Aluko, who missed the second half of last season due to Achilles surgery, had been sidelined recently with a calf problem but was named in Hull's starting XI to face Sunderland last Saturday.
However, after complaining of discomfort in the warm-up, he was withdrawn and Bruce revealed on Thursday that the 24-year-old is now facing a lengthy lay-off.
"We've had some bad news. It was confirmed that Sone Aluko has torn his Achilles slightly," Bruce said.
"That's put a dampener on everything. He broke down in the warm-up last week and it’s been confirmed there's a tear in his Achilles that will keep him out until at least February.
"There's one or two specialists looking at him and we'll look for the best way forward for him. He's certainly going to be missing for the next eight to 10 weeks I'd have thought.
"It's tragically hard luck on Sone. He's had a few problems with it before and we thought we were over the situation.
"It's been an ongoing issue. Whether it's related (to his previous Achilles problems) we're not quite sure."
The Nigeria international has been a regular in the Hull side this season, making eight appearances and scoring the winning goal in a 3-2 victory at Newcastle United back in September.
