title: Joint counts in inflammatory arthritis.
abstract: OBJECTIVE
  Counting the number of tender and swollen joints is an important aspect of assessing patients with an inflammatory arthritis. We provide a comprehensive overview of joint counts in inflammatory arthritis. This spans how they are undertaken, their use in clinical and research settings, their limitations and standardisation and who can perform them.
  
  
  METHODS
  We reviewed the literature surrounding joint counts in inflammatory arthropathies, with a specific focus on rheumatoid arthritis (RA).
  
  
  RESULTS
  The current widely used joint count assesses 28 peripheral joints. In RA these are usually incorporated in a composite score of disease activity, termed the disease activity score on a 28-joint count (DAS28). Assessing 28 joints has a strong 'floor-effect' with most patients in routine practice having low swollen and tender joint counts. Marked between-observer variation exists in joint count scores; although the variation in tender joint counts can be reduced by standardised training its impact on swollen joint counts is uncertain. Fibromyalgia can have a marked impact on tender joint count scores, resulting in a disproportionately high tender joint count to swollen joint count ratio. Although there is evidence that patient-assessed tender joint counts correlate well with those undertaken by physicians, patients are limited assessors of synovitis.
  
  
  CONCLUSIONS
  Although joint counts provide an important objective measure of disease activity in clinical practice, they have a number of limitations. Future research may provide a more robust clinical assessment for disease activity in inflammatory arthropathies, which overcomes these issues.
authors.affiliation: Academic Department of Rheumatology, Centre for Molecular and Cellular Biology of Inflammation, 1st Floor, New Hunt's House, Guy's Campus, King's College London, Great Maze Pond, London, SE1 1UL, UK. ian.scott@kcl.ac.uk.
authors.forename: I C
authors.initials: IC
authors.lastname: Scott
authors.forename: D L
authors.initials: DL
authors.lastname: Scott
mesh_terms: D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007596:Joints / Q000473:pathology* / Q000503:physiopathology; D015588:Observer Variation; D010147:Pain Measurement; D010808:Physical Examination / Q000592:standards; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012720:Severity of Illness Index