Diphosphonates remain among the most common drug treatments for osteoporosis. Recent evidence has implicated diphosphonate therapy, specifically, alendronate, with low-energy fractures of the subtrochanteric region of the femur. The general conclusion is that prolonged suppression of bone remodelling with alendronate may be associated with a new form of insufficiency fracture of the femur.

Three case reports of patients with alendronate related insufficiency are discussed here with their treatment modalities and lessons learnt. One of the three patients had bilateral subtrochanteric stress fracture. A comprehensive review of the literature is presented with the best evidence for investigating, treating and preventing these fractures

Our experience in Launceston has increased awareness amongst the local medical community regarding the long term use of Diphosphnates and the fractures they may cause. Changes to our practice have included: Increased suspicion of patients with hip pain on diphosphonate therapy, imaging the contralateral femur to rule out stress fractures, reassuring GP's and Patients that benefits of Diphosphonate therapy far outweigh the potential risks.

There are many unresolved questions about the prolonged use of diphosphonates, but there is sufficient evidence to show subtrochanteric stress fractures do occur. We, as Orthopaedic Surgeons, must be able to recognize this new entity and educate our medical colleagues appropriately.