Margera was hospitalized and underwent a hernia operation after participating in a 100-foot kayak drop Wednesday, the "Jackass" star tweeted.
Margera, 32, published a picture of himself in his hospital bed with the note, "Hernia operation after 100ft kayak drop."
Earlier, the pro skater wrote, "Just did a 100ft tandem kayak jump with pro kayaker Steve Fisher in Oregon!" He also posted a photo of the jump.
Margera was scheduled to appear at an art show in his native West Chester, Penn. on Friday night, featuring work by himself and local artist John Hannafin. However, the hospitalization forced him to cancel the appearance.
Margera recently signed on for MTV2's "Hip Hop Squares," which premiered last week.
