A Risk Quantification Reference Table for Progressed Adolescent Idiopathic Scoliosis Surgery: An Exact Case Matched Outcomes Analysis

Gabriel Liu; Jun-Hao Tan; Gerald Fung; Sijian Hui; Leok Lim Lau; Yiong Huak Chan; Hee-Kit Wong

doi:10.1177/21925682221079262

A Risk Quantification Reference Table for Progressed Adolescent Idiopathic Scoliosis Surgery: An Exact Case Matched Outcomes Analysis

Global Spine J. 2023 Oct;13(8):2228-2238. doi: 10.1177/21925682221079262. Epub 2022 Mar 8.

Authors

Gabriel Liu¹, Jun-Hao Tan¹, Gerald Fung², Sijian Hui³, Leok Lim Lau¹, Yiong Huak Chan⁴, Hee-Kit Wong¹

Affiliations

¹ Department of Orthopaedic Surgery, University Spine Centre, Singapore.
² Department of Orthopaedic Surgery, National University Hospital, Singapore, Singapore.
³ Yong loo Lin School of Medicine, National University of Singapore, Singapore.
⁴ Medicine Biostatistics Unit, Yong Loo Lin School of Medicine, Singapore.

Abstract

Study design: Retrospective Exact Matched case-control study.

Objectives: Surgical treatment delay in AIS due to family preferences is common. This study aims to quantify the increase in risks as the Cobb angle increases and provide a Quantifiable Risk Reference Table that can be utilized for counseling.

Methodology: AIS patients were divided into 3 groups: Group A: Cobb angle 50-60°, Group 61-70°, and Group C_Final ≥80°. Each patient in Group C_Final who had curve progression were then traced-back-in-time (TBIT) to review the clinical data at earlier presentations at 50-60° (C₁), and 61-70° (C₂). Patient demographics, radiological, operative, and outcomes data were compared between Group A vs C₁ and Group B vs Group C₂.

Results: A total of 614 AIS surgeries were reviewed. Utilizing the EM technique, a total of 302 AIS patients were recruited. There were 147, 111, 31, and 32 patients matched in Groups A, B, C_1, and C₂, respectively. C_{2 Final} patients had 34% curve pattern change, 23.2% higher incidence of requiring two surgeries, and 17.3% increase in complications. There was a statistically significant increase of 2.4 spinal levels fused, 12% increase in implant density, 35% increase in operative time, 97% increase in intra-operative blood loss, 10% loss of scoliosis correction, 40% longer hospitalization stay, and 36% increase in costs for patients who had curve progression.

Conclusion: This study is the first to use a homogenously matched AIS cohort to provide a Quantifiable Risk Reference Table. The Risk Table provides essential knowledge for treating physicians when counseling AIS patients.

Keywords: AIS; adolescent idiopathic scoliosis; delay; exact-matched; outcome analysis; risk quantification reference table.