Which views are used to assess lumbar spine instability?

• A. Supine imaging
• B. Oblique views
• C. Flexion-extension views (lateral)
• D. AP view only

Answer: (C)

Dynamic assessment of the lumbar spine relies on seeing how the vertebrae move when the spine is stressed. Flexion-extension lateral views provide that stress by taking images in two positions: one with the spine flexed and one with it extended. By comparing these two positions, you can detect abnormal movement between vertebrae—such as translation (slippage) or unusual angulation—that indicates instability. Static images, like supine or AP/oblique views, don’t reveal how the segments move in flexion or extension, and they can miss instability that only shows up under load. Therefore, these lateral flexion-extension views are the best choice for evaluating lumbar instability, since they directly demonstrate the spine’s dynamic behavior.