The idea was that the reigning Olympic champion in slalom would return to the World Cup soon.
Now it is unclear when a comeback is to be expected.
"Petra is still experiencing discomfort in her knee, which means she cannot fully load it in skiing. Extensive examinations revealed cartilage damage, which requires further specialized care," her team writes in a press release.
Vlhova crashed on home ground in the World Cup in Slovakia and badly injured one knee.
"I expect that we will know more about her ability to handle full load by the end of December," says her coach Mauro Pini.
Vlhova and American Mikaela Shiffrin have dominated in slalom in recent seasons. Shiffrin injured herself in Killington two weeks ago and is out for an indefinite period.
The World Championship will take place in Saalbach, Austria, in February.
