Theserratus anterioris a fan-shaped muscle that attaches your shoulder blade, known as yourscapula, to your rib cage.
The muscle helps to move your scapula in various directions and is essential for proper shoulder function.
It then courses around the side of your rib cage and underneath your scapula.
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There, it inserts along the medial border of your scapula.
The serratus anterior is innervated by the long thoracic nerve.
You have two serratus anterior muscles, one on each side of your body.
What Do the Serratus Anterior Muscles Do?
The serratus anterior muscle protracts the shoulder blades.
This means that they pull them forward around your rib cage.
The inferior and superior aspect of the serratus also helps to stabilize your shoulder blade against your rib cage.
This occurs during normal breathing.
Thus, the serratus anterior muscles are considered secondary muscles of respiration.
Although rare, serratus anterior myofascial pain syndrome (SAMPS) is another potential cause.
Injury to the serratus can result in a condition called a winged scapula.
This manifests as a visual bump in your back where your shoulder blade resides.
A rib fracture can cause the muscle tissue of the serratus to pull away, resulting in anavulsion fracture.
This can be a painful injury and limits the function of the serratus anterior.
Sometimes, serratus anterior weakness and winging of the scapula can occur for no apparent reason.
A condition known asParsonage-Turner Syndromemay affect your brachial plexus and the long thoracic nerve.
This brachial neuritis may cause weakness in your serratus and manifest as the telltale scapular winging.
An injury to your shoulder or rotator cuff may also cause scapular winging.
Conditions like rotator cuff tear or ashoulder separationmay cause pain and inhibition of the muscles that support your shoulder.
To do this test:
Have someone watch the position of your shoulder blades.
If one shoulder blade wings out, there may be weakness in your serratus anterior on that side.
What Are the Symptoms of Serratus Anterior Pain?
Pain associated with the serratus anterior muscle may occur in the chest, back, and arm.
It may be perceived as burning or stabbing in nature.
In some cases, the pain may radiate down to the fingers.
Working with a physical therapist can help you recover after an injury to your serratus.
An injury here can cause pain, limited motion, scapular winging, and difficulty using your arm normally.
Understanding the anatomy and function of your serratus anterior can help you properly rehab it after an injury.
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