Magnetic resonance imaging evaluation of the cervical spine in the comatose or obtunded trauma patient

Abstract

Object. Confirmation of cervical spine stability is difficult to obtain in the comatose or obtunded trauma patient. Concurrent therapies such as endotracheal intubation and the application of rigid cervical collars diminish the utility of plain radiographs. Bony as well as supportive soft-tissue structures must be evaluated before the cervical spine can be determined to be uninjured. Although major injuries to extradural soft-tissue structures in the awake trauma patient are frequently excluded by physical examination, when the patient is obtunded the physical examination may be unreliable. Therefore, an enhanced diagnostic method for the evaluation of soft-tissue injury is desirable. The authors conducted a study in which magnetic resonance (MR) imaging was used as such a method to assess posttraumatic spinal stability in the comatose or obtunded patient. Methods. Early, limited (sagittal T1- and T2-weighted) MR imaging was performed posttruama in 121 patients to assess soft-tissue injury. In all patients the mechanism of injury potentially could be associated with cervical spine instability, and each patient was endotracheally intubated because of head injury or severe multisystem injuries. All patients underwent imaging studies within 48 hours of injury and were either treated or cleared and spinal precautions were discontinued. Patients were excluded from this study if they had an obvious cervical spine injury identified on the initial radiographic studies or if they were determined to be too medically unstable to undergo MR imaging within the acute period (<48 hours postinjury). Thirty-one (25.6%) of the 121 patients were found to have sustained significant injury to the paravertebral ligamentous structures, the disc interspace, or the bony cervical spine. These injuries were undetected by plain radiography. The other 90 patients (74.4%) were determined within 48 hours not to have sustained a soft-tissue injury. Eight patients (6.6%) ultimately underwent surgery to treat the cervical spine injury, and MR imaging was the first test that identified the injury in each of these patients. There were no complications related to imaging procedures. Conclusions. Sagittal T1- and T2-weighted MR imaging appears to be a safe, reliable method for evaluating the cervical spine for nonapparent injury in comatose or obtunded trauma patients. In the early postinjury period, nursing and medical care are thereby facilitated for patients in whom occult injury to the spine is ruled out and for whom those attendant precautions are unnecessary.