Williamson will be re-evaluated in 4-6 weeks once further imaging on the foot can occur.
Earlier this week, he traveled to Los Angeles to meet with Dr. Richard Ferkel of Southern California Orthopedic Institute. Ferkel, who along with Pelicans team doctors performed the initial surgery on Williamson's fractured right foot, gave him the biologic injection on Wednesday.
"I don't necessarily want to speak for him but I have spoken to him, but it's just been frustrating for everyone," Pelicans coach Willie Green said after practice on Thursday.
"It's been frustrating for him, his family. We're continuing to navigate adversity. We want to be encouraging and hopeful. It's just something that he's dealing with and we're all dealing with as an organization. We just have to try and keep getting through it. But it's been tough."
The team says Williamson will be limited to low-impact, partial weight-bearing activities for an extended period.
Williamson, who broke the foot during offseason workouts, has yet to play in an NBA game this season.
In his absence, the Pelicans are 9-21 and are coming off a wild buzzer-beating victory on Wednesday night against Oklahoma City.