Landa was taken down in a crash with just under 20km to go in the one-day race in the Basque Country, with his team confirming a fracture to his lumbar vertebra L1 after initial scans.
Since the crash last Saturday, a second fracture was discovered after an ultrasound on Wednesday, this time a non-displaced rib fracture on his right-hand side. Movistar said the recovery time wouldn't differ his initial injury, which they said would require two to three weeks of complete rest.
Landa has since begun a series of rehabilitation and therapy with the help of medical staff, but it is unclear if the 28-year-old will be able to take to the start line of the Vuelta alongside Nairo Quintana and Alejandro Valverde on August 25.
In a statement, Movistar said: "Under careful monitoring from the Telefónica-backed squad's medical staff and attentions from Javier Barrio, head doctor of the Deportivo Alavés football club, and traumatologist Mikel Sánchez, Landa is following various exercises of breathing mechanics and strengthening of the injured areas, in order to reduce inflammation, ease pain and ultimately fuse the fractures.
"Mikel remains in good spirits and optimistic towards his goal of recovering completely and as quickly as possible."
Landa will be keen to recover in time to take to the start of the Vuelta after a disappointing Tour de France in which he failed to challenge for the overall victory. The Spanish Grand Tour starts with a Prologue time trial on the opening day, with nine tough summit finishes scattered throughout the three-weeks of racing.
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