Whilst scrolling through Instagram this morning I came across this video of a man moving his scapulas (shoulder blades), His comment under the video is true it does feel 'awesome' to really move our scapulas. Most of us only move them a fraction of their full movement range each day and overtime, with limited movement, the fascia and muscles fibres surrounding the scapula can become stiff and stuck.
What is the Scapula?
The scapula is a relatively flat bone which joins to the humerus, the bone in our upper arm and it connects to the clavicle, the shoulder blade. These three bones create the shoulder. We have two scapulae, one for each shoulder. These images taken from Essential Anatomy 5 show how the scapula and humerus rest together at the ball and socket shoulder joint, the glenohumeral joint. The clavicle rests just above this joint. The medial edge of the scapula, which is the edge closest to the spine, moves freely. This movement creates the shoulders movement.
Which muscles move the scapula?
Amazingly, there are eighteen muscles which join to the scapula and which are responsible for its imovement which creates the movement of your shoulder and upper arm.
The images below show the layering of the muscles, and how they attach to the bones, scapula (shown in green), the humerus and the clavicle.
Posterior view of the shoulder