Arthritis of the sacro-iliac joints in patients with psoriasis.

In a series of 58 patients with psoriasis and skin involvement in the absence of any symptoms of an associated joint or bone disease, 49 individuals had definite signs of an arthritis of the sacro-iliac joints, while only slight changes were present in the others. The authors reached the conclusions that arthritis of the sacro-iliac joints occurs in all patients with psoriasis, without any exceptions; and thus not only in those who have simultaneous symptoms of bone or joint disease, which are well known in psoriasis, but equally in those in whom the clinical symptoms are missing.