Reactive arthritis of the joints is a non-purulent "sterile" inflammatory disease of the musculoskeletal system, induced by infections of extra-articular localization, primarily of the genitourinary or intestinal tract. Along with ankylosing spondylitis and psoriatic joint damage, reactive arthritis is included in the group of seronegative spondyloarthritis, which is associated with damage to the sacroiliac joints and spine.