The 22-year-old moved to Camp Nou from Borussia Monchengladbach in May and will complete with Claudio Bravo and Jordi Masip to be Barca's first choice under head coach Luis Enrique.
However, the Germany's international's pre-season preparations were disrupted on Monday, with the Catalan club announcing he was set for tests on a back complaint.
Medical examinations have confirmed the need for Ter Stegen to complete an individual training programme this week, although Barca have not confirmed whether he will miss the start of the season.
A Barca statement read: "After tests this morning at the club, the FC Barcelona medical services have confirmed the back injury suffered in training on Monday by Marc-Andre ter Stegen.
"Ter Stegen will be given specific recovery work over the next few training sessions."
Barca get their La Liga campaign under way at home to Elche on August 24.
