From June 2007 to June 2011, the authors had surgical treatment for 44 patients with 45 closed femur fracture, aged from 16 to 52 years old with interlocking nailing with targing aiming device of the XinRong Best without C - arm at Hospital 7A. Results: skin healing 100 percent success. Bone healing and rehabilitation: good and very good: 94.7 percent, averaging: 5.3 percent.