How to Diagnose Osteoporosis: Understanding Bone Density Tests and WHO Guidelines

Understanding Osteoporosis Diagnosis

Osteoporosis is a silent but serious condition that weakens bones, making them more susceptible to fractures. Early detection is crucial in managing the disease effectively and preventing complications such as broken hips or spinal injuries. According to the World Health Organization (WHO), osteoporosis is diagnosed using specific criteria based on bone mineral density (BMD) measurements.

The Role of Bone Mineral Density (BMD)

Bone density testing, typically performed using dual-energy X-ray absorptiometry (DEXA or DXA scan), measures the amount of calcium and other minerals in a segment of bone. The results are compared to the average peak bone mass of a healthy young adult of the same sex, expressed as a T-score. This standardized comparison allows healthcare providers to assess bone health accurately.

Interpreting the T-Score: WHO Classification

Normal Bone Density: A T-score of -1.0 or higher indicates that bone density is within the normal range for a healthy adult. Individuals in this category generally have strong, resilient bones with a lower risk of fracture.

Low Bone Mass (Osteopenia): When the T-score falls between -1.0 and -2.5, it signifies reduced bone density, also known as osteopenia. While not classified as osteoporosis, this stage serves as a warning sign. Lifestyle changes, proper nutrition, and sometimes medical intervention can help prevent progression.

Osteoporosis: A T-score of -2.5 or lower confirms an osteoporosis diagnosis. At this stage, bones are significantly weaker and more prone to fractures, even from minor falls or everyday activities.

Severe Osteoporosis: When Fractures Occur

If a person with a T-score below -2.5 has also experienced one or more fragility fractures—such as those resulting from a fall from standing height or less—it is classified as severe or established osteoporosis. These fractures commonly occur in the spine, hip, or wrist and are a key indicator of advanced bone deterioration.

Why Early Screening Matters

Because osteoporosis often progresses without symptoms until a fracture happens, routine screening is especially important for at-risk groups, including postmenopausal women, older adults, and individuals with a family history of the disease. Early diagnosis enables timely treatment through medications, weight-bearing exercise, adequate calcium and vitamin D intake, and fall prevention strategies.

By understanding the diagnostic criteria and taking proactive steps, individuals can protect their bone health and maintain independence as they age.