Spaniard tweets to say his wound is not healing and there are complications
Contador crashed on a wet descent on the stage to Planche des Belles Filles where Vincenzo Nibali retook the yellow jersey. He initially tried to carry on, but abandoned soon after and was then diagnosed with a fractured tibia.
Since Contador left the race Tinkoff-Saxo have gone on to win two stages with Rafal Majka and Michael Rogers.
The Vuelta starts in Jerez de la Frontera, southern Spain on Saturday, August 23.