Arthropathy and sacro-iliitis in severe psoriasis.

Fifty consecutive adult patients hospitalized for psoriasis were examined. Persistent low back pain, large joint arthropathy, phalangeal joint arthropathy and radiological sacro-iliitis were frequent findings (18-28%), but were not associated with one another. Chest expansion and spinal mobility were not reduced in the patients who had roentgenological sacro-iliitis. Low back pain at night and large joint arthropathy were positively associated. Peripheral arthropathy and roentgenological sacro-iliitis were associated. There was no sex difference in the frequency of signs or symptoms. Four patients (8%) had ankylosing spondylitis. It was concluded that in psoriatic patients, the different signs of joint affection are only partly related.