Shumpert sat out the Knicks' loss to the New Jersey Nets Monday because of the injury.
He had been playing through pain in his knee, but it became too much to bear after the Knicks' win Sunday over the defending champion Dallas Mavericks.
He is officially listed as day to day. In an interview on ESPN 1050 New York's "The Michael Kay Show," Mike D'Antoni said Shumpert will be out until after the All-Star break.
Shumpert's status for Wednesday's game against the Atlanta Hawks is unclear. The Knicks (16-17) missed his perimeter defense against the Nets, who hit 15 of their 31 3-point attempts. Deron Williams had 38 points, making eight 3-pointers.
Knicks point guard Jeremy Lin, whose recent rise from end-of-the-bench player to starter has gained widespread attention, will participate in the Rising Stars Challenge. He was supposed to assist Shumpert in the dunk contest.
Carmelo Anthony will start at forward for the Eastern Conference in Sunday's All-Star Game in Orlando.
Ian Begley is a regular contributor to ESPNNewYork.com