Development of a Retro-Odontoid pseudotumor in the absence of atlantoaxial instability or rheumatoid arthritis Post-Laminoplasty: case report

Abstract

A retro-odontoid pseudotumor (ROP) is commonly associated with atlantoaxial instability (AAI) or rheumatoid arthritis (RA). However, we describe a patient with ROP in the absence of AAI or RA. An 81-year-old man who did not have a history of trauma to the head and neck admitted with neck pain, right upper extremity numbness, lower limb weakness, and walking disturbance. He had a history of C2 dome and C3-7 laminoplasty 10 years ago. Magnetic resonance imaging revealed a retro-odontoid mass with cervical cord compression. Dynamic radiography did not show signs of AAI. He underwent C1 laminectomy without fixation for the ROP. We speculated that the load on C1 and C2 increased because of the progression of kyphosis from C2 to C7 with increases in range of motion, which in turn caused change in the biomechanics of the cervical spine, leading to recurrent partial tear and degradation of the transverse ligament that induced formation of the ROP. Spinal surgeons should keep this complication in mind and inform patients about this potential postoperative complication.

Keywords:

• Retro-odontoid pseudotumor
• laminoplasty of the cervical spine
• cervical kyphosis
• case reports

Disclosure statement

This report has not been published or presented elsewhere in part or in entirety, and is not under consideration by another journal. All authors have approved the manuscript and agreed with submission to your esteemed journal. There are no conflicts of interest to declare.

Ethics and patient consent

Written informed consent was obtained from the patient for publication.