Via a Flyers press release:

Philadelphia Flyers forward Bobby Brink recently underwent surgery to repair a torn labrum in his left hip. Dr. Christopher Larson of Twin Cities Orthopedics in Minneapolis performed the surgery.
 
He is expected to return to play in approximately five months.
Anthony broke this news back on July 10th. The injury was not related to playing hockey, but instead offseason workouts:

Ant then followed up with Chuck Fletcher about how long Brink would be out and Fletcher said this:

“I don’t envision any scenario where he’d miss most of the season.”

Let’s say Brink returns in exactly five months, then he’ll have missed 35 games. If it goes 19 days longer, it’ll be 42 games, which would be MOST of the season.