Fig. 2

Bilateral osteonecrosis of the knees in a symptomatic 39-year-old woman with SCD. (a - d) Proton density fat-suppressed (a, c – sagittal) and T2-weighted (b, d - axial) sequences demonstrate subchondral abnormalities (arrowheads) located in the medial femoral condyle (weight bearing zones). Subcortical high-intensity inner line (a – c) representing granulation tissue. MRI scans before surgery shows osteonecrotic lesion in Ficat I and II on left and right knees, respectively. Both knees were treated with BMC implantation