During her first attempt, the athlete turned over and twice hit her head.
Demchenko is the silver medalist of the 2015/16 KM stage, which took place in Sochi.
At the moment, it occupies the 19th place in the overall standings of the KM, having in its asset 11 points.
Earlier it was reported that luger Roman Repilov won the sprint at the stage of KM in Lake Placid.