Bruce admits he was upset when Upson joined the Hammers in January as Birmingham were pushing hard for promotion back to the Premier League.
He also doubts Upson will be unable to get back into the international squad.
He said: "When asked the question of whether Upson could get back into the England side, my honest answer 'is I don't think so'. That is not meant to be disrespectful to the player.
"I think where we are blessed in this country in that we have fantastic central defenders. Really good ones.
"The most important thing for Matt is to remain fit and get over his serious injury.
"I think his reception back at Birmingham will be okay although the fans are a hard lot to call.
"I am pleased he has now got himself fit and I watched him last week.
"He played well for Birmingham and the peak for him was when he got himself into the England set-up.
"I wish him well and hope he stays injury-free to get on with his career."
Bruce, who feels his side have shown some promising early season form, admits it is important to get their first win as soon as possible and is looking for a successful outcome against West Ham following the opening day defeat at Chelsea and Wednesday's 2-2 draw with Sunderland.
He acknowledges it will put added pressure on West Ham boss Alan Curbishley but feels that is unfair after what the Hammers boss achieved last season.
Bruce said: "It was a minor miracle what he did last season and to be under pressure after only one game in the Premier League is ludicrous.
"He has only been there since last Christmas and is trying to gel the team and that takes time.
"I admit all Premier League clubs have thrown money around this summer. But perhaps not so much as Alan Curbishley has had but these are still early days."
Bruce is in an optimistic mood for Birmingham and added: "The pleasing point was how we have equipped ourselves in the Premier League so far.
"For a team which has just been promoted, I think we are better off than we were three or four years ago.
"The only problem is that everyone else has strengthened as well.
"But we look a far better team than what we had last year. I'm very pleased with that. It will take a little time to settle particularly the defence.
"Everyone I have brought in has something to prove either a bit of hunger, a bit of desire or to do well in the Premier League. This is their big chance.
"After the first two games I've been encouraged. Obviously we now need a win and home in the game against West Ham."