Highmore, 26, dressed in two games during his recall to the Blues.
With the Thunderbirds this season, the Halifax, Nova Scotia, native has appeared in 47 games, leading the team with 34 assists and 46 points.
Overall, Highmore has collected 27 points (12 goals, 15 assists) in 139 career NHL regular-season games and 110 points (43 goals, 67 assists) in 144 career AHL regular-season games.