Digital Motion X-Ray (DMX) in Murray, Utah

Watch Dr. Dirk Woodmansee demonstrate how Digital Motion X-Ray (DMX) captures cervical spine movement during a series of examinations.

This educational presentation explores flexion, extension, rotation, lateral bending, and upper cervical imaging, illustrating how dynamic imaging can contribute to a comprehensive evaluation of cervical spine biomechanics.

Digital Motion X-Ray is a form of videofluoroscopic imaging.

Traditional radiographs capture individual images. DMX records a sequence of X-ray images while the patient performs controlled movements, allowing vertebral relationships to be evaluated through portions of motion.

That distinction is important:

A static X-ray shows spinal structure at a captured position. DMX allows us to evaluate how vertebrae move in relation to one another during controlled movement.

Published research has investigated cervical videofluoroscopy as a method of analyzing intervertebral motion, including its use in patients following whiplash trauma.

Spinal Instability Evaluation

The spine is designed to move.

The clinical question isn't simply whether movement occurs. It is whether the movement between vertebral segments is consistent with expected biomechanics or whether a motion pattern warrants further clinical consideration.

When clinically appropriate, DMX may provide additional information about:

• intersegmental translation during controlled movement
• angular relationships between vertebral segments
• cervical movement through flexion and extension
• vertebral relationships during lateral bending
• upper-cervical motion when specialized views are indicated

An abnormal motion finding does not automatically establish the cause of a patient's symptoms.

The images must be interpreted alongside the patient's history, mechanism of injury, examination, neurological findings, spinal structure and other appropriate imaging.

A DMX examination involves more than simply watching the spine move on a screen.

The recorded study can be reviewed to evaluate how vertebrae move in relation to one another through controlled portions of cervical motion.

Depending on the clinical question and views obtained, Dr. Woodmansee may evaluate intersegmental translation, angular motion and upper-cervical vertebral relationships during movement.

Evaluating Upper-Cervical Motion

When upper-cervical instability is a clinical concern, specialized views may be used to evaluate the relationship between the upper cervical vertebrae during controlled movement.

Published research involving DMX/videofluoroscopy has used AP open-mouth lateral-bending views to evaluate lateral displacement of C1 relative to C2 in patients with upper-cervical instability. The 2023 Katz, Katz and Freeman case series used this type of dynamic assessment as part of the radiographic evaluation of its patients.

These measurements do not stand alone as a diagnosis.

They are interpreted in the context of the patient's history, examination, structural findings and other appropriate imaging.

Upper Cervical Instability

This is one of the most important things to understand about motion imaging.

DMX allows us to observe and analyze vertebral motion.

Ligaments are among the structures that contribute to spinal stability. Therefore, abnormal vertebral motion may be clinically relevant when ligamentous injury or instability is being considered.

However, DMX does not directly visualize microscopic ligament fibers tearing, and an abnormal motion finding does not by itself identify exactly which individual ligament has been injured.

The Freeman/Katz videofluoroscopy research makes this distinction explicitly: the ligaments themselves are not visualized on videofluoroscopy; instead, abnormal intervertebral motion can provide information relevant to the functional integrity of the ligamentous structures.

Likewise, a DMX study by itself does not establish:

• exactly when an abnormality developed
• that a particular accident caused the finding
• that an imaging finding is the sole cause of pain, headaches or dizziness
• that a patient has a particular degree of permanent impairment

Those questions require the broader clinical—and when appropriate, medical or legal—context.

Patients sometimes ask:

"If I've already had an MRI or X-ray, why would we look at another type of imaging?"

Because these studies provide different information.

Static X-Ray

Conventional radiographs can provide information about spinal structure, alignment, degeneration and bony relationships in the position in which the image was obtained.

MRI

MRI can provide important information about discs, nerve roots, the spinal cord and many other soft-tissue structures.

CT

CT provides detailed cross-sectional imaging and can be particularly important for evaluating bony anatomy, fractures and other conditions.

Digital Motion X-Ray

DMX provides something different: the ability to observe vertebral relationships during controlled movement.

One imaging method does not universally replace another.

The appropriate study depends upon the patient's history, examination and the clinical question being investigated.

Auto collisions can expose the cervical spine to rapid acceleration and deceleration forces.

Immediately following significant trauma, the priority may be evaluating for fractures, neurological injury or other conditions requiring urgent medical care. Depending on the circumstances, radiographs, CT, MRI or specialist evaluation may be appropriate.

Some patients continue to experience symptoms after the initial evaluation, or develop clinical findings that raise questions about spinal motion or stability.

In selected patients, DMX may then be considered as one part of a broader spinal instability evaluation.

