Specifies a test method for determining under specific laboratory conditions the endurance properties of tibial trays used in knee-joint prostheses to support and secure the plastics articulating surface. Tibial trays which cover both the medial and the lateral platuaux of the tibia are applicable. Does not cover methods of examining and reporting the final condition of the test specimen; these may be subject of an agreement between the parties submitting the specimen for test and the test laboratory. Does not apply to tibial components manufactured solely from plastic materials.