Anklosing spondylitis is what?

Arthritic condition. Ankylosing spondylitis is a severe disorder that causes fusion of the vertebrae in the spine. The bones are brittle and easily broken. Commonly called "bamboo spine", the spine is prone to fracture.
Inflammatory spine. Ankylosing spondylitis (as) is an inflammatory form of arthritis that tends to strike the low back and sometimes the hips. In severe or long-duration cases, the vertebrae in the spine can begin to fuse together. Some patients are very significantly helped by medication.