Objective and importance: Among masses in the craniovertebral junction causing severe compression of the medulla and upper cervical cord, cases of retro-odontoid disc hernia are extremely rare. We report a case of retro-odontoid disc hernia resulting in severe myelopathy.
Clinical presentation: An 82-year-old man suffered from progressive tetraparesis. Although cervical radiological studies showed marked spondylotic change, no congenital malformations or traumatic lesions were identified. Magnetic resonance imaging disclosed a retro-odontoid soft tissue mass with peripheral enhancement compressing the medulla and the upper cervical cord posteriorly.
Intervention: The patient underwent surgery through the posterior approach. The histopathological examination of the surgical specimen revealed fibrocartilage accompanied by reactive vascular tissue; the mass was diagnosed as a retro-odontoid disc hernia.
Conclusion: In the differential diagnosis of mass lesions compressing the neural structures in the craniovertebral junction, retro-odontoid disc hernia, although extremely rare, should be considered to be one possibility. The posterior approach with wide laminectomies provides a good operative field from which to remove the retro-odontoid mass and is especially adequate for elderly patients, because it is less invasive than other procedures.