Understanding Your DEXA Scan Results
Your DEXA scan indicates you have osteoporosis at the femoral neck (T-score of -3), which significantly increases your fracture risk, though your 10-year hip fracture probability of 4.2% is relatively modest and suggests you may benefit from pharmacological treatment depending on your overall clinical picture.
What the T-Score Means
A T-score of -3 at the femoral neck meets the WHO diagnostic criteria for osteoporosis (defined as T-score ≤ -2.5), indicating your bone mineral density is 3 standard deviations below that of a healthy young adult reference population 1.
This T-score is used for diagnosis regardless of your sex, as current guidelines recommend using the young adult Caucasian female normative reference database for calculating T-scores in both women and men 1.
Your diagnosis is based on the lowest T-score at any measured site (lumbar spine, femoral neck, total hip, or radius), and in your case, the femoral neck shows osteoporosis 1.
Understanding Your 10-Year Hip Fracture Risk of 4.2%
This 4.2% represents your probability of sustaining a hip fracture over the next 10 years, likely calculated using the FRAX tool, which incorporates both your bone mineral density and clinical risk factors 2.
To put this in context: A 65-year-old White female with a BMI of 25 and no risk factors has a baseline 10-year hip fracture risk of only 1.3% 2, meaning your risk is approximately 3 times higher than this reference point.
However, FRAX has important limitations including outdated mortality estimates (not updated since 2004), use of 30-40 year old cohort studies, binary assessment of glucocorticoid and alcohol exposure, and failure to account for falls history, frailty, or conditions like diabetes 2.
Clinical Implications
Treatment Considerations
Oral bisphosphonates are first-line pharmacological treatment for osteoporosis and should be strongly considered given your T-score of -3 3.
Treatment decisions should not rely solely on the FRAX score, as FRAX is "an important reference platform rather than a definitive gold standard tool" 1.
Your T-score of -3 alone may warrant treatment, particularly if you have additional risk factors such as advanced age, prior fractures, glucocorticoid use, or other clinical risk factors 3.
Important Caveats
Most fragility fractures actually occur in people without osteoporosis (T-scores > -2.5), which is why fracture risk assessment tools like FRAX were developed to identify at-risk individuals beyond just BMD measurements 2.
If you are from a racial or ethnic minority group, be aware that FRAX may underestimate your fracture risk, as race-specific calculators combined with fixed treatment thresholds may be less likely to identify Asian, Black, and Hispanic persons as high risk compared to White individuals 2.
If you have had a prior low-trauma major osteoporotic fracture (hip, spine, forearm, humerus, pelvis), some societies consider this diagnostic of osteoporosis even with normal BMD, which would further strengthen the case for treatment 1.
Monitoring and Follow-Up
Repeat DEXA scans should be performed at 4-8 year intervals for monitoring, as shorter intervals do not improve fracture prediction accuracy 2.
When monitoring treatment response, use absolute BMD values in g/cm² rather than T-scores, and only consider changes significant if they exceed the least significant change (LSC), typically 2.8% when precision error is 1% 1.
Ensure repeat scans are done on the same machine at the same facility with the same positioning to allow accurate comparison 1.