CT is the preferred cervical spine screening modality in trauma patients at high and moderate risk for cervical spine fracture.

Object Craniocervical dissociation (CCD) is a highly unstable and usually fatal injury resulting from osseoligamentous disruption between the occiput and C-2. The purpose of this study was to elucidate systematic factors associated with delays in diagnosing and treating this life-threatening condition and to introduce an injury-severity classification with therapeutic implications. Methods In a retrospective evaluation of institutional databases, the authors reviewed medical records and original images obtained in 17 consecutive surviving patients with CCD treated between 1994 and 2002. Images and clinical results of treatment were evaluated, emphasizing the timing of diagnosis, clinical effect of delayed diagnosis, potential clinical or imaging warning signs, and response to treatment. Craniocervical dissociation was identified or suspected on the initial lateral cervical spine radiograph acquired in two patients (12%) and was diagnosed based on screening computerized tomography findings in two additional patients (12%). A retrospective review of initial lateral x-ray films showed an abnormal dens–basion interval in 16 patients (94%). The 2-day average delay in diagnosis was associated with profound neurological deterioration in five patients (29%). Neurological status declined in one patient after a fixation procedure was performed. There were no cases of craniocervical pseudarthrosis or hardware failure during a mean 26-month follow-up period. The mean American Spinal Injury Association (ASIA) motor score of 50 improved to 79, and the number of patients with useful motor function (ASIA Grade D or E) increased from seven (41%) preoperatively to 13 (76%) postoperatively. Conclusions The diagnosis of CCD was frequently delayed, and the delay was associated with an increased likelihood of neurological deterioration. Early diagnosis and spinal stabilization protected against worsening spinal cord injury.

Lumbopelvic fixation in spinal and pelvic surgery relies on rods or screws as an iliac anchor. Secure placement of screws with maximum diameter and length for the greatest pullout strength requires knowledge of the iliac structure and of intraoperative fluoroscopic landmarks for secure placement. Therefore, the authors evaluated the intrailiac length, inner width, and cortical thickness of three different transiliac screw anchor paths aimed toward the anterior inferior iliac spine and initiated at the iliac tubercle, posterior superior iliac spine, or posterior inferior iliac spine. Measurements were made using two- and three-dimensional computed tomographic reformations in 40 consecutive trauma patients (27 measurements in 21 males, 16 to 75 years old; 28 measurements in 19 females, 16 to 78 years old). In addition, fresh and dry human cadaveric specimens were marked with metal wires at the previously determined optimal screw path to determine fluoroscopic landmarks for easiest and best controlled transiliac screw placement. The posterior superior iliac spine-anterior inferior iliac spine path had the largest bony canal lengths, with 141 mm in male and 129 mm in female patients. Two stereotypic iliac constrictions allowed placement of 8-mm implants in male and 6- to 7-mm implants in female patients. Cortical thickness at that optimal extraarticular path was 5.2 mm in the male and 4.7 mm in the female patients. Transiliac screws can be placed during operation under fluoroscopic control using standard lateral and obturator oblique-outlet views, the latter presenting a stereotypical teardrop figure above the acetabulum.