The High School Musical alum took to Instagram on Friday to share a photo of himself in a hospital bed after "shredding the gnar" just a little too hard.
"I tore my ACL shredding the gnar⛷ 😕 but all is good," Efron assured fans. "I opted for surgery so I can come back stronger than ever."
"Thank you to Dr. Kvitne and his team at Kerlan-Jobe Surgery Center. I’ll keep you updated as I heal and progress!" he added. "Thanks for all the love and positivity!"
The 31-year-old actor also shared several videos to his Instagram story of his "post op" plans: catching up on Game of Thrones and enjoying some frozen yogurt. "I'm going to watch Game of Thrones all the way through," he said, traveling to his couch on crutches.