Osteoarthrosis of the atlanto-axial joints. Long-term follow-up after treatment with arthrodesis.

We evaluated the results for fifteen patients in whom symptomatic osteoarthrosis of the atlanto-axial joints had been treated with an atlanto-axial or occipitocervical arthrodesis between 1973 and 1990. Thirteen patients had long-term follow-up (average duration, seven years and two months; range, four years and two months to nineteen years and two months). The two remaining patients had died: one, four days postoperatively, from a cardiopulmonary arrest, and the other, one year and eight months postoperatively, from complications related to bladder cancer. Preoperatively, all fifteen patients reported pain in the occipitocervical region that increased with any attempt at rotation of the neck and was unresponsive to immobilization with a collar and to analgesics. The average duration of the symptoms before the arthrodesis was three years. One patient had acute quadriparesis. All patients had radiographic evidence of oesteoarthrosis involving the lateral atlanto-axial articulations. Four patients had atlanto-axial instability with an average of five millimeters (range, three to ten millimeters) of motion at the anterior atlanto-odontoid interval. Six patients had an associated spontaneous subaxial fusion, which was secondary to osteoarthrosis in five; three of the five also had atlanto-axial instability. Fourteen patients were managed with a posterior arthrodesis and one, with an anterior transoral arthrodesis. The procedures were performed to relieve pain, to stabilize the atlanto-axial joints, and to restore neurological function. Of the fourteen patients who were followed, thirteen had a solid fusion and one had a stable pseudarthrosis. The patient who had quadriparesis recovered. At the latest follow-up evaluation, thirteen patients had an excellent result and one had a fair result as determined with use of a modification of the criteria of Robinson et al. There were no poor results. Atlanto-axial arthrodesis can effectively relieve occipitocervical pain and correct atlanto-axial instability secondary to osteoarthrosis.