Quick, comfortable procedure
The scan takes about 15 minutes and requires no special preparation — no fasting, nothing to change out of.
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REMS vs. DEXA
DEXA scan vs. REMS scan
Has your doctor recommended a DEXA scan? Before you schedule that appointment, it's worth understanding what the two technologies actually measure — and where they differ.
Why bone density testing matters
Bone density testing is essential for detecting early signs of osteoporosis before fractures occur. Osteoporosis develops silently — you cannot feel your bones getting thinner, and for most people the first sign is the fracture itself. Early detection changes outcomes, and quality of life.
Traditional testing methods have been the standard for decades, and they work well for many people. But medical technology has evolved, and there is now a radiation-free option that evaluates both your bone density and your bone quality in a single scan.
The DEXA scan: understanding the traditional approach
The Dual-Energy X-ray Absorptiometry (DEXA) scan has been the standard method for measuring bone mineral density (BMD) for decades. It's effective in many cases — and it has several important limitations worth knowing about.
Limited bone quality assessment
DEXA primarily measures bone density, and provides minimal information about bone microarchitecture and quality — the structural properties that also determine whether a bone breaks.
Radiation exposure
DEXA scans expose patients to ionizing radiation. The CDC's safety guidance is ALARA — as low as reasonably achievable — which matters most for anyone needing repeated monitoring.
Two-dimensional analysis
DEXA provides a 2D projection of a 3D structure, which may miss critical structural information about your bone.
Limited predictive value on its own
DEXA results alone may not always provide sufficient information for accurate fracture risk prediction. Many people with dense bones still fracture, and many with thin bones never do.
Reduced sensitivity
DEXA may not detect subtle early changes in bone composition that precede density loss — the changes you'd most want to catch early.
The REMS scan: the advanced alternative
Radiofrequency Echographic Multi Spectrometry (REMS) represents the next generation in bone health assessment. Unlike DEXA, REMS:
Evaluates bone microarchitecture
Assesses not just density but the internal structure and quality of bone tissue.
100% radiation-free
Uses ultrasound technology instead of X-rays, making it safer for monitoring over time.
Enhanced sensitivity
Can detect more subtle bone changes — ideal for catching early signs of osteoporosis.
Comprehensive assessment
Evaluates more parameters of bone health than DEXA for a more complete picture.
Non-invasive comfort
A quick, painless procedure with no special preparation needed.
Same clinical language
Reports T-score, Z-score, and BMD in the units your physician already reads.
More accurate FRAX score calculation
The Fracture Risk Assessment Tool (FRAX) is used to predict your 10-year probability of fracture. Because REMS reports bone quality alongside density, it gives the calculation more to work with:
- Incorporates bone quality parameters beyond simple density measurements
- Provides more detailed structural information about your bone health
- Identifies specific weaknesses in bone microarchitecture
- Enables more personalized treatment recommendations based on comprehensive data
Superior early detection capabilities
When it comes to catching early signs of osteoporosis, REMS is exceptional at:
- Identifying bone quality changes before measurable density decreases
- Detecting subtle alterations in bone microstructure that indicate future risk
- Providing earlier warning signs of potential bone weakening
- Enabling intervention before significant bone loss occurs
The strongest evidence for REMS's predictive value comes from a five-year study of 1,989 patients, in which the REMS-derived Fragility Score outperformed both the DEXA T-score and the REMS T-score at predicting who would actually fracture. That study — and the rest of the published research — is on our research library page.
What to expect at your REMS scan
Your appointment is designed for comfort, convenience, and clinical value.
Results sent to your provider
Your scan is analyzed and a report prepared for you and your physician. We're glad to send it directly to a referring doctor.
Comprehensive reporting
Receive detailed documentation about your bone health status — BMD, T-score, Z-score, and Fragility Score.
Easy to reach
Free on-site parking and step-free ground-floor access at our Northvale, NJ center, serving patients across NY and NJ.
FAQs about REMS scans at Bostdia
If my doctor ordered a DEXA scan, can I get a REMS scan instead?
Yes. Our team can work with your doctor to ensure they receive the comprehensive information they need from your REMS scan. If you have a referring physician, let us know when you book and we'll send the results directly to their office.
Is a REMS scan covered by insurance?
Please contact our team so we can verify your coverage prior to your appointment. We're glad to check your specific situation before you come in.
How should I prepare for a REMS scan?
Unlike DEXA scans that may require avoiding calcium supplements beforehand, REMS scans require no special preparation. There's no fasting, nothing to change out of, and no need to stop any medications.
How long does a REMS scan take?
The scan takes about 15 minutes, and the entire appointment is typically short and straightforward. There's no waiting room marathon — you can drive yourself there and back.
Is a REMS scan painful?
No. REMS scans are completely painless and non-invasive. A probe is passed over the surface of your skin at your lower back and hip — using ultrasound technology similar to what's used during pregnancy. No needles, no injections, no discomfort.
How soon will I get my results?
We'll let you know the timing when you book. Your report covers your bone mineral density, T-score, Z-score, and Fragility Score — and if you have a referring physician, we're glad to send the results directly to them as well.
Does REMS use radiation?
No. REMS uses ultrasound and radiofrequency signals — there is no ionizing radiation and no X-ray at any point. DEXA, by contrast, uses X-ray radiation. The CDC notes that even small doses of radiation should be avoided if practical, and their guidance for radiation safety is ALARA: as low as reasonably achievable.
Is REMS as accurate as DEXA?
In published studies, yes. A multicenter trial of 1,914 postmenopausal women found REMS achieved sensitivity of 91.7% at the lumbar spine and 91.5% at the femoral neck, with specificity of 92.0% and 91.8% respectively. Diagnostic concordance with DEXA — agreement on whether a patient was healthy, osteopenic, or osteoporotic — was 88.8% at the spine and 88.2% at the hip.
What does REMS measure that DEXA doesn't?
Bone quality. Every REMS scan reports the Fragility Score alongside the bone density T-score. The Fragility Score analyzes the raw ultrasound signal for the textural signature of fragile bone. DEXA rarely assesses bone quality at all — and when it does, it can only assess the spine, while REMS reports it for both the spine and the femoral neck.
Can I have a REMS scan if I'm pregnant or breastfeeding?
Women who are pregnant, breastfeeding, of fertile age, or living with anorexia may need more frequent bone density testing. Because DEXA involves X-ray exposure, it is not recommended in these cases. REMS is a safe and effective option for anyone advised to avoid DEXA scans and radiation.
Why does arthritis affect DEXA accuracy?
Arthritis is one of the most common causes of DEXA inaccuracy. Calcium buildup associated with arthritis can distort a DEXA reading, producing a false result that then informs treatment decisions. REMS filters out those distortions — along with several other sources of error — providing a more accurate clinical picture.
Take control of your bone health
Don't wait until a fracture to address your bone health. A REMS scan takes about 15 minutes and uses no radiation — so it can be repeated for monitoring as often as your physician recommends.
If you've been recommended for a DEXA scan, consider how a REMS scan works or read what osteoporosis is.