Homonculus
Paralysed cyclist is 'cured' by bike crash and now has Olympic hope | Mail Online
I have added the above link to show how little is understood while you talk of mild back pain mine was diagnosed as impact bruising to the spinal chord and I was told that I would have to live with dragging my foot.
I know a farmer well who had an operation for back problems and after all that has ended up the same and he states worse than before.
I was glad I took my own route and that was over 20 years ago.
Pace