In addition to direct cell placement by surgery, one group attempted targeted intra-arterial delivery of bone marrow aspirate concentration in the treatment of osteonecrosis of the femoral head. Sixty-two patients with osteonecrosis of the femoral head were recruited and were treated with bone marrow aspirate concentration perfusion via the medial circumflex femoral artery. After 5 years, 92.31% (72 of 78) of hips achieved a satisfactory clinical results while only 6 hips (7.69%) progressed to clinical failure  and require total hip arthroplasty (Mao et al., 2013). The same group performed a randomised controlled clinical trial of combination treatment of biomechanical support (porous tantalum rod implantation) and targeted intra-arterial infusion of peripheral blood stem cells mobilised by granulocyte-colony stimulating factor in osteonecrosis of the femoral head. At 36 months, 9 of the 41 hips (21.95%) in the control group (porous tantalum  rod implantation only) progressed to clinical failure and underwent total hip arthroplasty, whereas only 3 of the 48 hips (6.25%) in the combination treatment group required total hip arthroplasty (Mao et al.,2015).