Surgery of Atlantoaxial Osteoarthritis

Background: Unilateral atlantoaxial osteoarthritis (AAOA) is an underdiagnosed condition characterized by severe occipitocervical pain and restricted head rotation. This study aimed to compare clinical outcomes and complications associated with different surgical methods used to treat AAOA in cases where conservative management fails. Methods: This was a retrospective cohort study conducted at Tampere University Hospital, Finland, with patients treated between 2004 and 2024. Patients were divided into two groups based on the surgical approach. Clinical outcomes were evaluated at a median follow-up of 60 days postoperatively, with a focus on pain reduction and complication rates. The study included 49 patients diagnosed with unilateral AAOA who underwent either C1-2 fixation with or without second cervical vertebra (axis) (C2) nerve root decompression (group 1) or only C2 nerve root decompression (group 2). Results: Both groups showed substantial pain reduction with good or excellent outcomes in 82.3% in group 1 and 73.3% in group 2. Complications were more common in group 1 (29.4%) than in group 2 (13.3%), with sensory loss in the C2 dermatome being the most frequent complication. Conclusions: These findings suggest that both C1-2 fixation and C2 nerve root decompression are safe and effective methods for pain caused by AAOA, the latter especially when symptoms are related to C2 radiculopathy.