title: The joint in psoriatic arthritis.
abstract: Psoriatic arthritis (PsA), a chronic inflammatory joint disease associated with psoriasis, is notable for diversity in disease presentation, course and response to treatment. Equally varied are the types of musculoskeletal involvement which include peripheral and axial joint disease, dactylitis and enthesitis. In this review, we focus on the psoriatic joint and discuss pathways that underlie synovial, cartilage and bone inflammation and highlight key histopathologic features. The pivotal inflammatory mechanisms and pathobiology of PsA parallel findings in other forms of spondyloarthritis but are distinct from disease pathways described in rheumatoid synovitis and bone disease. The diagnosis of PsA from both a clinical and imaging perspective is also discussed.
authors.affiliation: Division of Allergy, Immunology and Rheumatology, University of Rochester Medical Center, Rochester, USA. mahta_mortezavi@urmc.rochester.edu.
authors.forename: Mahta
authors.initials: M
authors.lastname: Mortezavi
authors.affiliation: Division of Allergy, Immunology and Rheumatology, University of Rochester Medical Center, Rochester, USA.
authors.forename: Ralph
authors.initials: R
authors.lastname: Thiele
authors.affiliation: Division of Allergy, Immunology and Rheumatology, University of Rochester Medical Center, Rochester, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Ritchlin
mesh_terms: D000818:Animals; D015535:Arthritis, Psoriatic / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D001175:Arthrography / Q000379:methods; D004195:Disease Models, Animal; D042241:Early Diagnosis; D006801:Humans; D007596:Joints / Q000000981:diagnostic imaging / Q000473:pathology*; D011237:Predictive Value of Tests; D011379:Prognosis; D012720:Severity of Illness Index; D014463:Ultrasonography