How do I order upright radiographs of the lumbar spine, including anteroposterior (AP) and lateral views, as well as flexion and extension radiographs?

How to Order Upright Radiographs of the Lumbar Spine

To properly order lumbar spine radiographs, request upright anteroposterior (AP) and lateral views as standard, with flexion and extension views included when evaluating for potential instability. 1

Standard Views Required

• Upright radiographs should include anteroposterior (AP) and lateral views as the minimum standard requirement 1
• Upright positioning provides crucial functional information about axial loading of the spine 1
• The lateral view should visualize the entire lumbar spine, including the lumbosacral junction 1

When to Include Flexion and Extension Views

• Flexion and extension views should be included when evaluating for:
  • Suspected segmental instability 1
  • Spondylolisthesis assessment 1, 2
  • Post-surgical evaluation of fusion integrity 1
  • Evaluation of persistent symptoms after conservative management 1

Clinical Value of Different Views

• Upright AP and lateral views provide baseline assessment of alignment, disc height, and bony abnormalities 1
• Flexion and extension views specifically evaluate dynamic stability of the lumbar spine 2
• These dynamic views can reveal abnormal motion/increased mobility not apparent on static images 1

Limitations and Considerations

• Flexion-extension views may have limited value in acute settings due to muscle spasm and pain limiting motion 3, 4
• Some studies suggest that flexion-extension views rarely alter clinical management beyond what is seen on standard AP and lateral views 4
• Patient cooperation is essential for obtaining diagnostic quality dynamic views 2
• In some cases, sidebending views may provide complementary information but are not routinely needed 2

Alternative Positioning Techniques

• Some research suggests a "supine-prone" technique may be useful for evaluating low-grade spondylolisthesis 5
• However, standard upright flexion-extension views remain the most widely accepted method for assessing lumbar instability 2, 6

When Additional Imaging May Be Needed

• If radiographs reveal abnormalities or are inconclusive, advanced imaging may be warranted:
  • MRI lumbar spine without contrast is preferred for soft tissue evaluation 1
  • CT lumbar spine without contrast may be better for detailed bony assessment 1
  • CT myelography may be considered when MRI is contraindicated or inconclusive 1

Remember that while radiographs are often the initial imaging study, they have limitations in detecting early disc disease, soft tissue pathology, and subtle fractures 1.