Key Takeaways
- Uneven shoulders may be caused by posture, repeated one-sided activities, muscle imbalance or structural changes such as scoliosis.
- Seek medical assessment if the asymmetry becomes more noticeable, causes pain or weakness, or appears with an uneven waist, rib prominence or trunk shift.
- Doctors may examine the shoulders, spine, pelvis, muscle function and reflexes, with standing X-rays used when a structural curve is suspected.
- Mild cases may be managed with monitoring, activity changes and physical therapy, while growing teenagers with scoliosis may require bracing.
- Surgery is generally considered only for progressive deformity, instability, nerve compression or symptoms that continue despite non-surgical care.
Introduction
Have you noticed that one of your shoulders is sitting higher than the other? Having uneven shoulders can be unsettling, but it may not necessarily be a sign of something serious. In some cases, it may be caused by poor posture, a muscle imbalance, or structural changes within the spine.
This article breaks down the possible causes of uneven shoulders, the signs you should look out for, and how our doctors at Achieve Spine And Orthopaedic Centre determine whether treatment is needed.
Possible Causes of Uneven Shoulders
1. Poor Posture
Certain postural habits, such as slouching, leaning to one side or looking down at a screen for long periods, can place uneven strain on the muscles and joints around the neck, shoulders and upper back.
Over time, the body may adapt to these positions. Some muscles may become tighter while others weaken, causing one shoulder to sit higher or further forward than the other.
2. Favouring Your Dominant Side
Activities that repeatedly use one arm can cause the two sides of the body to develop differently. This may happen when carrying a bag on the same shoulder, lifting objects with the same arm or repeatedly leaning on one side.
Sports such as baseball, volleyball and tennis can also place greater demands on the dominant arm1. Over time, repeated one-sided movements may affect the position and movement of the shoulder blade, causing it to rotate or tilt differently
3. Scoliosis
Certain types of spinal deformities, such as scoliosis, may also affect shoulder height. Scoliosis is an abnormal sideways curvature of the spine that is often accompanied by rotation of the vertebrae. As the spine curves and twists, one shoulder or shoulder blade may appear higher or more prominent than the other2.
Other signs may include uneven hips and waist, a visible trunk shift, or one side of the rib cage becoming more prominent when bending forwards.
When Should You Seek Medical Help for Shoulder Asymmetry?
A slight difference in shoulder height is common and does not always require treatment, particularly if it has been present for years and is not causing any symptoms.
However, we recommend seeking a medical assessment if your uneven shoulders are becoming more noticeable or are accompanied by other symptoms, such as:
- Persistent neck, shoulder or upper back pain
- Numbness, tingling or weakness in the arms
- Reduced shoulder or spinal movement
- One shoulder blade or one side of the rib cage becoming more prominent
- An uneven waist or one hip sitting noticeably higher than the other
- A visible change in posture over several months or years
- Shoulder asymmetry that develops after a fall or other injury
What Our Doctors Look Out For
1. Assessing Your Standing Alignment
Our doctors first compare the position of your shoulders, shoulder blades, waist, and hips. We also look for signs such as a trunk shift, uneven waistline, or one shoulder blade appearing more prominent.
2. Observing Movement and Flexibility
You may be asked to bend forwards, raise your arms, or move your neck and spine. This helps us assess flexibility, shoulder blade movement and whether there is any rib or lower-back prominence.
3. Checking the Pelvis and Lower Limbs
The pelvis and legs may also be examined, as a tilted pelvis or leg length difference can affect the position of the upper body.
4. Screening for Nerve Involvement
If you have pain, numbness, or weakness, our doctors may test your strength, sensation and reflexes to look for possible nerve involvement.
5. Determining Whether Imaging Is Needed
Your doctor will ask when the asymmetry was first noticed, whether it has changed and whether you are still growing. If a structural spinal curve is suspected, a standing X-ray of the entire spine may be recommended to measure its location and severity using the Cobb angle.
