Iron Lynx Ferrari driver Davide Rigon was also hospitalised although it was quickly confirmed neither he nor Aitken, who had been driving an Emil Frey Racing Lamborghini, had sustained life-threatening injuries.
"First of all, thank you to everyone who has supported me in the last 16 hours or so, from the marshals, medical staff trackside and at the hospital, my wonderful team, fellow drivers and all of you sending messages," wrote Aitken on social media.
"All things considered I feel fine, and quite lucky.
"I’ve broken my collarbone, and fractured a vertebra but it’s stable, fortunately. The aim now is to get back to the UK and start to recover as best as possible and be back in the car soon. I’m sure with the people around me I’ll manage it just fine!
"Finally, a thank you to Lamborghini Squadra Corse for building a damn strong chassis."