The Fracture Math
Bone loss is invisible; fractures are not. This page does the arithmetic that risk headlines usually skip: the absolute odds for hip, spine, and wrist — the three classic sites, each with its own timing and its own aftermath — and why a single fracture at sixty changes the calculation more than any scan ever will.
What the evidence supports
- Roughly 1 in 2 women over 50 will sustain an osteoporosis-related fracture in her remaining lifetime.
- A vertebral fracture raises the odds of another vertebral fracture about fivefold within the first year (Lindsay et al., JAMA, 2001).
- Most fractures occur in women whose T-scores are above the osteoporosis range — density alone systematically underestimates who breaks.
What remains uncertain
- Individual prediction — precisely who fractures when — remains approximate; risk tools give probabilities, not verdicts.
- How much of the mortality that follows a hip fracture is the fracture itself versus the frailty that preceded it.
- Whether the cascade after a first fracture can be fully interrupted by current treatments, and for whom.
Evidence last reviewed: August 15, 2026. Conclusions may change as new research is published.
the absolute risks
Absolute Risk, Stated Plainly
Relative-risk headlines are cheap to produce and misleading to read: a "doubled risk" of a rare event can still be a small absolute risk. So this page works in absolutes. The lifetime frame first: about half of women over 50 will have an osteoporosis-related fracture — wrist, spine, hip, pelvis, or shoulder — at some point (US Surgeon General, Bone Health and Osteoporosis, 2004). For the hip specifically, the number is roughly one in six, and in the United States hip fractures land on the order of 300,000 older adults in hospital each year. The one-year mortality figure — around one in five — is covered by the parent topic; here the point is simpler. These are common events, not rare catastrophes, and they cluster in predictable places at predictable ages. That predictability is the entire opportunity.
Three Sites, Three Stories
"Osteoporotic fracture" sounds like one disease, but the three classic sites behave like three different ones — different ages, different triggers, different aftermaths. Knowing the pattern matters because each site presents its own moment to act:
| Site | Typical decade | How it usually happens | Aftermath |
|---|---|---|---|
| Wrist (distal forearm) | 50s–60s | Fall onto an outstretched hand — a reflex younger bones survive | Heals in weeks; the classic sentinel: associates with elevated risk of later hip and spine fractures |
| Spine (vertebra) | 60s–70s | Often no fall at all — bending, coughing, or nothing obvious; roughly two-thirds are never diagnosed | Height loss, posture change, back pain in some; the strongest predictor of the next fracture |
| Hip | 70s–80s | A fall, usually to the side, onto the hip | Surgery, hospitalization, and the steepest functional and survival costs |
The Distribution of Damage
The hip gets the headlines, but it is the minority of fractures — roughly one in seven of the more than two million osteoporosis-related fractures occurring in US adults fifty and over in a single year (Burge et al., Journal of Bone and Mineral Research, 2007). The spine leads the count, mostly silently. The economic picture is inverted: the hip, though a small share of fractures, drives the large share of the cost and disability. Both facts deserve attention — the spine because it is the quiet signal we miss, the hip because it is the loud consequence.
Why One Fracture Changes Everything
The single most actionable number in this topic is what happens after a first fracture. In a pooled analysis of four placebo groups from osteoporosis trials — 2,725 postmenopausal women — the presence of a vertebral fracture at the start raised the odds of a new vertebral fracture within the first year fivefold (relative risk 5.1), and among women who did fracture, nearly one in five (19.2%) had another vertebral fracture within the following year (Lindsay et al., JAMA, 2001). This is the "imminent risk" window: the highest danger sits in the one to two years right after a fracture, not spread evenly over decades. And it generalizes — any low-trauma fracture raises the odds of the next one, with excess mortality after a hip fracture persisting for years beyond the event itself (Bliuc et al., JAMA, 2009). The clinical translation is blunt: a fracture at sixty is not a fluke to shrug off. It is the skeleton's loudest risk message, and the strongest single reason to escalate — which is why post-fracture bone assessment and treatment are standard care, regardless of what the T-score says. That density-blindness cuts both ways: in the NORA cohort, 82% of postmenopausal women who fractured within a year had baseline T-scores above the osteoporosis line (Siris et al., Archives of Internal Medicine, 2004). Screening by density alone would have missed most of the people who broke.
