As you can see in the chart below, all the nerves in the spine go to organs and glands, as well as muscles. If a patient comes into our clinic complaining of butt pain, I am going to examine his lumbar spine because the lumbar spine nerves innervate the butt. However, I am also going to assess his colon and prostate, because those organs share the same nerves as the butt. A male patient could have an inflamed prostate and his only symptoms might be butt pain or pain in his heels. The pain won't go away until the prostate is fixed.
If the patient is female and comes into the clinic complaining of right shoulder pain and inability to lose weight, I am going to examine her thoracic spine and her gallbladder function. The nerves that innervate the shoulder muscles also innervate the gallbladder. If the gallbladder is inflamed, the muscles in the shoulder will also be inflamed.
Do you have a dry, non-productive cough? You could have parasites or heavy metal toxicity.
How about wrist pain or elbow pain? You could have an ulcer or a lung infection.