title: Assessment of peripheral enthesitis in the spondylarthropathies by ultrasonography combined with power Doppler: a cross-sectional study.
abstract: OBJECTIVE
  To assess the prevalence and severity of peripheral enthesitis among the different subtypes of spondylarthropathy (SpA) by using ultrasonography (US) in B mode with power Doppler.
  
  
  METHODS
  One hundred sixty-four consecutive patients with SpA (according to the criteria of the European Spondylarthropathy Study Group) and 64 control patients (34 with mechanical low back pain [MBP] and 30 with rheumatoid arthritis [RA]) underwent US examination of major entheses of their limbs. Particular attention was given to the detection of vascularization at the following sites: cortical bone insertion of entheses, junction between tendon and entheses, body of tendon, and bursa.
  
  
  RESULTS
  Abnormal US findings consistent with at least one enthesitis were observed in 161 of 164 SpA patients (98%), affecting 1,131 of 2,952 entheses examined (38%). In contrast, only 132 of 1,152 entheses (11%) were found to be abnormal in 33 of 64 control patients (52%). US enthesitis was most commonly distributed in the distal portion of the lower limbs, irrespective of SpA subtype and of skeletal distribution of clinical symptoms. None of the abnormal entheses in control patients showed vascularization, compared with 916 of 1,131 abnormal entheses in SpA patients (81%), where it was always detected at the cortical bone insertion and sometimes also in the bursa. In SpA patients, the US pattern depended on the clinical presentation, with a higher prevalence of the most severe stages in those with peripheral forms.
  
  
  CONCLUSIONS
  US in B mode combined with power Doppler allowed the detection of peripheral enthesitis in a majority of SpA patients, but not in MBP or RA patients. The presence of entheseal involvement was independent of SpA subtype, but its degree of severity appeared to be greater in peripheral forms. US could be very useful for both the diagnosis and the assessment of SpA activity.
authors.affiliation: Cochin Hospital, INSERM, CNRS, Université René Descartes, AP-HP, Paris, France.
authors.forename: Maria-Antonietta
authors.initials: MA
authors.lastname: D'Agostino
authors.forename: Roula
authors.initials: R
authors.lastname: Said-Nahal
authors.forename: Cécile
authors.initials: C
authors.lastname: Hacquard-Bouder
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Brasseur
authors.forename: Maxime
authors.initials: M
authors.lastname: Dougados
authors.forename: Maxime
authors.initials: M
authors.lastname: Breban
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D017746:Joint Capsule / Q000000981:diagnostic imaging*; D008022:Ligaments / Q000000981:diagnostic imaging; D017116:Low Back Pain / Q000000981:diagnostic imaging / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012720:Severity of Illness Index; D025242:Spondylarthropathies / Q000000981:diagnostic imaging* / Q000453:epidemiology; D052256:Tendinopathy / Q000000981:diagnostic imaging* / Q000453:epidemiology; D013710:Tendons / Q000000981:diagnostic imaging; D018608:Ultrasonography, Doppler / Q000379:methods*