Of 35 patients with CI-C2 dislocations, 37% (13 cases) had a history of rheumatoid arthritis, 11% (4 cases) had trauma as well as rheumatoid arthritis, and 25.7% (9 cases) had severe motor deficit quadriparesis or quadriplegia. One patient, representing 2.8% of the total, had a brain contusion related to closed head trauma.
"Atlantoaxial dislocations: A retrospective study of 35 cases,"
Henry Ford Hospital Medical Journal
: Vol. 25
Available at: https://scholarlycommons.henryford.com/hfhmedjournal/vol25/iss3/13