Noah had been playing through a shoulder injury first suffered in January, the team said. An MRI at that time concluded that he'd suffered a rotator cuff injury.
Noah continued to play through the injury, but he was sidelined for several weeks in early February with various injuries, including a knee ailment that required arthroscopic surgery.
In April, Noah underwent another MRI of his shoulder that revealed no significant healing, the Knicks said. Team doctors have recommended surgery, but no final determination has been made at this point.
If Noah undergoes surgery, the expectation is that he'd be sidelined for at least four months, though league sources cautioned on Tuesday night that it was too early in the process to determine a specific rehab timeline.
Noah is currently serving a 20-game suspension for violating the league's anti-drug policy and will be sidelined for the first eight games of the 2017-18 season due to the punishment.
The shoulder injury is the latest health setback for Noah this season, his first with the Knicks. He played in just 46 games in 2016-17 due to various injuries, including the knee ailment and a hamstring issue.
He has not played since Feb. 4, though he was cleared by the NBA's independent medical expert late last month, which allowed Noah to begin his suspension.
Noah tested positive for an over-the-counter supplement -- selective androgen receptor modulator LGD-4033 -- that is banned under the NBA's current collective bargaining agreement. He said that he'd taken the supplement while rehabbing from an injury.
Noah's potential shoulder surgery is not expected to impact his ability to serve the final 8 games of his 20-game suspension next season. If Noah undergoes surgery, then the NBA will work with the team and determine what steps need to be taken to clear him in order to continue serving the suspension. More than likely, the NBA's independent doctor would clear Noah if the health of his shoulder was still in question leading into the season.
The shoulder injury concludes an underwhelming season for Noah, whom the Knicks signed to a four-year, $72 million contract over the summer. Team president Phil Jackson hoped Noah could be a defensive anchor for the club, but the Knicks struggled on that end of the floor. Noah performed below expectations -- his own and the team's -- and New York stumbled through another 50-plus-loss campaign.
With Noah sidelined due to suspension for the beginning of the season -- and possibly due to shoulder surgery --Kristaps Porzingis or Willy Hernangomez will likely start the year at center for New York in 2017-18.