Effect of lower limb strength on falls and balance of the elderly

Abstract

Objective: To assess the effect of lower limb strength on falls and balance in community-dwelling elderly persons by a health status questionnaire, evaluation of lower limb strength and balance.

Method: A total of 86 subjects (age 69.8±5.3) were categorized into one of two groups, "Fallers" and "Non-fallers". Thirty one participants who had reported the experience of having fallen unexpectedly at least once in the past year were assigned into the group "Fallers", and the remaining 55 subjects having no fall history in the past year, "Non-fallers". A self-assessment questionnaire was taken. Lower limb strength was measured by a "Chair stand test". Balance was measured by the stability index of the fall risk test protocol of Balance System SD® (Biodex, New York, USA). The differences between the two groups were compared and the correlation between lower limb strength and balance were analyzed.

Results: The questionnaire demonstrated no significant differences between two groups. The "Chair stand test" showed a significantly less for the "Fallers" (p<0.05). The stability index was significantly greater in the "Fallers" group (p<0.05). There was a moderate negative correlation between the "Chair stand test" and the "Stability index" (R=-0.576, p<0.01).

Conclusion: This study suggests that the "Chair stand test" is a useful screening process for lower limb strength which correlates to risk for falls and balance in the elderly.

Keywords: Balance; Elderly; Fall; Lower limb strength.

Fig. 1

Chair stand test.

Fig. 2

Fall risk test protocol of Balance System SD® (Biodex, New York, USA). (A) Report of fall risk test protocol. (B) Formula to calculate "Stability index". YRS: Years.

Fig. 3

Correlation between "Chair stand test" and "Stability index"

Fig. 4

ROC curve of "Chair stand test" and "Stability index". (A) Chair stand test. (B) Stability index.