The lumbar vertebrae are the five large bones located in the lower back, labeled L1 to L5. They are the largest vertebrae in the spine, designed to support the weight of the upper body and allow for a range of movements, such as bending and twisting. These vertebrae are crucial for maintaining posture and stability. Each lumbar vertebra has a thick, sturdy body and a short, broad spinous process. The lumbar region is also where many important muscles and ligaments attach, contributing to the overall function of the spine and lower back. Proper health of the lumbar vertebrae is essential for mobility and comfort.