An adjustable cranioplasty plate assembly is provided for use following a craniectomy. The assembly includes a ring which is attached to the skull around the skull opening and a plate adjustably mounted to the ring. The plate is moveable between a raised position spaced above the ring and a lower position substantially flush with the ring. The plurality of extendable and retractable struts extends between the ring and the plate to provide the plate adjustability. The plurality of stay cables extending between the ring and the plate provide lateral stability in the raised position. The assembly replaces the native bone and eliminates the need for subsequent cranioplasty surgery. In one embodiment, the plate includes a rigid central portion, three rigid mounting tabs, and a plurality of malleable tapered perimeter petals which provide a smooth interface between the plate and the skull of the patient.