The Crucial Role of the Shoulder Blade 

by | Mar 10, 2024 | Healthy posture & movement

A woman is getting her shoulder blade adjusted by a physiotherapist.

In the world of shoulder health, an often under-appreciated hero is the shoulder blade, scientifically known as the scapula. In this blog post, we will discuss the significance of the scapula in maintaining shoulder health, explore the connection between your back posture and the position of the scapula, understand the concept of the “force couple,” and even consider how the scapula’s position can influence the neck. 

The Shoulder Blade and Its Influence on the Shoulder

The scapula, positioned between the upper arm bone (humerus) and the collarbone (clavicle), is a small but crucial part of the shoulder. This triangular bone serves as an important anchor point for multiple essential shoulder muscles that are critical for facilitating shoulder mobility, preserving stability, and assuring proper shoulder function.

It forms the bony arch over the arm and the socket of the shoulder joint by joining to the posterior (back) side of the ribcage. This design is essential for obtaining a broad range of motion while reducing the risk of injury.

Here’s where it gets interesting, though: for your shoulder the function to its maximum potential and keep your injury-free it’s crucial that it must be in the proper alignment and move in unison with your arm. If your scapula remains stuck in a fixed position or moves uncontrollably, specific structures within your shoulder can bear excessive loads and become susceptible to injury. 

The Influence of Back Posture on Scapula Position

Maintaining good back posture is essential for keeping the scapula in its optimal position.

Normally your scapula should rest comfortably on your ribcage. However, when you slouch or round your back, it’s like your ribcage tilts downward. This makes your scapula move away from the ribcage and tip forward, almost as if they’re about to slip off. This change in their position can affect how your shoulders function and might lead to discomfort or issues.

When your back is straight and your shoulders are pulled back and down, the scapula is more likely to rest in its natural, stable position.

The Force Couple: Harmony in Shoulder Movement

The scapular force couple involves specific muscles around the scapula working together to produce smooth and efficient movement. Think of it as a team effort, with these muscles generating forces in different directions while maintaining stability and proper alignment of the scapula.

As you get ready to throw, for instance, the trapezius and Serratus anterior work together to produce scapular movement. The serratus anterior muscle is located along your ribs and slides the scapula forward, while the trapezius muscle (starting at the base of your skull, runs down your back) and pulls the scapula upward. This coordinated motion makes sure that your shoulder blade glides easily down your ribs, enabling your arm to produce a powerful and accurate throw. 

Unfortunately, the lower trapezius and serratus anterior often become weak due to factors like sedentary lifestyles, poor posture, and imbalanced training. This weakness leads to muscle imbalances around the shoulder, causing issues like the shoulder blade sticking out and changes in shoulder movement, making you more susceptible to shoulder injuries and discomfort.

To address these weaknesses and restore balance, it’s crucial to strengthen the lower trapezius and serratus anterior. Strengthening these muscles will help keep the shoulder blade close to the rib cage and ensure smooth movements during activities like punching and reaching.

How the shoulder blade position effects to neck

The position of your shoulder blade plays a crucial role in influencing the health and function of your neck. When the shoulder blade, is properly aligned and supported, it allows for optimal movement and stability in the neck region. 

However, if the shoulder blade is misaligned or lacking stability, it can lead to various issues in the neck. For instance, rounded or slouched shoulder blades can cause a forward head posture, placing excessive strain on the muscles, joints, and ligaments of the neck. On the other hand if the scapula is pulled up and back to much it can affect the alignment of your cervical spine. These abnormal positions can result in neck pain, stiffness, limited range of motion, and even headaches.


The shoulder blade is a silent powerhouse that plays a pivotal role in shoulder function and stability. Recognising the influence of back posture on scapula position emphasises the need for maintaining proper spinal alignment for optimal shoulder health. Additionally, understanding the force couples formed by the muscles around the scapula highlights the importance of balanced strength in this area. Out expert Physiotherapists will help you by incorporating targeted exercises and good posture habits into your daily routine, to ensure that your shoulder blade and its associated muscles are ready to support you in all your daily activities and athletic pursuits. 

Check out our Instagram account for easy-to-understand visuals that illustrate these important points.

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