Routine frontal Lumbar spine images are typically performed with the patient in which position?

• A. Supine on the table with knees flexed
• B. Prone
• C. Upright standing
• D. Lateral decubitus

Answer: (A)

For routine frontal views of the lumbar spine, placing the patient on their back with the knees flexed flattens the natural lumbar curve and stabilizes the spine against the image receptor. This reduces the angle of lordosis, minimizes magnification and distortion, and helps separate overlapping structures so the vertebral bodies and interspaces are seen more clearly. The knee flexion also relaxes the supporting muscles and reduces anterior tilt of the pelvis, keeping the lumbar region in a more neutral alignment that’s consistent across patients and easier to compare with prior studies.

Standing upright would increase the lumbar curve and magnification, making details harder to evaluate. A prone position changes the projection and isn’t used for the standard AP frontal lumbar view. A lateral decubitus is a distinct projection aimed at different information (a lateral view rather than an AP frontal view) and isn’t used for routine frontal imaging of the lumbar spine.