Closed head injury in acute traumatic spinal cord injury: incidence and risk factors.

Investigators estimate that 15% to 50% of all patients with spinal cord injury (SCI) also incur a closed head injury (CHI), but studies have been hampered by design flaws, including retrospective assessment and inconsistent definition of CHI. We conducted a prospective study of combined CHI and SCI among 82 SCI patients consecutively admitted at two hospitals within 24 hours of injury. The purpose of the study was to determine the incidence and duration of loss of consciousness and posttraumatic amnesia (PTA), and to establish the risk factors for combined CHI and SCI. The overall incidence of CHI as defined by the presence of PTA of any duration was 49%. There was a significantly increased risk of CHI for patients involved in traffic accidents (risk ratio = 3.7; 95% confidence interval 1.8 to 7.2). There was no increased risk associated with level of injury (quadriplegic vs paraplegic; risk ratio = 1.2; 95% confidence interval = 0.8 to 1.8). All SCI patients, regardless of level of injury, deserve systematic evaluations for CHI in their acute care evaluations.