Film Critique of the Lumbar Spine, Sacrum and Coccyx
AP Lumbar Spine
 Vertebral bodies of T12-L5 should be included
 The iliac crests and SI joints should be symmetrical
 Spinous processes should be visualized in the middle of the vertebral bodies
 Intervertebral disk spaces should be clearly demonstrated
AP Oblique Lumbar Spine
 Vertebral bodies of T12-L5 should be included
 When RPO and LPO positions are compared, the ilia should be symmetrical
 The right zygapophyseal joints should be visible in the RPO position
 The left zygapophyseal joints should be visible in the LPO position
 Pedicles should be demonstrated in the middle of the vertebral body
 If pedicle is anterior to vertebral body, there is too much rotation
 If pedicle is posterior to vertebral body, there is not enough rotation
 “Scotty Dog” should be visualized
Lateral Lumbar Spine
 Vertebral bodies of T12-S1 should be included
 L1-L5 should be adequately penetrated
 Intervertebral disk spaces should be clearly demonstrated
 *Note: exposure on expiration will free L1 from superimposition of the lungs
Lateral “Spot” for L5-S1
 The entire vertebral bodies of L5 and S1 should be included
 Intervertebral disk space between L5 and S1 should be well demonstrated
 *Note: tube angulation may vary depending on body habitus
 If hips are larger than upper abdomen, angle caudal
 If hips are smaller than upper abdomen, angle cephalic
AP Sacrum
 The L5-S1 disk space and symphysis pubis should be included on the film
 The alea of the sacrum should be symmetrical
 Angle tube perpendicular to sacrum (approximately 15 degrees cephalic)
AP Coccyx
 The coccyx and approximately 1/3 of the sacrum should be included
 kV should be adjusted to produce a high-contrast image
 The coccyx should appear directly above the symphysis pubis
Lateral Sacrum/Coccyx
 The L5-S1 disk space and the entire sacrum and coccyx should be included on the film
 The femoral heads should be superimposed
 The sacrum should be clearly visible without overexposure of coccyx (take additional
film if needed)