Ball hopes to return to training this week and boost City's defensive options for the visit to St Andrews.
Micah Richards remains out, although Richard Dunne and Nedum Onuoha shrugged off injuries to feature in the 2-1 win against Spurs before keeping a clean sheet in the 0-0 draw at Bolton last Saturday.
"It was just the timing of the injury that's frustrating really," Ball told the City website.
"I remember speaking to the press before the Everton game and saying that avoiding injuries was important at this stage of the season - now we've had Micah, Dunnie, Nedum and myself picking them up!
"There were a lot of us in the treatment room fighting to get back in time for the Tottenham game, Nedum and Dunnie made it, but because of the bruising I've got on the knee-cap, I've got to wait for that to settle down before I can join back in again.
"There's no major damage," he added. "It's just a case of a badly bruised bone and I've just got to wait for that to heal as quickly as possible and I'll be able to train pretty soon."
Sun Jihai is currently Sven's only senior defensive option on the bench and City need to beat Birmingham to have a realistic chance of qualifying for Europe this season.