60 patients with femoral diaphyseal fractures, scheduled to receive operation with closed interlocked nailing were placed in 1 of 2 operative treatment groups to test the effectiveness of cannulated reamer in the proximal fragment as an intrameduallry joystick, and Shanz screw in the distal fragment as a percutaneous joystick during femoral nailing. Patients in group 1 were given the experimental treatment using the cannulated reamer and Shanz screw, while those in the second group were given a conventional treatment (fluroscopy alone). Results showed that those who were operated with a cannulated reamer in the proximal fragment as an intrameduallry joystick, and Shanz screw in the distal fragment as a percutaneous joystick, had significantly reduced guide wire insertion times and radiation exposure during the procedure.