Medical staff from the city's Scarborough Hospital joined a team from the zoo's Wildlife Health Centre to perform surgery on the Western lowland gorilla named Sadiki late last month.
Sadiki had fractured his right fourth toe in December and developed an infection in his bone and a septic joint.
The zoo says that after consulting with an orthopaedic surgeon at the hospital, it was agreed that Sadiki needed a partial amputation of his toe to get rid of the infection.
The surgery took 20 minutes and took place at the zoo's gorilla habitat.
The zoo says it approached the hospital because it wanted the best care for the endangered gorilla.
Dr. Michael Bushuk, an orthopaedic surgeon with Scarborough Hospital, said his team was "honoured" help with Sadiki's care.
"The surgery went extremely well and Sadiki is recovering nicely from the procedure," he said. "We wish Sadiki the best and hope his recovery continues to go smoothly."