Research by Freeman, Katz and colleagues compared cervical videofluoroscopy findings in 119 patients with chronic post-whiplash pain and 77 asymptomatic controls. Their diagnostic model using two or more abnormal videofluoroscopic findings reported 93% sensitivity and 79% specificity for distinguishing the study groups. The findings are promising, but they should be understood in the context of that study population and methodology rather than interpreted as proof that DMX diagnoses every whiplash injury.

Auto Injuries and Spinal Instability Evaluation

The upper cervical spine has unique anatomy and biomechanics.

When upper cervical instability is suspected, the evaluation may involve history, neurological and clinical examination, structural imaging and—when appropriate— assessment of motion.

The 2023 Katz, Katz and Freeman case series evaluated nine adults with radiographically identified upper-cervical instability and loss of cervical lordosis. Dynamic open-mouth lateral-bending imaging was among the methods used to evaluate C1-C2 relationships. The authors reported improvements in clinical and radiographic findings following a rehabilitation program directed at improving cervical lordosis.

Because this was a nine-patient case series, it should not be interpreted as proof that correcting cervical lordosis will resolve upper-cervical instability in every patient. It does, however, provide clinically relevant published work connecting dynamic upper-cervical assessment with structural cervical rehabilitation.

Upper Cervical Instability

The purpose of a DMX study isn't simply to find movement.

Spines are supposed to move.

The important question is whether a motion finding is meaningful in the context of that particular patient.

Dr. Woodmansee considers motion findings alongside the patient's history, previous trauma, symptoms, neurological examination, spinal structure and other available imaging.

Depending on the complete evaluation, the next step may involve:

• corrective chiropractic care
• Chiropractic BioPhysics® rehabilitation
• stabilization exercises
• additional imaging
• medical evaluation
• specialist referral

A normal or inconclusive DMX study is also meaningful information.

The purpose of testing is not to guarantee that an abnormality will be found. It is to help answer a specific clinical question.

DMX and Chiropractic BioPhysics serve different roles.

DMX is an imaging modality that may be used to evaluate vertebral relationships during movement.

CBP is a structural rehabilitation approach that uses objective measurements of posture and spinal alignment to help develop individualized corrective strategies.

When corrective care is appropriate, treatment may include adjustments, exercises and spinal traction directed toward measured structural findings.

Published CBP research has documented measurable changes in cervical alignment with specific rehabilitation protocols. Structural change, however, should not be interpreted as a guaranteed treatment outcome or a promise of permanent correction.

For selected patients, motion findings, structural measurements and clinical examination may therefore contribute different pieces of information to the same overall evaluation.

Corrective Chiropractic Care

DMX uses ionizing radiation, as do conventional radiographs and other fluoroscopic examinations.

Radiation exposure depends on the examination and imaging protocol. As with other medically appropriate X-ray procedures, the objective is to obtain the clinical information needed while minimizing unnecessary exposure.

Whether DMX is appropriate should therefore be determined by the clinical question, the expected value of the information and the individual patient's circumstances.

Technology by itself isn't the evaluation.

Interpretation matters.

Dr. Dirk Woodmansee has been in clinical practice since 1997 and holds Advanced Certification in Chiropractic BioPhysics®.

At Comprehensive Chiropractic Clinic, DMX findings are considered alongside the patient's history, examination, neurological findings, spinal structure and other available imaging.

This approach is particularly useful when evaluating complicated spinal conditions in which the relationship between structure and movement is clinically important.

The objective isn't simply to identify something unusual on an image.

It is to understand what the finding means for the patient and what should happen next.

About Dr. Dirk Woodmansee

1. Freeman MD, Katz EA, Rosa SL, et al. Diagnostic Accuracy of Videofluoroscopy for Symptomatic Cervical Spine Injury Following Whiplash Trauma. International Journal of Environmental Research and Public Health. 2020;17(5):1693.

   Freeman, Katz and colleagues investigated cervical videofluoroscopy in 196 participants—119 with chronic post-whiplash pain and 77 asymptomatic controls. Their findings support continued investigation of abnormal intervertebral motion patterns as potentially useful information in selected post-traumatic patients.

2. Katz EA, Katz SB, Freeman MD. Non-Surgical Management of Upper Cervical Instability via Improved Cervical Lordosis: A Case Series of Adult Patients. Journal of Clinical Medicine. 2023;12(5):1797.

   Katz, Katz and Freeman reported a nine-patient case series involving radiographically identified upper-cervical instability and loss of cervical lordosis. Dynamic upper-cervical imaging was incorporated into the assessment. The small observational design means the findings should be interpreted as preliminary rather than proof of treatment effectiveness.

3. Katz E. Digital Motion X-ray, DMX Identifying Cervical Pathologies with Movement. Journal of Legal Nurse Consulting. 2017;28(3):34–38.