Back Pain Tips

I went to my Neurosurgeon today for a back injury. He done some kind of test and told me I had a “certain” disease. I can’t remember the name because he found more than one problem. I do remember the other diseases name. All I can tell you is that he flicked my index nail “kind of” hard a few times. He said he was checking to see if my thumb moved when he did so. It did, which meant I had this disease. For the life of me I can’t remember what he called it. If anyone could help I would greatly appreciate it.