One of the Flyers’ top forwards could potentially miss the start of the season. One of the Flyers’ top forwards is going to be out of commission for a while. Joel Farabee underwent successful disc replacement surgery in his cervical region Friday morning, the Flyers announced. The 22-year-old is expected to recover in 3-4 months. The Flyers begin training camp on September 21, so it’s likely Farabee, at the very least, will miss a significant portion of the team’s first training camp under new head coach John Tortorella. INJURY UPDATE: Flyers forward Joel Farabee underwent successful disc replacement surgery in…