Abstract

No validated systems exist for selecting the upper instrumented vertebra (UIV) for optimal postoperative shoulder balance in Lenke type 2 adolescent idiopathic scoliosis (AIS). This study evaluated a new method for shoulder balance prediction using the modified Shinshu line (MSL) for UIV selection in AIS Lenke type 2 curves. Fifty-five consecutive AIS patients receiving posterior spinal fusion (PSF) for a Lenke type 2 AIS curve were retrospectively analyzed according to several UIV determination models. Shoulder imbalance was judged as absolute radiographic shoulder height ≥ 10 mm at the 2-year observational endpoint. The MSL was the line between the center of the spinous process of C7 and that of the lowest instrumented vertebra. The vertebral body first touched proximally by the MSL was defined as the MSL vertebra (MSLV) and recommended as the UIV. The group with the UIV matching the MSLV had a significantly lower prevalence of shoulder imbalance of 23% (odds ratio 4.08, 95% CI 1.22–13.7, P = 0.02). Setting the MSLV as the UIV in PSF for AIS Lenke type 2 may reduce the prevalence of postoperative shoulder imbalance.

Details

Title
Usefulness of modified S-line for upper instrumented vertebra selection in adolescent idiopathic scoliosis Lenke type 2 curves
Author
Mimura, Tetsuhiko 1 ; Ikegami, Shota 1 ; Banno, Tomohiro 2 ; Seki, Shoji 3 ; Ohba, Tetsuro 4 ; Oba, Hiroki 1 ; Kuraishi, Shugo 1 ; Uehara, Masashi 1 ; Munakata, Ryo 1 ; Takizawa, Takashi 1 ; Hatakenaka, Terue 1 ; Kamanaka, Takayuki 1 ; Miyaoka, Yoshinari 1 ; Kurogochi, Daisuke 1 ; Fukuzawa, Takuma 1 ; Haro, Hirotaka 4 ; Kawaguchi, Yoshiharu 3 ; Matsuyama, Yukihiro 2 ; Koseki, Michihiko 5 ; Takahashi, Jun 1 

 Shinshu University School of Medicine, Department of Orthopaedic Surgery, Matsumoto, Japan (GRID:grid.263518.b) (ISNI:0000 0001 1507 4692) 
 Hamamatsu University School of Medicine, Department of Orthopaedic Surgery, Shizuoka, Japan (GRID:grid.505613.4) (ISNI:0000 0000 8937 6696) 
 University of Toyama, Department of Orthopaedic Surgery, Faculty of Medicine, Toyama, Japan (GRID:grid.267346.2) (ISNI:0000 0001 2171 836X) 
 University of Yamanashi School of Medicine, Department of Orthopaedic Surgery, Yamanashi, Japan (GRID:grid.267500.6) (ISNI:0000 0001 0291 3581) 
 Shinshu University, Faculty of Textile Science and Technology, Nagano, Japan (GRID:grid.263518.b) (ISNI:0000 0001 1507 4692) 
Publication year
2022
Publication date
2022
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2723291052
Copyright
© The Author(s) 2022. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.