Tutorial 101 - The Synovial Joints (Patreon)

Here's a breakdown of the most important joints for the artist studying anatomy.

The Synovial joints are six types of joints that artists need to understand because these are the most movable types of joints in the body.

We’ll know how to draw them on the human form if:

• we know what these joints look like
• how they move
• how they effect the tissue surrounding them
  

Synovial joints, so named for the synovial fluid that fills the joint cavity, are the most mobile joints in the body. Without these joints, our bodies couldn’t move the way they do. 

There are six types of synovial joints in the body:

Hinge joint 

• Shaped like a hinge, allows for a swinging motion (ex: elbow, fingers).

Saddle joint

• Similar to hinge joint, but allows for a greater range of motion (ex: thumbs, which can swing in a hinging motion but also move from side to side).

Glide (plane) joint 

• Allows bones to slide along one another, allowing for movement in many directions, as well as increased flexibility (ex: between metatarsal bones in foot).

Ellipsoid (condyloid) joint 

• Allows movement in two planes, allowing flexion, extension, adduction, abduction, and circumduction (ex: wrists, fingers where philangeal bones meet in fingers).
  

Pivot joint

• Allows for rotational movement (ex: between neck vertebrae)

Ball and socket joint 

• A partially spherical end lies within a socket, allowing for the greatest range of multidirectional motion of all the joints (ex: hip, shoulder)

We'll go much further into these joints in upcoming tutorials, their anatomical actions, where they are found in the skeleton and how they effect the surrounding tissue.