24 | Zimmer Natural Nail – Cephalomedullary Asia Nail Surgical TechniqueFreehand Technique for Long NailsInsert the free hand 4.3 mm drill bit (red) into thedistal targeting device. Finger tighten the set screw.Position the C-arm in order to get a lateral view of thedistal femur. Adjust the angle of the C-arm so thatthe hole through the nail appears as a perfect circleon the monitor. Bring the tip of the drill bit to the skinand use the C-arm to center it over the hole that youdesire to place a screw through. Make a stab woundat this point and dissect down to the bone. Place thetip of the drill bit against the bone. Verify that the tipof the drill bit is in the center of the hole. Align thedrill bit with the C-arm beam. Tap the drill bit intothe bone using the mallet.Remove the distal targeting device. Slide the freehand tissue protection sleeve over the drill bit.Attach the drill to the free hand 4.3 mm drill bit andadvance the drill bit through the bone. Verify thatthe drill bit has gone through the hole in the nail.Remove the drill bit. Measure the depth of the holeusing the free hand screw depth gauge. Insert theappropriate length screw using the screwdriver.If using the captured screwdriver, place theappropriate screw on the 3.5 mm hex and tightenthe screw to the captured screwdriver by turningthe knob next to the handle clockwise (Figure 35).Caution: If using the captured screwdriver, donot torque the captured screwdriver beyond thecalibration line next to the handle.Caution: Do not drive the screws into the boneunder power, as damage to the bone, screws andnail could result.Repeat these steps to insert additional distal screws.Figure 35