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.