Hudson, who was promoted onto the senior list as the Magpies' nominated rookie prior to the season, will miss up to eight weeks, and is likely to mean he has played his last AFL match.
"It's not as bad as a shoulder reconstruction, but he's having a tendon reattached," Magpies football manager Rodney Eade told AFL.com.au.
"We reckon he'll be eight weeks and hopefully he's back in the finals for the twos (VFL)."
The 35-year-old has played seven games for the Magpies in two seasons on the club's list, but his tutelage of young ruckmen Brodie Grundy and Jarrod Witts has already paid handsome dividend.
The journeyman Pie's leadership in the VFL has also been a giant fillip for the club, with his experience and knowledge rubbing off on some of the club's most talented young players.
Hudson's long-term injury opens the door for rookie Kyle Martin to be elevated to the senior list.
Martin has averaged 24 disposals and two goals a game in the VFL and is the most likely of the Magpies' rookies to earn his chance and add to his tally of four senior games.
Hudson's 168-game AFL career has spanned four clubs (Adelaide, the Western Bulldogs, the Brisbane Lions and Collingwood) in 11 years.