The 27-year-old center was in the lineup for Tuesday's game in Buffalo and hasn't missed a contest since joining Vegas for the 2017-18 season.
It's unclear how many games Karlsson is set to miss, as the team will play three more times before a nine-day break beginning Jan. 22 that includes the All-Star Game and a bye week.
Karlsson has posted 34 points in 49 games on Vegas' top line this year. He's averaging over 19 minutes per night and winning a career-high 51.2% of his faceoffs.
The Golden Knights will square off against the Ottawa Senators on Thursday, marking their first game since the firing of head coach Gerard Gallant.