No specific date has been set for Hedges' surgery, but the injury typically requires a recovery period of at least six to eight weeks.
The 23-year-old Hedges was ranked as the club's top prospect in 2014 and No. 2 in '13 and '15. He's no longer technically a prospect, because of his time spent in the Majors last season.
A right-handed hitter, Hedges has long been known more for his defensive prowess than his bat. In his first cup of coffee last season, he hit .168 in 56 games.
Before the injury, however, Hedges appeared to be turning a corner offensively, after leading the club in batting average (.394) and OPS (1.117) during Spring Training. Many had speculated Hedges' emergence could potentially make catcher Derek Norris available via trade.
AJ Cassavell covers the Padres for MLB.com. Follow him on Twitter @ajcassavell. This story was not subject to the approval of Major League Baseball or its clubs.