When labeling the vertebral bodies on a PA lumbar scan, which vertebrae should you start labeling from?

• A. L1
• B. L2
• C. L3
• D. L4

Answer: (D)

In a PA (posteroanterior) lumbar spine scan, the appropriate sequence for labeling the vertebral bodies typically begins with L1. This is because L1 is the first lumbar vertebra located at the uppermost dorsal aspect of the lumbar region.

Labeling from L1 ensures a systematic and consistent approach, as this vertebra serves as a reference point for the subsequent labeling of L2, L3, L4, and so on. Starting from L1 also aligns with the anatomical position, making it easier for clinicians and radiologists to communicate findings efficiently.

Labeling L4 first would create confusion, as it is positioned lower in the spine than L1, and would not maintain the established anatomical order that clinicians rely on when interpreting scans. Always starting from the uppermost vertebra and working downward maintains clarity and precision in documentation and analysis.