What Knife-Hand Strike Can Tell Us About Hand/Wrist Alignment?

One of the things that we are concerned with in yoga is creating space: space in the flesh body, space in the mind body, space in the emotional body, space for being... It is also taken as a given that the more space, the better.

I am certainly a space enthusiast. I love to spread my toes, for example, and have found that the more I am able to do funny things with my toes, the more ease I find in my hips. The same attitude is largely applied to our hands, regardless of whether we weight-bear on them--as in down dog, handstands, or arm balances--or not, as in warrior 1 or 2 and related poses. We hear over and over again: spread the fingers!

And that's fine, but up to a point. As with anything, yoga is about striking a balance--neither underdoing, nor overdoing. And I think that the finger spreading tends towards the overdoing, especially on the pinky finger side of the hand. What do I mean by that?

Overspreading the pinky/little finger actually creates compression in the outer wrist and enough repetition (i.e. regular yoga practice) can lead to injury in the TFCC (triangular fibrocartilage complex). Say w-hat? Said simply, the wrist is a complex structure, as delicate and exquisite as it can be lethal depending on how you choose to use it. The wrist joint is actually a collection of many bones and joints. Here is a nice visual of the TFCC:

TFCC from the excellent http://classes.kumc.edu/sah/resources/handkines/ligaments/wvsartgroup.htm, showing the major structures in the wrist that can be affected by overspreading the pinky. This is palmar perspective: as if you are looking at someone's palm. The thumb is to the left of the screen, the pinky to the right.

Here is a visual of what I mean by overspreading:

This is my hand. It's as the image above, but the palm is turned down. If I flipped my palm up to face you, the thumb side will be to the left, the little finger to the right.

To me, I've overspread my pinky finger, when it is not lined up with my 5th metacarpal (the outer fleshy part of my hand, also known as the knife edge). So, when I spread my little finger in the this manner, I am actually taking space away from the outer wrist and causing pinching around the articular disc, meniscus homolog, and ulnar collateral ligament; in a sense, the ulna (the forearm bone on the little finger side of the hand) rubs against the triquetrum carpal bone. Here another image to help you locate the triquetrum, where it is labeled:

Triquetrum, shaded in blue from http://classes.kumc.edu/sah/resources/handkines/bone/triquetrum.html. This is palmar perspective: as if you are looking at someone's palm. The thumb is to the left of the screen, the pinky to the right.

How can you know whether you are overspreading the pinky? To me, it's all about awareness and paying attention. With your hand in the air, spread your pinky as much to the side as you can and pay attention to what you feel in your outer wrist but also in the back of your neck and top of the shoulder blade. Do you feel less space in your outer wrist and a tightening in your upper back/neck (I think that would be your levator scapula muscle, quite the villain if you ask me). Also, if your outer wrist is too bunchy and wrinkled in comparison to the rest of your hand/wrist, you are probably overspreading the pinky.

So, what is an optimal spread of the pinky? This is where the knife-hand strike comes in, or more commonly known as the karate chop. (As a caveat, here is an article on why the karate chop is a useful tool to have in your bag of tricks.) In a karate chop hand, the knife edge of the hand and the pinky are lined up in a straight line (as far as anything in the human body is straight), which creates stability along the back line of the arm. We've all seen bricks being shattered with a knife-hand strike.

The pinky is associated with the Deep Back Arm Line, which includes your triceps and rotator cuff muscles. The rotator cuff muscles do contribute to movement of the arm bone, but they have the important function to stabilize the head of the armbone in the shallow socket of the shoulder blade while the armbone is in motion. You can feel this stability simply by taking your arms out to the side but still in the front plane of the body (with the palms facing forward and the hands slightly above shoulder level; the latter helps with releasing your upper traps), so that the knife edge of your hand and your outer forearm are pointing down toward the floor. Experiment with overspreading the pinky towards the floor (so that your outer wrist bends or kinks if you wish) and lining up the pinky with the knife edge of your palm, so that the outer wrist is stable and smooth. Although overspreading the pinky does create engagement, it feels more like gripping and muscles along the arms either overwork or underwork. It's kind of like creating a kink in a hose, the energy stops flowing smoothly. When the pinky lines up with the knife edge of the hand, there is space, but there is also stability, and you can pulse the energy along the deep back arm line: drawing from the pinky through the triceps and into the rotator cuff muscles, as you extend out from the shoulder blades through the pinkies. Further, when the pinky overspreads to the side, it's more likely that the mound of the index finger will have trouble connecting with the floor, which by definition will put pressure on the outer wrist.

Let me know what you think and share your experience. Thanks for reading!

Here are a couple of photos of what is an optimal spread of the pinky for me. Do you notice the difference with the image above? The little finger and the fleshy outer part of my palm are on a nice continuous line.