Overview
- Atlanto-Occipital Dislocations – Children, Lateral Neck XR, Power’s Ratio > 1, craniocervical fusion
- Atlanto-Axial Dislocation – Rheum, Down Syndrome, Lateral Neck XR, ADI > 3.5 unstable
- Atlanto-Axial Subluxation – Grisel’s Syndrome, dynamic CT
- Unilateral Facet Dislocation – reverse hamburger sign; closed reduction
- Bilateral Facet Dislocation – reverse hamburger sign; surgery
Risk Factors/Mechanism
Diagnosis
Management
Atlanto-Occipital Dislocation
High energy trauma results in a tear of the tectorial membrane and alar ligament at the craniocervical junction
Lateral Neck X-ray
Powers Ratio = greater than 1
basion to C1 arch
opisthion to C1 arch
Cranio‐cervical fusion with internal fixation
Atlanto-Axial Dislocation
Damage to transverse ligament allows C1 (atlas) to move forward resulting in an increased atlanto dens interval (ADI)
More common in Down Syndrome, Rheumatoid Arthritis
Atlanto-Dens Interval
> 3.5mm considered unstable
> 10mm indicates surgery in RA
posterior occipitocervical/C1–C2 fusion after transoral odontoidectomy or periodontoid tissue release
Atlanto-Axial Rotary Subluxation
Grisel Syndrome – inflammatory or infectious process of the atlanta-axial joint results in atlanto-axial subluxation
dynamic CT is the gold standard
- Soft collar, therapy, NSAIDS and stretching exercise program
- home head halter traction therapy (5lbs)
Unilateral Facet Dislocation
- most frequently missed cervical spine injury x-ray
- leads to ~25% subluxation on xray
- associated with monoradiculopathy that improves with traction
CT Spine that shows reverse hamburger sign
Cervical orthosis or external immobilization (6-12 weeks)
Bilateral Facet Dislocation
- leads to ~50% subluxation on xray
- often associated with significant spinal cord injury
CT Spine that shows reverse hamburger sign
Emergent closed reduction if neuro deficits, if not then get MRI
Works Referenced
- Atlanto-Occipital Dislocation
- Atlanto-occipital dislocation. World J Orthop 2015; 6(2): 236-243
- Traumatic atlanto-occipital dislocation (AOD) Korean J Spine. 2012;9:85–91.
- Atlantoaxial Dislocation
- AtlantoAxial Rotary Subluxation
- Grisel Syndrome: Pathophysiological Evidence from Magnetic Resonance Imaging Findings
- Grisel’s syndrome: An unusual cause of Torticollis
- Non-traumatic Atlanto-axial Rotatory Subluxation- Grisels Syndrome Case Report and Literature Review
- A Case of Grisel Syndrome Showing No Underlying Laxity of the Atlanto-axial Joint
- Grisel Syndrome: Pathophysiological Evidence from Magnetic Resonance Imaging Findings
- Facet Dislocations
- Signs in Imaging – The Naked Facet Sign
- Food signs in radiology
- CT Patterns of Facet Fracture Dislocations in the Thoracolumbar Region
- Handbook of Neurosurgery 7th Ed 28. Spine injuries
- Video – Cervical Facet Fractures and Dislocations – Presented by Michael Y. Wang, MD, FAANS, of the University of Miami
- Reduction of Locked Cervical Facets: Manual, Anterior Open, Posterior Open
- Spinal Injuries
- Ortho Bullets – Cervical Facet Dislocations & Fractures
- Neuroradiology on the net – bilateral jumped facets
- Neupsy Key –Cervical Facet Dislocations