The Forgotten Muscle of the Shoulder: Serratus Anterior

While much focus and attention gets placed on strengthening the rotator cuff to maintain healthy shoulders, a muscle often gets forgotten on the path to healthy shoulders. That forgotten muscle is the serratus anterior.

What is the Serratus Anterior?

The Serratus Anterior is a muscle that originates from the side/front of the chest wall and attaches to the front of your shoulder blade. The muscle is supplied by the lower nerves of the neck (C5-C7).

As you can see from the picture to the right, the serratus anterior has a serrated knife-like appearance and is noticeable in muscle-defined individuals.

physio working on shoulder mobility
therapist working on sore shoulder

The Serratus Anterior has a few different functions:

  1. It helps anchor the shoulder blade against the rib cage. This anchoring gives the shoulder blade a good foundation for stability and control of the shoulder joint.
  2. It helps rotate the shoulder blades upwards when lifting the arms overhead.
  3. It helps with breathing, given its attachments to the rib cage.

Why is the Serratus Anterior Important?

First, the Serratus Anterior provides some necessary support for your shoulder blades to stay in a neutral position with your arms by your side. If your Serratus Anterior muscle is weak and lengthened, it can increase the shoulders’ rounding, and your shoulder blades may sit further away from your spine.

Second, your Serratus Anterior helps to bring your arms overhead. When you lift your arms overhead, most of that movement comes from the shoulder joint, but a portion of the motion comes from the shoulder blade. When the shoulder blade doesn’t rotate enough through overhead movements, it puts more strain on the shoulder joint. This strain can result in excess stress being placed on the AC joint (where your collarbone and shoulder blade connect) and on the tendons of the rotator cuff.

The most common sign of Serratus Anterior dysfunction is winging of the scapula. This winging can come from an issue with the nerve supplying the muscle or a weak or lengthened Serratus Anterior muscle.

Signs That Your Serratus Anterior May Have Challenges

Here are a few telltale signs that tell you that your Serratus Anterior may be struggling:

  1. You may notice when you look at yourself in the mirror (side view) that you see a fair amount of your shoulder blades
  2. You may find it a struggle to get your arms overhead easily and effortlessly
  3. You may have someone observe that your shoulder blades are winging in standing or when doing exercises such as a forward plank or a push-up.
  4. You may experience AC joint tenderness or chronic “rotator cuff tendinitis” that doesn’t seem to go away.

If you answer yes to any of these telltale signs, booking an appointment with one of Innovation Physical Therapy’s experienced physiotherapists would be most beneficial. Given that the shoulder blades are visually out of sight for us, it can be challenging to understand how well they function with different movements and exercises.

Exercises for Your Serratus Anterior

To get you started with engaging your serratus anterior, we wanted to provide you with two exercises:

  1. The Punch Out

Lying on your back, straighten your arm with a small weight (1-5 pounds) and punch your fist toward the sky. Slowly lower the arm while keeping the elbow straight. Avoid using your neck or chest muscles and focus on punching out from the shoulder blade—repeat 10-15x.

  1. The Push-up Plus

In the push-up position, perform a push-up, and give an extra little push through your shoulder blades on the way back up. Avoid rounding your mid back or lifting your hips when doing this.

What Now?

If you answered “yes” to any of the telltale signs mentioned above or are experiencing shoulder pain with activities or sleeping, you’ll want to have a thorough assessment. Physiotherapists are movement experts trained to diagnose and treat movement-related problems of the shoulders and the body.

To book an appointment with one of Innovation Physical Therapy’s experienced physiotherapists, call one of our five clinics throughout Edmonton, including RiverbendBelvedereNamaoor our newest clinic in Southgate Centre.