Fifth Lumbar Vertebra L5, Gross Anatomy

Description

Centered in the lower lumbar column, the fifth lumbar vertebra (L5) is isolated by color against adjacent lumbar vertebrae superiorly and the sacrum inferiorly. Its large vertebral body sits anterior to the vertebral arch, with stout pedicles projecting posteriorly to the laminae and a broad spinous process. Deep superior and inferior vertebral notches on the pedicles help outline the intervertebral foramina, bordered by the pedicles above and below, and positioned lateral to the vertebral canal. White intervertebral disc spaces separate L4 to L5 and L5 to S1. Attention to L5 is practical because this vertebra forms the mobile base of the lumbar spine at the lumbosacral junction. The L5-S1 level carries high shear forces, so this anatomy underpins teaching around spondylolysis of the pars interarticularis and anterolisthesis, as well as degenerative disc disease that can narrow the L5-S1 intervertebral foramen and irritate the exiting L5 spinal nerve. Pedicle contour and notch depth also matter when planning pedicle screw trajectories and appreciating why foraminal stenosis presents with radicular pain patterns rather than central canal symptoms. Use this plate in gross anatomy and musculoskeletal modules to orient learners to lumbar vertebral landmarks, or in spine surgery and radiology materials when discussing L5-S1 disc herniation, lumbosacral transitional anatomy, and fixation planning. It also reproduces cleanly for patient education on the low back and backbone. Anatomical accuracy verified by SciePro's Medical Advisory Board.