McAllister said later in the afternoon that everything appeared to be fine.
"Everything looks good in there," McAllister said in a text message to The Associated Press. "They just wanted to make sure."
McAllister had surgery to repair a torn anterior cruciate ligament in that knee last season. He was at practice, wearing his jersey and shorts, but only watched.
"He had some swelling so we backed off of him this morning," coach Sean Payton said. "Anytime you're coming off of a major surgery, you're optimistic and hopeful. It's just managing the injury."