LRP5 and osteonecrosis: Except for the evidence mentioned above, a lot of increasing studies showed that LRP5, a co-receptor of the Wnt pathway, played a prominent role in bone metabolism and remodeling, which was related to the osteoporosis, osteonecrosis of the femoral head, steroid-induced osteonecrosis of the femoral head, osteoporosis-pseudoglioma syndrome and other possible disease (38–43).