Differential diagnosis of cervical spine instability

Approach to the differential diagnosis of cervical spine instability:

  • Atlanto axial rotatory subluxation is a rotation of the C1 vertebral body on the C2 vertebral body
  • Atlanto axial instability is excessive anterior translation of the C1 vertebral body on the C2 vertebral body
  • Atlanto occipital instability is excessive posterior translation of the occipital condyles on the lateral masses of the C1 vertebral body
  • Pseudosubluxation of cervical spine is a normal finding in the upper cervical spine and needs to be distinguished from fracture / dislocation