The 40-year-old has been sidelined since he sustained the injury at the end of April, with the defender's retirement slated for just a few weeks after.
Due to not being able to end the season as an active member of the squad, Zanetti was offered a one-year contract extension and took a place on the bench for last weekend's 3-0 win over Udinese following his gruelling rehabilitation.
Zanetti did not play in Udine, but did make his comeback as a late substitute in Saturday's 2-0 win over Livorno at San Siro and confessed it was an emotional occasion.
He told Sky Sport Italia: "I feel great emotion, as at the age of 40 after six months out it wasn't easy.
"Right from the day of the operation, I always said I wanted at least one more game in front of my fans. I could ask for nothing more.
"I have to thank the immense crowd, the president, all those who stayed close to me from the medics to my team-mates and everyone who wanted me to come back on to the pitch.
"I'm glad my comeback coincided with an important victory for us."
Inter head coach Walter Mazzarri added: "There's something special about him (Zanetti). He's world class and was a reassuring presence for the team as soon as he came on."
Zanetti also had kind words for club president Massimo Moratti, who, after selling the club to businessman Erick Thohir, attended his final home match as majority shareholder.
"Our bond goes beyond that of president and captain," Zanetti added. "The president deserves this applause and more for all he's done for Inter.
"We need to get back into the race for something important. The table will tell us where we end up, but with this spirit we can go far."
