Fractures of the femoral shaft treated with interlocking nails will ultimately result in breakage of the nail if the bone does not unite. Further management requires removal of the broken nail which may be a difficult process for the distal segment. If we can identify the symptoms just before the nail breaks, an exchange nailing becomes much easier. We present a patient with fibromatosis who underwent repeated surgery as well as radiotherapy at the age of 16. Six years later, she had a pathological fracture of the upper third of the femur for which an interlocking nail was inserted. The femur did not unite and the nail subsequently broke. Over a period of 12 years, three nails broke and had to be replaced. Two to 3 months before each breakage, the patient experienced the same set of symptoms for each episode. Knowing that her fracture was not going to heal will now alert us to do an exchange nailing before the nail broke again. It is well known that where there is evidence of non-union, pre-emptive treatment is necessary before implant failure.
KEY WORDS: Femur nonunion, interlocking nail, symptoms before breakage of nail.