Fig. 1.

a Preoperative anteroposterior radiograph of the left hip in a symptomatic 27-year-old woman with systemic lupus erythematosus (SLE) shows Steinberg stage IIIC lesion in the demineralised bone matrix (DBM) group. b Preoperative frog-leg lateral radiograph of the left hip. c Preoperative MRI of the left hip. d One-year follow-up anteroposterior radiograph of the same hip after free vascularised fibular grafting (FVFG) with OsteoSet®2 DBM. e Two-year follow-up anteroposterior radiograph. f Three-year follow-up anteroposterior radiograph shows stability of the articular cartilage and femoral head