INTRODUCTION: The early recognition of cervical spine injury remains a top priority of acute trauma care. Missed diagnoses can lead to exacerbation of an existing injury and potentially devastating consequences. We sought to identify predictors of cervical spine injury. METHODS: Trauma registry records for blunt trauma patients cared for at a Level I Trauma Centre from 1997 to 2002 were examined. Cervical spine injury included all cervical dislocations, fractures, fractures with spinal cord injury, and isolated spinal cord injuries. Univariate and adjusted odds ratios (ORs) were calculated to identify potential risk factors. Variables and two-way interaction terms were subjected to multivariate analysis using backward conditional stepwise logistic regression. RESULTS: Data from 18,644 patients, with 55,609 injuries, were examined. A total of 1255 individuals (6.7%) had cervical spine injuries. Motor Vehicle Collision (MVC) (odds ratio (OR) of 1.61 (1.26, 2.06)), fall (OR of 2.14 (1.63, 2.79)), age <40 (OR of 1.75 (1.38-2.17)), pelvic fracture (OR of 9.18 (6.96, 12.11)), Injury Severity Score (ISS) >15 (OR of 7.55 (6.16-9.25)), were all significant individual predictors of cervical spine injury. Neither facial fracture nor head injury alone were associated with an increased risk of cervical spine injury. Significant interactions between pelvic fracture and fall and pelvic fracture and head injury were associated with a markedly increased risk of cervical spine (OR 19.6 (13.1, 28.8)) and (OR 27.2 (10.0-51.3)). CONCLUSIONS: MVC and falls were independently associated with cervical spine injury. Pelvic fracture and fall and pelvic fracture and head injury, had a greater than multiplicative interaction and high risk for cervical spine injury, warranting increased vigilance in the evaluation of patients with this combination of injuries.