My one mountain biking accident happened on the first day of summer after my freshman year of high school and was caused by a deep rut at the bottom of a relatively short but steep hill. I was trying to impress my riding buddy by not using my brakes on the way down. I hit the rut and that's about the last thing I remember before waking up with a concussion about 30 seconds later. Upon hitting the rut, the handlebars ripped from my hands and turned 90 degrees. My head/helmet smashed into one side of the handlebars, and my collarbone hit the column, causing a hairline fracture. My friend said I was totally out of it and was babbling nonsense as we walked the biked back the mile or so to my house.
I'm really glad I was wearing a helmet.
