Magnetic Resonance Imaging (MRI) of the Sacrum and Coccyx Without Contrast
MRI creates detailed images of the lower spine, including the sacrum and tailbone, without using injected contrast dye.
["This MRI examines the sacrum and tailbone for injuries and other structural or tissue abnormalities."]
Key facts at a glance
- LOINC
- 36522-1
- Short code
- MR Sacrum+Coccyx WO contr
- Synonyms
- MR Sacrum+Coccyx WO contr
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- mr
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
Magnetic resonance imaging (MRI) uses a strong magnetic field and radio waves to create detailed pictures of the sacrum at the base of the spine and the coccyx, or tailbone. This version is performed without injected contrast dye.
Why might I need this test?
Your clinician may order this MRI to evaluate tailbone or lower-spine pain, trauma, suspected fractures, stress injuries, or persistent symptoms such as pain when sitting. It can also help identify tissue abnormalities that may not be visible on standard X-rays.
How is the test performed?
You will lie on a table inside an MRI scanner while the machine takes images from several angles. The scan may be noisy and can take 30 to 60 minutes, although the exact time varies. A technologist will guide you and may ask you to remain still.
How do I prepare for the test?
Follow the instructions provided by your imaging center. Remove jewelry, hairpins, hearing aids, and other metal-containing items before entering the scanner area. Tell the care team if you have an implanted medical device, pregnancy possibility, or a history of reactions to MRI contrast, even though contrast is not used in this examination.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormal findings may include a fracture, stress injury, degenerative change, fluid collection, inflammation, or a bone or soft-tissue lesion. The results are interpreted together with your symptoms, physical examination, and other imaging or laboratory tests. A radiologist's report is reviewed by your ordering clinician, who can explain what the findings mean for you.
Short name
Sacrum and Coccyx MRI Without Contrast
Frequently asked questions
Is contrast dye used for this MRI?
Does an MRI of the sacrum and coccyx require radiation?
Can I have this MRI if I am pregnant?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy