The spinal cord does not run through the lumbar spine (lower back). When the spinal cord ends at the lower thoracics spine, nerve roots from the lower and sacral areas go off the lowest end of the spinal cord like the tail of a horse (cauda equina) and leave the spine. Given the fact that the lumbar spine has no spinal cord, and covers a large area of space for various nerve roots, devastating injuries (e.g. big herniated disc) may not cause loss of function in the legs (also known as paraplegia).
In a human, the spinal cord is broken up into segments based on the nerve roots that are hooked on to it. The nerves which run along the spinal cord are made up of eight cervical, twelve thoracic, five lumbar, five sacral, and one coccygeal nerves. These nerve roots go through the bony canal, and at each various degree a couple of nerve roots leaves from the spine.
In the neck (cervical spine), the nerve root is given the name for the lower area that it runs between. (For example, the C8 nerve root at C7-C8 area). In the lower back (or lumbar spine), the nerve is named for the top area that it is between. For example, C7 nerve root at the C7-C8 segment.
Nerves that go to the following level pass on top off a fragile location in the disc area, and that is the explanation discs herniate (extrude) exactly below the nerve root and have the ability to create leg pain (also known as sciatica or radiculopathy). Miami Injury Attorney Justin Ziegler has many years of experience achieving significant settlements for injured accident victims for injuries to nerve roots, herniated discs, bulging discs as well as back and neck injury.