Orthopaedic wires and cables and methods of making same

摘要

Orthopaedic wires, cables, and methods of making them are based on the discovery that, in clinical orthopaedic applications, material toughness and fatigue strength are as important or more important than ultimate tensile strength. The wires and cables of the invention have a tensile strength lower than 280 ksi, but higher than 175 ksi. The presently preferred wires and cables have a tensile strength of 210-240 ksi. The fatigue strength of the wires and cables of the invention is between six and ten times that of other high strength cables used in orthopaedic applications. One method of making the wires and cables includes annealing high tensile strength wire or cable to reduce its tensile strength and thereby increase its fatigue strength. Another method is to cold work fully annealed wire or cable to the extent of decreasing its cross section by approximately 18%. Presently preferred wires and cables according to the invention are made from chromium-cobalt alloy, preferably wrought VITALLIUM (registered trademark) alloy.