Teams were conducting pre-season tests at Portimao where Espargaro suffered from fibrosis over the weekend which affected his test schedule.
"Following fatigue in his right forearm, which occurred during the recent MotoGP tests at Portimao... Aleix Espargaro underwent a series of tests between yesterday and today at the Dexeus University Clinic in Barcelona," the team said.
"The checks revealed a fibrosis in the muscle for which a surgical operation was necessary."
Aprilia said he would recover from the "cleaning operation" in time for the race on the weekend of March 24-26.
Espargaro, who finished fourth in the riders' standings last year, later posted a picture of his arm in a sling with the caption: "Surgery done! I had a lot of pressure in my forearm, so everything is released and ready to race!"
Follow the season-opening MotoGP in the Algarve on Flashscore.
