Simple answer: Works for some, doesn't for others. I use it on muscle pulls, strains, ankle sprains, when pf starts, and so forth and get good results. It doesn't do anything positive for my wife when she is injured.
http://www.dmso.org
has lots of, mostly pro, articles about it.
Gives you real strong garlic/cabbage breath and body odor.
Can burn if you use if full strength or too often -- what "too often" is varies with the user.
I get best results with the dmso/aloe mix. It is almost a gel thickness, sort of like hand lotion.
Do not ever put anything like Icy Hot, Bengay, or any other topical analgesic creams on it. DMSO heighten sensitivity and transfer and you can't stop it -- can get bad burns.
I am not a medical professional of any sort. I use it because it works for me.