====== Mass posterior to the odontoid process ======

[[RA]] [[pannus]]. Involvement of the [[cervical spine]] in RA typically begins early in the disease process and
often parallels the extent of peripheral disease correlating with the degree of hand and wrist
erosion

2. [[retro-odontoid pseudotumor]] 

3. [[pseudogout]]

4. [[psoriatic arthritis]]

5. [[chondrocalcinosis]] (???)