Anterior stabilization for acute fractures and non-unions of the dens.

The dens can be reached and directly stabilized from an anterior cervical approach, provided that x-ray image intensification is employed. Through this approach, twelve delayed unions and non-unions of the dens were treated with a bone graft impacted into a trough in the body of the second cervical vertebra and into a canal in the dens, together with a concomitant posterior arthrodesis. Fifteen additional fractures of the dens were stabilized with compression screws, introduced from the anteroinferior margin of the second cervical vertebra into the dens. Four of these fractures had delayed union, and an anterior onlay bone graft was added to the screw fixation. All of the delayed unions, non-unions, and acute fractures healed with bone union and without major complications. The acute fractures showed bone union in six to eight weeks after anterior fixation with compression screws alone. Delayed unions were found to need an anterior onlay bone graft in addition to the screw fixation. Established non-unions should be stabilized with a posterior arthrodesis of the first to the second cervical vertebra and inlay grafting of the non union itself to ensure both anterior and posterior healing.