Simmons left the bubble for the procedure. He will remain in Philadelphia to rehab.
The 76ers initially announced the injury Saturday.
“After consultation with the 76ers medical staff and several specialists, Ben Simmons will undergo surgery in the coming days to remove a loose body in his left knee,” a team statement reads.
On Thursday, he was diagnosed with a a subluxation of his left patella — a partially dislocated knee cap.
Simmons a long shot to return
ESPN’s Adrian Wojnarowski initially reported the 76ers hadn’t ruled Simmons out for the season, but that changed following Simmons’ surgery. The 76ers are currently the 6th seed in the Eastern Conference.
Simmons, 23, has averaged 16.4 points, eight assists and 7.8 rebounds this season, his second straight as an All-Star. He suffered a pinched nerve in his back earlier in the season that cost him the last eight 76ers game before the NBA shut down for COVID-19.
Shake Milton took over 76ers point guard duties to start bubble play as Simmons shifted to a point forward role. The moved pushed Al Horford to the bench. He’ll likely return to a starting frontcourt role alongside Joel Embiid in Simmons’ absence.
More from Yahoo Sports: