The Lumbar Spine
The lower back or lumbar spine is made up of five bones, called vertebrae. In between each vertebra is a softer structure, known as a disc. The discs are spongy and
act as shock absorbers as we move, bend, and twist.
Behind the vertebrae and discs is the spinal canal, which houses the spinal dura and cauda equina*. At each level of the lumbar spine, nerves exit the spinal dura and carry signals to and from the buttocks, legs, and feet.
The laminar arch or the lamina is the “roof” of the spinal canal. The lamina forms a bridge which connects to the vertebral bodies. Together these bony structures surround
and protect the dura and nerve roots. The laminae are connected to one another by articulating joints, which are known as facet joints.
* The dura is a thick membrane which surrounds the cauda equina. The cauda equina, or “horse’s tail” in latin, is a bundle of spinal nerves in the lumbar spine which provide motor innervation to the muscles, joints, and organs of the lower body.
