I came off of a horse when I was 18-landed straight on my tailbone. Somehow I was able to gather her up, put her back in the paddock and was pretty much on my stomach for the next few weeks. The Dr. said I'd compacted my spine, and tipped my tailbone. I was on vacation when I did this-the plane ride home was less then fun! That's been a "few" years ago, and I still can't sit straight. I am very much more comfortable sitting up over my hips, so the weight is not on the back end, but rather more my legs.