Spondylitis. Magnetic resonance imaging (MRI) scan of a sagittal (side) section through the lower spine of a 63-year-old patient suffering from spondylitis. The front of the body is at left. Intervertebral discs (black) separate the lumbar vertebrae (bones, blue). The space between vertebrae L2 and L3 (upper left) has narrowed, due to inflammation of the joint (spondylitis). Part of the joint is compressing the spinal cord (white, top centre to bottom right). Spondylitis causes pain and restriction of movement. Treatment includes physical therapy and anti- inflammatory drugs. In severe cases, surgery can relieve pressure on the spinal canal.