On 16 March 2009, Richardson sustained a head injury when she fell while taking a beginner skiing lesson at the Mont Tremblant Resort in Quebec, Canada about 80 miles (130 km) from Montreal. The injury was followed by a lucid interval, when Richardson seemed to be fine and was able to talk and act normally. Paramedics and an ambulance which initially responded to the accident were told they were not needed and left. Refusing medical attention twice, she returned to her hotel room and about three hours later was taken to a local hospital in Sainte-Agathe-des-Monts after complaining of a headache. She was transferred from there by ambulance to Hôpital du Sacré-Cœur, Montreal, in critical condition and was admitted about seven hours after the fall. The following day she was flown to Lenox Hill Hospital in New York City, where she died on 18 March at the age of 45.
An autopsy conducted by the New York City Medical Examiners Office on 19 March revealed the cause of death was an "epidural hematoma due to blunt impact to the head", and her death was ruled an accident.Epidural or extradural hematoma (haematoma) is a type of traumatic brain injury (TBI) in which a buildup of blood occurs between the dura mater (the tough outer membrane of the central nervous system) and the skull. The dura mater also covers the spine, so epidural bleeds may also occur in the spinal column. Often due to trauma, the condition is potentially deadly because the buildup of blood may increase pressure in the intracranial space, compress delicate brain tissue, and cause brain shift. The condition is present in one to three percent of head injuries. Between 15 and 20% of epidural hematomas are fatal.