Scoliosis is a three-dimensional distortion of the rib cage, typically producing a reduction in lung function, caused by stiffness of the chest wall and decreased strength of the respiratory muscles (8). However, the present study showed a negative relationship between the degree of the Cobb angle, which indicates spinal deformity, and lung function, although the relationship was not statistically significant. Some studies have reported an inverse relationship between spinal deformity and lung function. Vitale et al. found that the degree of thoracic curves was negatively correlated with FEV1. There was also a trend toward significant negative correlations between thoracic curves and FVC. Patients with larger thoracic curves had lower lung function as measured by FEV1 and FVC (2). The magnitude of the thoracic curve, the number of vertebrae involved in the thoracic curve, thoracic hypokyphosis, and coronal imbalance had a minimal but significant effect on lung function. Although these four factors were associated with an increased risk of moderate or severe pulmonary impairment, they explained only 19.7%, 18.0%, and 8.8% of the variability observed in FVC, FEV1, and total lung capacity (TLC), respectively. (1). . Respiratory failure has been observed in untreated patients with idiopathic scoliosis who had a large scoliotic angle and low vital capacity, especially in early onset of scoliosis (9). Scoliosis greater than 40 degrees and kyphosis greater than 50 degrees were correlated with increased pain and decreased FVC. The reduction in FVC was also related to the stiffness of the curve (10). Scoliosis angle was one of four characteristics of spinal deformity associated with a reduced percentage of vital capacity; greatest number of vertes......center of the card......monastic function. Conversely, further decreases in lung function may be associated with anterior spinal fusion through an open thoracotomy approach (1). Pulmonary compromise due to spinal deformity remains one of the indications for surgery. Pulmonary function tests are useful in the preoperative evaluation of patients with adolescent idiopathic scoliosis. Impaired lung function was observed in more severe spinal deformities, more proximally located curve, and in older patients. Pulmonary compromise due to spinal deformity remains one of the indications for surgery. Pulmonary function tests are useful in the preoperative evaluation of patients with adolescent idiopathic scoliosis. Impaired lung function was observed in more severe spinal deformities, more proximally located curve, and in older patients.