Psoriatic arthritis
PsAPsoriatic arthritis is an inflammatory joint disease that occurs in some people with psoriasis, affecting joints, tendons, the spine and nails.
It typically appears years after skin symptoms, though joint problems occasionally come first. Features include swollen, stiff and painful joints, sausage-like swelling of entire fingers or toes, pain where tendons attach to bone such as the heel, and pitted or lifted nails. The pattern may be asymmetrical, involve a few large joints, or affect the spine. Fatigue and eye inflammation can accompany it.
Rheumatologists diagnose it from the combination of skin and nail findings, joint examination, imaging and blood tests that are typically negative for the rheumatoid factor seen in rheumatoid arthritis. Early diagnosis matters because untreated inflammation can permanently damage joints. Cannabinoids have been studied in inflammatory arthritis mostly at the laboratory stage, and clinical evidence in psoriatic arthritis is minimal.