OCCIPITAL CONDYLE FRACTURE AND LIGAMENT INJURY - IMAGING BY CT

The true incidence of fracture of the occipital condyles is unknown. I t may be associated with instability at the craniocervical joint. CT i s the modality of choice for the demonstration of these fractures, but its use for imaging of the associated ligament injury has not been re ported. In order to demonstrate normal anatomy, occipital condyle frac ture and ligament injury, and to estimate the incidence of this lesion , 21 children and young adults with high-energy blunt craniocervical i njury were examined prospectively. Thin-slice, axial, contiguous, CT w as performed from the base of C2 to above the foramen magnum. Bone and soft tissue windows and coronal, sagittal, and curvilinear 2D reconst ructions were performed. Five occipital condyle fractures were identif ied in four patients (19 %), with demonstration of alar ligament injur y in two cases and local hematoma in one. In four, artifacts or rotati on precluded assessment of ligaments, In all remaining cases normal bo ne and ligament anatomy was demonstrated. Fracture of the occipital co ndyles following craniocervical injury is not uncommon in children and young adults. Normal bone and ligament anatomy and pathology can be s afely and clearly demonstrated in seriously injured patients and other s using this CT technique. Increased awareness of this entity and a lo w threshold for performing CT should avoid the potentially serious con sequences of a missed diagnosis.