What's the next step in managing a patient with tingling, numbness, and limited lateral rotation after a motor vehicle accident, with a normal cervical spine X-ray?

Next Step: Obtain Urgent MRI of the Cervical Spine

This patient requires urgent MRI evaluation of the cervical spine to rule out ligamentous injury, spinal cord contusion, or central cord syndrome, despite the normal X-ray. The presence of neurological deficits (tingling, numbness, limited lateral rotation) following trauma mandates advanced imaging regardless of normal plain films 1, 2.

Clinical Reasoning

Why MRI is Essential in This Case

• Plain X-rays miss up to 77% of cervical spine abnormalities in patients with suspected injury, while MRI detects 79% 1
• Any patient with neurological deficit referable to the cervical spine should undergo MRI, as this is the gold standard for evaluating spinal cord injuries and has replaced CT myelography 1
• Up to 25% of cervical spine injuries have no associated fracture and will not appear on plain films or CT, yet may represent unstable ligamentous injuries that can progress to catastrophic cord injury if the patient is mobilized 1
• The American College of Radiology specifically recommends imaging for patients with paresthesias in extremities regardless of other factors 2

What MRI Will Detect That X-ray Cannot

• Ligamentous injuries: MRI reveals ligamentous injury in approximately 20-25% of cases not visible on plain films 1
• Spinal cord contusion or compression: MRI is the only modality that can directly visualize cord injury 1, 3
• Epidural hematoma: Over 13% of post-traumatic epidural hematomas have normal CT scans and are only diagnosed on MRI 1
• Disc herniation: 36% of cervical spinal cord injuries have associated disc herniation or protrusion visible only on MRI 1

Immediate Management Algorithm

Step 1: Maintain Spinal Precautions

• Continue cervical spine immobilization until MRI is completed and reviewed 2, 3
• Manual stabilization of the head to minimize motion of head, neck, and spine 3

Step 2: Obtain Urgent MRI

• Perform MRI without delay if it can be done safely without endangering the patient 1
• MRI should be obtained preoperatively to guide potential surgical intervention 1

Step 3: Consider Surgical Timing

• If MRI reveals cord compression or unstable injury, surgical decompression should occur within 24 hours to improve long-term neurological recovery 1, 3

Critical Pitfalls to Avoid

Do Not Clear the Spine Based on Normal X-ray Alone

• A normal cervical spine X-ray does NOT exclude significant injury in a patient with neurological symptoms 1
• Delayed diagnosis of cervical spine injury produces 10 times higher rates of secondary neurological injury (10.5% vs. 1.4%) 1
• 29.4% of cases with delayed diagnosis develop permanent neurological deficits 1

Do Not Delay MRI for Non-Critical Reasons

• The expected benefits of MRI outweigh risks when performed under safe conditions 1
• Early MRI-based protocols have been associated with better functional recovery and shorter ICU stays in cervical injuries 1

Recognize Potential Central Cord Syndrome

• This patient's presentation (numbness, limited rotation after hyperextension mechanism) could represent central cord syndrome, which requires urgent MRI and potential early decompression within 24 hours 3
• Central cord syndrome can occur with or without fracture and is characterized by disproportionate upper extremity involvement 3

Additional Considerations

• If MRI is contraindicated or unavailable, CT with high-resolution imaging (1.5-2 mm collimation) is the next best option, though it will miss purely ligamentous injuries 1
• Prolonged immobilization beyond 48-72 hours carries significant morbidity including pressure sores, increased intracranial pressure, and aspiration risk 1
• Transfer to a specialized spinal cord injury center should be arranged if MRI reveals significant pathology 3