Implant materials for knee and hip joint replacement: A review from the tribological perspective

Abstract

The hip and knee joints work under boundary/mixed lubrication during sleep and rest which causes starved lubrication by the natural lubricant synovial fluid and with the passage of time leads to arthritis resulting from the wear of joints due to starved lubrication. The excessive wear leads to loosening of joint needing total joint replacement. The current materials used in total knee replacement and total hip replacement are presented in this paper. Biomedical implants are gaining increasing attention nowadays to improve the working lifespan of joint replacements like hip and knee. Researchers are focussing on developing biocompatible materials with improved wear resistance for joint replacements. Various biocompatible metals and polymers have been used for knee & hip joints which are discussed in this paper. The investigations on self-lubricating biocompatible coatings on metals and alloys are the current focus of research. In this paper, a broad review of the materials used for total joint prosthetics is presented and the current trends of the joint replacement technology are discussed besides highlighting the various issues and challenges.