"“gull-wing” central erosions are present in erosive OA vs “mouse ears” peripheral bare area erosions in PsA 3,16"
Expected headings
"Associations"
"Plain radiographs"
"Peripheral disease"
"Axial disease"
"While many PsA classification systems exist (see below), there is no gold standard for diagnosis of this condition, which is based on history, examination, biochemical markers, imaging, and observation 11."
"Dermatological features of psoriasis precede arthritis in ~65% (range 60-70%), whereas arthritic symptoms precede dermatological features in 15-20% 9. There is a strong association with nail involvement, particularly for distal interphalangeal joint arthritis 15."
"Three broad phenotypes are described: predominantly peripheral, predominantly axial, and mixed 17. Most commonly, PsA presents as an asymmetrical oligoarthritis with spondylitis; oligoarthritis may progress to polyarthritis in the clinical course of the disease 8,9. Axial involvement is reported in a wide range (25-70%) of patients, reflecting the absence of a consensus agreement on what defines predominantly axial PsA 13,18."
"HLA-B27: may be positive; positivity in axial PsA is higher than in peripheral PsA and the general population, but is lower than in ankylosing spondylitis/axial spondyloarthritis 5,13"
"serum rheumatoid factor: usually seronegative; low titres when positive 4"
"periostitis along the metacarpal and phalangeal shafts; may appear as a periosteal layer of new bone, or as irregular thickening of the cortex itself 1,5"
"cardiac: rhythm disturbances (e.g. left bundle branch block)"