Quantity
Bone mineral density
How much mineral is in a given area of bone. Reported as a T-score and Z-score, and used to diagnose osteoporosis.
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Understanding Your Results
What is a Bone Fragility Score, and why does it matter?
Your bone density is only half the story. The Fragility Score measures the other half — how strong the bone structure itself appears, not just how much of it there is.
The short answer
A Bone Fragility Score is a measurement of bone quality — the internal structure and texture of the bone — rather than bone quantity, which is what a bone density test reports.
It comes from a REMS scan. Alongside measuring how much mineral is in your bone, the system analyzes the raw ultrasound signal for the signature of fragile bone, using reference data from people who have and have not fractured. In effect, it asks a question a density number alone can't answer: does this bone look like the bone of someone who breaks?
It matters because bone density only explains part of your fracture risk. Plenty of people with dense bones fracture, and plenty with thinner bones never do. If you only ever look at density, you're watching one half of the picture.
In one sentence: your T-score tells you how much bone you have; your Fragility Score gives an indication of how strong that bone appears to be. They are two different measurements, and a complete picture uses both.
Density and quality: two different things
Bone is not a solid block. It has an outer shell and an inner, sponge-like structure called trabecular bone — a lattice of struts and spaces. Two bones can hold the same amount of mineral and still be built very differently inside, one with a dense, well-connected lattice and one with thin, disconnected struts.
A density measurement can't tell those two apart. It adds up how much mineral is present; it doesn't describe how the structure is arranged. The Fragility Score is an attempt to capture that second property — the arrangement — from the ultrasound signal itself.
Quality
Fragility Score
An estimate of the structural quality of the bone, based on how the ultrasound signal interacts with its internal texture.
Why it matters when you're being monitored
Monitoring bone health is not really about any single scan. It is about what changes between scans — and there are three reasons the Fragility Score earns its place in that comparison.
It can flag risk that density misses
Someone can sit comfortably in the osteopenia range on their T-score and still have bone that looks structurally fragile. Adding the Fragility Score gives your physician a second, independent signal rather than a second reading of the same one.
It adds context before a fracture, not after
The clearest warning sign in bone health is a fracture — which is exactly the outcome you want to avoid. A structural measure gives something to look at before that happens, rather than explaining the risk in hindsight.
It gives you something to compare
A single score is a snapshot. Two scans a few years apart — density and fragility together — show whether things are holding steady or shifting. That comparison is often what informs a decision about whether to monitor, treat or wait.
A score is not a diagnosis. The Fragility Score is one measurement among several. Your age, medical history, medications, previous fractures and other risk factors all matter, and interpreting them together is your physician's role.
What the research shows
It has been studied against fracture outcomes
This isn't a theoretical idea. In a five-year study of 1,989 patients, the Fragility Score predicted who would go on to fracture more accurately than either the DEXA T-score or the REMS T-score — and the advantage held at both the spine and the hip, in women and men, after adjusting for age and body mass index.
That is the finding that matters for monitoring: a measure only earns a place in a monitoring plan if it adds information the existing measures don't already have. Here, it did.
The full study and the other published research behind REMS are in our research library, so your physician can read the original papers directly.
You don't have to do anything extra to get it
The Fragility Score is not a separate test, an additional appointment or another cost. It's calculated from the same REMS ultrasound scan that measures your bone density — no radiation, and no extra time in the chair.
- One 15-minute, radiation-free ultrasound scan of your spine and hip.
- Your report includes bone mineral density, T-score, Z-score and Fragility Score at both sites.
- If you have a referring physician, we're glad to send the results directly to their office.
- Bring your report to your next appointment and ask what the numbers mean for your situation.
To see how each number on the report fits together, read how to read your bone density results.
Common questions
What is a Bone Fragility Score?
The Fragility Score is a measure of bone quality rather than bone density. It comes from a REMS scan: the system analyzes the raw ultrasound signal for the textural signature of fragile bone and compares your result with reference data from people who have and have not previously fractured. A higher score indicates a bone texture closer to that of people who have fractured.
How is the Fragility Score different from a T-score?
A T-score compares your bone mineral density to that of a healthy young adult, and it is the number used to diagnose osteoporosis. The Fragility Score looks at a different property: the internal structure and texture of the bone. Density tells you how much bone you have; the Fragility Score estimates how strong that bone is.
Can I have a normal T-score and a high Fragility Score?
Yes, and that combination is exactly why the measure exists. Published research has found that many people with dense bones still fracture, and many with thinner bones never do. A normal T-score alongside an unfavourable Fragility Score is a case where bone quality may be telling a different story from bone quantity.
Do I need to have a DEXA scan to get a Fragility Score?
No. The Fragility Score is calculated from the same REMS ultrasound scan that measures your bone density — it is not a separate appointment or an additional test. One radiation-free scan produces your bone mineral density, T-score, Z-score and Fragility Score at the spine and femoral neck.
Is a Fragility Score result a diagnosis?
No. It is a measurement that your physician weighs alongside your T-score, age, medical history, medications and other risk factors. A score is one input into a clinical decision, not a verdict — bring your report to your physician and ask what it means for your specific situation.
What does one number on its own actually tell me?
Less than a trend does. The most useful thing about the Fragility Score in monitoring is change over time: two scans a few years apart show whether your bone quality appears to be holding steady, improving, or declining. A single reading is a snapshot; the comparison is the signal.
Measure both, not just one
A REMS bone density scan takes about 15 minutes and reports your T-score, Z-score and Fragility Score from a single radiation-free test. Serving patients across New York and New Jersey.
New to the scan itself? See how REMS works or compare it with DEXA.