Adam Reach put the Owls ahead after just 16 seconds and matters were made worse for Villa when former England international Terry was forced off through injury in the 21st minute.
Jordan Rhodes added a second for Wednesday just after the centre-back left the pitch, with Villa also losing Robert Snodgrass during the opening period of the 2-1 defeat.
The news was not positive for Terry, who posted a picture of his right foot in a support brace on Instagram after the match.
"Devastated is an understatement to how I'm feeling tonight," he wrote in an accompanying message.
"I have just had the news that I have broken my fifth metatarsal.
"I will be doing everything I can to get back fit as soon as possible."
Manager Bruce could not hide his frustration as Villa lost ground on the Championship's top four, lamenting the injury blow suffered by Terry.
"When you analyse it tomorrow that's when it will dawn on us that it's not just been a poor afternoon where we've got beat - which you accept - but the loss of key players is key for us all going forward, especially your captain," said Bruce, before the metatarsal break was confirmed.
Lost some momentum and JT injury a huge blow but we will go into the next xmas stretch positive— keith wyness (@retsub12) November 4, 2017
"That's the s*** industry we're in. A bad day gets worse and you're going along nicely and it kicks you in the b*******. Excuse my French, I do apologise.
"Let's hope it's not too bad. Let's hope it's six weeks rather than 12 weeks."