title: Periodontoid disc herniation vs. degenerated ligaments presenting as extradural mass.
authors.forename: H A
authors.initials: HA
authors.lastname: Crockard
mesh_terms: D002574:Cervical Vertebrae / Q000473:pathology*; D003937:Diagnosis, Differential; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000175:diagnosis* / Q000601:surgery; D008023:Ligaments, Articular / Q000473:pathology* / Q000601:surgery; D009809:Odontoid Process / Q000473:pathology* / Q000601:surgery; D013122:Spinal Diseases / Q000175:diagnosis* / Q000601:surgery