Osbourne as the Hunchback of Irvine Meadows

Putting Ozzy Osbourne in front of a theater full of teen-agers is like putting Quasimodo in charge of Romper Room. But far from recoiling in horror, the tots go delirious with glee.

Osbourne’s show at Irvine Meadows on Thursday was both engaging and pathetic. Engaging because of the energy and single-mindedness with which the heavy-metal gnome set about giving 10,000 or more kids a good time. Pathetic because of the British singer’s obvious need to have that approval--a need that sidetracked his 90-minute set and deprived it of meaning and focus as he carried on constantly as cheerleader and rabble-rouser.

Like Quasimodo, Osbourne at his best has cried out memorably for sanctuary, in songs that express horror at the threat of nuclear war, or confess Osbourne’s own sense of inner confusion.

Osbourne played some of those songs during his set, including “Iron Man,” “Paranoid,” and “War Pigs,” three enduring grunge-rock songs from his Black Sabbath days. The problem was that but none of them meant a thing--at least not as Osbourne presented them Thursday. Taking off shoes and socks and tossing them into the crowd may be endearing, but what did it have to do with “War Pigs”? That was the pattern throughout the show: Ham it up, be Ozzy. Don’t worry if the story gets lost or ignored.

The music had force, with former Sabbath bassist Geezer Butler and drummer Randy Castillo providing a driving foundation and guitarist Zakk Wylde doing a Ted Nugent gonzo-rock imitation.

Second-billed White Lion’s set could have used a lot more roar from singer Mike Tramp, an extremely limited vocalist whose husky but bodiless voice seemed incapable of sustaining a note. Vito Bratta, a flashy, talented guitarist, gave the 50-minute set its bite.

Vixen, an all-female band, turned in an opening set that was energetic, unpretentious and well-played, although it stuck firmly to unimaginative pop-metal formulas.