Radiolucent Lines and Revision Rates in Attune vs Triathlon TKA: 5-Year Analysis

Overview

This five-year retrospective study compared the incidence of radiolucent lines (RLLs), aseptic loosening, and survivorship between the Attune® and Triathlon® total knee arthroplasty (TKA) systems. Despite concerns about early tibial tray loosening with the Attune® implant, no significant differences in revision rates or patient-reported outcomes were found between the two systems at mid-term follow-up.

Background

Total knee arthroplasty is effective for pain relief and functional restoration in end-stage joint disease, yet up to 10–20% of patients remain dissatisfied postoperatively. The Attune® system was introduced to improve implant conformity and patient satisfaction but has raised concerns regarding early aseptic loosening and increased radiolucent lines at the tibial implant–cement interface. Prior studies have lacked large, single-center data with long-term follow-up, prompting this investigation comparing Attune® with the established Triathlon® system over five years.

Data Highlights

Key Findings

• The Attune® system demonstrated a higher incidence of radiolucent lines at the tibial implant–cement interface compared to the Triathlon® system.
• No statistically significant difference in aseptic loosening or revision rates was observed between Attune® and Triathlon® implants at five years.
• Both implant groups showed clinically meaningful improvements in patient-reported outcomes, including the Oxford Knee Score and EQ-5D-5L quality of life measures.
• The study utilized blinded radiographic assessment with the Modern Knee Society Radiographic Evaluation System to minimize bias in detecting RLLs.
• The redesigned Attune® S + tibial tray, introduced in 2017, aimed to address early loosening concerns by improving cement fixation features.

Clinical Implications

Clinicians can be reassured that despite a higher frequency of radiolucent lines with the Attune® system, this does not translate into increased aseptic loosening or revision at mid-term follow-up. Both Attune® and Triathlon® implants provide comparable functional outcomes and quality of life improvements. Continued surveillance and longer-term data remain important to monitor implant survivorship and guide implant selection.

Conclusion

This largest single-center series with five-year follow-up indicates that while radiolucent lines are more common with the Attune® system, they do not predict higher revision rates or poorer patient outcomes compared to the Triathlon® system. Both implants remain reliable options for total knee arthroplasty at mid-term.

References

1. Meneghini et al. 2020 -- Modern Knee Society Radiographic Evaluation System
2. Irish National Orthopaedic Registry (INOR) 2014 -- Registry Data
3. STROBE Guidelines 2020 -- Reporting Observational Studies