The Spearpoint Knuckle

The middle-finger knuckle fist (nakadaka-ken) of karate-& resembles this way of shaping the hand. As is shown in Figure, the projecting middle finger must be tightly squeezed between the supporting ring finger on one side and the forefinger on the other; further, the inner tip of the thumb must press hard up and under the terminal row bone phalange of the middle finger. Held in this fashion, the middle finger will not, even under hard impact, slip back in line with the other fingers. The formation is used for both thrust and strike actions against vulnerable points, such as the temple, the back of the hand, the eyes, and other facial areas.