According to Mike O’Hara, who writes for the Lions‘ team site, said during a recent episode of his podcast with WJR’s Ken Brown (via MLive.com). “Broken bones in his back.”

NFL.com’s Ian Rapoport described the injury as “tiny fractures in his back.”

Stafford was listed as questionable in Weeks 14-16 but started all three games, as well as the regular-season finale. Over that stretch, the Lions went 2-2 and Stafford threw three touchdowns with no interceptions.

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