https://scoliosisjournal.biomedcentral.com/articles/10.1186/s13013-017-0144-9
https://scoliosisjournal.biomedcentral.com/articles/10.1186/s13013-017-0143-x
https://scoliosisjournal.biomedcentral.com/articles/10.1186/s13013-017-0146-7