The investigation begins by utilizing biomodeling to elucidate the behavior of structural elements within the human body, with potential applications for technological and scientific advancements. The development of numerical simulations of biological human components is then applied to interpret the mechanical behavior in various service actions that may occur in everyday life (Lohfeld et al. in Ann Biomed Eng 33(10):1295–1311, 2005). This work is a detailed examination of the biomechanical behavior of the knee’s structural complex during bending. The structural and mechanical assessment is achieved by using a numerical simulation of the knee articulation’s movement as a basis for a three-dimensional model of the middle joint of the lower limb. The methodology developed utilizes computed tomography technology and a segmentation process applied to images from a DICOM file (Marquet-Rivera et al. in BioMed Res Int 2021(1), 2021; Serrato-Pedrosa et al. in Prothesis 6(3):429–456, 2024a), resulting in a three-dimensional, complex numerical model (Martínez-Mondragon et al. in Materials 15(21):7843, 2022) that is divided into a finite number of elements (Serrato-Pedrosa et al. in Appl Sci 14(4):1650, 2024b) for using the finite element method. This analysis aims to understand the mechanics of the knee joint’s bending. As a result, we can visually observe the behavior of the different soft components of the joint structure. The results of this analysis were not only positive but also favorable, demonstrating correct articular movement and a healthy structure. This analysis provides a numerical demonstration of human knee flexion. It identifies areas where knee injuries are likely to occur, offering a promising outlook for the potential applications of this research.