Written by Or rather, how NOT to break down your shoulder. Today’s post is Part 1 where we’ll examine the shoulder girdle, mainly the scapula. Part 2 will look at the glenohumeral joint (the humerus and scapula together) and the muscles acting on that. Finally, Part 3 will talk about ways to maintain/improve shoulder health and strength. I’m a visual person so there are lots-o-pictures in this post.
The Glenohumeral Joint and Scapula
Today we’re focusing on the scapula, aka the shoulder blade. It is a wild and crazy bone that “floats” atop the ribcage. However, there’s plenty of muscles holding that sucker down:
Levator scapula: (left) attaches to the superior aspect of the scapula; it elevates (shrugs upwards) the scapula…pretty much what everyone does all day long, especially in traffic.
Next up are our rhomboids major and minor. These little guys attach to the medial border (closest to the spine) of the scapula and also connect to the lower cervical and upper thoracic spine. They both elevate and adduct the scapula (like when you pinch a pencil between your shoulder blades). And I can tell you from personal experience, these two often get stretched and weak because we slouch so much during the day. As we learn more about scapular motion in later posts, we’ll see how this is not a helpful thing when we’re trying to keep our shoulders pain-free.
Then of course we have the trapizius. Most people are familiar with this one: 
There are 3 parts to this ginormous muscle. The upper portion attaches to lower cervical spine, the distal (far end) of the collar bone and the scapula’s acromion process. It helps the levator scapula with elevation. The mid- and lower portions attach to the scapula along the medial border and the thoracic spine. This helps with depression, or pulling the scap down. In most people, the upper trapizius is way over active (which is why everyone accumulates knots up there. Relax!) while the mid and lower traps are weak and under active. In Part 3, I’ll go over ways to help correct this imbalance.
From the front, we have the pec minor,
a sneaky little bugger that attaches to the coracoid process and the ribs; it can pull the scapula “over” the shoulder. It also abducts (pulls away from the spine) the scapula. This one is also usually tight in the slouching population (aka, everyone) and can really screw with scapular rhythm.
Last, but certainly not least, one of my favorite muscles, the serratus anterior. 
A super fun muscle group (it looks like shark fins) that connects along the medial border of the scapula from the front/inside, opposite of the rhomboids. They work in conjunction with the rhomboids to help keep the scapula close to the rib cage and gliding smoothly.
But why is this important? All these muscles attach to and wriggle the scapula around (or hold it steady) ultimately to allow a greater range of motion with the glenohumeral joint. Without this ROM, we wouldn’t be able to press things overhead, do push ups, frantically wave our arms in a futile attempt to get someone’s attention…etc.
Smooth scapular motion is vitally important for maintaining pain-free shoulder movements. In the next post, I’ll hit the glenohumeral joint and it’s corresponding muscles and then tie in how it works with the scapula to produce all those lovely motions we like to do. So… you have a day to research more about our amazing shoulders, or you can patiently wait for Part 2 on Thursday.
*sigh* if only I knew about the glenohumeral joint.
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