Abstract
Authors report three cases of psoriatic onycho-periostitis (great toe in two cases, thumb in one case). In a recent study, they demonstrated that osteoperiostitis of the distal phalanx of the great toe was significantly more frequent in patients with psoriatic arthritis than in other groups (cutaneous psoriasis, rheumatoid arthritis, spondylarthropathy, connective tissue diseases, and control subjects), suggesting that the existence of osteoperiostitis of the distal phalanx of the great toe is valuable for the diagnosis of psoriatic arthropathy.