title: Syringomyelia with irreducible atlantoaxial dislocation, basilar invagination and Chiari I malformation.
abstract: A 27-year-old woman presented with bilateral weakness of her all extremities for 5 years. She had a spastic gait and was unable to ambulate without assistance. Neurologic examination revealed increased deep tendon reflexes and positive pathologic reflexes. Radiographs showed occipitalization of the atlas, C2-C3 congenital fusion and fixed atlantoaxial dislocation with an atlanto-dental interval of 10 mm. MRI demonstrated cervicomedullary junction (CMJ) compression from the odontoid, a Chiari type I malformation, and syringomyelia extending from the foramen magnum to C5. The patient underwent transoral atlantoaxial release followed by posterior internal fixation from the occiput to the axis, which resulted in a significant improvement in motor function in all extremities. Post-operative images showed anatomical reduction of the atlantoaxial joint. However, an MRI performed 8 days following surgery showed a new retro-odontoid pannus had developed that was compressing the spinal cord at CMJ. A follow-up CT scan performed at 6 months post-operatively demonstrated a solid bony fusion between the occiput and C2, while an MRI at that time showed complete resolution of the retro-odontoid soft tissue mass with correction of the Chiari I malformation, and resolution of the syringomyelia. Final follow-up at 2-years revealed an excellent clinical outcome.
authors: Orthopaedic Department, Peking University Third Hospital, No 49. North Garden Street, HaiDian District, 100191 Beijing, China.
authors: Shenglin
authors: S
authors: Wang
authors: Chao
authors: C
authors: Wang
authors: Ming
authors: M
authors: Yan
authors: Haitao
authors: H
authors: Zhou
authors: Liang
authors: L
authors: Jiang
mesh_terms: D000328:Adult; D001139:Arnold-Chiari Malformation / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D001268:Atlanto-Axial Joint / Q000601:surgery*; D019299:Decompression, Surgical; D003937:Diagnosis, Differential; D005260:Female; D005593:Fracture Fixation, Internal; D005684:Gait; D006801:Humans; D004204:Joint Dislocations / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D008279:Magnetic Resonance Imaging; D018908:Muscle Weakness / Q000175:diagnosis; D010985:Platybasia / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D020127:Recovery of Function; D013123:Spinal Fusion; D013595:Syringomyelia / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D016896:Treatment Outcome