Neuvirth was hurt while warming up before the Capitals' 3-2 shootout win over the Montreal Canadiens on Friday. He left the ice just before the start of the game and was replaced by Braden Holtby.
The Washington Post reported that Neuvirth stepped on a puck and slipped.
Dallas Stars center Tyler Seguin is day to day with concussion-like symptoms that resulted from a hit during a 2-1 shootout loss to the Chicago Blackhawks on Friday night.
Seguin, who missed Sunday's game against the Edmonton Oilers, also is dealing with a muscle issue, Stars coach Lindy Ruff said Monday.
In his first year with the Stars after an offseason trade with the Boston Bruins, Seguin leads Dallas with 12 goals and has 23 points in 24 games.
Pittsburgh Penguins center Evgeni Malkin, Detroit Red Wings defenseman Niklas Kronwall and Chicago Blackhawks defenseman Duncan Keith were named the NHL's "Three Stars" for the week ending December 1, the league announced.