Saw it on Facebook, and it might be a famous clip by now: a guy is lying back on an exercise machine of some kind, and is pressing upwards a massive stack of weights. He pushed a couple of times, and then his left leg snaps backwards. What sort of injury do you suppose he incurred? It was obviously painful AF.
Probably snapped the ACL or PCL as well as tearing the calf or glute tendons to the knee. Ouch. (Pats his repaired but not fully healed quad tear affectionately.)
Very possibly other damage to the joint surfaces, meniscus, side tendons etc.
If the leg folded sideways, ACL.
if it folded up, towards the belly, then its PCL
If it folded at the shin area, then it broke the tibia.
It could be an old injury failing,
but likely if it was a massive weight, he’s pushed his legs straight and then the leg has folded upward , beyond straight … basically he found out his muscles were stronger than his PCL
I had a roommate once who was watching a football game, and called me in to watch the slo-mo replay, because a guy’s knee folded backward.
BTW, that “bounce” at the top of the press is called “hyperextending” your knee, and I see guys at the gym doing it all the time. If they look like they are really in danger of hurting themselves, I’ll say something.
don’t think that knee is ever going to be quite right again…