Outcomes of cementless fixation in medial unicompartmental knee arthroplasty: review of recent literature

Introduction: Medial unicompartmental knee arthroplasty (UKA) is considered the most effective treatment for anteromedial knee osteoarthritis. Cementless fixation of UKA was developed to reduce aseptic loosening. We performed a review of the recent literature to assess the latest outcomes of cementless UKA. Methods: A review of English literature was performed on Medline through Pubmed. Retrospective or prospective studies with at least 2 years of follow-up (FU) and at least 20 patients were included. The PRISMA 2009 flowchart and checklist were considered to edit the review. Survival rate, revision rate, time for revision, incidence of radiolucent lines and reasons for revision (such as aseptic loosening, osteoarthritis progression, bearing dislocation or periprosthetic fracture) were extrapolated from the papers. Results: Nineteen articles were included in the review, only 2 with a level of evidence of I. A total of 3432 UKA with a FU range of 24–132 months were analyzed. The studies showed good clinical and functional outcomes. In 12 studies, survival rate were more than 90%. Revision rate for aseptic loosening were lower than 2% for 15 studies. Conclusion: Cementless UKA represents a surgical option allowing low revision rate. Further high-quality long-term studies would better clarify complications, clinical and radiological results of this promising fixation method. © 2020, Istituto Ortopedico Rizzoli.