What it is (overview)

An XR Lumbar Spine Anteroposterior (AP) and Lateral exam is a standard lumbar X-ray (also called a spine X-ray) that takes two basic views of your lower back (lumbar spine). The AP view is taken from front to back, and the lateral view is taken from the side. Together, these images let a radiologist and your clinician evaluate the alignment and structure of the bones in your lower spine.

This test primarily shows bony anatomy, including the lumbar vertebrae, parts of the pelvis/sacrum that may be visible, and the spacing between vertebrae (an indirect clue about disc height). It can help detect or suggest issues such as fractures, arthritis-related changes, abnormal curvature, or vertebrae that have shifted out of place.

What the results mean in plain language: A “normal” result generally means the vertebrae look intact, the spine alignment is appropriate, and there are no clear signs of a fracture or major degenerative change on X-ray. If the report notes findings like degenerative changes, that often refers to “wear-and-tear” arthritis (such as bone spurs). If it notes loss of disc height, that suggests disc degeneration, though the discs themselves are not directly seen on X-ray. If it mentions compression fracture, spondylolisthesis (a slip of one vertebra over another), or scoliosis, those can help explain back pain and guide next steps. Because X-rays do not show nerves and soft tissues well, your clinician may recommend additional imaging (such as MRI or CT) if symptoms suggest a disc herniation, spinal stenosis, infection, or tumor.

When & why it's usually done

A lumbar spine AP and lateral X-ray is commonly ordered to evaluate lower back pain, especially when there is concern for a bone or alignment problem. It may be used after an injury, to check for fractures, or when symptoms persist and your clinician wants a clear look at the bony spine.

Your clinician may order this lumbar X-ray/spine X-ray if you have:

Symptoms or situations such as: ongoing or severe low back pain, pain after a fall or car accident, tenderness over the spine, new or worsening spinal deformity, difficulty standing fully upright due to pain, or pain that may be related to posture and alignment.

“Red flag” risk factors where checking the bones is especially important include: older age, osteoporosis or long-term steroid use (higher fracture risk), known cancer history (to assess for concerning bone changes), fever or unexplained weight loss (may prompt broader evaluation), or significant trauma.

The test is also used to help assess and monitor known conditions (for example, arthritis of the spine or spondylolisthesis) and to guide treatment decisions such as physical therapy, activity changes, medications, or whether more advanced imaging is needed.

Common diseases related to it

• Degenerative disc disease (disc space narrowing seen indirectly on X-ray)
• Osteoarthritis of the spine (lumbar spondylosis, bone spurs/osteophytes)
• Compression fracture (often related to osteoporosis)
• Traumatic lumbar spine fracture
• Spondylolisthesis (vertebral slippage)
• Spondylolysis (stress fracture/defect, sometimes suggested on X-ray)
• Scoliosis or abnormal spinal curvature
• Spinal alignment abnormalities (lordosis changes)
• Ankylosing spondylitis and other inflammatory spondyloarthropathies (may show characteristic changes in later stages)

Health goals where it may help

• Identifying the cause of persistent lower back pain and guiding a safe treatment plan
• Evaluating for fractures after a fall, sports injury, or car accident
• Monitoring progression of spinal arthritis/degenerative changes over time
• Assessing posture and spinal alignment issues that may affect mobility and daily function
• Supporting osteoporosis-related care by detecting or confirming vertebral compression fractures
• Determining when advanced imaging (MRI/CT) may be needed to investigate nerves, discs, or other soft tissues