The Ten-Year Probability: FRAX Without the Black Box
Because density alone is a poor gatekeeper, the field moved to a hybrid: a calculator that combines density with the risk factors that matter independently — age, sex, body mass index, prior fracture, parental hip fracture, current smoking, glucocorticoid use, rheumatoid arthritis, other causes of secondary osteoporosis, and heavy alcohol use — plus optional femoral-neck density, to output a ten-year probability of major osteoporotic fracture and of hip fracture (Kanis et al., Osteoporosis International, 2008). Ten years is not an arbitrary window: it is roughly the horizon over which treatment trials demonstrate benefit. In US practice, treatment is generally considered when the major-fracture probability reaches about 20% or the hip probability about 3% — thresholds that move with age, since a 75-year-old reaches them far more easily than a 55-year-old with the same T-score. The calculator is freely available online; the DEXA page explains which numbers feed it, and the Drug Tier page explains what happens once the probability crosses the line.
The Fall That Precedes the Fracture
A fragile bone that never meets the floor never breaks — most hip fractures involve a fall, usually to the side, with direct impact on the hip. This is why the other half of the math is mechanical: exercise programs that combine balance and functional strength reduce the rate of falls by roughly a fifth to a quarter in older adults (Sherrington et al., Cochrane Database of Systematic Reviews, 2019). The parent topic owns the falls playbook — home engineering, medication review, vision, and the one-leg stand from the Quarterly Audit — and the site's Stability & Mobility and Hidden Vital Signs topics carry the training detail. For this page, the arithmetic is enough: fracture risk is density multiplied by fall risk, and the second factor is often the cheaper one to move.
⚠️ A fracture is a symptom, not just bad luck
A fracture from a fall at standing height or less — a "fragility" fracture — warrants a medical conversation, not a shrug: bone assessment after such a fracture is standard care, because the imminent-risk window that follows it is real and treatable. This is clinician territory: the evaluation, the risk calculation, and any decision about medication belong in a clinician's office, and none of the numbers on this page are a prescription.
Questions, Answered Briefly
- 💥 I'm 55 with no fractures — should I be worried? No. Absolute risk at 55 is low even with mildly low density. What matters is keeping it that way for the next thirty years — load, protein, and not accumulating the modifiable risks.
- 🦴 I broke my wrist ten years ago — does that still count? It counts as history. Risk tools weigh recent fractures most heavily because imminent risk fades with time, but any adult fracture is part of the record your clinician should see.
- 📏 I've lost height — is that a fracture? Maybe. New height loss of more than about two to four centimeters is a reason to look for silent vertebral fractures — an imaging question for a clinician, not a stretch-and-forget observation.
- 🧮 Can I calculate my own FRAX number? You can — the tool is public — but the inputs (especially prior fractures and secondary causes) benefit from a clinician's check, and the number only matters as part of a decision conversation.
- 🏃 What actually reduces my odds? The stack from the parent topic: resistance training with impact, protein, correcting deficiencies — plus balance work against the fall half of the equation, and medication for the highest-risk subset, per the Drug Tier page.
The Bottom Line
- The absolute odds are substantial — about 1 in 2 women over 50 will fracture, and about 1 in 6 will break a hip.
- Each site has its own timing — wrist in the 50s and 60s, spine in the 60s and 70s (mostly silent), hip in the 70s and 80s.
- A first fracture is the loudest risk signal there is — about a fivefold jump in vertebral fracture risk within a year, in a window that treatment exists to close.
- Density alone misleads in both directions — most fractures occur above the osteoporosis T-score line, which is why ten-year probabilities, not single numbers, should drive decisions.
Related Topics
- US Department of Health and Human Services, "Bone Health and Osteoporosis: A Report of the Surgeon General" (2004)
- Lindsay R et al., "Risk of new vertebral fracture in the year following a fracture," JAMA (2001)
- Burge R et al., "Incidence and economic burden of osteoporosis-related fractures in the United States, 2005–2025," Journal of Bone and Mineral Research (2007)
- Bliuc D et al., "Mortality risk associated with low-trauma osteoporotic fracture and subsequent fracture in men and women," JAMA (2009)
- Siris ES et al., "Bone mineral density thresholds for pharmacological intervention to prevent fractures," Archives of Internal Medicine (2004)
- Kanis JA et al., "FRAX and the assessment of fracture probability in men and women from the UK," Osteoporosis International (2008)
- Sherrington C et al., "Exercise for preventing falls in older people living in the community," Cochrane Database of Systematic Reviews (2019)