The L4 or Fourth Lumbar Vertebra Viewed Inferior

Description

Oriented in an inferior view, the L4 vertebra is presented with the vertebral body anteriorly and the vertebral foramen centrally, bounded posteriorly by the laminae and the base of the spinous process. Laterally, the transverse processes project from the junction of pedicle and lamina, while the inferior articular processes sit posterolaterally, their facet surfaces directed to engage the superior articular facets of L5. The inferior vertebral notch contributes to the intervertebral foramen at the L4 to L5 level. Bone texture is rendered as natural cancellous and cortical contour. An inferior perspective is the cleanest way to appreciate the orientation of the inferior zygapophysial (facet) joints at L4, a joint line that governs coupled motion and becomes clinically loud in degenerative facet arthropathy. At L4 to L5, hypertrophy of the inferior articular process and capsular thickening can narrow the lateral recess, contributing to L5 radiculopathy and the pattern of neurogenic claudication seen in lumbar spinal stenosis. Facet tropism and pars interarticularis stress at this level also sit in the differential when evaluating mechanical low back pain and early spondylolysis. Use this plate for gross anatomy lab teaching on lumbar vertebral landmarks, for radiology correlation when orienting axial CT or oblique lumbar radiographs to the facet plane, and for spine surgery or pain medicine materials discussing medial branch blocks and facet joint injections at L4 to L5. It also suits textbook figures on lumbar motion segments and intervertebral foramen boundaries in adult male anatomy. Anatomical accuracy verified by SciePro's Medical Advisory Board.