Collagen Cross-Linked N-Telopeptide (NTx), Urine Test
A collagen cross-linked N-telopeptide, or NTx, urine test measures a marker of bone turnover in a urine sample. Clinicians use this marker to help evaluate the pace at which bone tissue is being remodeled over time.
About this test
Bone is living tissue that is constantly renewed: old bone is broken down while new bone is built, an ongoing process called remodeling. When bone is broken down, small fragments of a structural protein called collagen are released, and NTx is one of those fragments. Measuring it in urine gives a clinician a window into how actively that breakdown side of remodeling is happening. The marker describes a rate of activity rather than the amount or strength of bone itself.
Unlike many lab tests, this one uses a urine sample rather than a blood draw. The sample is collected at a Quest patient service center, and people follow any instructions their ordering clinician provides about timing or preparation, since collection details can matter for markers like this. No needle is involved for the sample itself.
It helps to understand what NTx is and is not. It reflects the turnover process, not a picture of bone density, which is measured a different way entirely. Because turnover markers can move for many reasons, a clinician reads NTx alongside a person's history, any imaging, and other markers rather than treating it as a standalone measure of bone health.
Who commonly orders it
People who look into an NTx urine test are often already discussing bone health with a clinician and want a marker that reflects the pace of remodeling over time. It can be of interest when a clinician is following a situation and wants to see how turnover changes across repeated measurements rather than at a single moment.
Others come to the topic curious about how bone renewal is tracked and how it differs from a density scan. In each case the marker is most meaningful within a clinician-guided plan, because interpretation depends heavily on the reason for testing and on what else a clinician is monitoring.
What this test looks at
The test looks at NTx, a collagen fragment released when bone is broken down as part of normal remodeling. Because that fragment appears in urine, its measurement gives a clinician a sense of how active the breakdown side of the cycle is. The reading reflects a rate of turnover, capturing motion in the system rather than a static snapshot of how much bone exists.
That focus on rate is the key distinction. A density scan answers a different question about bone quantity, while a turnover marker like NTx speaks to how briskly bone is being remodeled, which is why the two are often thought of as complementary rather than interchangeable.
How it is often used
Clinicians commonly use bone-turnover markers to follow change over time. Because a single measurement has limited meaning on its own, NTx is frequently most useful when a clinician compares results across a series, watching for trends within the context of a person's overall care. It is one input a clinician weighs alongside history, imaging, and other markers rather than a decision-maker by itself.
What to expect at your visit
This test uses a urine sample collected at a Quest patient service center, so no blood draw is needed for it. People follow any timing or preparation instructions their ordering clinician provides, since those details can influence turnover markers. Once the laboratory completes its analysis, results are posted to the account, where they can be reviewed and shared with a clinician who can place them in context.
Your results
Results will be emailed securely to you as a PDF.
One-time price · physician order included · no insurance needed
Prefer a fuller panel?
A curated bundle groups this test with the markers clinicians most often review alongside it — often better value than single tests.
Frequently asked questions
What does the NTx urine test measure?+–
It measures N-telopeptide, a collagen fragment released when bone is broken down during normal remodeling. The marker helps a clinician evaluate the pace of bone turnover over time.
Is this a blood test?+–
No. NTx here is measured in a urine sample collected at a Quest patient service center, so no blood draw is involved for this particular test.
Is NTx the same as a bone density scan?+–
No. A density scan looks at how much bone is present, while NTx reflects how actively bone is being remodeled. Clinicians often view the two as complementary rather than interchangeable.
Why is NTx often measured more than once?+–
Turnover markers are frequently most useful as a trend. A clinician may compare results across a series to see how the pace of remodeling changes, rather than relying on a single measurement.
Do I need to prepare?+–
Follow any timing or preparation instructions your ordering clinician provides, since collection details can matter for turnover markers. Individual situations and reasons for testing vary.
Can I get the Collagen Cross-Linked N-Telopeptide , Urine test without a doctor's visit or insurance?+–
Yes. The $289 cash price includes an independent physician's order, so no appointment or referral is needed, and insurance is never involved.