Ryans was carted off the field in the fourth quarter after fumbling the ball following an interception. The person spoke on condition of anonymity because the Eagles didn't release details of the injury.
Ryans is expected to miss the rest of the season. He suffered the same injury on his left leg on the same field in 2010 when he played for Houston.
The Eagles also lost quarterback Nick Foles to a possible shoulder injury. Foles wore a sling on his left arm after the game. Mark Sanchez filled in and led the Eagles to a win in his first game action since 2012.
Foles was taken for X-rays after being sacked twice in three plays by Whitney Mercilus in the first quarter.
Joseph was led off the field after making a hard hit on Darren Sproles and missed the rest of the game with a concussion. Jackson left with a knee injury.
In other injury news:
-Dolphins running back Lamar Miller left his team's win over San Diego in the second half with an injury. He said he suffered a stinger that wasn't serious. And Chargers center Rich Ohrnberger (ribs) and defensive tackle Sean Lissemore (quad) were sidelined in the second half.
-Bengals right tackle Andre Smith sprained his left ankle in the first half against Jacksonville, returned before halftime but sat out the second half. And Jaguars guard Brandon Linder (shoulder), Evans (shoulder) and linebacker Jeremiah George (sprained ankle) left the game and didn't return.
AP Pro Football Writer Rob Maaddi in Philadelphia contributed to this report.
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