Received: 26 April 2021
Accepted: 3 June 2021
First Online: 15 November 2021
: IRB approval, University of Michigan, HUM 00094642, amendment 00082368, 9/7/18. Per IRB, informed consent was waived for this study due to nature of retrospective chart review only. Parental consent deemed not applicable.
: Not applicable.
: YL has received a research grant and non-financial support from the Scoliosis Research Society. The remaining authors declare that they have no conflicts of interest.