The BMP family of proteins regulates the expression of an important mechanosensing protein, sclerostin, found exclusively in osteocytes (Poole et al., 2005; Kamiya et al., 2016), whereby mechanical unloading increases sclerostin protein expression to promote bone resorption and cause a loss of bone density (Robling et al., 2008) – a phenotype that closely mimics both osteoporosis and osteonecrosis. This evidence concerns the gene SOST and osteonecrosis.