Lumbar Spine
The primary goal of the Lumbar Spine series is to demonstrate the entire lumbar spine (L1 through L5, including the L5-S1 junction), allowing for the evaluation of:
Pathology, such as fractures, dislocations, degenerative disc disease, and lumbosacral junction intricacies.
Vertebral body alignment and bone density.
The integrity of the intervertebral disc spaces and joint spaces.
Lumbar Spine (L-Spine) Imaging
Quick Reference: Lumbar Spine Positioning
AP Lumbar Spine
Positioning
- Patient supine with MSP centered to the IR.
- The Knee Flex: Flex knees and hips to reduce lumbar lordosis and open intervertebral joint spaces.
Central Ray
- Perpendicular to IR, centered to the level of the Iliac Crests (L4).
Quality Check
- T12 through sacrum visible. No rotation (symmetric SI joints).
Lateral Lumbar Spine
Positioning
- True lateral position with knees flexed for stability.
- Ensure long axis of spine is parallel to IR (use sponges if needed).
Central Ray
- Perpendicular to IR, centered to the level of the Iliac Crests at the mid-coronal plane.
Quality Check
- Vertebral bodies in profile; intervertebral disk spaces open.
Oblique Lumbar Spine (RPO/LPO)
Positioning
- Body rotated 45 degrees toward the IR.
- Support patient with sponges to maintain consistent angle.
Central Ray
- Perpendicular to IR, centered 1.5″ superior to iliac crest and 2″ medial to upside ASIS.
Quality Check
- Clear “Scottie Dog” silhouette; zygapophyseal joints closest to IR should be open.
L5-S1 Lumbar Spot
Positioning
- True lateral position; tight collimation is vital to improve junction detail.
Central Ray
- Angle 5° to 8° Caudal centered 1.5″ inferior to iliac crest and 2″ posterior to ASIS.
Quality Check
- L5-S1 joint space clearly open and centered in the field.