Postural Control on the Compliant Surface in the Absence of Somatosensation

Translated Titles



陳怡如(Yi-Ru Chen);林桑伊(Sang-I Lin)

Key Words

軟墊 ; 體感覺 ; 姿勢搖晃 ; Rubber foam ; Somatosensation ; Postural sway



Volume or Term/Year and Month of Publication

31卷1期(2006 / 02 / 01)

Page #

8 - 14

Content Language


Chinese Abstract


English Abstract

Background and Purposes: Rubber foams have been used extensively clinically to alter somatosensory inputs from the ankle joints and the foot soles so that the compensatory ability of the visual and vestibular systems can be examined. However, it is not clear if other balance-related factors are also altered in such maneuvers. The purpose of this study was, by experimentally inducing somatosensory loss of the foot and ankle, to verify if the somatosensation of the ankle and foot was the only factor changed during standing on the foam. Methods: Somatosensory loss was induced in 14 healthy subjects by inflating pneumatic cuffs above bilateral ankle joints to produce vascularischemia. Postural sway was assessed under four conditions: pre-ischemia ground standing, pre-ischemia foam standing, post-ischemia ground standing, and post-ischemia foam standing. The motion of a reflective marker placed on the center of the sacrum was used to reflect postural sway, and the variables of interest included trajectory, maximum range of anterior-posterior (AP) and medial-lateral (ML) trajectory, and mean instantaneous velocity in the AP and ML directions of the sacrum marker. Results: Multivariate ANOVA showed a lack of significant interaction between somatosensory status and support surface, and significant main effects of both on postural sway. Foam standing led to greater postural sway than ground standing even after a total loss of somatosensation of the feet. Conclusions: Somatosensory inputs might not be the only factor changed when standing on a compliant surface because greater postural sway occurred even after a total loss of somatosensation. Clinically, a declined balance performance in foam standing should not be completely attributed to impaired visual or vestibular compensation.

Topic Category 醫藥衛生 > 醫藥總論