Effect of brace on the pulmonary function of female adolescent patients with idiopathic scoliosis

English Keywords:Adolescent idiopathic scoliosis  Pulmonary function test  Brace  Female

English Abstract:

  【Abstract】 Objective：To investigate the effect of brace on the pulmonary function of female adolescent patients with idiopathic scoliosis（AIS）.Method：From February 2001 to December 2009，a total of 283 female AIS patients underwent correction surgery in our hospital.Preoperative pulmonary function tests（PFTs） were evaluated.The predicted value and actual value of forced vital capacity（FVC），forced expiratory volume in one second（FEV1） as well as the ratio of actual and predicted value of FVC（FVC%） and FEV1（FEV1%） were recorded respectively.The patients were classified into two groups according to brace-wearing：group A，preoperative brace，80 cases；group B，no preoperative brace，203 cases.The PFTs between the 2 groups were compared.Multiple linear regression analysis with respect to age，height，coronal Cobb angle of the major curve，number of the involved vertebrae in major curve，sagittal Cobb angle of the thoracic curve，everyday and total brace-wearing time，FVC% and FEV1% were measured finally.Result：The predicted values of FVC in group A and group B were 3.23±0.40L and 3.20±0.40L，and the predicted values of FEV1 were 2.76±0.40L and 2.73±0.30L respectively.No significant difference was noted between 2 groups（both P>0.05）.The actual values of FVC in group A and group B were 2.58±0.60L and 2.72±0.60L，and the actual values of FEV1 were 2.34±0.50L and 2.49±0.50L respectively.The FVC% in group A and group B were （80.3±16.5）% and （85.4±16.5）%，and the FEV1% were（85.6±18.4）% and（91.3±16.9）% respectively.The patients in group A had significantly lower FEV1，FVC% and FEV1%（all P<0.05） than group B，especially in patients with primary thoracic curve（173 cases）（P<0.05），however the contrary in patients with primary thoracolumbar/lumbar curve（110 cases）（P>0.05）.Group A showed significant positive correlations between sagittal Cobb angle of the thoracic curve and FVC% as well as FEV1%（both P<0.05），while negative correlation between total brace time and FEV1%（P<0.05）.The age，height，coronal Cobb angle of the major curve，number of the involved vertebrae of major curve，everyday brace-wearing time（8-23h，average 18.7h） were not associated with FVC% and FEV1%（all P>0.05）.Conclusion：Preoperative brace decreases FVC% and FEV1% in female thoracic AIS. The total brace-wearing time and sagittal Cobb angle of thoracic curve may be the risk factors of FVC% and FEV1%.