Numbness, burning and tingles in both arms, hands, legs and feet. MRI of brain and cervix came back normal. Primary care doctor sees nothing wrong :- (?

Unexplained numbness. You're right, that is a tough case. When you have these symptoms in the arms and legs, sometimes it arises from the brain or the spinal cord, which explains your MRI studies. Sometimes it is caused by something with the nerves, the nerves in the arms and legs. For this cause, sometimes blood testing or nerve conduction tests are helpful. Hope this helps you!