Atlantotaxial instability is a condition of the cervical spine (e.g. the neck) that affects about 17% of persons with Down's Syndrome.
The muscles and ligaments around the very first bone on the top of the spine (the atlas) and the bone underneath it (the axis) are lax. This causes weakness of and displacement between those 2 bones in the neck.
The condition may cause damage to the spinal cord if the neck is forcefully flexed or extended. Therefore, it may restrict some exercise and athletic activities. With precaution, however, atlantotaxial instability does not preclude athletic activity on the part of people with Down's Syndrome.
Atlantotaxial instability can only be confirmed by X-ray.
Last Updated: February 1, 2006

