Atlanto Axial InstabilityAtlanto Axial Instability
The muscles and ligaments which normally hold joints in a stable position may be floppy or loose in people with Down syndrome. This can lead to an abnormally wide range of movement at some joints. This can affect the stability of one of the joints in the neck – the atlanto-axial joint. This is the highest joint in the spinal column and it lies at the base of the skull. The normal movements at this joint are when you nod or shake your head.