Toe Flexor Muscle Strength as a Measure of Motor Function in Community-Dwelling Elderly People

Abstract

Purpose: The purpose of this study was to show the validity of toe flexor muscle strength as a measure of motor function in community-dwelling elderly people. Methods: We selected 240 community-dwelling elderly people (age, 75.8±6.3 years [mean±standard deviation]). Toe flexor muscle strength was measured by a toe dynamometer that was developed in our department. The knee extension power, single-stance time, functional reach test (FRT) scores, maximum walking velocity, and timed "up-and-go" test (TUGT) scores were measured to evaluate the motor function. Analysis of variance and t tests were used to assess age and gender differences in toe flexor muscle strength and motor function measures. Correlation analysis and multiple regression analysis were performed to determine the relationships between toe flexor muscle strength and motor function measures. Results: All motor functions were found to deteriorate with age. Toe flexor muscle strength was significantly different between individuals of the>85-year age group and those of younger age groups. Further, toe flexor muscle strength and knee extension power were found to differ significantly in men and women. Toe flexor muscle strength was found to be correlated with balance and mobility performance measures. Multiple regression analysis revealed that toe flexor muscle strength was a significant and independent predictor of the single-stance time, FRT scores, maximum walking velocity, and TUGT scores. Conclusion: Toe flexor muscle strength was found to be a significant and independent predictor of the balance and mobility functions in community-dwelling elderly people, and was also found to decrease significantly with age. Therefore, toe flexor muscle strength is a useful measure of motor function, and it is a parameter to be considered in health promotion programs for elderly individuals.