Both psoriatic arthritis and psoriasis are chronic diseases that worsen over time. However, you might have periods when your symptoms improve or go away temporarily. Psoriatic arthritis can affect joints on one or both sides of your body. The signs and symptoms of psoriatic arthritis often resemble those of rheumatoid arthritis. Both diseases cause joints to become painful, swollen and warm to the touch. However, psoriatic arthritis is more likely to also cause: 
Swollen fingers and toes. Psoriatic arthritis can cause a painful, sausage-like swelling of your fingers and toes.
Foot pain. Psoriatic arthritis can also cause pain at the points where tendons and ligaments attach to your bones — especially at the back of your heel (Achilles tendinitis) or in the sole of your foot (plantar fasciitis).
Lower back pain. Some people develop a condition called spondylitis as a result of psoriatic arthritis. Spondylitis mainly causes inflammation of the joints between the vertebrae of your spine and in the joints between your spine and pelvis (sacroiliitis).
Nail changes. Nails can form tiny dents (pits), crumble or separate from the nail beds.
Eye inflammation. Uveitis can cause eye pain, redness and blurry vision. If untreated, uveitis can lead to vision loss.
