Psoriatic Arthritis BasicsScientists believe psoriatic arthritis is caused by a combination of environment, genetics and immune system strength. Symptoms include crumbling, discoloration, pitting or thickening of the nails; difficulty moving immediately after rising; eye redness and pain; lower back or neck pain; stiffness, or tenderness in the joints and swelling around the affected areas.
Some sufferers experience enthesitis -- swelling around the tendons of the affected area. Others get tenosynovitis, where the tendon's surrounding sheath becomes inflamed. Another is dactylitis, which makes fingers and toes swell.
Psoriatic arthritis gravitates to some joints more than others. Mutilans shortens or deforms finger or toe joints. Asymmetric oligorarthritis occurs on one side of the body, affecting fewer than five joints. Distal arthritis attacks the tips of fingers and toes. Spondyloarthropathy prefers the joints of the spine. Polyarthritis affects multiple joints on both sides of the body.