PHOENIX _ Ameer Abdullah isn't the only Detroit Lions running back returning from season-ending surgery.
Theo Riddick, who missed the final month of the regular season last year, had surgery on both of his wrists, which prompted his season-ending trip to injured reserve, two people familiar with the procedure told the Free Press. They would not go on record because they are not authorized to talk about it publicly.
The Lions did not announce Riddick's surgery at the time he went on IR, and Riddick declined comment on his injury after the season, while he was wearing a cast on his left wrist.
Riddick is expected to be a full participant in organized team activities later this spring, but his injury is another consideration for a Lions team looking at possibly upgrading its backfield this offseason.
Abdullah played in parts of two games last year before undergoing season-ending foot surgery _ he also underwent surgery to repair a torn labrum in his shoulder after his rookie season of 2015 _ and Riddick missed seven games total last year, including the playoffs, with wrist and ankle injuries.
The Lions finished 30th in the NFL in rushing last season, and general manager Bob Quinn has been open about his desire to fix the running game this spring.
Already, the Lions signed two of the best offensive linemen available in free agency in right tackle Rick Wagner and right guard T.J. Lang, and they could look to add a running back high in April's draft or sign an aging veteran as insurance.
As many as four running backs could go in the first round of the draft, with LSU's Leonard Fournette, Stanford's Christian McCaffrey and Florida State's Dalvin Cook considered the top prospects at the position.
Oklahoma's Joe Mixon is a wild-card, a potential first-round talent who was caught on video punching a woman and is completely off some teams' draft boards, and the Lions have spent plenty of time studying potential mid-round backs in recent weeks.
Lions running backs coach David Walker has led pro-day running back workouts at Oklahoma (Mixon and Samaje Perine), Toledo (Kareem Hunt), Pittsburgh (James Conner) and Wisconsin (Corey Clement, Dare Ogunbowale), among other schools.
In the veteran free-agent market, Adrian Peterson, Jamaal Charles and LeGarrette Blount are among the players still available.
For now, Abdullah remains the Lions' No. 1 running back, with Riddick the top pass-catching option out of the backfield. Riddick, who tied for the NFL lead among running backs with 80 catches in 2015 and led the Lions with 357 yards rushing last year, signed a three-year, $11.5 million extension last September.
Zach Zenner, who shined when finally given an opportunity late in the season, and Dwayne Washington also return in the Lions backfield.
