Wall Board is cracked behind the faucet?

I have a pretty major crack in the wall board behind the faucet in the shower/tub. The tiles are recessed in due to the wall crack and now the grout is starting to crack from the wear. I can get behind the wall where the studs are, can I sure up the wall and reseal the tiles, or do I need to put in a new wall board and re tile? I am planning to change the fixtures, but need to fix this first.