The 27-year-old joined the Blues from West Ham on a free transfer in 2011.
“His versatility is a big thing for us as he can cover different positions,” boss Lee Clark told the club site.
“As well as midfield he can play as a full-back, although I ultimately think that as he goes on he could be a decent centre-half because he’s an aggressive player, he’s got good aerial ability and he’s mobile.
“In terms of football he’s still young, but he’s a very experienced player in terms of the games he’s had for a player of his age.”
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