Not surprising. He hasn't been himself since the 53 pt game vs the Wiz. Given the pounding he has taken, it's for the best. I just hope it's nothing that could cause some long term issues.
The way he plays the pounding he takes is always going to be a concern. I used to marvel at the way Larry Bird both absorbed and dished out punishment banging with bigs back in the day and ultimately his body broke down a little sooner than everyone might have hoped.