Hitchcock said he doesn't know when McDavid, who leads the Oilers with 35 points (14 goals, 21 assists), will return.
"It went up and down," Hitchcock said of McDavid's status throughout the day. "He was out, he was in, he was out, he was in. At the end, he was out, both him and Spooner.
"Got to move on. You've got to be able to win games if you're missing one guy. It's not the end of the world."
Ritchie was a healthy scratch in the previous five games and seven of the previous eight. He had not scored since March 27 against the Philadelphia Flyers, and it was his first multipoint game since Dec. 3, 2017 (two goals against the Colorado Avalanche).
"You obviously want to be in the lineup every night," Ritchie said, "but I think there's a lot you can learn, a lot you can work on to make sure you're ready. It's not like I was injured or anything; I was able to work on my game. It was just a matter of me getting my legs under me early and just getting back in the flow."
Jason Dickinson gave the Stars a 1-0 lead at 10:59 of the first period with a one-timer while falling to his left knee at the right side of the crease, assisted by Janmark and Ritchie. Dickinson had not scored in his eight previous games.
Ritchie scored at 1:51 of the third period when he collected a loose puck after a turnover by Janmark to make it 2-0.
Jamie Benn gave the Stars a 3-0 lead with a power-play goal at 7:24 of the third period.
Jujhar Khaira scored Edmonton's only goal when he knocked in his own rebound at 14:36 of the third to make it 3-1. It was his first goal of the season.
Esa Lindell scored an empty-net goal while shorthanded at 17:46 of the third period for the 4-1 final score.
With McDavid and Spooner out, the Oilers played 11 forwards and seven defensemen. Leon Draisaitl played a season-high 25:25.
"The players are good enough to be able to go out there and create something," Draisaitl said. "They got that second goal against us. Our heads kind of went … they sunk down a little bit."