How long would you stay in the hospital for a head injury, a broken forearm, and a broken shin from bike accident?

Depends: The answer entirely depends on the severity of each of these injuries. A minor head injury with brief loss of consciousness or simple hairline fractures could be assessed and treated in the emergency room. Severe head injury with brain swelling might require days to weeks in the hospital, while complex fractures would require surgery and several days or more in the hospital.