Grip and Key Pinch Strength of the Aged Subjects in the Community Dwellers and Institutional Residents

Abstract

The relationship between aging and grip and key pinch strength has been investigated. However, there have been few comparative studies focusing upon the strength of aged community dwellers and institutional residents. The purpose of this study was to compare these strength of the right dominant hand between community dwellers and institutional residents using a hand dynamometer and a pinch gauge. Two hundred and five subjects, 54 male and 38 female community dwellers (CD group), and 23 male and 90 female institutional residents (IR group), participated in this study. Their mean age was 79.5 years (range=70-89). For each grip and key pinch strength test, the standardized position recommended by the American Society of Hand Therapists and Mathiowetz et al. was used. The male grip strength decreased with aging at a declining rate with significance (r=0.43 and p<0.0015 in CD group, and r=0.44 and p<0.0349 in IR group). The male key pinch strength apparently decreased with increasing age (r=0.35 and p<0.0113) in CD group, while no siginificance was found (p<0.1034) with a declining rate (r=0.35) in IR group. The female grip strength showed decreasing linear regression with aging (r=0.45 and p<0.0054) in CD group, but a less moderate one (r=0.29 and p<0.0062 in IR group). The female key pinch strength was observed with significant difference (r=0.37 and p<0.0252) in CD group and a more apparently mild one in IR group (r=0.22 and p<0.0446). It is characteristic that the regression lines of the two groups in the females were closer than those in the males. It may be understood that the amount of females’daily hand activities such as handling items in the kitchen and washing might be differentiated in the living places to a lesser extent from the males’. The females in both groups may be expected to retain a greater percentage of manual activity in their daily life than the males. The correlation between aging and muscle strength clearly reflected the characteristics of the grip and key pinch strength of the aged in different environmental status. The present study provides therapists with valuable information about the treatment in clinical setting when making a program which involves grip and pinch activities for the aged.