The team said Monday that Muzzin is out indefinitely with a cervical spine injury and will be re-evaluated in late February.
The 33-year-old Muzzin was injured in Toronto's 4-2 home loss to Arizona on Oct. 17 after colliding with Coyotes winger Clayton Keller.
The Maple Leafs had the veteran defenceman on injured reserve two days later and said at the time he would miss at least three games.
Muzzin, an effective penalty-killer and shutdown defenceman, has skated in four games with the Maple Leafs this season and recorded one assist.
Toronto also announced that TJ Brodie has been placed on injured reserve with an oblique injury. General manager Kyle Dubas said Monday that Brodie will be out a minimum of two weeks.
The 32-year-old Brodie, who missed Toronto's win over visiting Vancouver on Saturday, has two assists in 15 games this season.
In corresponding moves, the Maple Leafs recalled forward Pontus Holmberg and defenceman Mac Hollowell from the American Hockey League's Toronto Marlies.
This report by The Canadian Press was first published Nov. 14, 2022.
The Canadian Press