Effects of Simulated Genu Valgum and Genu Varum on Ground Reaction Forces and Subtalar Joint Function During Gait

Abstract

The mechanical effects of genu valgum and varum deformities on the subtalar joint were investigated. First, a theoretical model of the forces within the foot and lower extremity during relaxed bipedal stance was developed predicting the rotational effect on the subtalar joint due to genu valgum and varum deformities. Second, a kinetic gait study was performed involving 15 subjects who walked with simulated genu valgum and genu varum over a force plate and a plantar pressure mat to determine the changes in the ground reaction force vector within the frontal plane and the changes in the center-of-pressure location on the plantar foot. These results predicted that a genu varum deformity would tend to cause a subtalar pronation moment to increase or a supination moment to decrease during the contact and propulsion phases of walking. With genu valgum, it was determined that during the contact phase a subtalar pronation moment would increase, whereas in the early propulsive phase, a subtalar supination moment would increase or a pronation moment would decrease. However, the current inability to track the spatial position of the subtalar joint axis makes it difficult to determine the absolute direction and magnitudes of the subtalar joint moments.

The trajectory of the centre of pressure during barefoot running as a potential measure for foot function

“…It has been subject of studies investigating medial-lateral stability of the foot [4], effectiveness of foot wear or foot orthoses [5,6], differences between healthy and injured feet [7,8] or the association of plantar pressure data with (rear)foot motion [4,5,9,10]. However, reliability of COP data was barely reported [10].…”

Analysis of Lower Extremity Joint Moment and Power during Squat in Female Patients with Genu Varum

“…It changes the positions of the ground reaction forces and pressure center (Van Gheluwe, Kirby, & Hagman, 2005). Such changes resulted in the difference in the output of the joint moment in the control group.…”

The Effect of Stretching and Elastic Band Exercises Knee Space Distance and Plantar Pressure Distribution during Walking in Young Individuals with Genu Varum

“…The adductor muscles play a role of producing torque in every movement of the hip joints and generating internal rotation torque (Han, 2009) (Gheluwe et al, 2005).…”

“…Genu varum deformity, involves a varus angulation of the tibia in which the knees are separated more than the feet during standing (Gheluwe et al, 2005). It is basically caused by instability of the joints or ligaments, abnormality of the bones, degenerative joint deformity, and pain.…”

“…If genu varum deformities alter the nature of the ground reaction force (GRF), then this would significantly affect the mechanical function of the foot (Gheluwe et al, 2005).…”