Flexion-extension X-rays can be helpful, but they are still static snapshots taken at limited positions. If neck pain, headaches, dizziness, shoulder-blade burning, or arm tingling persist even after “normal” flexion-extension films, the issue may still be motion-based. Digital Motion X-Ray (DMX) evaluates cervical movement in real time and can help identify translation, angulation, asymmetry, hinge behavior, sequencing problems, or instability patterns that static imaging may not fully capture.
- Flexion-extension X-rays show end-range positions, not the full motion sequence.
- Symptoms that happen during movement may require motion-based evaluation.
- DMX can help evaluate real-time cervical translation, angulation, asymmetry, and instability patterns.
Last updated: April 14, 2026
Reviewed by: DMX Miami clinical team
Many patients are told their flexion-extension X-rays are normal, yet they still feel something is wrong. They may continue to have neck pain, headaches, dizziness, clicking, clunking, shoulder-blade burning, arm tingling, or a heavy-head feeling during daily activities.
At DMX Miami, we see this pattern in patients from Miami, Fort Lauderdale, Miami-Dade County, Broward County, and the Florida Keys, along with patients who travel from the USA, Colombia, Chile, Argentina, Mexico, and the Caribbean for a more detailed motion-based evaluation.
Patients often say:
- “My flexion-extension X-rays were normal, but my neck still feels unstable.”
- “I only hurt when I move, not when I sit still.”
- “My MRI was mild, but turning my head causes symptoms.”
- “I feel a clunk that no one can explain.”
- “My symptoms come back after treatment.”
- “I know something moves wrong, but the imaging keeps saying normal.”
This is where the difference between static motion snapshots and real-time motion imaging becomes important.
What flexion-extension X-rays show
Flexion-extension X-rays are still images usually taken with the neck bent forward and backward. They can help evaluate alignment and movement between certain positions.
They may be useful for identifying larger instability findings or alignment changes. But they do not show the full motion pathway.
They are snapshots.
They do not show how the neck moves between those positions.
Why symptoms may still be missed
Many cervical instability symptoms happen during the motion itself, not only at the end position.
A patient may have symptoms during:
- the first part of movement
- mid-range movement
- returning from flexion
- turning left or right
- combining rotation with extension
- looking down while seated
- driving
- checking blind spots
- looking up
- sudden head movement
A still X-ray may not capture the exact moment when abnormal motion occurs.
The sequencing problem
The cervical spine should share motion smoothly across multiple levels. If one segment moves too early, too much, or in an irregular pattern, symptoms may occur.
This can create:
- clicking
- clunking
- catching
- sudden pain
- dizziness
- headache
- shoulder-blade burning
- protective muscle guarding
Flexion-extension X-rays may show the beginning and ending positions while missing abnormal sequencing during the motion.
Why DMX is different
Digital Motion X-Ray (DMX) uses fluoroscopic video X-ray to evaluate spinal movement in real time. Instead of only looking at static images, DMX allows providers to observe how segments move through guided motion.
DMX may help evaluate:
- Translation: abnormal sliding between vertebrae
- Angulation: abnormal tilting between vertebrae
- Asymmetry: left-right motion differences
- Hinge behavior: one segment moving too much
- Sequencing: whether motion is smooth or irregular
- Instability patterns: abnormal motion that may appear dynamically
DMX does not replace MRI, CT, standard X-rays, neurological evaluation, or orthopedic evaluation. It complements them when symptoms are motion-triggered.
When DMX may be helpful after normal flexion-extension X-rays
DMX may be considered when symptoms persist and are clearly tied to motion, such as:
- dizziness with head turning
- headaches with looking down or up
- arm tingling with certain neck positions
- clicking with symptoms
- heavy-head fatigue late in the day
- pain that returns after temporary relief
- symptoms after whiplash or falls
- normal MRI or X-rays but ongoing functional limitation
The more reproducible the motion trigger, the more important motion-based evaluation becomes.
Why this matters after whiplash
Whiplash injuries often involve rapid acceleration, deceleration, ligament strain, muscle guarding, and altered movement control. A patient may look normal while still, but abnormal motion may appear during guided movement.
This is why patients can feel frustrated after being told “everything looks fine” when their symptoms clearly happen during real life.
How DMX findings can change care
If abnormal motion is identified, care may become more specific.
A plan may include:
- cervical stabilization
- upper cervical control
- deep neck flexor endurance
- posture tolerance training
- safer manual therapy selection
- reduced end-range stress during flare periods
- driving and work-position modifications
- coordination with medical, legal, or rehab providers
The goal is not just to find abnormal motion. The goal is to guide safer and more targeted care.
Safety note
Seek urgent medical evaluation if neck symptoms include severe headache, fainting, progressive weakness, severe numbness, vision changes, confusion, loss of coordination, or symptoms after significant trauma.
FAQs
Can flexion-extension X-rays miss cervical instability?
They may miss certain motion patterns because they are static snapshots rather than real-time video of the full movement arc.
How is DMX different from flexion-extension X-rays?
DMX evaluates spinal movement in real time, including translation, angulation, asymmetry, hinge behavior, and sequencing.
Does a normal flexion-extension X-ray mean my neck is stable?
Not always. It may reduce concern for some findings, but motion-triggered symptoms may still require further evaluation.
Does DMX replace MRI?
No. DMX complements MRI, CT, and X-rays when the clinical question is motion and stability.
References
- Cleveland Clinic: Whiplash and neck pain education
- PubMed-indexed literature on cervical videofluoroscopy, whiplash-associated disorders, and dynamic spinal motion assessment
Footer: DMX Miami serves patients in Miami, Fort Lauderdale, Miami-Dade, Broward, the Florida Keys, Florida, the USA, and visitors from Colombia, Chile, Argentina, Mexico, and the Caribbean.
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Call 305-275-7475 orbook your appointment online
Dr. Rodolfo Alfonso, D.C.
Dr. Mark N. Berry, D.C.
Sunset Chiropractic and Wellness
8585 Sunset Dr. STE 102
Miami, Florida 33143