There are many potential sources of leg pain. The nerves that provide motor and sensory function to the legs start in the lower back. These are called the lumbar nerves. Leg pain that starts in the lower back and radiates down the leg is often referred to as ‘sciatica.’
Some causes of leg pain from a lumbar spine problem include:
Disk Herniation
where the soft cushion between the bony vertebrae of the spine herniates from its normal position and causes compression of the lumbar nerves