De-stabilizing and training effects of foot orthoses in multiple sclerosis

Abstract

This study evaluates the effects of dynamic foot orthoses (DFO) on walking and balance performance in people with multiple sclerosis (MS). Sixteen ambulant subjects with MS and ten age-matched healthy control subjects were studied on initial receipt of foot orthoses and after four weeks of daily wear. Walking speed, MS Walking Scale-12 (MSWS-12) and standing balance were assessed with and without orthoses at both these times. During standing, stance width and vision were varied, and performance was quantified using the velocity of the centre of pressure (COP), body sway velocity and the mean COP position relative to the shoe. People with MS walked slower (P <0.001) and showed increased sway when standing (P <0.001). At the first assessment, the foot orthoses caused an increase in sway and a medial and posterior shift of the COP position. At repeat measurement, the DFOs continued to increase sway compared to a shoe only condition. However, MS subjects reported an improvement in the MSWS-12 (P <0.05) and, compared to the initial session, showed decreased sway when eyes were closed both with and without DFOs. Dynamic foot orthoses may increase sway and change COP position by altering foot alignment and/or plantar afferent stimulation. Improvement in body sway over time may be an overall training effect of the DFOs, as MS subjects adapt to the initial de-stabilization.

Postural Control in Multiple Sclerosis: Implications for Fall Prevention

“…Their postural sway increases even more than in controls when they close their eyes [4,12,13], and postural sway in quiet stance is greater in those with MS who are more impaired (higher vs lower Expanded Disability Status Scale [EDSS] score) and in those with progressive rather than relapsing forms of MS [12]. People with MS also are less able to maintain standing with a reduced base of support, such as on one leg or in tandem stance, compared with healthy controls [17].…”

“…When trying to stand still, people with MS sway more than healthy controls [2,4,6,[12][13][14][15][16]. Their postural sway increases even more than in controls when they close their eyes [4,12,13], and postural sway in quiet stance is greater in those with MS who are more impaired (higher vs lower Expanded Disability Status Scale [EDSS] score) and in those with progressive rather than relapsing forms of MS [12].…”

Association of Postural Sway with Disability Status and Cerebellar Dysfunction in People with Multiple Sclerosis

“…We chose to use C7 path length because it provides a measure of body motion indicative of postural sway as observed in clinical examinations, such as the EDSS. This method of measuring standing postural sway has been used in other clinical populations and in previous studies of people with MS. [25][26][27] Sway ratio (EC/ EO) was calculated by dividing EC sway path length by EO sway path length as a measure of visual dependence for balance control, with higher ratios indicating a greater reliance on vision for controlling postural sway.…”

Feedforward postural control in individuals with multiple sclerosis during load release

“…Several studies have demonstrated changes in balance control of individuals with MS, with the main findings being threefold: (1) increased postural sway in quiet stance [22,23] which is exacerbated with a lack of visual inputs [24,25] and under conditions of reduced base of support such as one leg or in tandem stance [26], (2) diminished ability in voluntarily reaching and leaning towards the limits of stability [26,27], and (3) delayed corrective responses and reduced ability to control anteriorposterior sway while recovering from unexpected postural perturbations [14,28,29].…”