A 75-year-old woman and her 9-year-old granddaughter were in a car accident in which both sustained trauma to the chest while seated next to each other. X-ray images showed that the grandmother had...

A 75-year-old woman and her 9-year-old granddaughter were in a car accident in which both sustained trauma to the chest while seated next to each other. X-ray images showed that the grandmother had several fractured ribs, but her granddaughter had none. Explain these different findings.

At work, a box fell from a shelf onto Ella’s acromial region. In the emergency room, the physician felt that the head of her humerus had moved into the axilla. What had happened to Ella?