Abstract
BACKGROUND
Some papers recently reported conflicting results on implant survivorship in all-poly tibial UKRs. Furthermore, the influence of BMI on this specific implant survivorship remains unclear, since existing reports are often based on small series of non-consecutive patients with different follow up durations, enabling to generate meaningful conclusions.
PURPOSE
To determine the 10-years survival rate of an all-poly tibial UKR in a large series of consecutive patients and to investigate whether a correlation exists between a higher BMI and an increased risk of revision for any reason.
METHODS
A retrospective evaluation of 273 patients at 6 to 13 years of follow-up was performed. Clinical evaluation was based on KSS and WOMAC scores. Subjective evaluation was based on a VAS for pain self-assessment. Radiographic evaluation was performed by 3 independent observers. A Kaplan-Meier survival analysis was performed assuming revision for any reason as primary endpoint. Reason of revision was determined basing on clinical and radiographic data.
RESULTS
The 10-years implant survivorship was 90.8%. Twenty-five revisions (9.2%) were performed and aseptic loosening of the tibial component was the most common failure mode (11 cases, 4%). No significant correlation was identified between failure and patients'BMI. Mean post-operative results for KSS and WOMAC score were 87.0 (st.dev. 14.6) and 87.37 (st.dev. 11.48), respectively. VAS showed a significant improvement (p<0.0001) respect to pre-operative condition.
CONCLUSIONS
Unlike some recent reports, this study demonstrated a satisfactory 10-years implant survivorship using an all-poly tibial UKR. A higher BMI does not reduce survival rate at 6 to 13 years of follow-up.