The 20-year-old singer was appearing in Dreamboats And Petticoats at the Malvern Theatre in Malvern, Worcestershire when scenery fell from behind him and hit his head.
Bruton was assisted by co-stars and first-aiders while show producers waited for an ambulance to arrive. Following a 40 minute delay, the production continued with an understudy replacing the star in the lead role of Bobby.
An onlooker told The Daily Telegraph: "It looked pretty painful the way he hit the stage like a sack of potatoes. We were all on the edge of our seats hoping that the accident wasn't too serious. The show was brilliant so it's such a shame that it had to be delayed while Scott was treated."
A West Midlands Ambulance service spokesman confirmed: "A male was treated for a head injury. He was drifting in and out of consciousness on his way to hospital."
Bruton, who competed in The X Factor's fifth series last year, was kept in hospital overnight for observation.