"We'll probably know more in a few days," Flyers general manager Paul Holmgren, according to the Philadelphia Inquirer. Holmgren said he'd never heard of such an injury.
According to the newspaper, Coburn wasn't sure how he injured himself in the Flyers' 2-0 loss to the Rangers. Lasse Kukkonen replaced Coburn in the lineup for Sunday's 4-3 loss to Pittsburgh.
"You don't want to see anyone go down, especially like that, a guy rushed to the hospital," Kukkonen said, according to the Inquirer. "I heard he is OK. I talked to him last night, and he is feeling better."
Coburn, who turns 23 on Feb. 27, has four goals and 20 assists in 54 games this season.