In this short session, Kay G. Hermann takes a deep dive into the imaging characteristics and pathophysiology of psoriatic arthritis (PsA). The lecture explores how inflammation in PsA differs fundamentally from rheumatoid arthritis — beginning at the entheses rather than the synovium — and how this leads to the hallmark imaging findings radiologists should recognize. Through illustrative examples and case correlations, the video highlights the continuum from enthesitis and osteitis to new bone formation, erosions, and advanced deformities like arthritis mutilans.

Learning Objectives

After watching this video, participants will be able to:

• Differentiate psoriatic arthritis from rheumatoid arthritis based on underlying pathophysiology and imaging patterns.
• Identify key imaging features of enthesitis, osteitis, and periosteal new bone formation.
• Recognize the characteristic combination of bone destruction and proliferation typical of PsA.
• Describe advanced joint changes such as arthritis mutilans and the pencil-in-cup deformity.