Atlantoaxial articular degenerative cysts are rare lesions that should be included in the differential diagnosis of those extradural lesions that can cause a ventral or ventrolateral compression of the cervicomedullary junction. They most commonly occur in elderly female patients affected by diffuse arthrosic degeneration of the cervical spine, with or without clear radiological signs of atlantoaxial instability, and have a typical appearance on MRI imaging. Surgery, with direct excision of the cyst and/or a C1-C2 fusion, is the first treatment of choice. Nevertheless, our report points out the possibility of a significant spontaneous regression of these lesions following a simple conservative strategy based on the use of an external cervical brace together with a systemic anti-inflammatory therapy 1).
Later an atlantoaxial intraspinal juxtafacet cyst at the level of the odontoid process was published 2).