Lapierre had the surgery Thursday after playing through pain for most of the season. The 24-year-old set career highs with 15 goals and 13 assists in 79 games during the season.
Defenseman Mathieu Schneider underwent arthroscopic surgery on his shoulder last week. The 39-year-old was first injured April 4 against the Toronto Maple Leafs, forcing him to miss two regular-season games and two playoff games.
Schneider had five goals and 12 assists in 23 games with Montreal after returning to the Canadiens in a Feb. 16 trade with the Atlanta Thrashers.