Title : Defining optimal follow-up for computer-navigated total knee arthroplasty: A 10-year analysis of implant survivorship, outcomes, and patient factors in 1,677 cases
Abstract:
Background: Computer navigated total knee arthroplasty (TKA) is an effective and established treatment for knee arthritis. However, the optimal duration for patient follow-up remains unclear. This study aims to determine the ideal follow-up period and analyse long-term outcomes across diverse patient populations.
Methods: This prospective, single-centre study followed 1,677 consecutive computer navigated TKAs for a minimum of 10 years. Patient-reported outcomes, satisfaction rates, implant survival, and radiographic outcomes were assessed at multiple time points. Subgroup analyses were performed based on age, gender, and BMI to identify patient factors influencing outcomes and follow-up needs. Descriptive statistics were presented as means and standard deviations (SD) for continuous variables, and as frequencies and percentages for categorical variables. Statistical significance was set at p<0.05.
Finding: Patient satisfaction rates stayed consistently high, with ~95% in the first 5 years and 90% at 10 years. Oxford Knee Scores (OKS) improved significantly from preoperative levels (17.9) to 1 year postoperatively (37.7), with both OKS and satisfaction rates plateauing from the first year. Implant survivorship was 96.4% at 17 years for all-cause revisions. Younger patients (<55 years) reported lower function, satisfaction and higher revision rates. No significant differences in revision rates were observed across BMI categories, although range of motion at 1 year negatively correlated with BMI. 83.2% of cases achieved the desired hip-knee-ankle angle (177°-183°) at 6 weeks postoperatively.
Interpretation: Computer-navigated TKA demonstrates high patient satisfaction, good functional outcomes, and excellent 10-year implant survivorship, with the majority of clinical benefits achieved within the first postoperative year. This suggests the initial 12 months as the critical follow-up period. While outcomes generally plateau thereafter, tailored strategies may further optimise results for younger and higher BMI patients. These findings significantly inform clinical practice, follow-up protocols, and resource allocation in TKA.
Funding: Study was funded by Aesculap AG, Tuttlingen, Germany
Keywords: Total Knee Replacement, computer-assisted, long-term outcomes, osteoarthritis, implant survivorship, age, BMI, patient reported outcome, satisfaction
