Flash freezing can work, but it's almost impossible for something as large as a human body.

Cryoprotectants also do this pretty efficiently -- they prevent crystallization, which leads to "vitreous" ice, which has more or less the same structure as liquid water and so doesn't expand much. I think they do use that when freezing people, but the problem is that even if you fill the blood vessels with pure ethylene glycol, it diffuses very slowly, and it takes hours to get into cells which are far from large blood vessels. They dont diffuse the cryoprotectant in that thoroughly, though, because that'd take so long the body would have started to decay too much.

Edit: oops, the article talks about vitrifying agents. They make it sound like they're not effective, but as I said above, they're very effective if you can get them in every nook and cranny of every cell, which is a losing battle.