Association between fixation type and revision risk in total knee arthroplasty patients aged 65 years and older: a cohort study of 265,877 patients from the Nordic Arthroplasty Register Association 2000–2016

Tero Irmola; Ville Ponkilainen; Keijo T Mäkelä; Otto Robertsson; Annette  W-Dahl; Ove Furnes; Anne M Fenstad; Alma B  Pedersen; Henrik M  Schrøder; Antti Eskelinen; Mika J  Niemeläinen

doi:10.1080/17453674.2020.1837422

Authors

Tero Irmola Coxa Hospital for Joint Replacement, and Faculty of Medicine and Health Technologies, University of Tampere, Tampere, Finland
Ville Ponkilainen Coxa Hospital for Joint Replacement, and Faculty of Medicine and Health Technologies, University of Tampere, Tampere, Finland
Keijo T Mäkelä Finnish Arthroplasty Register, National Institute for Health and Welfare, Helsinki, Finland; Department of Orthopaedics and Traumatology, Turku University Hospital, Turku, and University of Turku, Turku, Finland
Otto Robertsson The Swedish Knee Arthroplasty Register, Department of Orthopedics, Skane University Hospital, Lund, Sweden. Department of Clinical Sciences, Orthopedics, Lund University, Sweden
Annette W-Dahl The Swedish Knee Arthroplasty Register, Department of Orthopedics, Skane University Hospital, Lund, Sweden. Department of Clinical Sciences, Orthopedics, Lund University, Sweden
Ove Furnes The Norwegian Arthroplasty Register, Department of Orthopaedic Surgery, Haukeland University Hospital, Bergen, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway
Anne M Fenstad The Norwegian Arthroplasty Register, Department of Orthopaedic Surgery, Haukeland University Hospital, Bergen, Norway
Alma B Pedersen Department of Clinical Epidemiology, Aarhus University Hospital. Denmark and Danish Knee Arthroplasty Registry
Henrik M Schrøder Department of Orthopaedic Surgery, Naestved Hospital, Denmark
Antti Eskelinen Coxa Hospital for Joint Replacement, and Faculty of Medicine and Health Technologies, University of Tampere, Tampere, Finland
Mika J Niemeläinen Coxa Hospital for Joint Replacement, and Faculty of Medicine and Health Technologies, University of Tampere, Tampere, Finland

DOI:

https://doi.org/10.1080/17453674.2020.1837422

Abstract

Background and purpose — The population of the Nordic countries is aging and the number of elderly patients undergoing total knee arthroplasty (TKA) is also expected to increase. Reliable fixation methods are essential to avoid revisions. We compared the survival of different TKA fixation concepts with cemented fixation as the gold standard.

Patients and methods — We used data from the Nordic Arthroplasty Register Association (NARA) database of 265,877 unconstrained TKAs performed for patients aged ≥ 65 years with primary knee osteoarthritis between 2000 and 2016. Kaplan–Meier (KM) survival analysis with 95% confidence intervals (CI) and the Cox multiple-regression model were used to compare the revision risk of the fixation methods.

Results — Cemented fixation was used in 243,166 cases, uncemented in 8,000, hybrid (uncemented femur with cemented tibia) in 14,248, and inverse hybrid (cemented femur with uncemented tibia) fixation in 463 cases. The 10-year KM survivorship (95% CI) of cemented TKAs was 96% (96−97), uncemented 94% (94−95), hybrid 96% (96−96), and inverse hybrid 96% (94−99), respectively. Uncemented TKA was associated with increased risk of revision compared with the cemented TKA; the adjusted hazard ratio was 1.3 (95% CI 1.1−1.4).

Interpretation — Cemented, hybrid, and inverse hybrid TKAs showed 10-year survival rates exceeding 95%. Uncemented fixation was associated with an increased risk of revision in comparison with cemented fixation. As both hybrid and inverse hybrid fixation were used in only a limited number of TKAs, indicating possibility of selection bias in their favor, cemented TKA still remains the gold standard, as it works reliably in the hands of many.