The lumbar spine is made up of five (sometimes four to six) vertebrae (its abbreviation is L). Lumbar vertebrae are massive in structure, with a large body, triangular shape to the vertebral foramen, and short and horizontally positioned spinous processes. Noteworthy is the fact that the costal processions (processus costarus) are located laterally (and not the transverse processes) as in the other vertebrae. The costal processes are the elusive remains of the ribs. The physiological anterior curvature of the lumbar segment (lordosis lumbalis) is associated with the upright standing of the body and the first attempts to walk.