I just want to say, that's a great question, and a lot of accurate answers 😁. I work in a related field as well, and many people cannot wrap their minds around 'yes, there are symptoms in you leg (for example), but the cause is located at the peripheral nerves that become the sciatic nerve. Your leg is actually physically okay, at least for now.' Obviously when the nervous system isn't functioning properly, all of the other bodily functions will be affected as well. Resulting in a multitude of other issues.