Steroid-associated osteonecrosis: Epidemiology, pathophysiology, animal model, prevention, and potential treatments (an overview)

Xie, Xin-Hui; Wang, Xin-Luan; Yang, Hui-Lin; Zhao, De-Wei; Qin, Ling

In order to reinforce the surgically-induced bone defect resulting from core decompression sequestrectomy and delay the need for arthroplasty, several types of bone grafts have been used to provide mechanical support for the affected joint in Ficat Stage III or in even earlier stages (Fig. 4) . These include autogenous or allogenous cortical bone grafts of ilium, fibula, or tibia alone, or alternatively, these procedures may be combined with core decompression [1, 3] . A vascularised bone graft was used that showed some superior results as compared with most other procedures designed to preserve the femoral head collapse [69, 70] . The autologous bone graft is used as a good substitute of the necrotic site, but limitations include insufficient supply and variation in the osteogenic potential of the graft material. The harvesting of host bone often results in donor site morbidity. Fresh osteochondral allografting is a reasonable salvage option for ON of the femoral condyles, thus total knee arthroplasty (TKA) was avoided in 27 of the 28 of knees at last follow-up [71] . Tantalum rod implantation is a safe "buy-time" technique, especially when other joint salvage procedures are not an option [72] . Tantalum [13, 14, 79] . Most of the bone marrow was collected from the iliac crest, but it was reported that the bone marrow near the site of ON could also be used [80] . Their surgical procedure was less invasive, but it might not be effective for large ON lesions because of larger marrow spacing created after core decompression sequestrectomy. In addition, the animal studies also showed that bone marrow mononuclear cells were beneficial for vascularisation and bone regeneration in SAON [35, 78] . Transplantation of autologous endothelial progenitor cells was also beneficial for SAON at the femoral head in rabbits [81] .