The effect of fixation type on the survivorship of contemporary total knee arthroplasty in patients younger than 65 years of age: a register-based study of 115,177 knees in the Nordic Arthroplasty Register Association (NARA) 2000–2016

Mika J Niemeläinen,Keijo T Mäkelä,Otto Robertsson,Annette W-Dahl,Ove Furnes,Anne M Fenstad,Alma B Pedersen,Henrik M Schrøder,Aleksi Reito,Antti Eskelinen

doi:10.1080/17453674.2019.1710373

Abstract

Background and purpose — Cemented fixation is regarded as the gold standard in total knee arthroplasty (TKA). Among working-age patients, there has been controversy regarding the optimal fixation method in TKA. To address this issue, we conducted a register-based study to assess the survivorship of cemented, uncemented, hybrid, and inverse hybrid TKAs in patients aged < 65 years.Patients and methods — We used the Nordic Arthroplasty Register Association data of 115,177 unconstrained TKAs performed for patients aged < 65 years with primary knee osteoarthritis over 2000–2016. Kaplan–Meier (KM) survival analysis with 95% confidence intervals (CI) and Cox multiple-regression model with adjustment for age, sex, and nation were used to compare fixation methods in relation to revision for any reason.Results — The 10-year KM survivorship of cemented TKAs was 93.6% (95% CI 93.4–93.8), uncemented 91.2% (CI 90.1–92.2), hybrid 93.0% (Cl 92.2–93.8), and inverse hybrid 96.0% (CI 94.1–98.1). In the Cox model, hybrid TKA showed decreased risk of revision after 6 years’ follow-up compared with the reference group (cemented) (hazard ratio [HR] 0.5 [CI 0.4–0.8]), while uncemented TKAs showed increased risk of revision both < 1 year (HR 1.4 [1.1–1.7]) and > 6 years’ (HR 1.3 [1.0–1.7]) follow-up compared to the reference.Interpretation — Both cemented and hybrid TKAs had 10-year survival rates exceeding 92–>93% in patients aged < 65 years. Cemented TKA, however, was used in the vast majority (89%) of the operations in the current study. As it performs reliably in the hands of many, it still deserves the status of gold standard for TKA in working-age patients.

Highlights

Patients and methods — We used the Nordic Arthroplasty Register Association data of 115,177 unconstrained total knee arthroplasty (TKA) performed for patients aged < 65 years with primary knee osteoarthritis over 2000–2016
TKA models varied between countries without a common trend and the most commonly used TKA models in the participating countries are given in Table 2
The number of TKAs performed annually grew substantially over 2000–2009, and remained rather stable after that; cemented fixation was used in the vast majority of TKAs over the whole study period (Figure 2)

Summary

Introduction

Patients and methods — We used the Nordic Arthroplasty Register Association data of 115,177 unconstrained TKAs performed for patients aged < 65 years with primary knee osteoarthritis over 2000–2016. As it performs reliably in the hands of many, it still deserves the status of gold standard for TKA in working-age patients Previous studies reported both highest increase in incidence of TKAs and highest risk for revision in patients younger than 65 years of age (Julin et al 2010, Carr et al 2012, Leskinen et al 2012, Meehan et al 2014, Nemes et al 2015, Niemelainen et al 2017). This has increased the interest in finding a more durable fixation method for TKA. The optimal fixation method in TKA still remains controversial for these younger patients

Methods

Results

Conclusion