The changing face of orthopaedic trauma: fragility and periprosthetic fractures.

Because fragility fractures and periprosthetic fractures represent an increasingly common source of morbidity for the elderly population, all orthopaedic surgeons should be prepared to care for such injuries in their practice. Fractures in elderly patients appear to heal more slowly because of decreased numbers and responsiveness of osteoprogenitor stem cells, and stable fixation is more difficult to achieve. It is important to review the mechanical and biologic considerations relevant to the treatment of these challenging injuries.