The L3 Vertebra

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The L3 vertebra is in the middle of the five (5) lumbar vertebrae in the lower back portion of the spinal column. Because of the substantial weight-bearing role of the L3, a role it shares with all the lumbar vertebrae, this bone's vertebral arch and cylindrical centrum (vertebral body) are massively built-among the largest of the moveable vertebrae. The centrum is wider than it is deep and more or less flat on its superior and inferior sides at the articular joints with the superjacent L2 vertebra and the subjacent L4, with cushioning intervertebral cartilaginous discs in the space between each joint. Characteristically, the vertebral body does not have articulating facets. Short, notched pedicles connect to thick laminae in the vertebral arch, protecting a relatively wide, triangular vertebral foramen through which the spinal cord runs. The transverse process on each side is long and thin, lacking transverse foramina. Superior and inferior articular processes and facets articulate with the lumbar vertebrae above and below the L3. Its spinous process is very large, nearly rectangular in shape, and extends horizontally from the vertebral arch as a strong attachment point for the muscles of the lower back.