Unicompartmental knee arthroplasty Breaking the mold of the one-size-fits-all paradigm

This thesis explores how unicompartmental knee arthroplasty (UKA) can be optimized by moving beyond the traditional “one-size-fits-all” approach toward more individualized patient care for isolated compartment knee osteoarthritis. The first part of the thesis investigates factors influencing patient selection and implant choice. Using data from the Dutch Arthroplasty Register and prospective clinical studies, it evaluates age-related outcomes of cemented and cementless fixation, the
impact of psychological factors on patient-reported outcomes, and the influence of extra-articular tibial deformities on clinical results. Together, these studies provide evidence to refine indications for UKA and improve preoperative decision-making. The second part focuses on postoperative function, particularly return to sport. Systematic reviews compare UKA with total knee arthroplasty and other surgical treatments, demonstrating the advantages of UKA for restoring higher levels of physical activity in appropriately selected patients. The final part examines the considerable phenotypic diversity of isolated medial and lateral compartment osteoarthritis. By characterizing anatomical variation before and after UKA, this work challenges standardized alignment strategies and provides a foundation for more personalized, phenotype-based approaches to knee arthroplasty.
Overall, this thesis demonstrates that successful UKA depends on recognizing individual patient characteristics rather than applying uniform treatment principles. It contributes to a more personalized framework for patient selection, surgical planning, and alignment strategies, ultimately aiming to improve outcomes and broaden the appropriate use of UKA.