Background: In a small percentage of children born with congenital hydrocephalus,
enlargement of the head and the presence of ventriculomegaly may halt and ultimately …

Background: The authors report a unique concomitant occurrence of mental retardation,
hydrocephalus due to aqueductal stenosis, a freely floating atlas (having anterior, posterior …

The authors report the first example of an adult achondroplastic dwarf with progressive
quadriparesis secondary to atlantoaxial subluxation as a consequence of an os …

We report on the case of a 15-year-old adolescent who presented with a transient
paraplegia and hyposensibility of the upper extremities after sustaining a minor hyperflexion …

Purpose To clarify etiology, clinical features, and diagnostic and treatment options of
atlantoaxial dislocation (AAD) due to os odontoideum (OsO) in patients with Down's …

Purpose There are two theories about the origin of os odontoideum: traumatic or congenital.
However, most studies favor the hypothesis of traumatic theory. To emphasize the …

Introduction Os odontoideum refers to a rounded ossicle detached from a hypoplastic
odontoid process at the body of the axis. The aetiology has been debated and believed to …

The present article is not only interesting because it presents and discusses the complex
embryology of the atlas and axis vertebra as well as the possible origin of the os …

An atlantoaxial subluxation from the unstable Os odontoideum by the failure of proper
integrations between the embryological somites might be a commonly reported pathology …

Severe atlantoaxial instability due to os odontoideum in a patient with spastic cerebral palsy
has not been well described. There is no consensus on treatment, particularly with regard to …