Psoriatic arthritis is an inflammatory arthritis associated with psori
asis, which is usually negative for rheumatoid factor. The disease dis
plays a wide spectrum of articular and periarticular features which ma
y progress with time. Although psoriatic arthritis was thought to be a
benign condition, it is now clear that up to 20% of patients progress
to significant joint damage and functional disability. Recently, seve
ral predictors for progression have been described and suggest the nee
d for earlier, more aggressive, use of therapy in these patients. The
ideal treatment for psoriatic arthritis is unclear, and few randomised
controlled trials have been reported to date in this condition. Prosp
ective evaluation of the treatment of early disease is now required to
assess the effect of current and future therapies on the clinical, ra
diological and functional outcomes of this condition.