealed a cluster of three symptoms and one sign that predicted centralized pain with good consistency between clinicians:
- Pain out of proportion to any apparent injury
- Unpredictable responses to aggravating and relieving factors
- Poor confidence, negative emotions, and beliefs about the pain (e.g. catastrophizing)
- Tenderness of irrelevant anatomy (e.g. sore parts that “shouldn’t” be sore because they are unlikely to be related to any tissue problem)
This summary is based on the abstract only, and probably needs refinement based on a full read (pending).
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
As a mechanisms-based classification of pain 'central sensitisation pain' (CSP) refers to pain arising from a dominance of neurophysiological dysfunction within the central nervous system. Symptoms and signs associated with an assumed dominance of CSP in patients attending for physiotherapy have not been extensively studied. The purpose of this study was to identify symptoms and signs associated with a clinical classification of CSP in patients with low back (± leg) pain. Using a cross-sectional, between-subjects design; four hundred and sixty-four patients with low back (± leg) pain were assessed using a standardised assessment protocol. Patients' pain was assigned a mechanisms-based classification based on experienced clinical judgement. Clinicians then completed a clinical criteria checklist specifying the presence or absence of various clinical criteria. A binary logistic regression analysis with Bayesian model averaging identified a cluster of three symptoms and one sign predictive of CSP, including: 'Disproportionate, non-mechanical, unpredictable pattern of pain provocation in response to multiple/non-specific aggravating/easing factors', 'Pain disproportionate to the nature and extent of injury or pathology', 'Strong association with maladaptive psychosocial factors (e.g. negative emotions, poor self-efficacy, maladaptive beliefs and pain behaviours)' and 'Diffuse/non-anatomic areas of pain/tenderness on palpation'. This cluster was found to have high levels of classification accuracy (sensitivity 91.8%, 95% confidence interval (CI): 84.5-96.4; specificity 97.7%, 95% CI: 95.6-99.0). Pattern recognition of this empirically-derived cluster of symptoms and signs may help clinicians identify an assumed dominance of CSP in patients with low back pain disorders in a way that might usefully inform their management.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- Classical Conditioning Fails to Elicit Allodynia in an Experimental Study with Healthy Humans. Madden 2017 Pain Med.
- Topical glyceryl trinitrate (GTN) and eccentric exercises in the treatment of mid-portion achilles tendinopathy (the NEAT trial): a randomised double-blind placebo-controlled trial. Kirwan 2024 Br J Sports Med.
- Placebo analgesia in physical and psychological interventions: Systematic review and meta-analysis of three-armed trials. Hohenschurz-Schmidt 2024 Eur J Pain.
- Recovery trajectories in common musculoskeletal complaints by diagnosis contra prognostic phenotypes. Aasdahl 2021 BMC Musculoskelet Disord.
- Cannabidiol (CBD) products for pain: ineffective, expensive, and with potential harms. Moore 2023 J Pain.