Novel Surface Topographic Assessment of Lung Volume and Pulmonary Function Tests in Idiopathic Scoliosis: A Preliminary Study

Jessica H Heyer; Jenna L Wisch; Kiran K Nagra; Ankush Thakur; Howard J Hillstrom; Benjamin N Groisser; Colson P Zucker; Matthew E Cunningham; M Timothy Hresko; Ram Haddas; John S Blanco; Mary F Di Maio; Roger F Widmann

doi:10.1097/BPO.0000000000002677

Novel Surface Topographic Assessment of Lung Volume and Pulmonary Function Tests in Idiopathic Scoliosis: A Preliminary Study

J Pediatr Orthop. 2024 Apr 9. doi: 10.1097/BPO.0000000000002677. Online ahead of print.

Affiliations

¹ Department of Pediatric Orthopaedic Surgery, Hospital for Special Surgery.
² Technion, Israel Institute of Technology.
³ Boston Childrens, Department of Pediatric Orthopaedic Surgery.
⁴ Rochester, Department of Orthopaedics, Center for Musculoskeletal Research.

PMID: 38595095
DOI: 10.1097/BPO.0000000000002677

Abstract

Objective: Severe spinal deformity results in restrictive pulmonary disease from thoracic distortions and lung-volume limitations. Though spirometry and body plethysmography are widely accepted tests for pulmonary function tests (PFTs), they are time-consuming and require patient compliance. This study investigates whether surface topographic [surface topography (ST)] measurements of body volume difference (BVD) and torso volume difference between maximum inhale and exhale correlate to values determined on PFTs.

Methods: This study included patients with idiopathic scoliosis and thoracic/thoracolumbar curves ≥40 degrees. Patients received ST scans, clinical examinations, and EOS biplanar radiographs on the same day. PFTs were performed within 3 months of ST/radiographic analysis. Univariate linear regression analysis was used to examine relationships between BVD, PFT values, and mean curves.

Results: Sixteen patients (14.6 ± 2.2 y, 69% females) with idiopathic scoliosis and mean thoracic/thoracolumbar curves of 62 degrees ± 15˚ degrees (45 degrees to 93 degrees) were assessed. BVD displayed statistically high-positive positive correlations with forced vital capacity (R= 0.863, P< 0.0001), forced expiratory volume in 1 second (R= 0.870, P< 0.001), vital capacity (R= 0.802, P< 0.0001), and TLC (R= 0.831, P< 0.0001. Torso volume difference showed similarly high positive correlations to forced vital capacity, forced expiratory volume in 1 second, vital capacity, and TLC, but not residual volume. No correlations emerged between the mean thoracic/thoracolumbar curve and BVD or PFT values.

Conclusion: This study strongly endorses further investigation into ST scanning as an alternative to traditional PFTs for assessing pulmonary volumes. The noncontact and noninvasive nature of ST scanning presents a valuable alternative method for analyzing thoracic volume, particularly beneficial for patients unable to cooperate with standard PFTs.

Level of evidence: Level II-prognostic.