The Real Madrid loanee required surgery to stitch a fractured shin bone for the second time in the space of six months.
"Unfortunately, I've suffered a relapse of my shin injury," the Spain Under-21 midfielder wrote on Twitter.
"I have not long come out of the operating theatre and everything has gone smoothly. Now I have to be patient and start my recovery so I can start playing football again soon. Thank you very much to everyone for the well wishes and messages of support."
Medran has made seven appearances for Getafe since joining on a season-long loan from Real, where he has so far played five times and scored one goal.