Robert Kubica's Formula 1 career is under threat after his right hand was partially severed in a high-speed rally crash in Italy on Sunday.
He also suffered arm and leg fractures after his car hit a church wall.
Kubica who drives for the British-based Renault F1 team, had seven hours of surgery after he was airlifted to a hospital near Genoa.
The 26-year-old Pole looks at least likely to miss the entire 2011 season, which starts in Bahrain on 13 March.
Initial reports suggested he was in danger of losing his hand, although those fears were later played down.
However, Professor Mario Igor Rossello, a specialist surgeon involved in the lengthy operation, said that it was too early to accurately assess the long-term implications of his injuries.
Rossello told reporters he was "moderately satisfied" with the operation to rebuild the hand, but said that it would be several days before doctors could determine whether the hand would be "able to return to full function".
He added: "The danger is, in five-seven days you can have vascular problems, and we could do surgery again to solve these problems."
When asked what the best prognosis for recovery would be, Rossello replied: "One year. One year is the best provision."
The doctor said he expected the driver to recover "enough functionality for him to resume his activity."
KUBICA STATS & FACTS
Robert Kubica
Team: Renault
Former team: BMW Sauber
Team-mate
Vitaly Petrov
Nationality: Polish
Born: 7/12/1984, Krakow
Grand Prix debut: Hungary 2006
He was operated on after reportedly being trapped in his car for more than an hour while specialist cutting equipment arrived in Peitra Ligure.
Kubica also needed surgery in 2003 after a serious road accident as a passenger that left him with titanium bolts in his arm.
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