Joe Freeman of the Oregonian reports (via blog):

Just when you think it can’t get any worse for this injury-depleted Trail Blazers team, it suffers yet another significant setback Tuesday night in Dallas.

In the first quarter of their game against the Dallas Mavericks, Joel Przybilla landed awkwardly and violently on his right leg beneath the basket and had to be helped away from the American Airlines Center court by two teammates.

Shortly after halftime, the team announced that Pryzbilla had suffered a ruptured right patella tendon and patella dislocation. He is out indefinitely.