Methods: This is a report of a 63-year-old woman with a retrodental fibrocartilaginous mass and myelopathy. Objective: To describe the pathophysiology of the retrodental fibrocartilaginous mass formation and its association with the C2-C3 disc.

Background: High cervical disc protrusion is an uncommon condition and presents even more rarely as a craniovertebral junction mass with spinal cord compression. Uncertainty remains regarding the etiology of its formation in the retrodental region.

Methods: The patient underwent surgical intervention with transoral decompression and posterior C1-C2 skeletal fusion with bony graft.

Results: On the basis of dynamic plain radiographs, magnetic resonance imaging, and surgical pathology, the origin of the mass may have been the C2-C3 disc.

Conclusions: We hypothesized that the mechanism underlying the posterior odontoid fibrocartilaginous mass with spinal cord involvement most likely originate upward migration of the C2-C3 annulus fragment to the atlantoaxial joint as a result of aging. Secondary fibrocartilaginous metaplasia plays a major role in creating such disc-like material. To prevent unrecoverable myelopathy, early detection and anterior decompression with posterior C1-C2 skeletal fixation and bony fusion are the best treatment methods.