Researchers found that the patient’s bone tissue was being reabsorbed into the body faster than new bone tissue could be formed at the site where these rare femur fractures occur. According to the authors of the new study, these findings are the first evidence of an association between bone tissue absorption caused by Fosamax use and an increased risk of rare femur fractures.

A previous study in the Journal of Orthopedic Trauma found that Fosamax users were more likely to suffer a type of femur fracture that can occur after falls from a low height. Femur fractures were particularly prevalent in patients who had used Fosamax for a longer than average period of time.