Justin Bieber cancelled his apperance on a Germany variety show after a contestant performing a stunt became injured. (Jacques Brinon/Associated Press)

Canadian pop star Justin Bieber cancelled his appearance on a popular German variety show after a stunt went horribly wrong on the weekend.

Saturday's episode of Wetten Dass?, a live-to-air show where daredevil contestants perform stunts, was cancelled after one competitor was struck by a car during an attempt to leap over several moving vehicles using spring-powered stilts.

The man crashed and lay motionless in front of the shocked studio audience, AOL Music reports. He was taken to hospital for emergency surgery. The contestant is reportedly in no danger of dying, but is showing signs of paralysis.

Bieber was scheduled to appear on Saturday's star-studded episode with British band Take That. The teenage singer tweeted that he didn't think it was appropriate to go on after the accident.

Which reality or stunt television shows go too far? Have you ever witnessed a terrible accident on television? Let us know in the comments below.