What evaluation should be done for a patient after a cervical spine injury?

Comprehensive Evaluation Protocol for Cervical Spine Injury

For patients with suspected cervical spine injury, a multimodal imaging approach is required, with CT scan as the primary initial imaging modality, followed by MRI when neurological deficits are present or ligamentous injury is suspected. 1, 2

Initial Assessment and Risk Stratification

• Patients should be evaluated using validated clinical criteria such as NEXUS or Canadian Cervical Rules (CCR) to determine the need for imaging 1
• Imaging is indicated for patients with any of the following NEXUS criteria: midline cervical tenderness, focal neurologic deficit, altered level of consciousness, intoxication, or distracting injury 2
• Patients ≥65 years old should undergo imaging regardless of clinical presentation due to decreased sensitivity of NEXUS criteria in this population (66-89%) 1
• All patients with neurological symptoms referable to the spine require immediate imaging evaluation 2

Imaging Protocol

For Alert, Evaluable Patients:

• CT scan of the cervical spine is the preferred initial imaging modality, having replaced plain radiographs due to significantly higher sensitivity for detecting fractures 1
• CT scanning detects more fractures while plain films better detect malalignment; the combination of both modalities is complementary but CT is primary 1
• Pay special attention to the craniocervical and cervicothoracic junctions, which frequently conceal injuries and are poorly visualized on plain films 1

For Unconscious or Obtunded Patients:

• CT scan of the entire cervical spine is mandatory as the initial imaging study 1, 2
• Entire cervical spine CT detects significantly more injuries than plain films or directed CT scanning with a number needed to treat of 2 for all injuries and 8-22 per unstable injury 1
• CT scanning time is actually less than that required for a full plain film evaluation (12 minutes if added to a head scan) 1

MRI Indications and Benefits

• MRI is the investigation of choice for evaluating spinal cord injuries and has replaced conventional and CT myelography 1
• MRI should be performed urgently in any patient with neurological deficits referable to the cervical spine 2
• MRI can detect ligamentous injuries that have no associated fracture and may not appear on plain films or CT 1
• Following polytrauma, MRI may reveal unsuspected soft tissue injury in approximately 25% of cases 1
• MRI is particularly important for detecting isolated cervical spine injuries without fractures that could lead to instability if missed 1

Special Considerations

• Prolonged immobilization has significant attributable morbidity (pressure sores, increased intracranial pressure, airway problems) with complications escalating after 48-72 hours 1
• For unconscious polytrauma victims, management should consider whether they will be clinically evaluable within 48-72 hours 2
• The combination of a plain film series and directed CT may exclude >99% of injuries, but entire CT scanning further reduces the incidence of false negatives 1
• In patients with cervical spine injury, always evaluate for injuries at other levels of the spine, as approximately 20% of patients have noncontiguous spinal injuries 1

Common Pitfalls to Avoid

• Suboptimal and anatomically incomplete imaging combined with misinterpretation account for the largest number of missed injuries 1
• Relying solely on plain radiographs is inadequate; the most common reason for missed cervical spine injuries is technically inadequate radiographic series 3
• Attempting to clear the cervical spine in patients with distracting injuries or intoxication should be avoided as these may mask symptoms 2
• SCIWORA syndrome (spinal cord injury without radiographic abnormality) is common in children and requires MRI for diagnosis 3
• Hidden discoligamentous injuries may not be evident on initial imaging and require thorough clinical and radiographic follow-up 4