Straight back syndrome, also known as flatback syndrome, refers to the disappearance of the normal physiological curvature of the thoracic spine, which results in a shortened anteroposterior diameter of the chest. This reduction not only decreases the effective volume of the thoracic cavity but also compresses the mediastinal contents, leading to a series of changes, such as compression and displacement of the heart and major blood vessels.

The cause of straight back syndrome remains unclear, but it may be related to genetic factor or abnormal thoracic vertebrae development during the embryonic stage.

Common symptoms of straight back syndrome include chest tightness, shortness of breath, palpitations, arrhythmias, precordial pain, and breathing discomfort. Some patients may also experience severe airway obstruction. Additionally, patients with straight back syndrome often have accompanying chest wall deformities such as pectus excavatum and flat chest.

Diagnosis involves assessing the patient’s clinical manifestations and physical signs, along with imaging examinations such as X-ray, chest CT scan, and 3D reconstruction.

For most patients with straight back syndrome, conservative symptomatic treatment is sufficient and surgery is generally not required. However, in more severe cases—for example, when the airway is severely compressed and normal breathing is affected, or when accompanied by chest wall deformity such as pectus excavatum or flat chest that exacerbate the compression on the mediastinal contents—surgical intervention becomes necessary. 

Given the limitations of existing surgical methods in altering spinal curvature, the institue of chest wall surgery (ICWS) has proposed an innovative approach: reconstructing the anterior chest wall using digital material or MatrixRIB to create a slight anterior convexity, thereby increasing mediastinal space and reducing the compression. However, this method is highly invasive and only suitable for patients with severe symptoms.

For patients with straight back syndrome who also have pectus excavatum or flat chest, conventional surgical correction of the chest wall deformity can be adopted to significantly increase mediastinal space and relieve the compression.