Evaluation of the accuracy of two-dimensional digital templating in primary total knee arthroplasty
Abstract
During knee arthroplasty, surgical planning plays a crucial role in determining the procedure’s
outcome. Two-dimensional, X-ray-based planning software, widely used in everyday orthopedic practice,
offers several advantages, including accessibility, low cost, and avoidance of additional radiation
exposure. However, their accuracy is limited, particularly in total knee replacement surgeries, where
complex anatomical conditions and limb axis deviations present challenges. Our study aimed to identify
demographic and morphological factors that may influence the accuracy of implant size prediction by
two-dimensional planning software. For our research, we used radiographs and patient data from knee
replacement surgeries performed in 2024 at the Department of Orthopedics, Semmelweis University. The
factors examined included age, sex, height, weight, body mass index (BMI), and lower limb axis deviations.
Based on our results, the software accurately predicted the size of both implanted prostheses in 35% of
cases; however, in 16,5% of cases, there was a discrepancy of at least two sizes between the planned and
the implanted components. Although several factors (such as height and age) showed correlation with
planning accuracy, statistical significance was found only in the case of male sex, which proved to be a
predisposing factor for inaccuracy (p = 0.01). In conclusion, although two-dimensional planning software
may not provide perfect accuracy in all cases, its advantages make it a reliable tool for preoperative
planning in routine clinical practice.
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