Abstract: Objective: To compare the characteristics of arthropathy demonstrated by musculoskeletal ultrasound imaging between the patients with moderate-to-severe psoriasis and the patients with psoriatic arthritis. Methods: The data of the patients with moderate-to-severe psoriasis and psoriatic arthritis (PsA) underwent musculoskeletal ultrasound examination from February 2014 to August 2017 was analyzed retrospectively. The frequency and distribution of enthesitis, synovitis, bone erosion, narrowing of joint space, nail lesions were assessed and compared between the two groups. Results: Compared to 310 moderate-to-severe psoriasis patients, the age was older, the duration of the disease was longer, and the abnormal ultrasonic manifestations of joint pain was more common in 110 psoriatic arthritis patients. Ultrasound imaging showed that 108 (96.4%) patients with PsA and 254 (81.9%) moderate-to-severe psoriasis patients had joint lesions. Conclusion: The frequency of the abnormal ultrasonic manifescations of the joint are high in both patients with moderate-to-severe psoriasis and PsA in this study and the joint examination should be attracted attention in those patients. 

Key words: psoriasis, psoriatic arthritis, ultrasonography