It's unknown how Smith sustained the injury, but it doesn't seem too severe. Smith will apparently be kept on the active roster while he recovers, so there doesn't appear to be any long-term implications.
Dave Fipp's special teams unit has bolstered the team in 2014, with four touchdowns coming from the group. Smith has one of the team's two blocked punts for touchdowns, after Trey Burton blocked Andy Lee's punt in the end zone on September 28. It was Smith's first touchdown with the Eagles; he hadn't scored since Week 17 in 2012, on a four-yard rushing touchdown with the Bills.
With Smith out, James Casey will now fill in as the seldom-used 'emergency quarterback'.
Follow Justin Henry on Twitter