Limited experience may influence accuracy of digital templating in total knee arthroplasty: A retrospective analysis

Digital preoperative planning(PP) is a useful and effective tool allowing the surgeon to reduce operative time, minimize blood loss and predict sizes in total knee arthroplasty(TKA). This study aims to analyze the reliability of a specific PP software and to evaluate if experience and TKAs’ type may influence predictions. 128 cases of TKA met our criteria. Age, sex, implant type, femur(F) and tibia(T) sizes were recorded. PP was performed by three observers with different degrees of experience using MediCAD® software Version 6. Observers were blinded to sizes while knowing type of implant used. Predictions were collected and compared with sizes of TKAs actually implanted, dividing them by observer and implant type. Deviation of 1 from actual size considered reliable. Of the 128 TKAs, 30 were Attune, 32 were Persona and 66 were Triathlon. T measurements showed a statistically significant difference(p ​< ​0.05). Intraclass correlation coefficient(ICC) was 0.99 for F and T. Dividing cases by implant type, no statistically significant differences were found within Attune(p ​= ​0.48), Persona(p ​= ​0.91) and Triathlon measurements(p ​= ​0.06). ICCs were lower in Triathlon and Attune than Persona. PP was reliable in 90.4% of cases for F and 88% of cases for T, but it ranged from an accuracy of 75% for F and 71.9% for T in the youngest observer to 100% for F and 98.4% for T in senior observer. PP appears extremely reliable when performed by surgeons with proven experience in TKAs. It is crucial to know the surgical technique of different TKAs in order to avoid PP errors related to component mismatch.