Reviewed by Dr. Bin Cai

Dr. Cai focuses on complex chest wall deformities and infections. He tailors surgical techniques, incision design, and postoperative care to each patient, aiming for optimal correction and infection control.

Many individuals first notice straight back syndrome through a physical finding: the disappearance of the normal physiological curvature of the thoracic spine (a lack of the natural curve in the back). While many individuals are concerned about the aesthetic changes, a large proportion experience physical discomfort without understanding its underlying cause.

Straight back syndrome is a rare and often misunderstood condition; research about it is limited. Correspondingly, the treatment options available in most medical centers are insufficient, leaving many patients without a clear direction.

What is Straight Back Syndrome?

Straight back syndrome is an extremely rare spinal deformity, and its exact cause remains unclear. It was first reported by Rawlings in 1960^[1].

The main feature of straight back syndrome is the disappearance of the normal kyphotic curvature of the thoracic spine, leading to a shortened anteroposterior diameter of the chest and restricted cardiac activity^[2].

(In a healthy spine, the thoracic region possesses a natural outward curve that creates sufficient volume within the chest cavity. When this curve is absent, the spine becomes abnormally straight—a condition known as thoracic hypokyphosis.)

How It Differs From A Normal Spine

· Normal Thoracic Spine: outward curvature, adequate  space between the thoracic spine and the anterior chest wall

· Straight Back Syndrome Spine: minimal or absent curvature, shortened anteroposterior diameter of the thoracic cavity

· Direct Consequence: Reduction in mediastinal space (the central compartment of the thoracic cavity), resulting in compression of the heart and other mediastinal contents (such as esophagus, thymus, great vessels, trachea, and essential nerves).

Straight Back Syndrome Symptoms

In patients with straight back syndrome, the primary risks arise from compression of mediastinal structures, among which the heart is the most significantly affected.

(The heart occupies most of the mediastinal space. Due to its limited mobility, it is particularly susceptible to compression.)

1. Common symptoms following heart compression:

Palpitations, Arrhythmias, Precordial pain, etc.

2. Other common symptoms:

Chest tightness, Shortness of breath, Dyspnea, etc.

3. Patients may also experience, when the trachea is severely compressed:

Severe airway obstruction.

Additionally, certain anterior chest wall deformities, such as pectus excavatum and flat chest,  frequently coexist with straight back syndrome.

Further Reading:

What is Pectus Excavatum? Your Top FAQs Answered

What Do People with Flat Chest Deformity Feel Like?

Diagnosis of Straight Back Syndrome

The diagnosis of straight back syndrome includes physical examination and imaging studies. In addition, cardiac-related evaluations may also be involved.

• Physical examination reveals the key sign in straight back syndrome patients: loss of normal physiological curvature of the thoracic spine.

  
  

• Imaging studies, such as X-rays, chest CT scans, and 3D reconstruction, help assess abnormal spinal curvature and narrowing of the space between the thoracic spine and anterior chest wall.

  
  

• Cardiac evaluations are essential, as straight back syndrome often affects the heart, causing various functional abnormalities. These tests rule out structural heart diseases (e.g., congenital heart disease, rheumatic heart disease, coronary artery disease, great vessel disorders).

  
  

Additionally, if significant airway obstruction symptoms are present, airway evaluation is needed to exclude other causes of obstruction.

Straight Back Syndrome Treatment

For most patients with straight back syndrome, conservative symptomatic treatment is sufficient, and surgery is usually not required. Surgical intervention targeting the thoracic spine or the anterior chest wall is considered only when conservative treatments fail, symptoms are severe, or pectus excavatum/flat chest coexists.

However, because reshaping the thoracic spine remains extremely challenging, no safe and effective surgical technique has yet been established.

In view of this limitation, ICWS has proposed an innovative surgical concept: remodeling and reconstructing the anterior chest wall (using digitalized materials or the MatrixRIB) to slightly protrude the chest wall forward, thereby increasing overall thoracic cavity volume and relieving compression on mediastinal structures.

It should be noted that this surgical approach is relatively invasive and may be associated with complications such as displacement or compression of the heart, major vessels, and trachea. Thus, it is suitable only for patients with severe symptoms that are unresponsive to conservative therapy.

Successful Surgical Cases:

The World’s First Successful Chest Wall Reconstruction Surgery for A Patient with Flatback Syndrome

Surgery for A 4-year-old Child with Straight Back Syndrome and Chest Wall Deformity

ICWS

ICWS successfully performed the world’s first chest wall reconstruction surgery for a patient with straight back syndrome and continues to advance the treatment of rare chest wall disorders through ongoing surgical innovation.

We advise that early medical evaluation should be sought by anyone with symptoms or concerns about straight back syndrome treatment. A careful assessment can help determine the safest, most personalized approach for straight back syndrome.

References:

[1] Rawlings, M. S. (1960). The “straight back” syndrome. The American Journal of Cardiology, 5(3), 333–338. https://doi.org/10.1016/0002-9149(60)90080-1

[2] Kong, M., Pei, Z., Zhang, X., Du, Q., Tang, Q., Li, J., & He, G. (2023). Related mechanisms and research progress in straight back syndrome. World Journal of Cardiology, 15(10), 479–486. https://doi.org/10.4330/wjc.v15.i10.479