Psoriatric Arthritis

Important points on Psoriatic Arthritis from Harrison 18th edition

1) Nail changes occur in 90% of patients with psoriatic arthritis, compared
to 40% in psoriatic patients without arthritis.
2) The subtype of psoriasis associated with severe arthritis is Pustular
Psoariasis.
3) Shortening of digitis(telescoping) because of underlying osteolysis is
characteristic of psoriatic arthritis.
4) Associated nail changes are-pitting, horizontal ridging, onycholysis, yellowish
discoloration of nail margins, dystrophic hyperkeratosis.
5) Distal interphalangeal joint involvement produces the classic “pencil in cup”
deformity.
6) The “Wright and Moll classification” as well as “CASPAR Criteria” are for Psoriatic Arthritis