L5 — fifth lumbar vertebra (Vertebra lumbalis quinta)
Educational content only — not medical advice.
Anatomy
L5, the fifth of five massive lumbar vertebrae carrying the trunk's weight: a broad kidney-shaped body, a hatchet-shaped horizontal spinous process and slender transverse processes. The largest vertebral body with the longest transverse processes; the iliolumbar ligament anchors it and it bears the greatest shear at the lumbosacral junction.
Clinical notes
Lumbar disc herniation at L5 may compress the S1 root, producing classic sciatica with pain below the knee.
Related structures
Educational references
FAQ
What is the role of the L5 — fifth lumbar vertebra?
L5, the fifth of five massive lumbar vertebrae carrying the trunk's weight: a broad kidney-shaped body, a hatchet-shaped horizontal spinous process and slender transverse processes. The largest vertebral body with the longest transverse processes; the iliolumbar ligament anchors it and it bears the greatest shear at the lumbosacral junction.
Why is the L5 — fifth lumbar vertebra clinically important?
Lumbar disc herniation at L5 may compress the S1 root, producing classic sciatica with pain below the knee.
Source & license
Derived from Z-Anatomy (Gauthier Kervyn et al.), CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/); upstream geometry from BodyParts3D, © The Database Center for Life Science. license details