Hi, Thanks for writing in. The lower back is made of 5 small bones aligned on top of each other. There are small discs in between these bones. The spinal canal passes at the back through a hole formed by the posterior elements of the bones. On each side between the bones, there are small foramen or holes through which nerves originating from the spinal cord pass through. In your case, one or more discs in the lower back region is displaced and herniated backwards. This can cause pressure on the nerves passing through the foramen and this leads to severe pain. The can can also happen when the disc is in close contact with the spinal cord covering in the spinal canal which is also known as thecal sac. Treatment for thecal sac compression and nerve root compression is first injecting steroids in to the areas of nerve compression. If this does not relieve the pain then the pressure on the spinal canal must be decompressed by surgically removing the laminae which forms the posterior elements of the vertebrae. This is called laminectomy. However, the extent of pain relief after surgery differs in each case and some patients can still have the pain.