A typical walking gait pattern depends on various important biomechanical functions which are referred to as the determinants of gait. The six determinants of gait were initially published by Saunders in 1953, and have been extensively accepted with many modifications as well as minor concerns. These determinants of gait are considered necessary as they facilitate a more efficient gait by the minimizing the up and down center of mass motion that leads to a reduction in the metabolic energy necessary for movement. The theory underpinning this is that a improved control of these determinants of gait contributes to an increase in power conservation and much more efficient movement. This model which does underpin these determinants of gait are in conflict with the ‘inverted pendulum’ theory which considers the static stance leg acts as a pendulum that follows an arc. The biomechanics community will continue to debate the worthiness of the two theories.
The 6 determinants of gait and the way they have an impact on the centre of mass (COM) motion as well as energy preservation are:
1. Pelvic rotation: The pelvis swivels side to side during normal gait to assist in the advancement of the opposite side via decreased hip flexion and extension. This has an effect on the decrease in metabolic energy and also the increased energy efficiency by lessening the vertical COM displacement.
2. Pelvic tilt: Throughout typical gait there's a slanting with the swing period aspect of the pelvis that is handled by the hip joint abductor muscles. This muscle motion decreases the raising of the COM through the changeover from hip joint flexion to extension. This would lower the use of metabolic energy and increase energy conservation by reducing vertical COM movement.
3. Knee joint flexion during stance phase: The knee is extended at heel contact and then begins to flex when the foot is on the floor. The knee flexion will lower the height with the vertical trajectory with the COM leading to some energy conservation.
4. Motion in the foot and ankle: The ankle joint rockers at heel contact and mid-stance brings about a decline in center of mass movement through the shortening of the leg play a role by reducing the center of mass up and down movement.
5. Knee motion: The movement of the knee is related to the ones from the ankle and foot motions and leads to the decrease in the COM vertical displacement which contributes to reductions in the center of mass displacement and energy cost.
6. Lateral displacement with the body: this lateral motion with the pelvis or a relative adduction of the hip is mediated by the effect of the tibiofemoral angle as well as relative adduction of the hip joint to minimize up and down COM movement. It is deemed that this characteristic takes on a significant function in ensuring the efficacy in normal walking.
These 6 determinants of gait happen to be logically appealing since they allow us to focus on some important aspects to hold the COM motion smooth to improve the efficacy of walking. Nevertheless, some current investigations queries if most or a number of the determinants are actually that essential in the general scheme of the events which occur during the walking cycle. Despite that taking into consideration these kinds of determinants is key in comprehending gait impairment.