It has been reported that Kimi Raikkonen will have back surgery to alleviate his long term back injury sustained in a 2001 test accident at Magney Cours.
The Lotus F1 Team has yet to confirm anything for certain, but it is widely accepted that 2012 GP2 Drivers Champion Davide Valsecchi will replace Raikkonen for the last two races in Austin and Interlagos.
It’s a outside bet that Nico Hulkenberg will replace Raikkonen as the deal would have to be completed quickly. Then the technical challenges of getting him a seat made (3 days) and him pedal positions and getting to know his steering wheel. All that is about a week or so. So all in, I doubt Hulkenberg will take the seat, hence why Valsecchi will take the seat if car 7.
Valsecchi will become the first Italian in F1 since Jarno Trulli left in 2011 at the end of the pre season test at Jerez. He was replaced at Team Lotus (Caterham) by Vitaly Petrov then.