Transverse ligament rupture and atlanto-axial subluxation in children.

We report four children aged two to nine years with traumatic tears of the transverse ligament of the atlas and atlanto-axial subluxation. This is extremely rare in this age group since trauma usually causes a skeletal rather than a ligamentous injury. The injuries resulted from falls or motor vehicle accidents, with considerable delay in diagnosis. Flexion radiographs showed atlas-dens intervals (ADI) of 6, 7, 8 and 13 mm; all four patients were treated by posterior fusion at C1-C2 after the failure of conservative treatment. In one child with quadriparesis and a fixed ADI of 13 mm, transoral anterior resection of the odontoid was performed before the fusion. Diagnosis of this traumatic lesion requires a high level of suspicion. Conservative treatment is likely to fail; surgical stabilisation is indicated.