Summary

 Implant survival of cemented and cementless Oxford mobile-bearing medial UKA is significantly associated with age.

Abstract

Aims
The primary objective of this study was to compare short-term implant survival between cemented and cementless fixation for the mobile-bearing Oxford medial UKA across various age groups. The secondary objectives were to compare modes of failure and evaluate patient-reported outcomes.

Methods

A total of 25,762 patients, comprising 8,023 cemented (31.1%) and 17,747 cementless (68.9%) medial UKA cases, were included from the Dutch Arthroplasty Register. Patient stratification was performed based on age: <50 years, 50-60 years, 60-70 years, and >70 years. Survival rates and hazard ratios were computed. Modes of failure were described and postoperative change in baseline for the OKS and NRS for pain at 6- and 12-months follow-up were compared.

Results

The 2.5-year implant survival rate of cementless UKA was significantly higher compared to cemented UKA in patients younger than 60 years (age <50 years: 95.9% vs. 90.9%; p=.007 and 50-60 years: 95.6% vs. 94.0%; p=.009). Cemented UKA exhibited significantly higher revision rates for tibial loosening (age <50 and 60-70 years), while cementless UKA was associated with higher revision rates for periprosthetic fractures (age >60 years). Patient-reported outcomes were similar between both fixation techniques, irrespective of age.

Conclusion

Cementless fixation resulted in superior short-term implant survival compared to cemented fixation among younger patients undergoing Oxford mobile-bearing medial UKA. Distinct failure patterns between fixation techniques emerged across various age groups, with revisions for tibial loosening being associated with cemented UKA in younger patients, while revisions for periprosthetic fractures were specifically identified among elderly patients undergoing cementless UKA.