Craniocervical junction disorders

[Greta]

Craniocervical junction disorders are abnormalities of the bones that join the head and neck. (Cranio- means skull, and cervical means neck.)

These disorders may be present at birth or result from injuries or disorders that occur later.
Most commonly, people have neck pain and headache, but if the spinal cord or lowest part of the brain (brain stem) is affected, people may have difficulty sensing vibration, pain, and temperature and may have weak muscles, dizziness, and impaired vision.
Doctors suspect the diagnosis based on symptoms, and magnetic resonance imaging or computed tomography is done to confirm it.
To relieve pressure on the brain, spinal cord, or nerves, doctors use traction or manipulate the head, then immobilize the neck, but sometimes surgery is needed.

The craniocervical junction consists of the bone that forms the base of the skull (occipital bone) and the first two bones in the spine (which are in the neck): the atlas and axis. Disorders that affect the large opening at the bottom of the occipital bone (called the foramen magnum) are a particular concern because important structures pass through this opening. These structures include the lowest part of the brain (brain stem), which connects to the spine, as well as some nerves and blood vessels.
Craniocervical junction disorders may involve bones that are

Fused together
Abnormally formed or underdeveloped
Out of alignment (misaligned)

Misaligned bones may be completely separated (dislocated) or partially misaligned (subluxed).
Craniocervical junction disorders can put pressure on the lower parts of the brain, the top part of the spinal cord, or nearby nerves. The resulting symptoms can be serious. They include paralysis, weakness, and loss of sensation.