The influence of isometric rotation of the lower limb on the functioning of the knee joint stabilizers and rotator muscles

Purpose: This paper presents an assessment of the influence of isometric rotation of the lower limb in a standing position on the functioning of the muscles stabilizing the knee joint in the frontal plane with the use of modeling the loads on the musculoskeletal system. Methods: The research was carried out in the AnyBody Modeling System software, performing multi-variant simulations of the musculoskeletal system during isometric rotation of the lower limbs. The simulations were carried out using as input data the values of rotating moments and the ground reaction forces acting on foot segments, which were measured using the proprietary Rotenso device and the position of the body segments. Results: The result is the muscular activity of the lower limbs of the selected muscle groups during isometric rotation. Muscle activity was recorded for Sartorius, Tensor fasciae latae, Iliopsoas, Gluteus minimus, Gluteus medius, Gluteus maximus, Piriformis, Quadratus femoris, Obturator internus, Obturator externus, Gemellus inferior, Gemellus superior. Conclusions: Performing isometric rotation allowed for the activation of most of the knee joint stabilizing muscles and rotators of the lower limb. The results indicate that lower limb rotation exercises can be used in physiotherapy in patients with valgus knee.