https://scoliosisjournal.biomedcentral.com/articles/10.1186/s13013-017-0147-6
https://scoliosisjournal.biomedcentral.com/articles/10.1186/s13013-017-0148-5
https://scoliosisjournal.biomedcentral.com/articles/10.1186/s13013-017-0145-8