This study was conducted at the Daping Hospital in Chongqing and investigated the effect of using the patient's own bone marrow stem cells in repairing osteonecrosis at the top of the thigh bone (head of femur). In the study, participants were enrolled into control and test groups. The control group received an implant made from tantalum to correct the osteonecrosis at the top of the thigh. The test group received the same implant but also their bone marrow stem cells. Fifty participants were enrolled in the study that completed in October 2012. The results of this trial do not appear to have been published.