Spirometric pulmonary function tests before and after surgical correction of idiopathic scoliosis in adolescents.

Severe scoliosis causes a deterioration in cardiopulmonary function. The effect of surgical correction on this is variable. We studied the forced vital capacity [FVC) and forced expiratory volume in one second (FEV1) before and after surgical correction in 30 adolescents with idiopathic scoliosis and the results are expressed as a percentage of the predicted normal values using 101 children as controls. A negative correlation was noted preoperatively between the magnitude of the curve and FVC and FEV1. Surgical correction of the curve was done with a Harrington rod in 17 patients followed by cast and brace immobilisation for one and a half years. In the remaining 13 patients the Harrington rod was supplemented with sublaminar wires (SSI) to eliminate the use of an orthoses. All patients had a posterior spinal fusion. Our study showed that there was an improvement in the spirometric values post-operatively but this was not statistically significant. This improvement was similar in both groups of patients. Further studies, for a longer period and of other indices of pulmonary function are required.