Advancing 3D idiopathic scoliosis assessment through optical scans and web-based integration - Validation of the ScolioSIM system.

BACKGROUND AND

OBJECTIVE

The ScolioSIM module, a novel addition to the web-based ScolioMedIS system, was developed specifically for comprehensive 3D scoliosis visualization and assessment. It utilizes 3D optical scans of the back surface, 3D coordinates of anatomical landmarks, internal and external spinal alignment data, and a generic spine (GS) 3D model to create patient-specific (PS) 3D spine models and deformity parameters. The aim of this paper is to 1) describe the novel ScolioSIM module for scoliosis assessment and 2) validate the agreement between patient-specific (PS) 3D models and Cobb angles produced by the ScolioSIM in comparison to the gold standard - Cobb angles obtained clinically from biplanar radiographs.

METHODS

To generate PS 3D models and deformity parameters, the process includes scanning the patient's back, manually acquiring 3D coordinates of anatomical landmarks and external spinal alignment on the back surface, and determining spinal midline based on X-ray images registered with the surface. Additionally, the process involves uploading the files to ScolioSIM for further analysis, including interpolation, projection, and calculation of spinal deformity parameters, and aligning the GS 3D model to generate the PS 3D model. The deformity parameters are then transferred to ScolioMedIS for inclusion in diagnostic reports alongside the PS 3D spine model. Thirty participants with idiopathic scoliosis (IS) were included in the study, and biplanar EOS radiographs and optical 3D scans were acquired in an upright standing pose using a positioning frame. The study compares Cobb angles generated by ScolioSIM (SCA) with manual assessments on EOS radiographs (MCA) and those computed by sterEOS software (ECA).

RESULTS

A total of 80 curves were measured using ScolioSIM. The mean MCA, ECA, and SCA were 22.8 ± 13.0°, 27.9 ± 13.0°, and 24.9 ± 14.3°, respectively. Results showed excellent correlations between SCA and MCA for the thoracic (r = 0.96, 95 % CI: 0.93 to 0.98), lumbar (r = 0.93, 95 % CI: 0.85 to 0.97), and combined thoracic-lumbar regions (r = 0.93, 95 % CI: 0.90 to 0.96).

CONCLUSIONS

This study introduces ScolioSIM, a web-based module with an optical scan system for 3D assessment of IS, demonstrating a high correlation of Cobb angle measurements with those from the clinical gold standard. Additionally, ScolioMedIS could facilitate multi-center data collection and collaborative decision-making in the management of adolescents with IS. The key advantage of the ScolioSIM module is its ability to compare examinations across different visits longitudinally. ScolioSIM thus holds the potential for monitoring progression and evaluating treatment outcomes in adolescents with IS.