[Pulmonary function in adolescents with idiopathic thoracic scoliosis before and after surgical correction]

The purpose of this study has been to establish pulmonary function improvement achievable by surgical correction of the scoliotic curve as compared with the achieved curve correction. The study comprised two distinct groups of patients with an average age of 15 years with idiopathic thoracic scoliosis. The first group of 33 patients were treated surgically: an average Cobb angle of 72 degrees was postoperatively reduced to 32.6 degrees. The second group of 30 patients of the same age with an average Cobb angle of 33 degrees who were not treated surgically. Cardiorespiratory function parameters were tested--preoperatively and 24 months after surgery--by spirometry and plethysmography, arterial blood gas analysis, and the exercise tolerance test. The results of the tests have demonstrated that correction of the scoliotic curve improves pulmonary function: however, the improvement does not match the degree of achieved scoliotic curve correction. Statistical analysis surgically and nonsurgically treated patients with the same degree of spinal curvature disclosed a difference in cardiopulmonary function--specifically, ther VC and PaO2 variables--to the advantage of nonsurgically treated patients. This observation suggests partial irreversibility of ventilation and perfusion in surgically treated patients.