Bone densitometry, also known as bone density measurement, is a radiological examination used to quantitatively determine bone mass in a specific area of the skeleton over a given period, using ionising radiation.
Bone density measurement is currently the most widely accepted diagnostic examination for osteoporosis, a systemic skeletal disease characterised by low bone mass and microarchitectural deterioration of bone tissue, resulting in increased bone fragility and fracture risk – particularly in the hip, spine, and wrist, though other areas may also be affected.
The role of radiology in the study of osteoporosis includes: 1. Early diagnosis 2. Assessment of fracture risk 3. Monitoring therapeutic outcomes. There are various methods for measuring bone density.
According to existing Greek and international guidelines, the diagnosis of osteoporosis relies on bone density measurement using dual-energy X-ray absorptiometry (DXA), which is the most commonly used method and the method of choice:
- Bone densitometry, also known as bone density measurement, utilises a specialised machine, the bone densitometer, and specific software to determine whether an individual is healthy or suffering from osteopenia or osteoporosis. At "Ygeia Florinas - Tomodiagnosi Ltd", one of the most reliable, effective, and popular DXA systems in the world is used: the Lunar Prodigy from the American company GE Healthcare.
- Modern machines perform examinations in minimal time – typically 5-10 minutes – and with extremely low radiation doses – approximately 10% of the dose required for a simple chest X-ray and lower than the daily dose of radiation received unintentionally by individuals from the environment.
- The recommended measurement sites include the lumbar spine and the (less dominant) hip ("central" DXA) – for individuals unable to be measured in the above anatomical positions, overweight individuals, and those with hyperthyroidism, the examination is performed at the peripheral end of the radius-ulna ("peripheral" DXA). The selection of these sites is based on: 1. bones in these areas being more susceptible to osteoporotic fractures. 2. fractures occurring in these areas causing more serious problems, having a longer recovery time, causing significant and persistent pain, and potentially leading to disability.
Bone density measurement using DXA is recommended for individuals who, depending on their age, have at least one of the following risk factors related to their medical history and lifestyle:
Age < 50 years
- Low-trauma fracture
- Hypogonadism
- Early menopause (<45 years)
- Malabsorption syndromes
- Primary hyperparathyroidism
- Medication associated with bone loss and/or fracture risk (steroids, aromatase inhibitors, etc.)
- Other diseases associated with bone loss and/or fracture risk (rheumatoid arthritis, Cushing's syndrome, type I diabetes mellitus, severe chronic obstructive pulmonary disease, etc.)
Age 50-64 years
- Low-trauma fracture after the age of 40 years
- Parental hip fracture
- Vertebral fracture and/or osteopenia seen on X-rays
- Low Body Mass Index (<20) and/or weight loss >10% within one year
- Alcohol abuse and/or active smoking
- Other factors and diseases (as in the age group <50 years)
Age > 65 years
- All individuals, both men and women
- Recommendations:
- Bone density measurement using DXA is indicated for individuals of any age, both sexes, if it is deemed that such measurement will contribute to therapeutic decision- making. Postmenopausal women without an indication for initiating therapy are recommended to undergo DXA measurement every two years to evaluate potential changes in bone density.
- Postmenopausal women under therapy are recommended to undergo DXA measurement every year for efficacy assessment/ evaluation of specific treatment.
Contraindications:
- Pregnancy
- Recent radiographic examinations
with barium
- Presence of bone prosthetic
materials – measurement in an alternative anatomical position is
recommended.
- Severe obesity – peripheral DXA
measurement is recommended.
