Osteoporosis
Also known as: thin bones, brittle bones
Loss of bone mass and deterioration of bone architecture that makes bones fragile and prone to fracture after minimal trauma.
Overview
Bone is constantly remodelled; after the peak mass reached around 30, resorption slowly outpaces formation, sharply so in women after the menopause. Osteoporosis is silent until a bone breaks: the wrist, spine or hip. Hip fractures in older adults carry a high risk of death and loss of independence, and are largely preventable.
Causes
- Oestrogen loss at the menopause
- Ageing
- Long-term steroid treatment
- Low calcium and vitamin D, malabsorption
- Overactive thyroid or parathyroid, low testosterone
- Immobility
Risk factors
- Female sex, early menopause
- Family history of hip fracture
- Low body weight
- Smoking and alcohol
- Previous fragility fracture
- Rheumatoid arthritis, coeliac disease, anorexia
Symptoms
What a clinician may find
- Loss of height, stooped posture (kyphosis)
- Fragility fracture after a fall from standing height
Complications
- Hip, vertebral and wrist fractures
- Chronic back pain
- Loss of independence
Diagnosis
DXA bone density scan (a T-score of −2.5 or lower), fracture risk calculators (FRAX), spine X-ray for vertebral fractures, and blood tests for vitamin D, calcium, thyroid and other secondary causes.
Treatment
Calcium and vitamin D sufficiency, weight-bearing and balance exercise, fall prevention; bisphosphonates (alendronate) first line, denosumab or teriparatide for severe disease; treat secondary causes.
Prevention
Build peak bone mass with exercise and calcium in youth, keep active, do not smoke, limit alcohol, ensure vitamin D, review medicines that cause falls or bone loss.
When to seek care
Any fracture from a minor fall after 50, sudden back pain in an older person, or loss of more than 4 cm in height should prompt assessment.