Nelson, 29, has not missed a game since 2012 but had knee surgery in August 2013.
McCarthy said the hip issue is something that was "kind of hindering him" after the Pro Bowl but that it's "nothing serious."
"He had some postseason work done," McCarthy said, according to ESPN Wisconsin. "He'll be fine in a couple weeks. I've seen him. [I think] it's 6 to 8 weeks [recovery time], but really he should answer that. But it's nothing serious."
Nelson caught a team-high 98 passes for 1,519 yards and 13 touchdowns last season, his sixth with the Packers.