What imaging modalities are used to diagnose spinal abnormalities?

From the Guidelines

Imaging for spinal abnormalities should begin with MRI, as it is the modality of choice for assessing the spinal cord and nerve roots, and provides excellent visualization of soft tissues, including discs, nerves, and the spinal cord, without radiation exposure. This approach is supported by the most recent and highest quality study, which emphasizes the importance of MRI in evaluating spinal cord pathologies, such as transverse myelitis, infections, demyelinating diseases, neoplasm, vascular malformations, spondylosis, and neurodegenerative disorders 1.

When considering the diagnosis of spinal abnormalities, the following imaging modalities may be used:

• MRI: for assessing soft tissues, including discs, nerves, and the spinal cord
• CT scans: for evaluating bony structures, and may be used when MRI is contraindicated or unavailable
• CT myelography: for assessing the patency of the spinal canal/thecal sac and of the subarticular recesses and neural foramen, and has safety advantages over MRI for patients with implanted medical devices that are not MRI safe or conditional
• Radiography: for evaluating alignment and hardware integrity in patients with previous lumbar fusion, and provides useful functional information about axial loading

It is essential to note that imaging should be correlated with clinical findings, as abnormalities like disc bulges and degenerative changes are common in asymptomatic individuals and may not explain the patient's pain 1.

In specific scenarios, such as suspected spine infection, MRI without and with IV contrast is the preferred imaging modality, as it provides excellent tissue characterization and anatomic delineation, with a sensitivity of 96% and a specificity of 94% for the evaluation of patients with suspected spine infection 1.

Overall, the choice of imaging modality depends on the specific clinical scenario and the patient's individual needs, and should always prioritize the patient's morbidity, mortality, and quality of life as the outcome.

From the Research

Imaging Modalities for Diagnosing Spinal Abnormalities

The following imaging modalities are used to diagnose spinal abnormalities:

• Multidetector CT: recommended when there is concern for fracture of the lumbar spine 2
• MRI: recommended for patients with severe or progressive neurologic deficit on presentation and red flags, and for those deemed to be interventional candidates with LBP lasting for > 6 weeks having completed conservative management with persistent radiculopathic symptoms 2, 3
• Plain radiographs: may be used to evaluate lumbar spine imaging requests, with 76.7% of requests being judged as appropriate 4
• Computed tomography: may be used to evaluate lumbar spine imaging requests, with 86.4% of requests being judged as appropriate 4
• DEXA scans: considered the gold standard test for the assessment of bone density, but MRI may also be used to assess bone density and detect osteoporosis 5

Indications for Imaging

Imaging is considered in the following situations:

• Patients who have had up to 6 weeks of medical management and physical therapy that resulted in little or no improvement in their back pain 2, 3
• Patients presenting with red flags raising suspicion for serious underlying conditions, such as cauda equina syndrome, malignancy, fracture, and infection 2, 3
• Patients with severe or progressive neurologic deficits on presentation 2, 3
• Patients with suspected vertebral fracture or malignancy 4