Hitching or ramping a deadlift to me, is essentially anytime the bar passes the knee and the knees drive forward or under or past the bar. A perfect deadlift should have the knee and hip joints getting closer to lockout the entire way through the lift, if there is an increase in knee angle as the bar passes the knee (knees come forward and increase their bend) than that is a hitch to me. What is a hitch really to me? A RED LIGHT, a NO LIFT. It is on par with the butt coming off in the bench which may happen on a hard grinder occasionally, yet so many people train their deadlift and allow the hitch every session.

Before we get into technique we will see physiologically what happens. 

As the bar comes off the floor and you push into a vertical shin position, your hamstrings move into an extreme amount of tension. The knee joint becomes less flexed as it straightens placing all the tension on the hip as it is still fully flexed. This is called loading your hips or loading your hamstrings. The tension is loaded and is available to use once the bar passes the knee for you to whip it back to lockout. Now. When the bar passes the knee and your knees come slightly forward, you essentially lose all the tension you just built in the hamstrings and now that you are not stiff legged and horizontal, you are upright and have both the knee joint and the hip joint to lockout versus just the hip joint to lockout. Now that the tension has dissipated from your hamstrings the demands need to come from some where else. This is when the quadriceps turn back on after being dormant since the push off the ground, and you get that pop of the bar or hitch or ramp which makes people believe they snapped their deadlift into the lockout position but in reality they had just hitched it. Red lights in my book.

Two joints are harder to lockout than one, so we should make the main goal to lock the knees out/back as quick as possible, which gives a rigid lower body for your glutes to fire to the maximum and drive forward to lockout. If your knees are noodley (I believe thats the technical term) and unlocked and your powerful glutes/hips try to drive forward to lockout, all that happens is you drive your knees under the bar and hitch it. So many people are closer to locking out the bar than they think but they concentrate more on their hips coming through, which only drives them into the stereotypical leaned back deadlift everyone thinks about. If you lock your knees out ASAP, once the bar gets to the knee, you essentially wedge your hips right through the bar and are nice and upright at the finish position. Also, you will usually lock your deadlift out a couple inches lower than normal, a couple inches in reality could be a ton of poundage you can gain on the bar.

Minor cues for big success. Just thinking about the lift differently can go a long way, no special exercises or training protocols, just actually thinking about certain elements that will help you hone a skill that so many wish they could achieve, a heavy ass deadlift! The biggest thing is to think about making the second goal after breaking the floor to lock out your knees. Where this goes wrong is that people will break the floor and just straighten there knee joint, not good. The end goal is still to get the bar up, so as long as your exerting force the bar must be moving up aka keep your chest and head moving up as they are attached to the bar. While your knees are locking out and your head and chest are driving tall, you will resemble the pull of a Weightlifter doing snatch or clean & jerk. Your shoulders will be slightly ahead of the bar, you will be vertical shinned, and the amount of tension in your hamstrings should be scary. Are you frightened? I hope so, because that freaky amount of tension will make you want to get out of that position as soon as possible, which is how we whip the bar back quickly for that speedy hard lockout!

Drills. Certain drills in warm up can be successful such as paused deadlifts at the knee, where in you would make sure the bar is close to the body, shins are vertical with tension in the hamstrings, and head and chest is tall ready to whip it back like a romanian deadlift. As well during warm up, you can start the bar further away from your shins on the floor, which makes your brain think about sweeping the bar back during the lift versus having it too close and going around the knee and not noticing that your shins are not going vertical. By sweeping the bar back, your brain thinks back with the whole body and your knees will end up driving back as well.

End of story, hitching is a sin and if you want to be a dead legend than you need to clean up your act or be sent to hitch hell.