Defective fracture healing in OVX and steroid- induced osteoporosis

The physiological mechanisms of fracture healing have been the topic of active investigation for many years. At the present time ample data exist on the histological, mechanical and biochemical aspects of this process. Most investigators now believe that many of the steps in fracture healing are a recapitulation of what happens in endochondral bone formation. What lies ahead for a better understanding of this process is to uncover the regulatory molecules that control chondrocyte and bone cell proliferation and activity. One area of fracture healing investigation that is just now coming to the forefront is the effect of pharmacologic agents. The recent widespread use of bisphosphonates, estrogen receptor modulators and teriparatide for the treatment of osteoporosis has raised questions about the effect of these agents on fracture healing. Yet another class of pharmacologic agents that requires investigation are COX-1 and COX2 inhibitors. These agents are one of the most commonly used medications for minor musculoskeletal injuries and pain throughout the world, yet we have limited knowledge on how they affect the fracture healing process. The remainder of this discussion will explore fracture healing biology and the role played by prostaglandins and the cyclooxygenase enzymes.