As soon as she got home, the phone was ringing. She answered and the vet told her she was in danger and to get out of the house. (He didn't tell her the dog was choking on human fingers). The vet had called the police. They later found a burglar in her upstairs closet, shaking with fear, bleeding to death, with three missing fingers!
For other urban legends like this one, I recommend "The Choking Doberman" by Brunvand, currently in print and available through Amazon. I believe I got my copy around 1988.