Q: How is psoriatic arthritis different from other types of arthritis?

A: There are several features that distinguish PsA from other forms of arthritis which can include any or some of the following:

• Particular patterns of joints that may be involved.
• One pattern of inflammation is usually in the end joints of fingers, often corresponding with the fingers that have psoriatic nail involvement.
• Involvement of the joints of the spine and sacroiliac joints which is called spondylitis.
• Neck pain and stiffness.
• An entire toe or finger can become swollen or inflamed.
• A tendency for joints to stiffen up and sometimes fuse together.
• The absence of rheumatoid factor in the blood.