Effect of Heel Height on the Foot in Unilateral Standing.

Abstract

The purpose of this investigation was to study the effect of elevating the heel during unilateral weight-bearing on structure of the foot, especially a "flat" foot, and on function of the foot in maintaining balance. We examined 16 healthy women, 21 to 23 years of age, who stood unilaterally on the right foot with the heel elevated 0, 5, 10, 15, 20, 25, 30, and 40 mm. We measured height of the medial longitudinal arch, rearfoot pronation (calf-to-calcaneus angle), displacement of center of pressure under the foot during ten seconds, and mean position of the center of pressure during those ten seconds. Elevating the heel raised the medial longitudinal arch, reduced rearfoot pronation, increased length of displacement of the center of pressure, and brought the mean center of pressure forward and medially. In feet that initially had strong rearfoot pronation, presence of an initially high medial longitudinal arch was associated with a greater curtailment of rearfoot pronation when the heel was elevated than if the arch was not initially high. These results suggest that elevating the heel of a shoe can help reduce the signs of a flat foot, but the accompanying decrease in balance stability and shift of pressure toward the first metatarsal head makes the use of elevated heels questionable as a therapeutic measure.

The Relation between the Changes of Postural Achievement, Lower Limb Muscle Activities, and Balance Stability in Three Different Deep-squatting Postures

“…However, this finding suggests that the effect occurring under the TT condition indicates an imbalanced posture during tiptoe strategy according to the wider area of occupation. Since static squatting could be equated to standing in terms of nonsupported vertical posture, our results are generally consistent with those of previous studies in which the tiptoe posture contributed to posture instability (Dionisio et al, 2006;Hof et al, 2005;Shimizu and Andrew, 1999).…”

“…Behaviorally, once TT was achieved, the hip and head of the metatarsophalangeal joint angle increased as the heel lifted up and affected the angle between the feet, causing it to be more open. Under this condition, Shimizu and Andrew (1999) suggested that the change of body angle was closely related to segmental body linkage coordination, which occurred as a compensation of balance control; therefore, the center of gravity is maintained within the BOS.…”

“…1C). The GRF distribution as a representation of COP displacement was plotted in the anterior-posterior (A-P) and right-left (R-L) directions and was presented in the sway trajectory which has been used in previous investigations (Chiari et al, 2002;Shimizu and Andrew, 1999;Uetake et al, 2004) and the standard deviations of COP displacement in A-P and R-L direction were averaged for statistical analysis. One-way ANOVA was employed to test the effect of squatting strategy on the %MA of EMG, body joint angles, GRF, and feet projection.…”

“…There may be many reasons for adopting the tiptoe squatting posture, but few studies have investigated the relation between deep squatting and the burden it places on lower limb muscles and balance stability. One assumption is that the tiptoe posture in deep squatting may result in less activity of certain lower extremity muscles during heel supination (Shimizu and Andrew, 1999;Tansey and Briggs, 2001 (Nordin and Frankel, 2001;Tansey and Briggs, 2001), in the present study we applied a 15°slope for the feet in light of the burden of the lower limb muscles during squatting. Since daily activities often involve deep squatting, it is important to understand how posture muscles are controlled in maintaining balance stability.…”

Análise do arco longitudinal medial em adolescentes usuárias de calçados de salto alto

“…São descritos muitos fatores predisponentes do pé plano, como idade, sexo e tipo de calçado utilizado, além de seu uso ou não [17][18][19] . Já Shimizu et al 20 relatam que, dentre os fatores predisponentes para o pé cavo, o uso de calçado de salto alto leva ao aumento na altura do arco longitudinal medial devido à tensão gerada na fás-cia plantar pela hiperextensão dos dedos.…”