The 25-year-old Argentinian suffered a broken bone in his right foot during Saturday's 2-2 draw against AC Milan and, after undergoing surgery this week, he will be sidelined for at least 60 days.
"I want to recover as soon as possible and return to help the team," said Larrondo, who joined Il Toro from Fiorentina in the summer.
Larrondo's setback capped a disappointing week for Torino coach Giampiero Ventura.
The Granata thought they had secured their second win of the Serie A season last weekend only for Milan's Mario Balotelli to clinch the draw from the penalty spot with the last kick of the game.
"It is difficult to accept the result," Ventura said. "We deserved the win and I say that with great humility.
"The outcome did not reflect our domination over Milan in the game.
"The win would have given us a big confidence boost."
Bologna head into the encounter at the Stadio Renato Dall'Ara still searching for their first win of the campaign.
Just like Il Toro, Bologna's main aim this campaign will be to avoid the drop and coach Stefano Pioli hopes his side can soon be rewarded for their efforts.
Bologna held Udinese to a 1-1 draw in Friuli last weekend having previously taken a point from Sampdoria.
"My team is getting better game after game and this is a good sign," Pioli said.
"Of course, it would be good to have more points on the board but I'm sure that our hard work will soon pay off."