Steelers LB Harrison has knee surgery

Pittsburgh Steelers linebacker James Harrison had arthroscopic surgery on his left knee Wednesday.

The surgery was performed to remove an impairment that has caused swelling since the spring.

Harrison, a five-time Pro Bowl selection, has yet to practice this summer and is on the physically unable to perform list.

The 34-year-old Harrison had 59 tackles and nine sacks in 11 games last season.