Atlantooccipital fusion or Occipitalization of atlas is the most common congenital abnormality of upper cervical spine. It means partial or complete congenital fusion between the atlas and the base of the occiput.
The severity ranges from a complete bony fusion to a bony bridge or even a fibrous band. Occipitalization occurs because of failure of segmentation between the fourth occipital sclerotome and the first spinal sclerotome.
The incidence has been reported to be 1.4 to 2.5 per 1000 children. It affects both sexes equally. and affects males and females equally.
In 70% of the cases atlantooccipital fusion is associated with congenital fusion between C2 and C3. Other associated congenital anomalies are
- Kyphosis and scoliosis
- Anomalies of the jaw
- Incomplete cleft of the nasal cartilage
- Cleft palate
- External ear deformities
- Cervical ribs
- Urinary tract anomalies
These patients have [Read more...]