"I tore my labrum before the season started and played the year with it," Reid tweeted. "It was painful at times but still an easy decision to continue to play! I love my team, I love my teammates, I love this city, and I love to play. I will do anything to help us win!"
He added: "Honestly I didn't think I'd make it [through] the entire season. I prayed before every game and I thank god for watching over me and allowing [me] to play the entire season without fear."
Reid, a third-round pick in 2018, will have surgery and said he is looking forward to "the road to recovery to dominate next season."
Reid only missed one game in 2019 and finished with 78 tackles, two interceptions and a fumble recovery.
Reid had wrist surgery at the beginning of last offseason.