Kitna's status for the regular-season finale at Philadelphia is uncertain.
"It's just injured, I guess," said Kitna, who completed 12 of 20 passes for 115 yards with one touchdown and two interceptions before leaving the game late in the first half. "I can't do any athletic movements and things you got to do at quarterback. Anything that requires any torque."
Kitna suffered the oblique injury on a 2-yard touchdown pass to Jason Witten with 5:11 to play in the second quarter.
Kitna had gone out for one play earlier in the drive after being taken down by Calais Campbell and O'Brien Schofield following an incomplete pass. Kitna was down for several moments as the trainers looked at his right leg. He limped off the field and was replaced by backup Stephen McGee, who took one snap.
Kinta returned to finish the drive, pulling the Cowboys within 21-10 with the pass to Witten, but he was clearly in pain. McGee took over for the Cowboys' final first-half drive.
Kitna tried to warm up before the start of the second half but was unable to play.
"As a quarterback you got to be able to [use the lower body]," Kitna said. "Any of that movement hurts. We tried to do what we could to block the pain. We were hoping it was a hip pointer. It's more than that."
McGee, a second-year pro out of Texas A&M, played the entire second half. He finished 11-of-17 for 111 yards and a touchdown in his first career appearance.
Kitna and McGee are the only quarterbacks on the Cowboys' roster. Starter Tony Romo has been out since he suffered a broken collarbone on Oct. 25 and was placed on injured reserve Tuesday.
The Cowboys thought Kitna and McGee could get them through the rest of the season, but that might not be possible. Dallas would have to release a player to make room for a quarterback, even though it would be for just one game.
"McGee would be the first [quarterback], but you have to have somebody ready to go," owner/general manager Jerry Jones said about what would happen if Kitna couldn't play next week.
Last year, Romo played every snap for the first time in his career.