osteoporosis
Meaning of osteoporosis: Spinal fractures are the most common kind and often pass unnoticed, surfacing later as lost height and a stooped upper back.
Definition of osteoporosis
Osteoporosis is a condition in which bone loses both mineral density and internal structure, so it breaks under forces healthy bone would withstand. Bone is living tissue that is dismantled and rebuilt continuously, and osteoporosis develops when removal outpaces replacement over years. It produces no symptoms until a fracture occurs, most often in the hip, spine or wrist.
Why does bone thin?
Two cell types run a permanent renovation. Osteoclasts dissolve old bone; osteoblasts lay down new. Bone mass peaks in early adulthood and drifts downward afterward, and anything tilting the balance accelerates the loss. Estrogen restrains osteoclasts, so its fall at menopause produces a phase of rapid loss in women. The internal architecture matters as much as the mineral content, since the honeycomb of struts inside a vertebra thins and individual struts snap, and strength falls faster than a density measurement alone suggests.
What increases the risk?
| Factor | How it acts |
|---|---|
| Age and menopause | The two strongest factors; loss accelerates after estrogen falls |
| Long-term corticosteroids | Suppress bone formation directly |
| Smoking and heavy alcohol use | Impair bone formation and raise fracture risk independently |
| Low body weight and immobility | Bone responds to load, so less loading means less bone |
| Certain conditions | Overactive thyroid or parathyroid, coeliac disease, chronic kidney disease, rheumatoid arthritis |
Family history contributes, and poor calcium and vitamin D nutrition over years compounds the rest.
How is it identified before a fracture?
A bone mineral density scan, usually a DXA study of the hip and spine, measures bone density and reports it as a T-score, the number of standard deviations away from the average for a healthy young adult. A T-score of -2.5 or lower defines osteoporosis, and scores between -1 and -2.5 are called osteopenia, meaning reduced but not yet in that range. Density is only part of the picture, so risk calculators combine it with age, previous fracture, steroid use and other factors. A fracture from a fall at standing height, called a fragility fracture, indicates the condition regardless of what a scan shows.
Used in a sentence
A bone density scan confirmed a diagnosis of osteoporosis following the patient's wrist fracture.
Good to know
Osteoporosis often produces no symptoms until a fracture occurs, which is why bone density testing, rather than symptoms alone, is generally used to identify the condition earlier in its course.
Word origin
Where “osteoporosis” comes from
Formed from Greek osteon, meaning bone, and poros, meaning pore or passage, combined with the suffix -osis, indicating a disease condition.