David Hasselhoff had to have emergency surgery after slicing his hand open in a bizarre shaving accident.The former 'Baywatch' star - who is in London filming an advertising campaign - severed a tendon in his hand and had to be rushed to St Thomas' Hospital by ambulance.The 53-year-old's spokeswoman, Judy Katz, told BANG Showbiz: "David had just finished working out in the gym at the hotel where he was staying. He was getting ready to shave and bent down but when he stood up David hit his head on a glass shelf and it shattered."Some of the glass got into his hand and cut it quite badly."She added: "The fact that he needs surgery to repair a tendon suggests it was quite a nasty cut, but he's in surgery right now, and hopefully not in too much pain."Hasselhoff is best known for his roles as Mitch Buchannon in 'Baywatch' and Michael Knight in the hit 80s TV show 'Knight Rider'.