The experienced midfielder has picked up yet another problem and is expected to be out of action for up to three months
The Belgian midfielder featured from the start in Sunday evening's encounter, but was forced to leave the pitch after 53 minutes of play.
Mudingayi underwent further examinations on Monday to determine the extent of the knock, and Inter have now released a statement confirming his Achilles problem.
"Gaby Mudingayi underwent tests at Pavia's IRCCS Policlinico San Matteo on Monday after being forced off the pitch in the 52nd minute of last night's match between Inter and Torino with an injury.
"The exams, carried out under the supervision of Inter's chief of medical staff Franco Combi, revealed that the midfielder has torn his Achilles tendon."
The 31-year-old has only made nine Serie A appearances for Inter since joining the club on loan from Bologna in the summer transfer window.