Impact of Supine Radiographs to Assess Curve Flexibility in the Treatment of Adolescent Idiopathic Scoliosis. Issue 8 (October 2022)

• Record Type: Journal Article
• Authors: Ramchandran, Subaraman; Monsour, Ali; Mihas, Alexander; George, Kevin; Errico, Thomas; George, Stephen
• Is Part Of: Global spine journal. Volume 12:Issue 8(2022)
• Page Start: 1731
• Page End: 1735
• Publication Date: 2022-10
• Subjects: adolescent idiopathic scoliosis -- structural -- supine radiographs -- side-bending -- flexibility; Spine -- Diseases -- Periodicals; Spine -- Diseases -- Treatment -- Periodicals; Spine -- Abnormalities -- Periodicals; Spine -- Surgery -- Periodicals; 616.73
• DOI: 10.1177/2192568220988271
• Languages: English
• ISSNs: 2192-5682

Abstract

Study Design: Retrospective cohort study. Objectives: The purpose of the study is to evaluate the role of supine radiographs in determining flexibility of thoracic and thoracolumbar curves. Methods: Ninety operative AIS patients with 2-year follow-up from a single institution were queried and classified into MT structural and TL structural groups. Equations were derived using linear regression to compute cut-off values for MT and TL curves. Thresholds were externally validated in a separate database of 60 AIS patients, and positive and negative predictive values were determined for each curve. Results: MT supine values were highly predictive of MT side-bending values (TL group: 0.63, P < 0.001; MT group: 0.66, P = 0.006). Similarly, TL supine values were highly predictive of TL side-bending values (TL group: 0.56, P = 0.001 MT group: 0.68, P = 0.001). From our derived equations, MT and TL curves were considered structural on supine films if they were ≥ 30° and 35°, respectively. Contingency table analysis of external validity sample showed that supine films were highly predictive of structurality of MT curve (Sensitivity = 0.91, PPV = 0.95, NPV = 0.81) and TL curve (Sensitivity = 0.77, PPV = 0.81, NPV = 0.94). ROC analysis revealed that the area under curve for MT structurality from supine films was 0.931 (SEM: 0.03, CI: 0.86-0.99, P < 0.001) and TL structurality from supine films was 0.922 (SEM: 0.03, CI- 0.84-0.98, P < 0.001). Conclusions: A single preoperative supine radiograph is highly predictive of side-bending radiographs to assess curve flexibility in AIS. A cut-off of ≥ 30° for MT and ≥ 35° for TL curves in supine radiographs can determine curve structurality.