Modulation of gluteus medius activity reflects the potential of the muscle to meet the mechanical demands during perturbed walking

Abstract

Mediolateral stability during walking can be controlled by adjustment of foot placement. Reactive activity of gluteus medius (GM) is modulated during the gait cycle. However, the mechanisms behind the modulation are yet unclear. We measured reactive GM activity and kinematics in response to a mediolateral platform translation during different phases of the gait cycle. Forward simulations of perturbed walking were used to evaluate the isolated effect of the perturbation and the GM response on gait stability. We showed that the potential of GM to adjust lateral foot placement and prevent collisions during swing varies during the gait cycle and explains the observed modulation. The observed increase in stance, swing or combined GM activity causes an outward foot placement and therefore compensates for the loss of stability caused by a perturbation early in the gait cycle. GM activity of the swing leg in response to a platform translation late in the gait cycle counteracts foot placement, but prevents collision of the swing foot with the stance leg. This study provides insights in the neuromechanics of reactive control of gait stability and proposes a novel method to distinguish between the effect of perturbation force and reactive muscle activity on gait stability.

Increased use of stepping strategy in response to medio-lateral perturbations in the elderly relates to altered reactive tibialis anterior activity

“…For muscles with a different response in young and older adults, we evaluated the effect of reactive muscle activity on COP movement using our recently developed forward simulation workflow [26]. This allows evaluating the effect of an individual muscle response on the kinematics, which is impossible in the experimental approach where reactive activity of multiple muscles determine the COP movement.…”

“…passive response) and reactive muscle activity (i.e. active response) on the movement of the COP (see [26] for details).…”

Fast responses to stepping‐target displacements when walking

“…We know that it is possible to elicit foot placement adjustments. Such adjustments are not only found after mechanical perturbations (Hof & Duysens, 2013;Rankin et al 2014;Afschrift et al 2018), but also in response to unexpected obstacles (Moraes et al 2004;Weerdesteyn et al 2004;Potocanac et al 2014b) or to stepping stones being displaced (Bank et al 2011;Peper et al 2012;Young & Hollands, 2012;Hoogkamer et al 2015;Mazaheri et al 2015).…”

“…Finally, the question arises as to which muscles contribute to the adjustments, and in particular to what extent the response is bilateral, involving both the swing and stance leg. Based on earlier studies, one might expect that the activity of gluteus medius (GlM) is adjusted both on the swing side (Hof & Duysens, 2013;Rankin et al 2014) and on the stance side (Hof & Duysens, 2013;Afschrift et al 2018). Since these bilateral responses occur about synchronously, they seem to be part of a coordinated postural reaction rather than being an element of anticipatory postural adjustment.…”

Effects of bicycle geometry and riding position on the potential of residual limb muscles to pedaling with a transfemoral prosthesis: a computer simulation study

“…Hip abductors are one of the target muscles for strengthening in prosthetic rehabilitation 1,17,18 because of their ability to support and balance the body during locomotion. [19][20][21] Hip adductors are less focused on but are known to be activated during pedaling with an intact limb. 22 The residual hip adductors tend to retain their volume according to the residual limb length, 23 which is associated with walking performance [24][25][26] .…”