Exuberant transverse ligament degeneration causing high cervical myelopathy.

Two patients with cervical myelopathy and C1-C2 retro-odontoid masses were examined. Preoperative magnetic resonance imaging studies suggested soft tissue pannus, as might be seen in rheumatoid arthritis; however, the results of serologic testing for rheumatoid factor were negative in both patients. Intraoperative findings and pathologic examination revealed degenerative fibrocartilage without inflammation or neoplasia. Similar lesions reported in the literature have been described as retro-odontoid disk hernia, damaged transverse ligaments, transverse ligament degeneration, synovial cysts, ganglion cysts, and degenerative articular cysts. These lesions may share a common pathophysiologic origin and represent a single disease process, namely exuberant degeneration of the transverse ligament.