Word is that Jermaine O'Neil's hand continues to hurt and he is considering season ending surgery, and Chris Wilcox is out indefinitely with career threatening cardiac symptoms. The Celts are in deep doo-doo at center, having only 26 year old rookie Greg Stiemsma, who couldn't make anybody's 15 man roster for four years after college, and rookie JaJuan Johnson, who, despite being a "finished product" coaching wise, was only a 27th pick after four years of college ball, as players tall enough to play that position. Basically, their starting center for now is Bass, who is undersized even when he plays power forward.
The Celtics have had really bad luck over the last season and a half with "bigs". Last year, in games in which Shaq played 20 minutes a game, they were the best team in the league, but his ankle gave out. Jeff Greene and Ned Kristic came over from the Thunder for Perkins and Nate Robinson, but Greene, who had been resigned for $9 million a year and was being counted on as a 30 minutes-per-game sixth man, failed his physical and his contract was voided, and Kristic was deemed to not be worth the $5 million it would have taken to resign him. Troy Murphy and his $11 million a year contract expired and the Celts let the Lakers sign him for $1.3 million, which is all he is now worth due to physical deterioration, and they traded Semih Erden to Cleveland for their 2013 2nd round pick and because he wasn't worth any more than that.
The Celtics are nearly $30 million over the cap and have already used their mid-level exception on Wilcox, so all they can do is either sign a free agent who will play for the veteran minimum (about $1.5 million) or make a deal using the contracts of O'Neil or Wallace to facilitate a trade, but I don't know who would be available that might help them.