Two little hangnails quickly led to emergency surgery for rocker Ozzy Osbourne, according to his wife Sharon.

The former Black Sabbath frontman had to postpone his Saturday night (06Oct18) concert in Mountain View, California after checking into Los Angeles' Cedars-Sinai Medical Center with an infection that required doctors' immediate attention, and he was still in hospital on Monday.

The turn of events shocked Ozzy's manager wife Sharon as the health emergency developed from what had started as minor injuries on his right hand.

"He had a little cut on his thumb and you know when you like, pull the side of your nail? He just left it and then he hit it on a door and it started to get bigger and bigger," Sharon explained on her daytime show The Talk on Monday, revealing the "same thing" happened to his middle finger, which also began to swell.

"On Saturday morning, we took him into the emergency room and what had happened from a tiny thing on the side of his nail, it had turned into two different infections in his hand," she shared, "and he had to have two operations, where they cut the side of his thumb and his (middle) finger... to get rid of the infection."

"From something which you would think is absolutely nothing, he's still in hospital today. It's unbelievable," she marvelled. "He's on antibiotic drips, two different kinds. He's just stuck there... eating ice cream."

Ozzy has now cancelled two more dates on his No More Tours 2 tour in Chula Vista, California on Tuesday (09Oct18) and the Hollywood Bowl in Los Angeles on Thursday (11Oct18), but he will be back to perform for disappointed fans - the Hollywood Bowl and Chula Vista concerts will now take place on 15 and 18 October, respectively, and the Mountain View show at Shoreline Amphitheatre has been moved to 20 October (18).

Ozzy is aiming to be back in action on Saturday (13Oct18) for his show at the MGM Grand Garden Arena in Las Vegas.