Lack of blood flow (ischemia) is the most common cause of back pain. The disc is poorly perfused even under optimal conditions. Everybody knows that the brain and the heart need blood supply, but so does the spine. Too often the search is only for the "pain generator," and the "underlying cause" has been forgotten. We are looking at the TREE with a microscope, but we've forgotten to look at the FOREST. If all the trees have Dutch Elm disease, will...