Don’t Get A Bone Scan Until You Have Read This….
If you’re a woman in midlife and you’re wondering whether you should have your bone density checked, you might assume the first step is simply to ask your GP for a bone scan…..
However it’s not quite that simple!
There are different assessments and knowing what to ask for can make the process less confusing.
1. Start with your fracture risk — not just your bone density
In the UK, the usual starting point for women after menopause who have risk factors for osteoporosis is a FRAX assessment. FRAX estimates your 10-year probability of having a major osteoporotic fracture and of having a hip fracture. It takes into account things such as your age, previous fractures, family history of hip fracture, smoking, alcohol, certain medications and other risk factors.
Your GP can carry out a FRAX assessment and, depending on the result, it may indicate that you need a DEXA bone scan. If you’re wondering whether you qualify for a scan through the NHS, there is also a simplified version of this that the Royal Osteoporosis Society have on their website which will give you a good idea of what questions the FRAX assessment asks and a starting point with your GP: Check Your Risk
2. If you have a DEXA, what will the results actually tell you?
A DEXA measures bone mineral density (BMD), usually at the lumbar spine and hip. You will see a number called a T-score.
This compares your bone density with that of a healthy young adult.
T-score:
-1 or above: normal range
Between -1 and -2.5: low bone density, osteopenia range
-2.5 or below: osteoporosis range
But here’s the important bit; Your T-score is NOT your fracture risk. You can have a T-score in the osteopenia range and still have a relatively high fracture risk. And your fracture risk isn’t determined by the T-score alone.
Your age, previous fractures, family history, medications and other risk factors all contribute to the bigger picture. This is why a DEXA result should be considered alongside your FRAX assessment and other risk factors.
What about your Z-score? You may also see a Z-score on your report.
This compares your bone density with people of a similar age. For most postmenopausal women, the T-score is the more relevant number when classifying bone density.
3. Ask about TBS
This is something I think more women should know about.
TBS stands for Trabecular Bone Score.
It isn’t another scan.
It’s calculated from the images produced during a lumbar-spine DEXA and provides additional information about the structure of the trabecular, or spongy, bone. Think of it as adding another piece to the picture:
DXA → bone mineral density
TBS → information about trabecular bone structure
TBS can be incorporated into fracture-risk assessment and can provide additional information beyond BMD alone. BUT you won’t automatically get a TBS score with every DEXA. So if you’re having a private DEXA, do ask if they offer TBS.
If you’re having a scan through the NHS, it’s worth asking whether TBS is available at that centre, but don’t be surprised if it isn’t routinely offered.
4. What is VFA?
You may also come across VFA — Vertebral Fracture Assessment.
This uses the DEXA machine to produce an image of your spine and look for vertebral fractures. This matters because vertebral fractures can sometimes happen without an obvious accident or even without you knowing you’ve had one.
A previous vertebral fracture can significantly change how your fracture risk is assessed. VFA isn’t necessary for everyone, but if you have certain risk factors, such as height loss, unexplained chronic back pain it’s worth asking for one.
5. What about REMS?
You may have come across REMS if you’ve been researching bone health. REMS stands for Radiofrequency Echographic Multi-Spectrometry.
It’s an ultrasound-based technology that doesn’t use ionising radiation and can assess bone at the hip and lumbar spine. It can produce BMD measurements similar to a DEXA scan but the interesting bit is it can provide a Fragility Score. This is additional data on bone microarchitecture and quality alongside density.
From everything I’ve researched those that have had a REMs scan seem to be getting different results on their likelihood to fracture. In many cases this can be a positive improvement because it’s looking at bone quality not just density.
This may give you more reassurance on your likelihood to fracture but the jury is still out on how reliable this scan is! Please also remember this is just my anecdotal research and not medical opinion.
I’ve also seen that REMs is less accurate if you are very slim or a larger build.
It’s a developing technology, but at the moment, DEXA remains the established method for measuring bone mineral density, and REMS isn’t routinely offered through the NHS or easy to find privately.
So if you’re paying privately, I’d prioritise getting a properly performed and interpreted DEXA, and asking whether TBS is available, before paying for REMS.
BUT saying all of that its still something I’m considering. Let me know if you have had a REMs scan and your experiences with it.
And don’t forget your previous scans
If you’ve had a DEXA before, don’t just look at your new T-score and compare it with the old one yourself. Have your previous scan available so that the clinician can compare the results properly.
Ask whether the change in your BMD is large enough to be considered a genuine change rather than normal measurement variation.
Summary
The aim of all this ultimately is to understand your fracture risk and what you can actually do about it.
Your bone health is more complicated than one number on a scan and that’s actually a good thing.
It means there are things you can influence i.e. strength training, appropriate impact exercise, nutrition and mobility all have a role to play in keeping your bones and body strong as you get older.
This guide is for education and isn’t a substitute for individual medical advice. Your GP or osteoporosis specialist should interpret your results in the context of your health and individual risk factors.