Scoliosis and pulmonary function.

The effect on pulmonary function of all three dimensions of the scoliotic deformity was analyzed with computer tomography in 33 patients with thoracic idiopathic scoliosis. Both static (total lung capacity [TLC], vital capacity [VC] and functional residual capacity [FRC] ) and dynamic volumes (forced expiratory volumes in one second [FEV-1]) were negatively correlated to the lateral deformity and, to a lesser degree, to rotation. Of the computer tomography variables reflecting kyphosis, the sagittal diameter was correlated positively to all lung volumes though negatively to the quotient FRC/TLC while the KLi was correlated positively to VC and FEV1. The conclusion is drawn that the Cobb angle gives the most accurate estimation of lung volume compromise and that operative treatment should aim of reducing the lateral dislocation of the vertebrae and at maintaining normal sagittal thoracic curve.