Trauma in congenital atlanto-axial dislocation

Congenital atlanto-axial dislocation (AAD) usually presents with chronically progressive compression of the cervico-medullary junction. However, even a minor trauma can cause acute compression with development of quadruplegia and respiratory impairment. At times these may be transient, or trauma may aggravate the compression and lead to progressive quadriplegia. Of 60 children seen with congenital AAD, in 15 it had been associated with trauma. Nine of these 15 AADs were of the mobile variety, and 6 of the fixed variety with odontoid invagination. In 6 children with mobile and 2 with fixed AAD, trauma led to an acute manifestation with quadriplegia. Three of the children also experienced respiratory distress and needed ventilatory support. All 15 were initially treated with skull traction. Once the condition was stabilised, those with the mobile variety underwent fixation in a reduced position and grafting. One of the children with respiratory distress died within 2 days of admission. In 4 of them, sublaminar wiring between C1 and C2 was carried out, and in 3 others wiring between occiput and base of spinous process of C2 was performed. In 1 case a Hartshill loop was used. Among the children with fixed AAD, reduction of the odontoid invagination was obtained in 2, and they underwent fusion. In 4 cases with unsatisfactory reduction, posterior decompression of the foramen magnum and the fused posterior arch of the atlas was performed. The results depended on the degree of neurological deficit in each child.