This is nothing big for you guys to freak out about. Just give him time to heal up.
NBA.com: The Lakers said in July that Bynum would be available on a “limited basis” during training camp after his operation to repair the knee he dragged through the playoffs and Finals, earning the respect of his teammates in the process. Bynum in fact will not participate in any preseason games. He will travel with the team, but he has not yet been cleared to begin basketball activities on the court. The Lakers hope Bynum will be able to do some work on court later in the preseason. With Gasol also sitting out the worlds, he’s likely ready to handle heavier minutes early on until Bynum is up to speed.