<prompt> Answer this question truthfullyWhich type of arthritis is characterized by joint space narrowing, erosions, and periarticular osteopenia on imaging studies such as X-rays, rheumatoid arthritis or osteoarthritis?  <response>: <reason> Rheumatoid arthritis is the type of arthritis that is characterized by joint space narrowing, erosions, and periarticular osteopenia on imaging studies such as X-rays. 