Kim Shattuck, the singer, songwriter and guitarist whose work with the Muffs made her a raucous role model and put her in the vanguard of punk bands crashing into the mainstream in the 1990s, died on Wednesday at her home in Los Angeles. She was 56.

The cause was complications of amyotrophic lateral sclerosis, also known as Lou Gehrig’s disease, said Cary Baker, whose publicity firm, Conqueroo, represents Omnivore Records, the Muffs’ current record label.

Ms. Shattuck made music that combined bubble-gum melodies with roaring guitars. Her lyrics could be tender, but she concealed her vulnerability behind a sneering veneer. And she was widely acclaimed for having one of the greatest screams in rock ’n’ roll — a loud, exuberant yowl that sometimes expressed unfettered joy and sometimes just punctuated a chord change.

“She was always so cool and tough,” Billie Joe Armstrong of Green Day wrote on Instagram. Green Day regarded the Muffs so highly early in their career that it employed the same manager, label and producer.