Metal-on-metal artificial hip devices have been available for more than twenty years. Years ago, product manufacturers thought that metals like titanium, cobalt, and chromium used in the construction of artificial hips would last a lot longer than the regular shelf life of other artificial hips using plastics and ceramic materials, particularly for athletes and active people. Unfortunately, those metals have caused many problems, like metallosis, which happens when metal particles grind away from the artificial hip and leach into the bloodstream and surrounding tissue, causing pseudotumors, high levels of metal in the blood, and other problems.
Various manufacturers developed different metal-on-metal artificial hips. In most cases, it did not go well for the thousands of patients who had hip replacement surgery. Hundreds of thousands of those patients have subsequently become plaintiffs in litigation against all those companies.