In this article, I will explain the structure of the wrist.

At first glance, the wrist looks easy to draw, but if you observe it carefully, you will probably notice that there are joint protrusions depending on the position of the wrist.

The protrusion of the wrist on the pinky side is particularly pronounced.

So, in this article, I will explain this wrist bulge from the skeletal mechanism.


Let’s learn about the skeleton of the wrist

In this article, I will explain the skeletal structure of the wrist.

The wrist has two bones, the radius on the thumb side and the ulna on the small finger side.

The protrusion in the wrist area originates from the sternal process located at the tip of the ulna.

The radial side also has a stalk-like process, but the protrusion is not as large as that of the ulna.

You can draw a bony hand by drawing the stapes of the radius and ulna prominently.


How the ulnar stapes looks

The stapes protrudes and retracts depending on the direction of rotation of the wrist.

So now let’s look at how to rotate the wrist.


Forearm structure – Rotation of the radius

Rotation of the wrist is achieved by rotating the radius from the elbow.

The radius, which is attached to the thumb side, rotates around the ulna.

When the thumb is rotated inward, the radius crosses over the ulna, which is how the ulnar stapes is raised.

Actually hold both hands in front of your face and observe.

When you rotate your thumbs inward, the ulnar stapes will be raised.

On the other hand, when the thumb is turned outward, the cross between the radius and ulna disappears and the stapes retracts.

There is no protrusion of the stapes, but the bony shape of the stapes may be thinly raised.

However, basically when the wrist is rotating outward, the bumps are not as pronounced as when it is rotating inward.

Observe your wrist with this difference in mind.



The above is an explanation of the structure of the wrist.

In summary, the following four points are important.

・The protrusion on the little finger side of the wrist corresponds to the stalk-like process of the ulna.
・The ulnar stalk process moves in and out depending on the rotation of the wrist.
・When the thumb is rotated inward, the stapes comes out.
・Rotating the thumb outward causes the stapes to retract.

In particular, when drawing the wrists of male characters, if you are conscious of the ulna, you can accentuate the sexiness of the character by creating a rugged feeling of bones.

Please take this into consideration.

(Text and pictures by Setsu Yoshida)