Scapular Stabilizers – An Often Neglected Group of Muscles
What Are The Scapular Stabilizers?
These muscles that surround the scapula (shoulder blade) and are along with the rotator cuff (infraspinatus, supraspinatus, teres minor, subscapularis) are crucial in maintaining normal shoulder function and biomechanics.
The muscles that make up the scapular stabilizers group are the:
- Serratus Anterior
- Trapezius muscles: Upper/Middle/Lower
- Levator Scapula
These muscles work synergistically with the deltoid and rotator cuff muscles to upwardly or downwardly rotate the scapula while the shoulder joint/arm is moving overhead, behind the back or reaching away from your trunk.
Take for example a baseball pitcher or competitive swimmer. Their shoulders rotate hundreds to thousands of times during a season and preseason. This can take quite a toll on their shoulders if they are not properly trained.
These muscles work synergistically to maintain proper scapular position and motor control with arm movements such as shoulder abduction, shoulder flexion, external/internal rotation, and shoulder extension.
The Scapular Stabilizers And Shoulder Function
The scapular stabilizers provide strength, joint stability and prevent impingement of the shoulder joint complex.
The muscles that comprise the scapular stabilizers are the:
- Serratus anterior– Which upwardly rotates the scapula.
- Trapezius – Upper fibers that elevate and upwardly rotate the scapula.
- Middle fibers – Adduct or retract the scapula.
- Lower fibers – Which depress and rotate the scapula.
- Levator Scapula and Rhomboids.
The shoulder joint complex is inherently at risk for instability. The glenohumeral (GH) joint is a ball and socket joint. The problem is that the ball or the humeral head goes into a very shallow socket of the glenoid fossa.
You will be at risk for shoulder injury if not properly supported by strong muscles – those muscles being the rotator cuff and scapular stabilizers.
Impingement can occur when the shoulder joint or glenohumeral (GH) hits the top of the scapula or acromion causing pain and inflammation.
If left untreated, it can lead to muscle inflammation or worse rotator cuff tears. Impingement can be caused by too much laxity in the GH joint or conversely an excessively stiff shoulder.
Shoulder Pain And The Scapular Stabilizers
Many of the patients that come into Paspa Physical Therapy with shoulder pain often have weak and under-developed scapular stabilizers. Clients work out the biceps, triceps, pectoralis major, and deltoid, but forget the look behind their backs. The scapular stabilizers are there and need to be exercised!
Dyskinesis or abnormal movement patterns occur leading to pain and dysfunction. In the clinic, we see many overuse injuries related to muscle weakness, not only of the rotator cuff muscles but more often of the scapular muscles.
You will find that training the scapular stabilizers will lead to improved athletic shoulder function and performance and a healthier pain-free shoulder joint.
To learn more about strengthening the scapular muscles and rotator cuff contact Paspa Physical Therapy.