Assessment of the plane of maximum curvature for patients with adolescent idiopathic scoliosis via computed tomography

Can Computer-Aided Design and Computer-Aided Manufacturing Integrating with/without Biomechanical Simulation Improve the Effectiveness of Spinal Braces on Adolescent Idiopathic Scoliosis?

The CAD/CAM technology has been increasingly popular in manufacturing spinal braces for patients with adolescent idiopathic scoliosis (AIS) in clinics. However, whether the CAD/CAM-manufactured braces or the CAD/CAM-manufactured braces integrating with biomechanical simulation could improve the in-brace correction angle of spinal braces in AIS patients, compared to the manually manufactured braces, has remained unclear. The purpose of this systematic review and meta-analysis was to compare the in-brace correction angle of (1) computer-aided design and computer-aided manufacturing (CAD/CAM)-manufactured braces or (2) the CAD/CAM-manufactured braces integrating with biomechanical simulation with that of (3) manually manufactured braces. The Web of Science, OVID, EBSCO, PUBMED, and Cochrane Library databases were searched for relevant studies published up to March 2023. Five randomized controlled trials (RCTs) or randomized controlled crossover trials were included for qualitative synthesis, and four of them were included for meta-analysis. The meta-analysis effect sizes of the in-brace correction angle for CAD/CAM versus manual method, and CAD/CAM integrating with biomechanical simulation versus the manual method in the thoracic curve group and the thoracolumbar/lumbar curve group were 0.6° (mean difference [MD], 95% confidence intervals [CI]: -1.06° to 2.25°), 1.12° (MD, 95% CI: -8.43° to 10.67°), and 3.96° (MD, 95% CI: 1.16° to 6.76°), respectively. This review identified that the braces manufactured by CAD/CAM integrating with biomechanical simulation did not show sufficient advantages over the manually manufactured braces, and the CAD/CAM-manufactured braces may not be considered as more worthwhile than the manually manufactured braces, based on the in-brace correction angle. More high-quality clinical studies that strictly follow the Scoliosis Research Society (SRS) guidelines with long-term follow-ups are still needed to draw more solid conclusions and recommendations for clinical practice in the future.

Curve type, flexibility, correction, and rotation are predictors of curve progression in patients with adolescent idiopathic scoliosis undergoing conservative treatment : a systematic review

AIMS

The aim of this study was to review the current evidence surrounding curve type and morphology on curve progression risk in adolescent idiopathic scoliosis (AIS).

METHODS

A comprehensive search was conducted by two independent reviewers on PubMed, Embase, Medline, and Web of Science to obtain all published information on morphological predictors of AIS progression. Search items included 'adolescent idiopathic scoliosis', 'progression', and 'imaging'. The inclusion and exclusion criteria were carefully defined. Risk of bias of studies was assessed with the Quality in Prognostic Studies tool, and level of evidence for each predictor was rated with the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. In all, 6,286 publications were identified with 3,598 being subjected to secondary scrutiny. Ultimately, 26 publications (25 datasets) were included in this review.

RESULTS

For unbraced patients, high and moderate evidence was found for Cobb angle and curve type as predictors, respectively. Initial Cobb angle > 25° and thoracic curves were predictive of curve progression. For braced patients, flexibility < 28% and limited in-brace correction were factors predictive of progression with high and moderate evidence, respectively. Thoracic curves, high apical vertebral rotation, large rib vertebra angle difference, small rib vertebra angle on the convex side, and low pelvic tilt had weak evidence as predictors of curve progression.

CONCLUSION

For curve progression, strong and consistent evidence is found for Cobb angle, curve type, flexibility, and correction rate. Cobb angle > 25° and flexibility < 28% are found to be important thresholds to guide clinical prognostication. Despite the low evidence, apical vertebral rotation, rib morphology, and pelvic tilt may be promising factors. Cite this article: Bone Joint J 2022;104-B(4):424-432.