Here's a link to a lithuanian interview Dmo gave today.
Basically he said that they didn't even check him and it was just an excuse to cancel the trade. He's consulting his lawyers because this "information" about his health hurt his value in the upcoming free agency.
Edit : Said he spent the All Star break in Vancouver, working on his back with a specialist, will go there again, once the season is over.
He also said he wasn't angry at the Rockets for trading him, because it was a really good deal, and he heard that they tried to offer other players, but Pistons
