A Stable Shoulder – The Secret to a Healthy Shoulder

Table of Contents

Related Articles

Sometimes all it takes is a painful shoulder for us to realise how much shoulder-arm movement we take for granted in our daily lives. From simple tasks such as wearing our clothes or carrying a bag. In this series, our shoulder specialist and principal physiotherapist Chye Tuan, explains the role of the scapula – commonly known as the shoulder blade, as the foundation for a healthy and stable shoulder.

Foundations of a Stable Shoulder – The Scapula

Our shoulder provides the arms with the widest range of movement in the body. The shoulder is flexible as it is largely made up of a combination of individual muscles and bones connected to one. This freedom of movement also means that the shoulder is inherently unstable. To provide stability, our body needs a platform for shoulder movements to work off – this platform is the scapula, commonly known as the shoulder blade.

stable shoulder scapula

Imagine the scapula as a floating platform on the upper back, held together by a set of muscles, then connected to ball joints on either side of the shoulder via ligaments and other soft tissue. The importance of stability in injury prevention has been spoken about in the past. Similarly, the stability of our shoulder is highly dependent on how strong a foundation the scapula provides.

Without a strong foundation, our body will find other ways and means to help stabilise the shoulder, such as recruiting other muscle groups. This often leads to injury down the road as these muscles are not naturally built to cope for long-term compensation for the weak shoulder muscles.

Imagine throwing a ball while standing on a surfboard above water. Now, compare this to performing the same task on firm level ground. You will find that different muscle groups are activated and the result of throwing a ball on firm ground will be better as compared to throwing it on unbalanced surfaces. Likewise, throwing a ball with a stable shoulder will have a better result as compared to an unstable shoulder.

What causes an unstable scapula?

Various reasons can cause an unstable scapula and often, these factors tend to be inter-related and seeking stability is imperative to avoid further injury.

Poor spinal posture

A slouched posture reduces the range of motion in the shoulder, making it less efficient and consequently, increasing strain in the shoulder muscles.

Tightened muscles

Rounded shoulders from tight chest muscles (pectorals) or overactive upper trapezius (close to the neck, which leads to neck strain) from hiking-up the shoulders due to tasks like operating a computer mouse.

Weakened muscles

The lower and middle trapezius are placed in a position where the muscles are not able to work efficiently, causing an inability to perform at optimum strength or function.

Trapezius Muscle

What can I do to get a stable shoulder?

In most cases, shoulder weakness and injury is attributed to and therefore rehabilitated with the neuro-muscular system – or what we’ve previously named “motor control”. Poor motor control causes poor shoulder positioning and movement, causing strain on some muscles and stretching out others.

An unstable scapula forces our neuro-muscular system to recalculate and communicate the revised coordination of various muscles to perform the functions required of the shoulder, further aggravating the situation. A clear understanding of how the shoulder works and through proper beyond-the-surface physiotherapy service, shoulder injuries can be treated. Muscular memory can also be corrected, avoiding future damage to such an important muscle group.

Want a stable shoulder? Experiencing shoulder pain? Click here to find out more about physiotherapy for shoulder pain relief and how Core Concepts can help

Like this article?

The “Secrets to a Healthy Shoulder” series will explore further into the shoulder, explain the primary functions, operative movement, and potential dangers so that the right treatment and rehabilitation can be sought. Like us on facebook to be updated on upcoming article releases!


  1. Mottram, S. L. (1997). Dynamic stability of the scapula. Manual therapy,2(3), 123-131.
  2. Paine, R. M., & Voight, M. (1993). The role of the scapula. Journal of Orthopaedic & Sports Physical Therapy, 18(1), 386-391.
  3. Voight, M. L., & Thomson, B. C. (2000). The role of the scapula in the rehabilitation of shoulder injuries. Journal of athletic training, 35(3), 364.
  4. Halder, A. M., Zhao, K. D., O’driscoll, S. W., Morrey, B. F., & An, K. N. (2001). Dynamic contributions to superior shoulder stability. Journal of Orthopaedic Research, 19(2), 206-212.