 in human anatomy, the lumbar vertebrae are the five vertebrae between the rib cage and the pelvis. they are the largest segments of the vertebral column and are characterized by the absence of the foramen transversarium within the transverse process (as it is only found in the cervical region), and by the absence of facets on the sides of the body. they are designated l1 to l5, starting at the top. the lumbar vertebrae help support the weight of the body, and permit movement. == human anatomy == === general characteristics === thumb|left|lumbar vertebrae these are the general characteristics of the first through fourth lumbar vertebrae. the fifth vertebra contains certain peculiarities, which are detailed below. as with other vertebrae, each lumbar vertebra consists of a vertebral body and a vertebral arch. the vertebral arch, consisting of a pair of pedicles and a pair of laminae, encloses the vertebral foramen (opening) and supports seven processes. ==== body ==== the vertebral body of each lumbar vertebra is large, wider from side to side than from front to back, and a little thicker in front than in back. it is flattened or slightly concave above and below, concave behind, and deeply constricted in front and at the sides.gray's anatomy (1918), see infobox ==== arch ==== the pedicles are very strong, directed backward from the upper part of the vertebral body; consequently, the inferior vertebral notches are of considerable depth. the pedicles change in morphology from the upper lumbar to the lower lumbar. they increase in sagittal width from 9&nbsp;mm to up to 18&nbsp;mm at l5. they increase in angulation in the axial plane from 10 degrees to 20 degrees by l5. the pedicle is sometimes used as a portal of entrance into the vertebral body for fixation with pedicle screws or for placement of bone cement as with kyphoplasty or vertebroplasty. the laminae are broad, short, and strong. they form the posterior portion of the vertebral arch. in the upper lumbar region the lamina are taller than wide but in the lower lumbar vertebra the lamina are wider than tall. the lamina connect the spinous process to the pedicles. the vertebral foramen within the arch is triangular, larger than in the thoracic vertebrae, but smaller than in the cervical vertebrae. ==== processes ==== the spinous process'
Bones_of_the_thorax