Canning was diagnosed with mild inflammation of his right elbow joint, and he will be shut down for the rest of the season.
It's good that he is only dealing with mild inflammation, which will allow him to proceed with a "rest and recover" route rather than surgery. However, he won't pitch again this season, so he can be cut loose in all redraft leagues. Canning had a 4.58 ERA, 1.22 WHIP and 96 strikeouts in 90.1 innings during his rookie year. Jose Suarez is replacing him in the rotation.