From the Guidelines
Spinal imaging in the emergency department is indicated for patients with suspected spinal injuries or conditions requiring urgent intervention, including trauma, neurological deficits, suspected cauda equina syndrome, severe or progressive pain, and suspected spinal infections or malignancies. The primary indications for spinal imaging can be broken down into several key categories:
- Trauma with high-risk mechanisms, such as falls from height, motor vehicle accidents, or direct spinal impact 1
- Neurological deficits, including weakness, numbness, or bowel/bladder dysfunction 1
- Suspected cauda equina syndrome, which is a medical emergency requiring prompt imaging and intervention 1
- Severe or progressive pain unresponsive to conservative management, which may indicate underlying conditions such as spinal stenosis or disc herniation 1
- Suspected spinal infections or malignancies, which require urgent imaging and treatment to prevent serious complications 1
The choice of imaging modality depends on the clinical presentation and the suspected underlying condition.
- CT scans are typically the first-line imaging modality for trauma cases due to their speed and ability to detect fractures 1
- MRI is preferred for evaluating soft tissue structures, cord compression, and non-traumatic conditions, such as cauda equina syndrome or spinal stenosis 1
- Plain radiographs may be used for initial screening in low-risk cases but have limited sensitivity and are not recommended for patients with suspected serious underlying conditions 1
Patients with red flags, such as fever, unexplained weight loss, immunosuppression, or history of cancer, warrant more urgent imaging and evaluation to rule out underlying serious conditions 1.
- Early appropriate imaging can significantly impact patient outcomes by enabling timely interventions for conditions requiring surgical management or other specific treatments 1
- The most recent and highest quality study, published in 2021, recommends MRI lumbar spine without IV contrast as the initial imaging study of choice in the evaluation of suspected cauda equina syndrome, multifocal deficit, or progressive neurologic deficit 1
From the Research
Indications for Spinal Imaging in the Emergency Department
The following are indications for spinal imaging in the Emergency Department (ED):
- Lower back pain, particularly in patients with a history of trauma, neoplasm, or infection 2, 3, 4
- Trauma, even if relatively minor, especially in elderly patients 2
- Neurologic deficit, although this may not always correlate with abnormalities on lumbosacral radiographs 2
- History of intravenous drug use (IVDU), as these patients are at higher risk of spinal infection 5
- Suspicion or history of cancer, as this increases the likelihood of spinal cancer 4
- Presence of red flags, such as:
- Suspicion or history of cancer
- Intravenous drug use
- Indwelling vascular catheter
- Other infection site
- Recent trauma
- Progressive neurologic deficits
Imaging Modalities
The choice of imaging modality depends on the clinical presentation and suspected underlying condition:
- Radiography is commonly used for initial evaluation of low back pain, but may not provide clinically useful information in patients with isolated lower back pain 2, 6
- CT and MRI may be used in patients with suspected serious underlying conditions, such as spinal infection or cancer 5, 6
- MRI is the exam of choice for suspected spinal infection, particularly in patients with a history of IVDU 5
Prevalence of Serious Spinal Pathologies
The prevalence of serious spinal pathologies in patients presenting to the ED with low back pain is estimated to be:
- 2.5%-5.1% in prospective studies
- 0.7%-7.4% in retrospective studies
- Specific pathologies include:
- Vertebral fractures: 0.0%-7.2%
- Spinal cancer: 0.0%-2.1%
- Infectious disorders: 0.0%-1.9%
- Pathologies with spinal cord/cauda equina compression: 0.1%-1.9%
- Vascular pathologies: 0.0%-0.9% 4