Healthy spine. Coloured Xray of a side view of the healthy lower (lumbar) spine of an adult man. The front of the body is at right. The spinal column is made up of vertebrae (red), blocklike bones that protect the spinal cord and support the upper body. The projections at left are the attachment sites of muscles in the back. The spaces between the blocks of the vertebrae hold intervertebral discs (not seen), which cushion the spine against shock and allow a degree of flexibility. This part of the spine is subject to lower back pain. Rib bones are seen at top right.
