Congenital Anomalies of the Craniovertebral Junction

ABSTRACT

Congenital anomalies of the craniovertebral junction (CVJ) include conditions such as basilar invagination, assimilation of the atlas and other segmentation defects, atlantoaxial instability, and bony anomalies of the atlas or axis. They may occur independently or in association with conditions such as Down syndrome and achondroplasia. Although signs and symptoms can present at any time in life, these anomalies may also be asymptomatic and discovered incidentally, which can lead to management dilemmas. This article discusses the commonly encountered CVJ anomalies with reference to pathogenesis, clinical presentation, investigation, and management. Recommended treatment paradigms for common conditions such as atlantoaxial instability and os odontoideum are presented, recognizing that the natural history of these conditions is still incompletely understood.

KEYWORDS

Congenital - craniovertebral junction - anomalies - Down syndrome - achondroplasia

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