Spondylo means vertebrae or bones in your back. So, you can see that AS affects the spine. With the progression of disease, the vertebral joints fuse causing the spine to be stiff.
AS affects the areas where the joint capsules, tendons and ligaments attach to the bones. Pain and swelling occur along these “hotspots”. The lower back, the sacroiliac joints, the cervical spine, pelvic bones, the rib joints and the heel. Classic AS involvement.
Many other joints can be involved. The joints of the hip, shoulder, and knee are commonly involved. Involvement of fingers, toes, wrists and jaw, although possible, is not common.
It is a disease of younger people (teen-40s) usually. It is common in men, but science is learning that women have AS frequently, too. It is a major cause of low back pain.
It is an inherited disease. There are many genes involve. The gene HLA-B27 is present in 90% of those who have AS. As in many cases an environmental trigger like an infection activates the genes involved.
AS belongs to a group of inflammatory, arthritic diseases including psoriatic arthritis, reactive arthritis and enteropathic arthritis. This group is called spondyloarthritis (SpA).
AS is the second leading inflammatory arthritis behind RA.
Expanding your horizon
Visit the Spondylitis Association of America website to learn more.
Creaky joints has a good article on women and AS.