The term axial spondyloarthritis covers patients with established structural changes visible on x-ray in sacroiliac joints and/or in the spine (classical ankylosing spondylitis) but also patients with non-radiographic axial spondyloarthritis in whom early inflammatory signs of the disease can only be visualized with magnetic resonance imaging (MRI). The MRI technique plays an important role in the diagnosis of this disease and an early diagnosis is normally based on a combination of clinical, laboratory and imaging parameters. Only non-steroidal anti-inflammatory drugs and TNF-α blockers are effective in the treatment of axial spondyloarthritis. Patients with short disease duration and elevated acute phase reactant levels demonstrate best therapy response and, therefore, should be closely followed-up and consistently treated.