Low Back Pain Low back pain is an ache or discomfort in the
lower part of the spinal column. It may radiate down into one or
both legs. The lower spinal column consists of small, stacked
bones (the vertebrae) that surround and protect the spinal cord
and nerves. Cross-section of Vertebral Canal with Spinal Cord in
the Center Copyright © Nucleus Medical Media, Inc. There are
many possible causes for low back pain, including: Lumbar Disc
Herniation With Pinching of Spinal Nerve Sciatica is irritation
of the sciatic nerve. It leads to pain that starts in the lower
back and spreads to the buttocks and down the back of each
thigh. The sciatic nerve is composed of several nerve roots that
start from the lower part of the spinal cord. These nerves form
a network that lead to individual nerves. These nerve bundles
travel deep in the pelvis to the lower buttocks. From there, the
nerve passes along the back of each upper leg and divides at the
knee into branches that go to the feet. Anything that causes
irritation or p