Harrison had the procedure on his lumbar and will likely remain hospitalized for two days.
The 28-year-old had two back surgeries last season and attempted to come back this season before experiencing discomfort. He hopes to return at some point in 2015.
Harrison, 28, signed a five-year, $55 million deal in January 2013 after winning 18 games. He was 1-2 with a 5.79 ERA in six starts since signing that deal.
Harrison was 32-20 with a 3.34 ERA in 62 starts in 2011 and 2012, pitching nearly 400 innings in that span.