reacher had his weight on his left foot , and he had his right foot moving a split second after the wrench , driving the same way at the same speed , maybe even a little faster , and before the wrench stopped moving backward and started moving forward the heel of reacher 's boot met the big guy 's knee and drove right through it , smashing the kneecap deep into the joint , bursting it , rupturing ligaments , tearing tendons , dislocating the joint , turning it inside out , making it fold forward the way no knee is designed to go .