[Factors affecting the preoperative pulmonary function test in patients with scoliosis: a retrospective evaluation of 108 cases]

To evaluate factors affecting the preoperative pulmonary function in patients with scoliosis.

Preoperative pulmonary function texts (PFTs) were performed on 108 patients with spinal deformities, 17 males and 91 females, aged (15.2 +/- 5.36) (7 - 27), 70 being with idiopathic scoliosis (IS) and 38 with congenital scoliosis (CS). The parameters affecting the preoperative pulmonary function were analyzed.

The Cobb angle of scoliosis was negatively correlated with vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), forced expiratory flow between 25% to 75% of forced vital capacity (FEF25-75), maxima mid-expiratory flow (MMEF), and maximal ventilatory volume (MVV), and not correlated with minute ventilation (MV) and ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC%). The impairment of lung functions was more severe in the CS patients than in the IS patients. The degrees of impairment of lung functions in the groups of the Cobb angle > or = 90 degrees , with the number of vertebrae involved > or = 7, with the age of onset < 10, and of cephalad location of the curve were more severe than those of the groups with different corresponding parameters.

The deterioration of pulmonary function mainly depends upon the age of onset, Cobb angle, location of the apex vertebra and the number of involved vertebrae.