Tony Romo had back surgery and will miss Dallas' third straight season finale with the NFC East title and a playoff berth on the line.
Coach Jason Garrett said Romo underwent surgery Friday after consultation with doctors during the week following his injury in a win over Washington.
Kyle Orton will start for the Cowboys in the winner-take-all game against Philadelphia on Sunday night.
Romo lost the past two winner-take-all finales to the New York Giants two years ago and Washington last season. He also lost to the Eagles in the same situation in 2008.
Philadelphia (9-6) is trying to complete a worst-to-first turnaround from a 4-12 season under first-year coach Chip Kelly. The Cowboys (8-7) want to end a three-year playoff drought.