Osbourne, 55, was "stable and comfortable" after emergency surgery that restored the flow to a blood vessel damaged in Monday's accident, said Dr. Dick Jack, the medical director at Wexham Park Hospital in Slough, west of London.
"When he was admitted, he had a fractured left collarbone, he had some damage to the blood vessel that is underneath it, he had eight fractured ribs on the left side and, in addition to that, an entirely stable fracture to one of the vertebrae in his neck," Jack said. "This is not a major problem."
He said doctors planned to reassess Osbourne's condition later Tuesday morning.
Osbourne sustained the injuries while riding a quad bike, or all-terrain vehicle, on his Buckinghamshire property in southern England.
His U.S.-based publicist Cindy Guagenti said the singer was taking a day off from promoting the British release of "Changes," a duet with his daughter, Kelly, when the accident occurred. The song is a likely contender for the Christmas No. 1 spot in Britain's singles charts — a hotly disputed distinction that fuels huge speculation in the British media.
Osbourne's publicists in Britain could not immediately be reached for comment about how the accident occurred and whether it might affect the record's chances of success.
Ozzy Osbourne, who grew up in Birmingham, central England, rose to stardom with heavy metal group Black Sabbath in the 1970s before launching a solo career.
His fame grew hugely after he became the subject of hit reality-TV series "The Osbournes." The MTV show featuring the rocker, wife Sharon and their children Kelly and Jack, started production about a month ago on its third season, scheduled to begin Jan. 13.
It was not immediately known how Monday's accident would affect production or how or whether it might be included in the series, an MTV spokeswoman said.
Osbourne last month postponed a planned European tour until next year because of the effects of medication he's taking to treat tremors.
On Saturday, a story on the Los Angeles Times Web site reported Osbourne's claim that he was overprescribed a variety of powerful anti-psychotic and tranquilizing drugs by a Beverly Hills physician.
Osbourne said he developed a 42-pill per day habit that accounted for his odd behavior on the hit MTV show, including scenes in which Osbourne was seen mumbling, falling and appearing disoriented.
The rocker blamed a Beverly Hills physician, David Kipper, for overprescribing the drugs. Kipper has been investigated for overprescribing drugs to other celebrity patients.
On Monday, actor-director Danny DeVito issued a statement in support of Kipper. DeVito said he and his wife, actress Rhea Perlman, and other family members have relied on Kipper for medical care for more than 20 years.
"He has always been, to us, the most honest, caring, selfless, responsible doctor we have ever had," DeVito said in the statement.
Calls to Kipper's office Monday were not returned.
Earlier this month, Osbourne told a British newspaper he'd been sexually molested as a child and suffered emotional effects from the abuse long into adulthood.
By Lynn Elber