It's difficult to tell the root cause of lower back pain without the help of a chiropractor. If your pain is localized to a specific area and gets worse with movement, it's more likely to be related to a muscle. If your pain is more widespread and gets worse with sitting or standing, it's more likely to be related to a disc. The disc can bulge or get herniated, irritating the nerves in the spine and control the muscle on one side of the back down to the legs. A quick examination by a chiropractor can help establish the source of the pain and help avert further damage.