This is a radiological diagnosis of a condition related to osteoarthritis.
It is defined as the presence of four or more large anterior osteophytes in vertebral disc spaces in the absence of disc space narrowing.
The commonest sites of osteophyte formation are in the thoracolumbar region.
Osteophytes are found in other joints however the sacroiliac joints are normal (which contrasts with ankylosing spondylitis).
Last reviewed 01/2018