Hogg, who sustained the injury during Warriors PRO14 clash against Munster earlier this month, travelled with the rest of the squad to South Africa last week for the back to back matches against Cheetahs and Southern Kings.
After failing to feature at the weekend the decision was taken for the Scot to fly back to Scotland to assess the injury.
It's now been established the 26-year-old will require surgery to fix the issue.
The exact timescale for how long he'll be out won't be known until after the operation.
European Champions Cup campaign begins next month with matches against Saracens and Cardiff Blues.