[Pulmonary function assessment in juvenile idiopathic scoliosis managed with posterior instrumentation with a sublaminar hook system].

INTRODUCTION

Scoliosis is a spine deformity diagnosed using Cobbs method when the AP X-ray view shows an angulation greater than 10º. Scoliosis exceeding 50º results in restrictive pulmonary alterations. Surgical management improves the angulation and the pulmonary restrictive process. The pre- and post-operative pulmonary function values were compared using spirometry.

MATERIAL AND

METHODS

27 patients of both genders, ages 11-15 years, underwent corrective surgery using posterior instrumentation with sublaminar hooks, rods and posterolateral arthrodesis. Spirometry was done preoperatively and six months after the surgery. Patients without a postoperative spirometry and/or a postoperative episode of pulmonary infection were excluded. The pre- and postoperative Cobb index was calculated. Spirometry: lung function at forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). Descriptive statistics, Student t test.

RESULTS

Females, 78%; males, 22%; 13.7 ± 1.22 years. Cobb method 40 - 110º, preoperative angle 64.48 ± 17.79º and postoperative angle 30.44 ± 10.90º. There were no 0º values. Lung function: preoperative FVC for the values of the scoliosis curve (p 0.0001) and significant marginal FEV1 (p = 0. Baseline: 40.6-122.0%, mean: 76.3 ± 18.8%, postoperative: 40.75-112.6%, mean: 76.5 ± 16.8%. Preoperative FEV1: 39.8-111.59%, mean: 73.9 ± 16.8%, postoperative: 42.86-120.79%, mean: 69.7 ± 16.5. The difference was statistically significant, 0.064).

CONCLUSIONS

The sublaminar hook system with a posterior approach provides improvement of the idiopathic scoliosis curve of adolescents assessed with the Cobb method. It stops the progression of lung function impairment, with a significant improvement in forced expiratory volume in one second.