Cementless Hip Implants: History and Current Status of the Issue

Abstract

Background. Total hip arthroplasty is an effective type of surgery with excellent survival rates of modern implants. From the very beginning of the widespread introduction of total hip arthroplasty, the cement technique of components fixing prevailed. However, many researchers associated the development of osteolysis and the following loosening with the reaction to cement. The subsequent studies clarified the situation regarding the nature of osteolysis, but there remained the problem of insufficient stability of the cemented stems to withstand the penetration of polyethylene wear particles into the distal part of the stem with the development of loosening. An ideal endoprosthesis should ensure the normal hip biomechanics, joint painless functioning and improve the quality of life of the patient without the need for revision. The optimal results of cementless femoral stems functioning depend on the achievement of initial stability, osseointegration and equable transmission of tension onto the femur. There are many factors that influence osseointegration processes and the subsequent behavior of the implant. Understanding these factors is the key to choosing the optimal implant for a particular patient, taking into account the anatomical features of the femur.The purpose of this article is to discuss upon the literature review the application of cementless femoral components, the possible causes of failure and its prevention from the point of view of the evidence-based practice.Materials. The search was conducted in the PubMed, eLIBRARY databases and through the Web of Knowledge. Survival rates and prevalence of various implants in the structure of primary arthroplasty were estimated on the basis of annual reports of a number of national registries, as well as the hip arthroplasty registry of the Vreden National Medical Research Center of Traumatology and Orthopedics. Among the factors discussed are the properties of the components material, the form of the implants, surface properties, and the influence of the anatomical features of the femur. Additionally, the most used types of cementless femoral components were assessed.Conclusion. Cementless femoral components demonstrated the excellent long-term survival and functional results. The currently prevailing type of the prosthesis intimate attachment to the bone is the biological fixation, especially in groups of young patients. Future studies of cementless implants should necessarily take into account the patient’s age, level of activity, type of bone canal, the presence of deformities, and the friction pair used. This will make it possible to draw clearer conclusions in what clinical situation it is advisable to use the femoral components of a particular design.