Evaluation of lower limb function of age change by using principal component estimation

Abstract

Falling is one of the most common and serious problems because advancing age has been associated with muscle weakness, reduced cutaneous sensation and deterioration of walking ability. We have investigated relation between the fall and lower limb function by development of evolution methods for lower limb function using principal component analysis so far. This paper focuses on change of the value of the evaluation of lower limb function, such as value of walking ability, value of muscle strength of lower limb and value of flexibility of ankle. The subjects were 16 healthy young volunteers (mean ± S.D: 19.9 ± 0.6 years) and 10 healthy aged volunteers (mean ± S.D: 80.6 ± 6.1 years)) living in a special elderly nursing home. All subjects completed the informed consent procedures, and agreed to participate in this study. Measurement items related to lower limb function were selected from the items which we have ever used. Selected measurement items of function of lower are distance of extroversion of the toe, angle of flexion of the toe, maximum width of step, knee elevation, moving distance of greater trochanter, walking balance, toe-gap force and rotation range of ankle joint. The young group demonstrated the factor of 1.6 greater the assessment score of walking ability compared with the aged group. The young group demonstrated the factor of 1.4 greater the assessment score of muscle strength of lower limb compared with the aged group. The young group demonstrated the factor of 1.2 greater the assessment score of flexibility of ankle compared with the aged group. Parameters with significant differences between the elderly group and young group were selected and summarized by principal component analysis into lower ability assessment indices including walking ability and flexibility of ankle. The results suggested that it was possible to assess the lower limb function of aged and young numerically and to advise on their foot function.