Defining Anatomical Relationships of the Tibial Tubercle to Inform Execution of Tibial Tubercle Osteotomy in Revision Total Knees

Abstract

Data regarding the tibial tubercle anatomy, as it relates to the execution and fixation of a tibial tubercle osteotomy (TTO) in the revision total joint arthroplasty setting, is limited in current scientific literature. This paper aims to define pertinent anatomical relationships in the proximal tibia to inform fixation device design and provide data that may be considered when performing and securing a tibial tubercle osteotomy. We defined eight radiographic dimensions based on seven anatomical landmarks and two lines. These dimensions were measured on 200 retrospectively selected anterior-to-posterior (AP) and lateral knee radiographs with a total knee arthroplasty tibial component present. Measurements were tabulated descriptively and analyzed according to age, sex, and race. The narrowest range of measurements was for tibial tuberosity height at 2.7–13.8 mm and the widest range was for tibial tuberosity length at 47.0–122.7 mm. Sex was the only demographic variable to show statistical significance (p < 0.05) between measurements. Only one measurement, tibial tuberosity origin distance, showed no statistically significant difference between sexes. There were no statistically significant differences in mean values across age groups or races. This paper presents data on anatomical dimensions of the tibial tubercle. The data analyzed in the study underscores the substantial variability of anatomy that may be encountered when performing and securing a tibial tubercle osteotomy during revision total knee arthroplasty. The data also demonstrates that the current recommendation for length of TTO is potentially insufficient to include the necessary portion of the tubercle.