How does reactive hyperemia over a bony prominence occur?

Turning a patient off an affected site

(a) heat causes vasodilation that increases circulation to the area and results in erythema, not reactive hyperemia. (b) compressed skin appears pale because circulation to the area is impaired. When pressure is relieved, the skin takes on a bright red flush as extra blood flows to the area to compensate for the period of impeded blood flow. (c) effleurage, light stroking of the skin, simulates the peripheral nerves and should not change skin coloration. (d) The can cause a friction burn or a shearing force that can injure blood vessels and tissues.