Does pulmonary function improve after surgical correction of adult idiopathic scoliosis?

Evaluation of Pulmonary Function After Halo-Pelvic Traction for Severe and Rigid Kyphoscoliosis Utilizing CT with 3D Reconstruction

BACKGROUND

The purpose of the present study was to evaluate changes in pulmonary function, caused by preoperative halo-pelvic traction (HPT) for the treatment of extremely severe and rigid kyphoscoliosis, with use of 3-dimensional computed tomography (3D-CT) reconstruction and pulmonary function tests (PFTs).

METHODS

Twenty-eight patients with severe and rigid scoliosis (Cobb angle, >100°) underwent preoperative HPT and staged posterior spinal fusion. CT, radiographic assessment, and PFT were performed during pre-traction and post-traction visits. The changes in total lung volume were evaluated with use of 3D-CT reconstruction, and the changes in pulmonary function were evaluated with PFTs at each time point. Differences were analyzed with use of 2-tailed paired Student t tests, and correlations were analyzed with use of Spearman rank tests.

RESULTS

None of the patients had pulmonary complications during traction, and all radiographic spinal measurements improved significantly after HPT. The main Cobb angle was corrected from 143.30° ± 20.85° to 62.97° ± 10.83° between the pre-traction and post-traction evaluations. Additionally, the C7-S1 distance was lengthened from 280.48 ± 39.99 to 421.26 ± 32.08 mm between the pre-traction and post-traction evaluations. Furthermore, 3D lung reconstruction demonstrated a notable increase in total lung volume (TLV) (from 1.30 ± 0.25 to 1.83 ± 0.37 L) and maximum lung height (from 176.96 ± 27.44 to 202.31 ± 32.45 mm) between the pre-traction and post-traction evaluations. Moreover, PFTs showed that total lung capacity (TLC) improved between the pre-traction and post-traction evaluations (from 2.06 ± 0.32 to 2.98 ± 0.82 L) and that the changes in T1-T12 distance and maximum lung height were correlated with changes in TLV (p = 0.0288 and p = 0.0007, respectively).

CONCLUSIONS

The application of HPT is a safe and effective method for improving pulmonary function in patients with extremely severe and rigid scoliosis before fusion surgery. The TLV as measured with CT-based reconstruction was greatly increased after HPT, mainly because of the changes in thoracic height.

LEVEL OF EVIDENCE

Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

A thoracoscopic anterior approach to the spine for adolescent idiopathic scoliosis does not have a detrimental effect on pulmonary function at 2 years compared to posterior-only surgery

PURPOSE

This study aims to examine pulmonary function outcomes in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with an anterior thoracoscopic release compared to those undergoing PSF alone.

METHODS

A retrospective review of patients with AIS over a 9-year period at a single institution compared 2 groups: PSF with video-assisted thoracoscopic surgery (PSF/VATS) and patients undergoing a posterior spinal fusion (PSF) alone. Standard radiographs and Forced Expiratory Volume (FEV1) and Forced Vital Capacity (FVC) were obtained preoperatively and at regular follow up periods up to 2-year post-operatively. Within group and between-group comparisons were performed.

RESULTS

There were 110 patients in the study: 12 in the PSF/VATS cohort and 98 in the PSF only cohort. The PSF/VATS group were younger (12.6 vs. 14.6, p = 0.003) and had larger coronal curves (80.8° vs. 60.7°, p = 0.001), and worse preoperative FVC (64.7% vs. 79.6%, p = 0.018) and FEV1 (62.3% vs. 77.6%, p = 0.003). At 2 years, the percent coronal Cobb correction was greater in the PSF/VATS group (67.9% vs. 48.4%, p < 0.001) with greater improvement in thoracic height (32.8 mm vs. 20.7 mm, p = 0.028). While the 2-year PFTs were the same for FEV1% (75.8% vs. 81.8%, p = 0.368) and FVC% (77.3% vs. 83.7%, p = 0.562), there was greater percent improvement over the 2 years in the PSF/VATS cohort: FEV1% (13.5% vs. 4.2%, p = 0.082) and FVC% (12.7% vs. 4.1%, p = 0.112).

CONCLUSION

AIS patients who have a VATS approach in addition to PSF have greater coronal plane correction and improved pulmonary function compared to PSF alone despite more severe spinal deformity and worse baseline pulmonary function.

Factors affecting postoperative pulmonary function deterioration in adolescent idiopathic scoliosis: A prospective study using 3-dimensional image reconstruction by biplanar stereoradiography

This study aimed both to evaluate rib cage parameters in patients with adolescent idiopathic scoliosis (AIS) by three-dimensional (3D) image reconstruction using biplanar stereoradiography (EOS) (EOS Imaging, Paris, France) and identify factors associated with postoperative pulmonary function deterioration (PFD). A total of 67 patients with Lenke type 1 or 2 AIS (59 females and 8 males; mean age, 14.4 years) undergoing posterior corrective fusion with a rod rotation maneuver based on segmental pedicle screw fixation were recruited. 3D images and pulmonary function test results were analyzed preoperatively and at 2 years postoperatively. The following parameters were measured: maximum thickness, maximum width, thoracic index, rib hump, rib cage volume (RCV), spinal penetration index (SPI), endothoracic hump ratio (EHR), vertebra-sternum angle (VSA), rib-vertebra angle difference, vertebral lateral decentering (VLD), forced vital capacity (FVC), and percent predicted FVC (%FVC). PFD was defined as a postoperative %FVC decline of 5% or greater. Patients were divided into two groups, namely PFD and non-PFD. FVC increased from 2.62 L to 2.73 L, while %FVC decreased from 88.7% to 82.7%. The maximum width diminished postoperatively in the PFD group. Patients in the PFD group exhibited a significantly smaller increase in RCV and VLD as well as a significantly smaller decrease in SPI, EHR, and VSA than those in the non-PFD group. The rib cage parameters quantified on 3D images reconstructed using EOS are useful in identifying factors affecting PFD in patients with AIS.