Knee surgery sidelines Dortmund's Bender
The Germany international twisted his knee on Wednesday and subsequently went under the knife on Friday.
Dortmund announced that the surgery was a success and that a recovery period of approximately four weeks is required.
"Borussia Dortmund's Sven Bender twisted his knee on Wednesday," read a statement on Dortmund's official website.
"The midfielder was successfully operated on today [Friday].
"Dortmund team doctor Markus Braun expects a downtime of about four weeks."
Bender has made 13 league appearances for the Bundesliga strugglers this term.
Jurgen Klopp's men entered the mid-season break in the relegation zone having won just four of their 17 league matches.
Dortmund resume their campaign at Bayer Leverkusen on January 31.