Several controlled studies have been published recently on the application bone marrow aspirate concentrations to treat osteonecrosis of the femoral head, most of which reported a beneficial effect  of the implantation of bone marrow aspirate concentrations or culture-expanded mesenchymal stem cells. Sen et al.  performed a randomised clinical trial on 51 osteonecrotic hips in 40 patients. Twenty-five hips were treated with core decompression, and 26 hips received autologous bone marrow aspirate concentration instillation into  the core tract after core decompression. After 12 and 24 months, the clinical score and mean hip survival were significantly better in the hips that underwent  additional bone marrow aspirate concentration treatment.