The next step, he said, would be to figure out which subset of patients may be at heightened risk for the breaks.
The authors of the study, from the University of Sydney in Australia, reviewed records on 152 femoral fractures in 152 patients between 2003 and 2008. Most of the patients were women, with a mean age of 78.
Seventeen of 20 patients who had one of these unusual fractures were taking bisphosphonates (15 were taking Fosamax for an average of five years and two were taking Actonel for about three years).
Two patients who had not had such fractures were taking Fosamax and one was taking Actonel.
There were also other risk factors associated with the type of fracture, such as steroid treatment for more than six months or having rheumatoid arthritis.
Learn more about osteoporosis medications at the National Osteoporosis Foundation.
SOURCES: Kenneth A. Egol, M.D., chief, orthopaedic trauma service, New York University (NYU) Hospital for Joint Diseases, and professor, orthopaedic surgery, NYU Langone School of Medicine, New York City; Yuen Ting (Cathy) Lau, Pharm.D., assistant professor, pharmacy practice, Texas A&M Health Science Center Irma Lerma Rangel College of Pharmacy, Houston; May 13, 2010, New England Journal of Medicine
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