Bush was placed on the season-ending injured reserve list Thursday.
Bush also had missed four games to recover from arthroscopic surgery for a knee injury suffered in an Oct. 19 game against the Carolina Panthers.
New Orleans (7-7) has been eliminated from the NFC playoff picture.
The Saints' first-round draft pick in 2006 out of Southern California finishes the 2008 season with two rushing touchdowns on 106 carries for 404 yards.
Bush demonstrated his versatility by scoring four touchdowns on 52 pass receptions for 440 yards, and scoring three times on punt returns.
"He wouldn't be put on IR if we had more than two weeks or three weeks left in the season," Coach Sean Payton told the Times-Picayune. "In other words, the news is fairly good, which is encouraging."