Comparing Survivorship of Symmetric Versus Asymmetric Tibial Augments in Aseptic Revision Total Knee Arthroplasty.

BACKGROUND: This study evaluated radiolucency in patients who underwent aseptic revision total knee arthroplasty using either symmetric or asymmetric modular tibial augments and compared 5-year all-cause and nonseptic revision-free survivorship between groups. METHODS: An institutional database was queried from January 2013 to September 2023 to identify patients who underwent aseptic revision total knee arthroplasty where tibial augments were utilized and were then stratified into symmetric and asymmetric tibial augment groups. Postoperative radiographs were reviewed for radiolucent lines through available follow-up. Kaplan-Meier survivorship curves were then created to compare rates of revision between both groups over 5 years. A total of 76 patients who had symmetrical augments and 27 patients who had asymmetrical augments were analyzed at a mean follow-up time of 3.5 years (range, 1.0 to 10.1) and 4.4 years (range, 1.0 to 8.8), respectively. RESULTS: Radiolucency was noted in 44.4% (12 of 27) of patients who had asymmetric augments and 44.7% (34 of 76) of those who had symmetric augments (P = 1.0). The 5-year all-cause revision-free survivorship for the entire cohort was 76.6%. The 5-year all-cause and nonseptic revision-free survival were lower in patients who had asymmetric tibial augments compared to symmetric (56.1 versus 85.5%; P = 0.021 and 64.8 versus 89%; P = 0.019, respectively). Patients who had symmetric tibial augments had 84% less risk of nonseptic revision when compared to patients who had asymmetric tibial augments (P = 0.035). Subanalysis demonstrated that asymmetric tibial augment constructs with metaphyseal cones had similar 5-year nonseptic revision-free survivorship to symmetric tibial augment constructs with (75.0 versus 97.0%; P = 0.13) or without metaphyseal cones (75.0 versus 82.5%; P = 0.54). CONCLUSIONS: Patients who had symmetric tibial augment constructs exhibited similar rates of radiolucency but higher survivorship compared to those with asymmetric constructs overall. However, when metaphyseal cones were utilized, survivorship was equivalent. LEVEL III EVIDENCE: Retrospective Cohort Study.

Duke Scholars

Author Thorsten Markus Seyler Orthopaedic Surgery

Author Sean Ryan Orthopaedic Surgery

Author Michael Paul Bolognesi Orthopaedic Surgery

Author William Arthur Jiranek Orthopaedic Surgery