X Ray Lumbosacral Spine Lateral Extension View

An X-ray of the lumbosacral (LS) spine in lateral flexion is a radiographic study taken while the patient bends sideways. Paired bending views evaluate lumbar and lumbosacral segment alignment and motion, helping detect abnormal translation or angulation (instability), spondylolisthesis, progressive degenerative change, or inadequate fusion. It’s a simple, low‑radiation test used to assess spinal stability and guide treatment planning.

The four standard lumbar spine radiographic views are: 1) Anteroposterior (AP) — overall alignment and vertebral bodies; 2) Lateral — disc spaces, vertebral height and spondylolisthesis; 3) Right oblique — visualizes right facet joints and pars interarticularis; 4) Left oblique — visualizes left facet joints and pars. Bilateral obliques help detect facet arthropathy or pars defects.

Place the patient in a true lateral (standing or lateral recumbent) with the side nearest the detector (usually left) against the receptor. Flex hips and knees, stack pelvis and shoulders, and raise arms out of the field. Center the beam perpendicular to the cassette at the L3–L4/L4 (iliac crest) level to include L1 through the sacrum. Suspend respiration.

LAT (lateral) view in an LS spine X‑ray is a side projection of the lumbosacral region. It shows sagittal alignment, vertebral body heights, intervertebral disc spaces, posterior elements and the L5–S1 junction, helping detect fractures, compression, spondylolisthesis, degenerative changes and abnormal lordosis. The image is obtained with the patient standing or in lateral decubitus and the beam directed mediolaterally.

A lateral view is an X‑ray taken from the side, with the X‑ray beam passing right‑to‑left or left‑to‑right through the body. It produces a side‑on image showing anterior‑posterior relationships, depth, and alignment of bones and soft tissues, helping localize lesions, detect chest fluid or collapse, and assess spine or joint positioning when frontal views are inconclusive.

Dynamic flexion and extension views are paired lateral X‑rays of the spine taken while the patient bends forward (flexion) and backward (extension). They assess vertebral alignment and abnormal motion—instability, subluxation, or failed fusion—by comparing positions and ranges of motion. Commonly used for cervical or lumbar complaints after trauma or to evaluate degenerative or postoperative change; radiation exposure is low.