en Rheumatology Rheumatology Original Research Original Research <p dir="ltr" style="text-align: justify;"><strong>Background: </strong>Bisphosphonates (BPs) are used extensively for managing the osteoporosis. There are some controversies on atypical fractures of femur that associated with increase in cortical thickness (CT) and BPs&rsquo; use. In this study, the effects of alendronate consumption were studied on femoral CT as a predictor for atypical fracture.</p> <p dir="ltr" style="text-align: justify;"><strong>&nbsp; Methods</strong>: Forty nine post-menopausal women aged 50-70 years with osteopenia-osteoporosis who were treated with alendronate 70 mg/week for at least one year were compared to 49 controls for CT in subtrochanteric region of femur by hip dual-energy X-ray absorptiometry (DXA) scans and hip X-ray. CT and its ratio were measured at 3.5 and 4.0 cm below the tip of the greater trochanter (GT) and 0.5 cm below lesser trochanter (LT) in DXA and at 9.5 and 10.5 cm of GT and 1 cm of LT in X-ray.</p> <p dir="ltr" style="text-align: justify;"><strong>&nbsp; Results</strong>: In this study, 98 women participated whose mean age and age at menopause were 60 (17&plusmn;5.6) and 49 (40&plusmn;2.7) years, respectively. Duration of BP consumption in alendronate group was 1.76&plusmn;1.38 (1-10) years.&nbsp; No difference was seen in the mean of CT and its ratio between the alendronate and control groups in BMD scan or X-ray. The best correlation between two imaging modalities was in cortical ratio in 3.5 cm of GT in BMD scan and 9.5 cm of GT in X-ray.</p> <p dir="ltr" style="text-align: justify;"><strong>&nbsp; Conclusion</strong>: Alendronate treatment did not appear to increase femoral CT throughout the detection limits of BMD scan or X-ray.&nbsp;</p> Osteoporosis, Femoral cortical thickness, Alendronate, Atypical fracture. 141 145 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-1018&slc_lang=en&sid=1 Maryam Mobini mmobini50@yahoo.com 200319475328460023091 200319475328460023091 Yes Diabetes Research Center, Mazandaran University of Medical Sciences, Sari, Iran. Leyla Dehghan ali3abbaspor1@gmail.com 200319475328460023092 200319475328460023092 No Division of Internal Medicine, Imam Khomeini Hospital, Mazandaran University of Medical Sciences, Sari, Iran. Gholamali Yosefi usefi547@gmail.com 200319475328460023093 200319475328460023093 No Valiasr Hospital, Mazandaran University of Medical Sciences, Ghaemshahr, Iran. Reza Ali Mohammadpour mohammadpour2002@yahoo.com 200319475328460023094 200319475328460023094 No Diabetes Research Center, Mazandaran University of Medical Sciences, Sari, Iran. Rohollah Abdi sian_abdi@yahoo.com 200319475328460023095 200319475328460023095 No Mazandaran University of Medical Sciences, Sari, Iran.