A μCT analysis of the femoral bone stock in osteonecrosis of the femoral head compared to osteoarthrosis

Long-term results of resurfacing in osteonecrosis of the femoral head (ONFH) are lacking and migration of the femoral component, necrosis of the femoral head and fracture of the femoral neck or head have been depicted. The aim of this study was to analyse the bone quality and 3-dimensional microarchitecture of the femoral head and neck in patients with ONFH compared to a group of patients with primary osteoarthritis (OA). mu CT was used to compare the microarchitecture of the femoral head and neck in patients with ONFH (n = 10) and a control group of patients with primary OA (n = 10). No statistical significant differences were found for bone volume and the bone volume fraction, the connectivity density and the structure model index in patients with ONFH and those with OA (P > 0.05). Patients with ONFH and those with OA had a similar trabecular number, thickness and separation (P > 0.05). Based on our findings, we might conclude that hip resurfacing arthroplasty is a possible therapeutic option in the treatment of ONFH of the young and active patient and that an insufficient bone stock in ONFH seems not to be the deciding factor for failure. However, we just focussed on one of probably various factors. Further studies are needed to support these findings.