Stiffness or, more often, fusion of a joint.

Ankylosing Spondylitis a.k.a Radiographic sacroilitis(r-axSpA)

Axial Spondyloarthritis - formerly called AS. Classified into two categories: r-axSpA and nr-axSpA

Inflammation of a digit (either finger or toe). The affected fingers and toes swell up into a sausage shape and can become painful.

Inflammation of the entheses, the sites where tendons or ligaments insert into the bone.

Inflammatory bowel disease associated Arthritis

Non-radiographic Axial Spondyloarthritis - no definitive sacroiliitis changes seen on X ray of sacroiliac joint

Non steroidal anti-inflammatory drugs - first line of treatment for axSpA

Psoriatic arthritis

Radiographic Axial Spondyloarthritis - definitive sacroilits changes seen on X ray of sacroilic joint

Reactive Arthritis

Inflammation of the sacroiliac joint

Spondyloarthritis - an umbrella term that includes axial and peripheral spondyloarthritis

Calcifications or heterotopic ossifications inside a spinal ligament or of the annulus fibrosus seen in only a limited number of conditions like radiographic axSpA or ankylosing spondylitis.