I have had the L punch. My neurologist told me that it can show if there is inflammation. I went ahead with it, it was the most horrific experience of my life. Sending a massive electrical shocks down my leg. I then ended up in A & E with a post lumber punch headache.

The lunber Punch didn't reveal anything. I have NLD SFN, i've had the skin biopsy. This was the only thing which showed abnormal.