No, ankylosing spondylitis (AS) does not always show up on an x-ray. This is because early stages of the condition can be difficult to detect, and the changes to bones and joints can be so subtle that they are not visible on x-ray. In some cases, x-ray images may show changes to the spine, hips, or other joints, but this is not always the case.
In many cases, an x-ray may not reveal any changes because the disease is in its early stages and the damage has not yet become visible. However, as the disease progresses, the damage to the spine and other joints can become more pronounced, and may become visible on x-ray images.
In addition, other imaging tests such as magnetic resonance imaging (MRI) or computed tomography (CT) scans may be used to detect ankylosing spondylitis. These tests are more sensitive and can often detect changes to the spine and other joints that are not visible on x-ray images.
In conclusion, ankylosing spondylitis does not always show up on x-ray images. However, other imaging tests such as MRI and CT scans can often detect the changes associated with the condition.