SummaryBone Strain Index (BSI) is a new dual-energy x-ray absorptiometry (DXA)-based index. We retrospectively evaluated data from 153 postmenopausal women with a history of type 2 diabetes mellitus (T2DM). Lumbar spine and femoral Bone Strain Index (BSI) were sensitive to skeletal impairment in postmenopausal women suffering from T2DM.PurposeBone Strain Index (BSI) is a new dual-energy X-ray absorptiometry (DXA)-based measurement. We evaluated the performance of BSI in predicting the presence of fragility fractures in type 2 diabetes mellitus (T2DM) postmenopausal women.MethodsWe retrospectively evaluated data from a case–control study of 153 postmenopausal women with a history of at least 5 years of T2DM (age from 40 to 90 years). For each subject, we assessed the personal or familiar history of previous fragility fractures and menopause age, and we collected data about bone mineral density (BMD), BSI, and Trabecular Bone Score (TBS) measurements. Statistical analysis was performed having as outcome the history of fragility fractures.ResultsOut of a total of 153 subjects, n = 22 (14.4%) presented at least one major fragility fracture. A negative correlation was found between lumbar BSI and lumbar BMD (r = − 0.49, p < 0.001) and between total femur BSI and total femur BMD (r = − 0.49, p < 0.001). A negative correlation was found between femoral neck BSI and femoral neck BMD (r = − 0.22, p < 0.001). Most DXA-based variables were individually able to discriminate between fractured and non-fractured subjects (p < 0.05), and lumbar BSI was the index with the most relative difference between the two populations, followed by femoral BSI.ConclusionLumbar spine and femoral BSI are sensitive to skeletal impairment in postmenopausal women suffering from T2DM. The use of BSI in conjunction with BMD and TBS can improve fracture risk assessment.