The procedure, to be performed in Los Angeles, will repair a herniated disk that has bothered Kotsay, 31, for the past two seasons. He said there is no exact timetable for his return to the defending AL West champions, but it likely will take 8 to 12 weeks of recovery time.
"I'm being given the opportunity to have a procedure the doctor feels good about, to get me to a healthy state as opposed to battling to stay on the field like I did the last two seasons," Kotsay said in a telephone interview Tuesday night from Southern California. "I've always had the problem. It was a matter of determining whether the herniation was causing my symptoms."
Kotsay left the A's Phoenix training complex for Southern California late last week to seek other medical opinions and undergo further tests. He has not practiced since Feb. 26, when he first complained of stiffness in his back. Kotsay underwent an MRI test two days later.
"It's always been there and that's been an option," he said of the surgery. "I haven't pursued it because I really thought I could function by doing rehabilitation and taking the steps to get through the season. The last two years have been very frustrating both mentally and physically. I've had one whole season with Oakland in 2004."
Kotsay, who batted .275 with seven home runs and 59 RBIs in 129 games for Oakland in 2006, said he will spend three weeks doing little other than resting after the operation.
He said during FanFest on Jan. 27 that he was feeling "really good" and thought he had taken enough time off in the winter to let his back finally calm down. Once it flared up again early in spring training, the arthroscopic procedure seemed to make the best sense.
"I wasn't into an aggressive baseball activity at that point," he said. "I did all I could fundamentally to prepare myself. I go into every offseason preparing to strengthen my core and give me more flexibility to play with that condition."
Kotsay, who made the playoffs last October for the first time in his 10-year major league career, started 96 of the A's first 111 games through Aug. 6 but the back problem limited him to 25 starts over the final 51 games.
Aside from his first big league season in 1997 when he played in just 14 games for Florida, Kotsay matched his career-lows in home runs, runs (57) and extra-base hits (39). He also grounded into a career-high 18 double plays.
He hopes to soon be feeling like himself again, healthy and ready to help the A's in the second half.
"You're discouraged because you prepare yourself for a season that you're anxious to start, and it didn't start off the way I would have liked it to," he said. "But to have an answer to the problem I've dealt with the last 2½ years, it's going to be encouraging to get back on the field this season healthy. I have a definitive plan for how I'm going forth from this point forward. I'll start my rehab and look forward to a speedy recovery."