Perunovich will undergo the surgery on Thursday after suffering the injury in a pre-season game on Sept. 27 against Chicago.
The team says the injury is unrelated to the torn left labrum that kept Perunovich sidelined for the 2020-21 season.
The five-foot-10, 174-pound defenceman recorded six assists and eight penalty minutes in 19 regular-season games for the Blues last year. He also had four assists in seven playoff games.
The Blues selected Perunovich in the second round (45th overall) of the 2015 NHL Draft.