From the Guidelines
X-ray (XR) is not recommended for the diagnosis of osteopenia, as dual-energy X-ray absorptiometry (DXA or DEXA) is the preferred diagnostic method due to its high precision in measuring bone mineral density. The most recent and highest quality study, published in 2022, supports this recommendation 1. According to this study, DXA is the primary imaging modality used to screen for osteoporosis in women over 65 years of age and men over 70 years of age.
Key Points
- DXA scans provide quantitative measurements that allow for accurate diagnosis based on T-scores and Z-scores.
- A T-score between -1.0 and -2.5 indicates osteopenia.
- Standard X-rays can show obvious bone loss but cannot detect osteopenia until approximately 30-40% of bone mass has already been lost.
- DXA scans are particularly recommended for postmenopausal women, men over 70, or those with risk factors such as previous fractures, long-term steroid use, or conditions affecting bone metabolism.
Diagnosis and Treatment
While standard X-rays remain useful for detecting fractures, they should not be relied upon for osteopenia diagnosis. The American College of Radiology Appropriateness Criteria guidelines, as updated in 2022, emphasize the importance of DXA in diagnosing and monitoring osteoporosis and osteopenia 1. Other studies, such as those published in 2017 and 2019, also support the use of DXA over standard X-rays for diagnosing osteopenia 1.
Special Considerations
In certain patient populations, such as those with chronic liver disease or primary sclerosing cholangitis, the risk of osteoporosis and osteopenia may be increased, and DXA scans are recommended for these patients as well 1. Overall, the use of DXA scans for diagnosing osteopenia is supported by the most recent and highest quality evidence, and DXA should be the diagnostic method of choice for osteopenia.
From the Research
Diagnosis of Osteopenia using X-ray
- X-ray is used in the form of Dual-energy X-ray absorptiometry (DXA) for the diagnosis of osteoporosis and osteopenia 2, 3, 4, 5
- DXA is considered the gold standard for diagnosing osteoporosis and assessing fracture risk 2, 3, 5
- DXA measures bone mineral density (BMD) at various sites, including the lumbar spine, femoral neck, and total hip 3
- Lateral spine DXA is more sensitive than anterior-posterior spine DXA for detecting osteopenia, as it measures BMD of the vertebral bodies without contribution from the posterior vertebral elements 4
- Double-energy X-ray absorptiometry (DEXA) can also be used to estimate bone mass in ancient skeletal remains and diagnose osteopenia in these populations 6
Comparison with other Methods
- Quantitative computed tomography (QCT) is a more sensitive method for diagnosing osteoporosis and predicting fractures compared to DXA 2
- QCT measures volumetric BMD, which is a more accurate estimate of bone density than the areal BMD measured by DXA 2
- The combination of DXA and QCT can provide a more comprehensive assessment of bone health and fracture risk 2
Clinical Applications
- BMD testing, including DXA, is used to diagnose osteoporosis or low bone density, predict fracture risk, and monitor changes in bone density over time 5
- The results of BMD testing are used to classify patients as having normal bone density, osteopenia, or osteoporosis, and to guide treatment decisions 5