How Spine-Related Shoulder Asymmetry Is Treated
If the asymmetry is caused by scoliosis, your spinal specialist may recommend a structured treatment plan. This may include:
1. Monitoring and Physical Therapy
Mild or flexible imbalances may not require immediate intervention. Treatment may include:
- Monitoring the shoulder and spinal alignment over time
- Adjusting activities that place uneven strain on the body
- Targeted physical therapy to improve mobility and muscle control
- Exercises to manage stiffness, fatigue and discomfort
These measures may improve function and posture, but they do not usually correct a fixed structural spinal curve.
2. Bracing for Growing Teenagers
For teenagers who are still growing, bracing may be recommended depending on the Cobb angle and the risk of the curve progressing3.
The main aim of bracing is to slow or prevent further progression during growth. It is not intended to make the spine completely straight. A scoliosis treatment plan should therefore focus on how the curve is changing, rather than shoulder appearance alone.
3. Surgery for Progressive Spinal Deformity
We may consider surgery when there is:
- A substantial or worsening spinal curve
- Significant imbalance or instability
- Persistent symptoms despite non-surgical treatment
- Nerve or spinal cord compression
- Increasing difficulty with movement or daily activities
Corrective surgery may involve spinal fusion and instrumentation, using rods, screws or other implants to realign and stabilise the affected part of the spine. The exact approach depends on the location, flexibility and severity of the curve, as well as the patient’s age, overall health and treatment goals.
4. Minimally Invasive Surgery for Adolescent Idiopathic Scoliosis (AIS)
For selected patients with adolescent idiopathic scoliosis (AIS), a minimally invasive approach may also be considered. This uses several smaller incisions and works between the muscles rather than exposing a long section of the spine through one larger incision.
Minimally invasive scoliosis surgery may reduce muscle disruption and blood loss, although it can take longer to perform and is not suitable for every curve. The choice depends on factors such as the curve pattern, severity and flexibility, as well as the teenager’s stage of growth and overall health. However, we may still recommend conventional open surgery for more extensive, rigid or complex deformities.
Conclusion
On their own, uneven shoulders do not necessarily point to a serious problem. The difference may come from posture, muscle imbalance or repeated use of one side of the body. What matters more is whether the asymmetry is changing, causing symptoms, or appearing together with other signs.
At Achieve Spine And Orthopaedic Centre, our doctors take the time to understand what is driving the asymmetry and how it is affecting your movement, comfort and daily activities. Treatment is then tailored to the underlying condition, whether that means monitoring, physical therapy or surgical care.
Where surgery is appropriate, our team offers a range of conventional, minimally invasive and endoscopic spine procedures, including selected ambulatory surgeries designed to minimise tissue disruption and support an earlier return to daily activity.
For more information on our approach, visit our website today.
References:
1. Oyama, S., Myers, J. B., Wassinger, C. A., Daniel Ricci, R., & Lephart, S. M. (2008). Asymmetric resting scapular posture in healthy overhead athletes. Journal of athletic training, 43(6), 565–570. https://doi.org/10.4085/1062-6050-43.6.565
2. Nikouei, F., Ghandhari, H., Ameri, E., & Mokarami, F. (2022). Shoulder Imbalance in Adolescent Idiopathic Scoliosis: A Systematic Review of the Current State of the Art. The archives of bone and joint surgery, 10(12), 992–1003. https://doi.org/10.22038/ABJS.2022.64282.3086
3. Zhu, Z., Xu, L., Jiang, L., Sun, X., Qiao, J., Qian, B. P., Mao, S., & Qiu, Y. (2017). Is Brace Treatment Appropriate for Adolescent Idiopathic Scoliosis Patients Refusing Surgery With Cobb Angle Between 40 and 50 Degrees. Clinical spine surgery, 30(2), 85–89. https://doi.org/10.1097/BSD.0b013e3182a1de29
