Morphometric Reappraisal of Gerdy’s Tubercle and Proximal Tibia for Total Knee Arthroplasty

Abstract Purpose The shape and size of Gerdy’s tubercle (GT) vary among individuals. This study aimed to investigate not only the anatomical differences in GT—particularly its size and shape—on dry tibiae and cadavers, but also its precise localization and distances to the tibial plateau. The findings may assist surgeons in preoperative planning for total knee arthroplasty (TKA). In addition, the morphometric structure of the tibial plateau was examined to provide a detailed description of the tibial plateau. Methods A total of 100 dry tibiae and 18 formalin-fixed cadaveric knee-leg specimens were examined using a digital caliper. The width, height, and distances between the GT and surrounding structures were recorded. Morphometric parameters of the tibial plateau were also measured. Statistical analyses were performed using SPSS software. Results GT dimensions and their distances to adjacent structures were proportional to tibial length. The most common GT morphology was triangular, with a smooth surface and the tip at the center. GT height, width, and distances to surrounding structures were greater in cadaveric specimens compared to dry bones. All GT measurements were positively correlated, and tibial plateau parameters demonstrated positive correlations with GT dimensions. Conclusion This study demonstrates that dimensional variations can influence tibial plateau morphometry and that asymmetry exists between the medial and lateral condyles. These findings emphasize the importance of patient-specific implants in total knee arthroplasty (TKA). Moreover, the detailed morphometric description of Gerdy’s tubercle (GT) presented here may serve as a valuable reference for clinical evaluation, surgical planning, and intraoperative decision-making in TKA.