Psoriatic arthritis (PsA) is a diverse multifactorial disease with involvement of musculoskeletal system that is generally manifested as monoarthritis, oligoarthritis or polyarthritis. In few patients, it can also affect the axial skeleton.

Bone marrow edema and enthesitis are the most common indications of inflammation. The primary differential diagnosis of PsA is a clinical challenge, mostly as a differential diagnosis from other inflammatory conditions or degenerative diseases of joints.

Joint inflammatory disorders and tendon changes in the area of the extremities and the spine can be visualized with high sensitivity with the use of musculoskeletal sonography, magnetic resonance imaging (MRI) and fluorescence optical imaging (FOI).

The use of MRI has a prognostic value with further radiographic course of the disease, specifically in the initial stages of the disease. Structural damage can also be partially revealed three-dimensionally in peripheral joints and the spine by means of computed tomography (CT) and conventional X ray imaging. High-resolution peripheral quantitative CT (HR-pQCT) can visualize pathophysiological developments and the morphological consequences in early stages of the disease. The values of conventional X ray diagnostics, MRI, CT, musculoskeletal sonography along with the alternative imaging procedures are offered with respect to the diagnostics and prognosis of the development of inflammation in patients with PsA.

Source: Baraliakos X, Kleyer A, Simon D, Köhm M, Ohrndorf S, Sewerin P. Bildgebung bei der Psoriasisarthritis und Aspekte der röntgenologischen Progression [Imaging of psoriatic arthritis and aspects of radiographic progression]. Z Rheumatol. 2020;79(1):40-52. doi:10.1007/s00393-019-00735-9