Schild, one victory short of the record of the 34 World Cup slalom wins held by Swiss Vreni Schneider, crashed badly in her warm-up practice in Sweden on Thursday and tore ligaments in her right knee.
The injury was confirmed by doctors who checked the knee in Innsbruck, OSV said.
"Marlies will now undergo surgery in Innsbruck and will need at least three weeks before starting intensive rehab," OSV added.
The world championships take place in the Austrian resort of Schladming between February 4 and 17.
Schild had endured a disappointing start to the season, crashing out of contention in Levi before finishing second to compatriot Kathrin Zettel in Aspen last month.
The 31-year-old missed the entire 2008-2009 season after breaking her shin in training in October 2008.
- Sports & Recreation