That sucks, I recently had a freak lifting exercise and witness one as well...I'll tell you about both of them and one funny one.
I was doing some incline presses with dumbbells, light weight warm up sets with 70 pound dumbbells. When is set them down I always look to the right to make sure I'm not putting them on my phone. As I as setting them down I suddenly felt this extrem pain in my left hand, the side I wasn't looking. I immediately opened my hand ( dropped the weight) grabbed my hand and started jumping around in pain. I realized I had hit my middle finger on the too of my cheap wal mart bottles water bottle while setting the weight down (shouldnt do much damage). I noticed a lot of blood everywhere so went to the bathroom, and didn't want to look so I wrapped it in a roll of paper towels, went and picked my son up from daycare and then went home and waited for my wife to get home (a nurse). Went to the ER about two hours later and was told that my finger was broken and my fingernail had literally blown through my skin (like from the root up). My finger was basically severed but held on by the skin, only place where skin was broken was where the nail blew through. They had to finish removing my nail and said it would it come back, but it did sort of.
The thing I witnessed was strange. A guy was squatting about 600 lbs and had a really wide grip. I was watching him retail when I noticed something strange fly over to the side. Turns out his grip was to wide and when he reracked the weight he smashed his hand on the rack. The thing I seen fly over to the side was his entire thumb, it flew a good twenty feet across the gym.
The funny thing I seen was this skinny guy who had just started within out, like most newbs he was spending a lot of time at the bench. Eventually He put about 245-275 on there and didn't use any rabbit ears to hold the weight (he was struggling with 135 to begin with). The second he pulled it off the rack one of his arms gave out and the bar on that side fell down. Being no rabbit ears all of the weight dumped off, and now the other side was the only one with weight. With the sudden change of weight the heavy side then fell down, and the rotation of the weight bar pole vaulted te kid a food fifteen feet away from the bench and he probably was about 8 feet in the air. After he left everybody started laughing pretty hard.
