Orthopaedic implants having self-lubricated articulating surfaces designed to reduce wear, corrosion, and ion leaching

Abstract

Mechanical devices such as prosthetic knees, hips, shoulders, fingers, elbows, wrists, ankles, fingers and spinal elements when implanted in the body and used as articulating elements are subjected to wear and corrosion. These prosthetic implants are usually fabricated in modular form from combinations of metallic materials such as stainless steels, Co—Cr—Mo alloys, and Ti—Al—V alloys; plastics such as ultra high molecular weight polyethylene (UHMWPE); and ceramics such as alumina and zirconia. As the articulating surfaces of these materials wear and corrode, products including plastic wear debris, metallic wear particles, and metallic ions will be released into the body, transported to and absorbed by bone, blood, the lymphatic tissue, and other organ systems. The polyethylene wear particles have been shown to produce long term bone loss and loosening of the implant. And, even very low concentrations of metallic wear particles and metallic ions are suspect in causing adverse toxic, inflammatory, and immunologic tissue reactions. This invention provides prosthetic implants having articulating surfaces that exhibit a reduced rate of release of wear debris and metal ions into the body and a method of producing such prosthetic implants.