"I got up this morning prepared to race, but after a few warm-up runs, I wasn't feeling confident on my skis," Vonn said.

"Normally I can fight through injuries, but head injuries are different. You can't just grit your teeth and go.

"I'll go through my normal routine tomorrow (Saturday) morning in Zwiesel and if things feel more normal, I'm hoping to start the giant slalom."

Vonn crashed in giant slalom training on Wednesday.

A video posted on her Facebook page showed the American over-compensate on a left-turning gate, bucking with split skis and landing heavily on her back before sliding to a halt.

She said that the spill had not left her with any serious injury in a major scare ahead of the last World Cup outing before the February 8-20 World Championships in Garmisch-Partenkirchen.