As one of the most common chronic inflammatory skin diseases, psoriasis(Ps) can be intimately associated to psoriatic arthritis (PsA), affecting approximately 1% to 2% of the world's population. About 30% of them will develop into PsA with serious impact on their health-related quality of life.
PsA, characterised by different subsets with varying degree of severity, is a chronic, complicated inflammatory disease.Enthesitis is the prevalent and distinctive feature of PsA.
Musculoskeletal Ultrasound (MSUS) is a valid noninvasive modality, essential to evaluate entheses thickness, enthesophytes, bursitis and bone erosions as well as to disclose vascularisation on tendons through power doppler (PD) assessment. In recent years, more and more attention has been paid to the diagnosis and management of Ps and PsA, owing to its discrimination of identifying subclinical entheses and joint changes.