02/10/2026
đ SPINE SERIES: MEET YOUR LUMBAR SPINE
Five bones. Built for support and movement!
The five vertebrae in your lower back are numbered L1âL5. These are the largest movable vertebrae in your spine, supporting much of your upper bodyâs weight.
đ˘ L1: THE SPINAL CORDâS NEIGHBOR
Your spinal cord usually ends around the L1âL2 level in adults. Below this point, a bundle of nerve roots continues down the spinal canal. Itâs called the cauda equina, Latin for âhorseâs tail,â because of its appearance! đ´
đ˘ L2: THE WEIGHT BEARER
L2 is part of your lower backâs support team. Like the other lumbar vertebrae, it has a large vertebral body, the main weight-bearing part of the bone. Lumbar vertebrae are much larger than those in your neck because they support greater loads.
đ˘ L3: ONE OF THE BIG FIVE
L3 sits in the middle of the lumbar spine. Together, these five sturdy vertebrae help support your upper body while allowing your lower back to bend and move.
đ˘ L4: THE HIP-BONE LANDMARK
An imaginary line joining the highest points of your hip bones usually crosses around L4 or the space between L4 and L5. Clinicians use this as an approximate landmark, although its position varies from person to person.
đ˘ L5: THE HEAVY LIFTER
L5 is the largest lumbar vertebra. It sits where your movable lower back meets the sacrum, the triangular bone at the base of your spine, helping transfer weight toward your pelvis.
đŹ Which fact surprised you most?
Follow along as our Spine Series explores the spine, one region at a time!