Occipital condyle fractures: clinical presentation and imaging findings in 76 patients.

The aim was to assess the frequency and type of occipital condyle fractures in patients with significant trauma, and determine the frequency in which conventional radiographic findings are positive. Secondarily, we subjectively evaluate the application of existing classification systems. Fracture of the occipital condyle is an uncommon lesion that may be associated with craniocervical instability. Relying on conventional radiographs to detect these injuries may be inappropriate. An institutional trauma database of patients was searched for patients with occipital condyle fractures. The types of fractures were classified retrospectively based on re-review of imaging studies, using existing classification systems. Frequency of types was calculated, and the ease of use of the fracture classifications was evaluated subjectively. Conventional radiographs were reviewed for the presence of subjective soft tissue swelling and the visibility of the fracture(s). Seventy-six patients had CT images available for re-review. None of the occipital condyle fractures could be identified in the 60 patients who had radiographs available for re-review. Because of the presence of life support tubing and pharyngeal fluid limiting evaluation of prevertebral soft tissue swelling, the presence of widened prevertebral soft tissues was only helpful in 7 of the 60 patients. The multiplanar reformatted CT images were useful to determine alignment at C0-C1 and C1-C2. Occipital condyle fractures were not visualized on conventional radiographs. Secondary findings of soft tissue swelling were often absent or unreliable. CT scanning with multiplanar reconstruction imaging plays an indispensable role in evaluating for fractures of the cervical spine, and for determining alignment at C0-C1-C2. The most recently developed classification system of Tuli et al. (Neurosurgery 41: 368-376, 1997) is useful, but suffers from the lack of a defined distinction between undisplaced (Type I, stable) and displaced (Type 2A, unstable) fracture fragments.