Arrieta -- who made his last start Sept. 14 after setting a new career high in innings pitched -- said Yocum's diagnosis was the same as team orthopedist Dr. John Wilckens.
"They said with the way it has been acting -- it hasn't bothered me -- he basically said there's no reason to do anything if you are able to throw effectively," said Arrieta, who has maintained that he has never been in any pain or discomfort from the spur.
Arrieta was also told by Yocum that having a bone spur is relatively common, and the 24-year-old was relieved he can avoid surgery, however minor the procedure, given that he has never had any health concerns.
"I've had [the problem] for a long time, and you never know with surgery," said Arrieta, who also spoke with Orioles president of baseball operations Andy MacPhail about his decision. "Anything can happen, even though it's minor. I think this is the best thing to do."
The Orioles were looking into the preventative measure given that Arrieta was already done for the season and it would be a few weeks of rehab at most. MacPhail said on Wednesday that the organization was fine with Arrieta's decision.