A case of the failure of the ACE Retrograde Trauma (ART) Femoral Nail System (9mm, Titanium alloy) is presented. A 55-year-old female was injured in a traffic accident, and X-ray films showed right femoral supracondylar and shaft fracture. She was treated using an ACE Retrograde Trauma (ART) Femoral Nail System (9mm, Titanium alloy) at our hospital. Partial weight-bearing gait was started 4 weeks after operation, and full weight-bearing 6 weeks. The patient complained of right femoral pain 11 weeks after operation. The nail was broken at the proximal screw hole and femoral shaft fracture was displaced again. The patient was reoperated on using the Osteo IC-Nail System (11mm). The surface of the broken nail was analyzed by Scanning Electron Microscopy (SEM). It was shown that the cause of nail breakage was fatigue destruction. In conclusion, we should use larger nails in this case.
