Matthew Stafford's doctors told the Detroit Lions quarterback that the broken bones in his back are a "six-week injury," ESPN's Adam Schefter reported Sunday.
"This doesn't mean Stafford will be sidelined six games, but it does provide a glimpse into the severity of the injury that he has played through," Schefter wrote.
Stafford is missing his second straight game Sunday against the visiting Dallas Cowboys. The Lions have not provided a timetable for his return.
Before sitting out last week's game in Chicago, Stafford had started 136 consecutive games -- the sixth-longest streak for a quarterback in NFL history.
Backup Jeff Driskel started against the Bears and was back under center Sunday against the Cowboys.
The 31-year-old Stafford has completed 64.3 percent of his passes for 2,499 yards, 19 touchdowns and five interceptions in eight games this season.
--Field Level Media