Abstract
Object：To evaluate the changes in pulmonary function caused by preoperative halo-pelvic traction (HPT) in patients with severe and rigid thoracic scoliosis, and find out the factors influencing the improvement of pulmonary function HPT.
Method: According to the inclusion and exclusion criteria, we selected patients with severe and rigid thoracic scoliosis who underwent preoperative HPT in our hospital from 2022.1 to 2023.1. Spinal parameters including main thoracic Cobb angle, thoracic kyphosis, T1-T12 distance, and T1-S1 distance in standing whole spinal coronal and sagittal film before traction and after traction were evaluated, as well as pulmonary function test (PFT) results included FVC, forced expiratory volume in 1 second (FEV1), and the measured FVC and FEV1 values as a percentage of the predicted values (FVC%, FEV1%). Total lung volume (TLV) was measured by pre-traction and post-traction CT images.
Results: Thirty patients with severe and rigid scoliosis and severe pulmonary impairment were included in the study. The mean age of the patients was 25.8±6.93 years. The average duration of traction was 3.7±1.28 months. The main thoracic Cobb angle and thoracic kyphosis decreased from pre-traction 140.8±19.9° and 124.9±46.4° to post-traction 98.6±20.3° and 89.5±43.5°，respectively. T1-T12 distance increased from 139.0±32.7 mm before traction to 195.1±36.1 mm after traction, while T1-S1 distance increased from 246.7±57.3 mm to 346.0±54.2 mm. The FVC and FEV1 improved from 1.09±0.44 L, and 0.90±0.38 L to 1.35±0.42 L, and 1.17±0.37 L after traction, respectively. The FVC and FEV1 improved significantly as well as FVC% and FEV1%. The pre-traction and post-traction TLV (1706.0±584.1ml and 2097.4±662.2ml, respectively) were significantly difference. The variation in T1-T12 distance and T1-S1 distance exhibited correlation with variation in FVC and FVC% before and after traction. Correlation was also observed between the variation of Cobb angle and total lung volume.
Conclusion: The application of HPT is a safe and effective method for improving pulmonary function in patients with severe and rigid thoracic scoliosis. The improvement of FVC and FVC% were significantly correlation with the changes of T1-T12 distance and T1-S1 distance.