Craniovertebral instability due to degenerative osteoarthritis of the atlantoaxial joints: analysis of the management of 108 cases Clinical article

Object. The authors retrospectively analyzed a series of 108 patients in whom was diagnosed atlantoaxial instability clue to degenerative osteoarthritis of the atlantoaxial joints. The management issues in such cases are discussed. Methods. One hundred eight patients with osteoarthritis of the atlantoaxial joints and resultant craniovertebral instability diagnosed on the basis of presenting clinical features, radiological imaging, and direct observation of the joint status during surgery were retrospectively analyzed. Between 1990 and 2008, these patients were treated with a C1-2 lateral mass plate and screw method of atlantoaxial fixation and joint distraction using bone graft with or without the assistance of metal spacers. Results. Patient ages ranged from 48 to 84 years (average 63 years). There was a history of mild to moderate head and/or neck trauma 2 months to 11 years prior to diagnosis in 40% of the cases. All patients had symptoms of neck pain, and 82% of the patients had progressive myelopathy. A reduction in the height of the atlantoaxial lateral mass complex (100%), mobile atlantoaxial dislocation (100%), basilar invagination (68%), and periodontoid degenerative tissue mass (90%) were the more frequently encountered radiological features. Two patients died in the immediate postoperative period. At an average follow-up of 64 months, all surviving patients remarkably improved to varying degrees in their neurological condition. Conclusions. Atlantoaxial joint arthritis frequently leads to craniovertebral instability and cord compression. Treatment by joint distraction and lateral mass fixation can be an optimum form of treatment. (DOI: 10.3171/2009.12.SPINE0999)