Complex sentence: In May 1963, she was struck by a car, and suffered a ruptured disc in her back, disrupting the momentum of her acting career as she spent a year recovering in a back brace.
Split into simpler sentences: In May 1963, she was struck by a car, and suffered a severe back injury (ruptured disc) that disrupted the momentum of her acting career. She spent a year recovering in a back brace.