The Study of Pinching Type and Power

Ok, In Young; Moon, Myung Sang; Kim, Han Joo; Im, Sun

Abstract

The pinching motion is thought to be one of fundamental hand functions, the power of which has been quantified by measuring it isometrically with variously devised pinch-meters. The present authors describe the investigations on the pinching power of 350 healthy persons, 200 male and 150 female Koreans, by the use of Preston Pinch Gauge. Six kinds of pinch were chosen: (1) thumb index finger tip pinch (1-2TP), (2) thumb-middle finger tip pinch (1-3TP), (3) thumb-index finger pulp pinch (1-2PP), (4) thumb-middle finger pulp pinch (1-3PP), (5) thumb-index-middle finger pulp pinch (3PP), (6) key pinch (KP), which were classified again into 19 kinds according to the shape of thumb, index, middle, or other fingers during each pinch. We describe those as principal type, hyperextension-flexion type, hyperextension type and other type into four. It should be justified to calculate the mean normal value of principal type pinching power in Korean. Principal type of pinch involves 1-2TP, 1-3TP, 1-2PP, 1-3PP, 3PP and KP, as to Hyperextension type of 1-2PP, 1-3PP, 3PP and KP. Other type of pinch involving 1-2TP, 1-3TP, 1-2PP, 1-3PP, 3PP and KP is different from Principal type simply because of the shape of nonjoining fingers during pinch. Generally, the pinching power of Principal type was clearly highest among the four types except for pulp pinches.