In October, 2010 the Food and Drug Administration (FDA) released a statement regarding a possible increase in atypical fractures of the thigh (femur) in patients who take osteoporosis medications for extended periods of time. Individuals have usually been on the medication for five or more years before the thigh fracture occurred. The medications involved, known as bisphosphonates, include alendronate, Actonel, Atelvia, Boniva, Fosamax and Reclast.
Bisphosphonates and Femur Fracture in the News
Since the FDA statement was released, the media has been full of reports about these unusual (atypical) fractures of the femur and their possible association with osteoporosis medications. These reports have caused lots of anxiety for individuals who are taking these drugs. Despite all the media attention, in reality, these fractures are quite rare compared to hip, spine and other typical fractures that occur commonly in people with osteoporosis who are not treated.
The Truth About Atypical Femur Fracture
In an analysis involving 200,000 women, those taking a bisphosphonate for more than five years were about twice as likely to experience the femur fracture as women who never took them. But, the fractures were still quite rare, occurring in about one in 1,000 women who took the drugs for five years and two per 1,000 in women taking them for seven years or more.
In comparison, without treatment with these medications, about one out of two women will suffer a fracture related to osteoporosis, and one in five who has such a fracture will die within a year. It is clear that bisphosphonate medications prevent thousands of fractures of the hip, spine, wrist and other bones each year. Weighing the benefits against the risks of any medication is important in the decision about whether to take these medications.
So, why would these medications increase the risk of the atypical femur fracture? Experts think the fractures happen because of the way the drugs work: by slowing the rate of bone remodeling, the normal process by which injured bone heals. As a result, microfractures that occur through normal wear and tear are not repaired. The bone can become brittle and crack under minor stress. It takes many years of suppressing bone remodeling to result in the microfractures, which is why the atypical femur fractures are not seen until after prolonged use of the bisphosphonates. It is also important to point out that many millions of people have taken these medications for 10-15 years and have never had a fracture. Experts think there may be certain individuals whose bone remodeling is suppressed too much on these medications and this puts them at increased risk for the atypical femur fractures. Efforts are underway to try to identify these individuals.
What Should Patients and Their Healthcare Providers Do?
Fortunately, there are warning signs before the atypical femur fractures occur. About 80% of individuals who have experienced these fractures have reported pain in the thigh or groin for weeks or months before the fracture occurred. This is good because it gives you and your healthcare practitioner a warning that you may be susceptible to one of these fractures. An x-ray will show telltale changes in the bone that occurs before the fracture. Another important fact is that these fractures usually heal very well and do not cause any long-term disability.
Still, you should take precautions, including:
- Review your medication at least once a year with your healthcare practitioner. Do not stop the medication without seeking their advice.
- If you have been taking bisphosphonates for five or more years, talk with your healthcare practitioner to see if you should consider a break from the medicine or a switch to a different medication.
- If you notice pain in the thigh or groin area, report it to your healthcare practitioner.
Research is ongoing to try to sort out who is at increased risk for atypical femur fractures, since thousands of people take bisphosphonate for 10-15 years without a problem. For individuals who are at high risk of fracture due to osteoporosis, the rare incidence of atypical femur fracture should not discourage use of these effective drugs. They prevent thousands of hip, spine, wrist and shoulder fractures each year.