Anatomical knee endoprostheses – does a better-fit lead to better outcomes? A review article

Introduction. Total knee replacement is the most efficient method of treating end-stage osteoarthritis of the knee joint. The surgery aims to relieve patients of pain, restore range of motion and improve patients’ quality lives. Prostheses design is still being modified and improved through cooperation between orthopaedic surgeons and engineers. Some of the most modern solutions aimed to fit native patients’ anatomy as much as possible are anatomic knee systems. Materials and methods. The literature was reviewed, and articles related to the subject were researched. Therefore, publications including keywords such as total knee replacement, anatomic implants and morphometric implants were searched in the PubMed, Cochrane and Google Scholar databases. All data was selected and verified individually. Analysis and synthesis of studies were prepared separately. Results. Many studies describe the advantages of anatomic prostheses over standard prostheses. Anatomical prostheses have a broader range of available sizes, thus providing better coverage of the distal end of the femur and the proximal tibia, allowing for the resection of less bone tissue, which is beneficial in the event of a possible need for a future revision of the endoprosthesis, enabling better selection of the tibial element rotation by better matching to the tibial plateau, which affects the alignment and patellar movement, and the structure of the trochlear geometry that also affects the patellar movement and reduces the risk of trochlear dysplasia. Conclusions. Anatomical implants enable better alignment of the prosthesis elements and the native femoral and tibial bone. Using these models makes it possible to obtain a greater range of motion and, consequently, improved functional outcomes compared to non-anatomical ones. It also enables less bone resection and better radiological outcomes.