Cervical myelopathy associated with congenital C2/3 canal stenosis and deficiencies of the posterior arch of the atlas and laminae of the axis: case report and review of the literature

Abstract

Study design: A case report of a young male suffering progressive neurologic dysfunction associated with a previously unreported combination of structural bony abnormalities. A review of the literature is also presented.

Objective: To describe a unique presentation of cervical myelopathy related to posterior deficiencies of the atlas and axis, and to report on the successful management of this case.

Summary of background data: Cervical myelopathy from congenital canal stenosis is an uncommon presentation in the adolescent age group, especially affecting the C2/3 level. Aplasia of the atlas is a rare, although well-reported phenomena. Defects of the posterior elements of the axis are similarly uncommon. A combination of the 2 defects in the 1 patient has not previously been recorded.

Methods: A 14-year-old Caucasian male with no history of trauma or neck pain presented with progressive cervical myelopathy over a 2-year period. Plain radiograph and computed tomography revealed congenital aplasia of the posterior arch of the atlas and bilateral cleft defects of the laminae of the axis resulting in a free floating C2 spinous process. Magnetic resonance imaging showed T1 and T2 signal abnormality at the C2-C3 level, with C2/3 congenital canal stenosis and mild disc protrusion.

Results: The patient underwent a posterior decompression and lateral mass fixation at the C2/3 articulation to preserve maximal motion segments. At 12-month follow-up, the patient's cervical myelopathy had improved in terms of gait dysfunction and hemiparesis. Fusion was evident across the posterior lateral mass on radiologic investigation.

Conclusion: Posterior deficiencies of the atlas and axis are rare occurrences in isolation, let alone in the 1 patient. This report broadens the radiographic differential diagnosis of patients presenting with cervical myelopathy, which has been associated with congenital posterior C2 anomalies in only a handful of patients. Surgery is an appropriate option for these patients faced with progressive neurologic dysfunction.