Odontoid cervical gout causing atlantoaxial instability: case report.

The authors present a case report of a patient discovered to have a rotatory subluxation of the C1-2 joint and a large retroodontoid pannus with an enhancing lesion in the odontoid process eventually proving to be caused by gout. This patient represented a diagnostic conundrum as she had known prior diagnoses of not only gout but also sarcoidosis and possible rheumatoid arthritis, and was in the demographic range where concern for an oncological process cannot fully be ruled out. Because she presented with signs and symptoms of atlantoaxial instability, she required posterior stabilization to reduce the rotatory subluxation and to stabilize the C1-2 instability. However, despite the presence of a large retroodontoid pannus, she had no evidence of spinal cord compression on physical examination or imaging and did not require an anterior procedure to decompress the pannus. To confirm the diagnosis but avoid additional procedures and morbidity, the authors proceeded with the fusion as well as a posterior biopsy to the retroodontoid pannus and confirmed a diagnosis of gout.