Atlanto-axial tuberculosis in adults.

Twelve adult patients with confirmed tuberculosis of the atlanto-axial spine are presented and a classification proposed. Stage I has minimal ligamentous or bone destruction and no displacement of C1 on C2; the suggested treatment is transoral biopsy and decompression followed by an orthosis. Stage II has ligamentous disruption and minimal bone destruction but anterior displacement of C1 on C2; treatment involves transoral biopsy and decompression, reduction by halo traction, then a posterior C1-2 fusion. Stage III has marked ligamentous and bone destruction with displacement of C1 forward on C2; the suggested treatment is transoral biopsy and decompression, reduction by halo traction, then fusion from the occiput to C2 or C3. One patient died before treatment started; all the others have gone on to solid union with resolution of any neurological deficit. There has been no evidence of reactivation of disease over an average follow-up of 36 months.