title: Accuracy of musculoskeletal imaging for the diagnosis of polymyalgia rheumatica: systematic review.
abstract: OBJECTIVE
  To review the evidence for accuracy of imaging for diagnosis of polymyalgia rheumatica (PMR).
  
  
  METHODS
  Searches included MEDLINE, EMBASE and PubMed. Evaluations of diagnostic accuracy of imaging tests for PMR were eligible, excluding reports with <10 PMR cases. Two authors independently extracted study data and three authors assessed methodological quality using modified QUADAS-2 criteria.
  
  
  RESULTS
  26 studies of 2370 patients were evaluated: 10 ultrasound scanning studies; 6 MRI studies; 1 USS and MRI study; 7 18-fluorodeoxyglucose-positron emission tomography (PET) studies; 1 plain radiography and 1 technetium scintigraphy study. In four ultrasound studies, subacromial-subdeltoid bursitis had sensitivity 80% (95% CI 55% to 93%) and specificity 68% (95% CI 60% to 75%), whereas bilateral subacromial-subdeltoid bursitis had sensitivity 66% (95% CI 43% to 87%) and specificity 89% (95% CI 66% to 97%). Sensitivity for ultrasound detection of trochanteric bursitis ranged from 21% to 100%. In four ultrasound studies reporting both subacromial-subdeltoid bursitis and glenohumeral synovitis, detection of subacromial-subdeltoid bursitis was more accurate than that of glenohumeral synovitis (p=0.004). MRI and PET/CT revealed additional areas of inflammation in the spine and pelvis, including focal areas between the vertebrae and anterior to the hip joint, but the number of controls with inflammatory disease was inadequate for precise specificity estimates.
  
  
  CONCLUSIONS
  Subacromial-subdeltoid bursitis appears to be the most helpful ultrasound feature for PMR diagnosis, but interpretation is limited by study heterogeneity and methodological issues, including variability in blinding and potential bias due to case-control study designs. Recent MRI and PET/CT case-control studies, with blinded readers, yielded promising data requiring validation within a diagnostic cohort study.
authors.affiliation: Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds , Leeds , UK and NIHR Leeds Musculoskeletal Biomedical Research Unit, UK ; Leeds Teaching Hospitals NHS Trust , Leeds , UK.
authors.forename: Sarah Louise
authors.initials: SL
authors.lastname: Mackie
authors.affiliation: Harrogate and District NHS Foundation Trust , Harrogate , UK ; York Teaching Hospital NHS Foundation Trust , UK.
authors.forename: Gouri
authors.initials: G
authors.lastname: Koduri
authors.affiliation: University of Adelaide, The Queen Elizabeth Hospital , Adelaide , Australia.
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Hill
authors.affiliation: Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds , Leeds , UK and NIHR Leeds Musculoskeletal Biomedical Research Unit, UK ; Leeds Teaching Hospitals NHS Trust , Leeds , UK.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Wakefield
authors.affiliation: Department of Health Services Research and Policy , London School of Hygiene and Tropical Medicine , London , UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Hutchings
authors.affiliation: University of Sydney , Sydney , Australia ; Huntington Disease Service , Westmead Hospital , Sydney , Australia.
authors.forename: Clement
authors.initials: C
authors.lastname: Loy
authors.affiliation: Southend University Hospitals NHS Trust , UK.
authors.forename: Bhaskar
authors.initials: B
authors.lastname: Dasgupta
authors.affiliation: Leeds Institute of Health Sciences, University of Leeds , UK.
authors.forename: Jeremy C
authors.initials: JC
authors.lastname: Wyatt
keywords: Magnetic Resonance Imaging; Polymyalgia Rheumatica; Ultrasonography