Vonn, who nearly wiped out in the final stretch but recovered to complete it in 1:21.49, was already out of medal contention by then. She was a favorite coming in because she is especially adept at gliding, which this course required.
Ledecka’s run pushed Vonn down to a tie for sixth, 0.38 behind Ledecka.
The final stretch cost Vonn the chance at the podium.
Vonn completed the first three-quarters of the run in 1:03.8 compared with the 1:03.95 that Tina Weirather of Liechtenstein, who won bronze, later posted. Then Vonn completed the final stretch of the race in 17.69, while Weirather completed it in 17.27.
During that last stretch Vonn lost her balance as the course turned sharply left. Her right ski slipped from under her center of gravity, and her left hip was inches from the snow. Vonn recovered and finished, but precious fractions of a second were lost.
In a few days, Ledecka will gain another distinction. She will become the first person to compete in skiing and snowboarding at the same Games when she enters the snowboard giant slalom.