I rather think I qualify for that one...lol...in the very early 90s, I was hit from behind by a gold Monte Carlo while riding my motorcycle through Providence, RI...I was propelled off the bike and hit a big stone wall in front of Johnson and Wales University head and right arm hitting first...I had amnesia for a couple of hours and my right arm was just hanging down, (I shattered the elbow radius bone which they had to piece back together).That is about the worst helmet scrape I have ever seen.
The helmut was not only scraped from hitting the wall head first, but also broke into two distinct halves...The paramedics placed what was left of the helmut on top of my chest to alert the shock trauma unit at RI hospital that this was a motorcycle accident with head injury...Needless to say I had a major concussion with massive headache to go along with it...Demerol was my friend for a while...lol.