Introduction: Degenerative cystic lesions of the upper cervical spine are rare and are generally believed to be due to instability. No consensus exists on the management of these lesions in symptomatic and asymptomatic patients. Conservative and surgical strategies have been described. Anterior or posterior surgical approaches with and without decompression and instrumentation have been described

Methods: The PubMed database was searched for all relevant cases and case series describing non-rheumatoid atlantoaxial joint cysts. The following search phrases were used: “cervical AND synovial cyst”, “atlantoaxial AND synovial cyst”, “c1-2 AND synovial cyst”, “c1-c2 AND synovial cyst”, “cervical AND “juxtafacet cyst”, “atlantoaxial AND juxtafacet cyst”, “c1-2 AND juxtafacet cyst”, “c1-c2 AND juxtafacet cyst.” Results were then filtered for studies involving human subjects only and available in english. The results were not limited by publication date. Cases with cysts at other levels, including atlantooccipital cysts, were excluded. Cases with non-cystic lesions were excluded as well.

Results: Total of 67 cases were included (Table 1, Table 2), a posterior approach was used in 28 patients, anterior approach in 32 patients, and a lateral approach in 3 patients. Non-operative management was reported in 4 cases. An unspecified surgical technique was used in 5 cases. Surgical fusion was reported in 38 cases. Resection of the cyst was attempted in 57 cases, of which 34 were interpreted as complete and 14 as subtotal. 25 of 32 anterior surgeries had complete cyst resection versus 7 of 20 posterior approaches. No resection of the cyst was performed in six surgical cases. Posterior instrumentation was performed in 8 cases out of 25 with posterior approach for decompression versus 30 out of 32 cases with anterior decompression.

Conclusions: Atlantoaxial synovial cysts are rare and the optimal surgical approach has not been determined. We conducted a literature review and found a total of 67 other cases of atlantoaxial synovial cysts reported to date in the literature. We attempt to analyze available data and evaluate anterior versus posterior approaches and the need for decompression, amount of cyst resection, and instrumentation.

Patient Care: The optimal treatment for atlantoaxial synovial cysts is a matter of debate. This article illustrates the different approaches for decompression, fusion, both, or neither for treating atlantoaxial synovial cysts.

Learning Objectives: By the conclusion of this session, participants should be able to: 1.Understand the different surgical approaches of atlantoaxial synovial cysts 2.Make informed decisions in choosing anterior versus posterior resection based on anticipated morbidity

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