I am currently 2.5 years out, and recently started using an inversion device called "invertrac". I chose it because you do not hang from your ankles, but instead tilt forward over a support pad that is at hip level, so you are hanging from your waist. I have avoided hanging prior to this, partly because of concerns some skiers have about stretching the knee ligaments. So far I am loving it, and it really solved some painful back issues I was having at the start of the year. It was interesting to note in their instructions, that you should not hang from the device if you have a hip replacement. I have noticed that my hip can feel a little stretched out ( it does not feel like a particularly good thing) after hanging, but it is very minor, and only last for a minute or so. The benefits for my back have been outstanding, so I am sticking with it. Just a few minutes at a time, a couple of times a day.