is where a leg “hold” is created by camming your knee/lower thigh up under some blocky, cracky, or roofy feature in opposition to your foot.
Includes all locks, bars, and holds that cause enough pain to cause an opponent to submit. Many of these holds can result in serious injury if the opponent does not tap out in time. A few popular submission holds are arm bars, ankle locks, knee bars, and neck cranks 
A submission hold that hyperextends the leg at the knee.