The pattern of musculoskeletal complaints in patients with suspected psoriatic arthritis and their correlation with physical examination and ultrasound.
To describe the pattern of musculoskeletal symptoms and their correlation with clinical and sonographic findings among psoriasis patients with suspected psoriatic arthritis (PsA).Patients with psoriasis and no prior diagnosis of PsA were referred for assessment of their musculoskeletal complaints. The study included the following steps: 1) assessment by an advanced practice physiotherapist; 2) targeted musculoskeletal ultrasound and 3) assessment by a rheumatologist. In addition, patients were asked to complete questionnaires about the nature and duration of their musculoskeletal symptoms and to mark the location of their painful joints on a homunculus. Each patient was classified by a rheumatologist as: “Not PsA”, “Possibly PsA” of “PsA”. Musculoskeletal symptoms and patient-reported outcomes were compared between patients with “PsA” and “possible/not PsA”. Agreement between modalities was assessed using Kappa statistics.203 patients with psoriasis and musculoskeletal symptoms were enrolled (8.8% PsA, 23.6% possible PsA). Patients classified as “PsA” had worse scores on the PsA Impact of Disease (PSAID, p=0.004) and Functional Assessment of Chronic Illness Therapy (FACIT, p=0.02). There was no difference between the two groups in the presence, distribution and duration of musculoskeletal symptoms. Analysis of agreement in physical examination between modalities revealed the strongest agreement between the rheumatologist and physiotherapist (k=0.28). The lowest levels of agreement were found between ultrasound and patient (k=0.08) and physiotherapist and ultrasound (k=0.08).The results of this study suggest that the intensity, rather than the type, duration or distribution of musculoskeletal symptoms is associated with PsA among patients with psoriasis.