Purpose: Unicompartmental knee arthroplasty (UKA) provides significant benefits to patients with anteromedial osteoarthritis, with good long-term results. Morbidity and mortality rates are lower, and recovery is quicker. These benefits would be advantageous to the octogenarian population whom carry significant comorbidities. The primary aim was to compare the short-term functional outcome at 2 years of UKA in the octogenarian population against a stratified younger cohort of patients. We hypothesised that the octogenarian population would have equally significant improved patient-reported outcome measures.
Methods: Prospective patient-reported outcome measures, including Oxford Knee Score (OKS), satisfaction rates and Euro-Quol (EQ-5D) scores at 1-year and 2-year post-operative data, were collected and analysed. Three hundred and ninety-five medial Oxford Phase 3 UKA implants were evaluated. Mean follow-up was 4.7 years (range 2.1-7.7). Secondary outcomes including revision rates, length of stay, complications and mortality were recorded. Our patient population was stratified into three cohort groups based on age: 60-69, 70-79 and 80-89 years.
Results: The OKS and EQ-5D score improved significantly in all three groups at all post-operative time periods and maintained at 2 years. The OKS at 2 years post-operatively by age was 39.5 (SD 18.6), 39.2 (SD 17.7) and 39.3 (SD 15.9), respectively. No significant difference of implant survival was found between the groups. The overall revision rate was 28/395 (7%). The 90-day mortality in the present series was one patient.
Conclusion: The 2-year short-term functional outcome, revision rates and satisfaction of UKA in the octogenarian population did not differ statistically from other age groups.
Level of evidence: III.
Keywords: Octogenarian; Patient-reported outcome measure; Unicompartmental knee arthroplasty.