BACKGROUND:The treatment of infected nonunion is a difficult problem in orthopedic trauma, which needs to completely eliminate foci of osteomyelitis to control infection, repair soft tissue defect and close the wound, repairs bone defects to promote healing and protect limb function as much as possible. Autogenous micromorselized bone can be easily obtained and recombinant human bone morphogenetic protein-2 has variety of sources. Their mixed grafting mode is safe and reliable in repairing of bone defects, which are suitable for repair of infected nonunion. ＜br> OBJECTIVE:To study the operating method and clinical results of repairing infected nonunion using autogenous micromorselized bone grafting mixed with bone morphogenetic protein-2. ＜br> METHODS:Twenty-three cases underwent infected nonunion repair with autogenous micromorselized bone (l ium, long bone metaphyseal cancellous bone) mixed with bone morphogenetic protein-2, including 7 cases of femoral bone defect caused by osteomyelitis after debridement and external fixation and 16 cases of tibial bone infected nonunion. Eleven of 23 cases continued to use the external fixation because of scar contraction or poor conditions of soft tissue, and the other 12 cases switched to use internal fixation. X-tray was taken to evaluate the bone healing at the 1st, 3rd, 6th and 12th months after operation. The function of the affected extremity was assessed by Johner-Wruhs grade. ＜br> RESULTS AND CONCLUSION:Al of the cases were averagely fol owed up for 13.4 months. The bone defects and bone fracture healed in al cases without infection, and the wounds were al sealed. The excellent and good rate according to Johner-Wruhs grade was 95%. These findings indicate that the bone grafting mode of autogenous micromorselized bone mixed with bone morphogenetic protein-2 is characterized as variety of sources, high safety and reliable osteogenic ability in repair of bone defects.