This article, written by a rheumatologist and a radiologist who have been diagnosing ankylosing spondylitis – AS (axial spondyloarthritis) for many years, provides advice on the rational recognition of these diseases. The second part of the article provides information on changes in the spinal column typical of AS / axial spondyloarthritis, which have diagnostic significance and determine the prognosis of the so-called central type of AS.