Kubica under knife for 9 hours
Kubica was badly injured in a crash during the Ronde di Andora rally in Liguria last Sunday.
He was airlifted to hospital and underwent seven hours of surgery to save the functionality of his hand.
And a new operation to rebuild his foot, shoulder and the inner part of his elbow on Friday lasted even longer.
"We finished the second surgical intervention on his upper arm, which was already compromised in a previous accident," said orthopedic surgeon Dr Francesco Lanza.
"We gave him a bone graft and inserted a plate. We operated on the inner part of the upper arm but we still have to operate on the outer part."
Kubica will return to intensive care for two days.
Dr Igor Rossello, who operated on the Pole's hand, said it had shown no bad reaction to the second operation.
Earlier on Friday, Kubica gave his first interview since the accident, speaking to La Gazzetta dello Sport.
"The fingers work, I can feel them. My arm too. But they still need to operate on me and only after that will we know," he said.
"I don't have much pain but I'm sedated. After the last operation, the countdown to my return to the track will begin."
The Lotus Renault GP driver was racing a Skoda Fabia in the Italian rally when he lost control at high speed on a bend, crashing into a guard rail and ending up in a church wall.
His co-driver, Jacub Gerber, emerged unhurt.
Meanwhile, Polish church leaders are hoping that a drop of blood belonging to the late Pope John Paul II will put Kubica on the road to recovery.
Kubica is to receive a drop of the late pontiff's blood and a strip of fabric from one of his liturgical robes, Poland's Cardinal Stanislaw Dziwisz told the commercial TVN24 news channel in Warsaw.
"John Paul II was a sportsman himself, he loved sport as a young man," Dziwisz said of the late pontiff, whom the Vatican has put on the fast track to sainthood.