Several weeks ago my Sensei asked all the black belts to generate a lesson plan taking a bunkai (hidden teaching) from one of the Kata and turn it into a lesson.
This is a move from Pinan San-dan kata that I constantly hear people say is not any sort of useful technique. I got the idea I am showing here from Nakiyama’s book on defense against multiple assailants – but he also shows another use of this technique to defend against a knife in his “Defense against Armed Assailants” book. The entire series is excellent.
Basically when your arm is grabbed from the side, or from behind, one response is to anchor your hand to your hip. Mechanically coupling your arm to your hip then lets you bring the power of shifting your hips to bear on the arm, generating techniques for breaking the attackers grip, off balancing the attacker, or even throwing them. If possible technique should be timed when it will maximally off balance the person grabbing you – like between their steps. This technique is especially useful for with uneven or slippery ground, or stairs. If possible step into the hip twist for extra power. You want their grip fighting the momentum of your entire body.
In the even that the attacker holds on during the twist – they may open themselves as a taget for a back fist to the face or shove outwards. Ideally the strike / shove will continue to unbalance them, while it opens distance for escape or counter attack.