Anatomy Basics: Skeletal Anatomy of the Hand, the wrist bones

Bones of the hand
I want to focus on the bones in the hand for a bit. This is because I noticed that many of the students I work with struggle with drawing hands and I thought this would be good subject to cover here in order to help out those of you who have the same difficulties.

Even though hands are a challenge to draw, one way to learn to draw hands is to start looking at and thinking of the hands structurally. Understanding the structures that make up the hand allow us to see what kind of shapes these structures will create in the hand and to draw the hand accurately in different positions.


Today, we are going to look at the skeletal structure of the hand to identify the grouping of bones at the wrists and see how they help with the movement of of the hand.

Let's take a look.


The Carpal Bones

The carpal bones are a group of eight bones at the base of the hand. As a group, these bones are called the carpus. These make up the hand bones of the  of the wrist.

I like to think of this group as a somewhat oval shaped form that allows the hand to pivot against the the bones of the forearm (radius and ulna) allowing for the hand to bend at the wrist.

This joint between the carpal bones and the bones of the forearm allow for the hand to flex, extend, adduct and abduct.



 Flexion at the Wrist

First, the carpal bones allow for flexion at the wrist.


This simply means the carpal bones allow the palm of the hand to bend towards the forearm.


Extension at the Wrist

The carpal bones also allow for extension at the wrist.

This simply means the carpus allows the palm of the hand to bend away from the forearm.

Abduction at the Wrist

The carpal bones allow for abduction of the hand at the wrist.

This simply means the carpus allows the hand to tilt slightly towards the radius (the arm bone closest to the thumb at the wrist).

Adduction at the Wrist


The carpal bones allow for abduction of the hand at the wrist.

This simply means the carpus allows the hand to tilt  slightly towards towards the ulna (the arm bone closest to the pinky finger side of the hand) at the wrist.

The hand has much more range of movement when we flex or extend it. When we adduct or abduct the hand at the wrist the range of motion is much more limited.

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Take some time to examine these actions by moving your hand around to see for yourself the movements above. This will allow you to see the range of motions the hand can make at the wrist and the possible positions the hand can be in relative to the arm. 

When you do this, pay special attention to the shapes of the wrist in those different positions. This will help you better understand how the hand connects to the arm.