Digital Motion X-Ray (DMX)

Don Chaney pioneered the use of DMX as expert scientific evidence that helps objectively quantify permanent injury. He won the first appellate decision recognizing that DMX is merely a new use of old x-ray technology, and holding that Arkansas juries can hear about DMX testing.

DMX is nothing new. It is a trade name for fluoroscopy, also called video fluoroscopy, which has been around for years. Medical doctors have used it for years to diagnose ligament injuries in the cervical spine. For instance, in the article "Cineradiograms of cervical spine in diagnosis of soft-tissue injuries" JAMA 198(1):143, 1966, published over 40 years ago in the Journal of the American Medical Association, medical doctor researchers concluded:

Buonocare, Hartman, and Nelson examined the cervical spines of 107 patients using cineradiography, including 57 who sustained flexion-extension injuries. They concluded, "The ability to demonstrate localized abnormal motion in the cervical spine allows one to predict soft-tissue injuries and the quality of spinal fusions, spinal stability, and early subluxation of the cervical spine--conditions that may not be identified on static roentgenograms nor at physical examination."

A history of the use of fluoroscopy, and a full bibliography of studies on the technology, of can be found here.


Injury victims must prove their the nature, extent, and permenancy of their injuries in order to receive the compensation they deserve in court. Before digital motion x-ray technology became available, many injury victims settled for lesser amounts than they deserved because it was hard to prove some types of ligament damage with static x-ray, MRI, and CT. Now, with DMX, doctors can actually see abnormal motion and zero in on damaged areas. This objective evidence helps the treating physician identify the area to treated, recommend targeted treatment protocols, and help their patients get the compensation they deserve for their injuries.

History of DMX

The first x-ray was invented in 1895 by Dr. Roentgen, and in 1896    Thomas Edison continued to develop radiography with the invention of    fluoroscopy to show moving x-ray images on a screen. These fluoroscopy    methods evolved and were called cinefluoroscopy, cineradiography, video    fluoroscopy (VF), and now digital or dynamic motion x-ray (DMX),  which  all have the same meaning. As technology progressed the ability  to  record x-ray motion images evolved from movie film to videotape to    digital images, exactly like traditional cameras moving from 35mm film    to digital images. DMX is also similar to MRI and CT digital images  that  can be saved on electronic media and displayed on computer  screens, or  they can be printed on film or paper.

Why is it important to use DMX in spinal ligament cases?

DMX is a medical break-through to objectively demonstrate the  functional loss caused by impaired joints of the spine due to permanent  ligament damage. DMX is the best objective test because normal MRI  testing is primarily concerned with static imaging of intervertebral  discs and nerves, not ligaments, and there are no discs in the upper  cervical spine. DMX is also used as a screening tool when performing  proton density MRI and functional kMRI imaging, which are capable of  showing injuries to some of the individual spinal ligaments.

Many  times injury victims hurt when they move due to spinal instability  caused by traumatic ligament injuries. Most plain film x-rays and  recumbent MRI imaging cannot detect the true cause of the pain or the  full extent of the injuries, which can only be revealed by DMX showing  the abnormal function of the joints in motion. Many of the same  principles followed by radiologists and chiropractic physicians in  reading plain film x-rays are also followed in reading DMX motion  x-rays.

DMX is much improved technology over traditional plain film x-rays by  demonstrating spinal instability due to abnormal joint motion caused  by  ligament damage. At its heart DMX is still a simple x-ray, however,  it  works with a video camera to take 30 individual x-ray frames per  second  to create a motion x-ray that lasts approximately 90 seconds. The video images are made  as the patient’s  head is moved through nine  ranges of motion in a  normal, weight-bearing  posture, thereby  providing an assessment of all  22 major cervical  ligaments.  This  results in about 3,000 individual x-ray images that can be viewed  on a  computer monitor, freeze framed, zoomed in or out, or viewed in  slow  motion. The individual images that best show the damage can be  saved as  static x-ray images by the reviewing physician, and then  analyzed using  x-ray digitization software.

While the ligaments themselves are not  shown on the x-ray  images, the effect of injured ligaments can be  ascertained by abnormal  movement of the spinal vertebral bodies in  relation to each other. An  analogy is to watch leaves blowing in a  tree, where we cannot see the  wind, but we can see the effect of the  wind. Likewise, even though we  cannot see the cervical ligaments, we  can see the results of ligamentous  injuries by abnormal movement of the  vertebral bodies, which is easily  observed by anyone trained in  musculoskeletal radiology using standard  radiology practices.

Who has approved the use of DMX?

The use of DMX was approved for patients with spinal and peripheral  joint disorders by the U. S. Food and Drug Administration in 1994, the  Arkansas Department of Health and Human Services in 2003, the National  Guideline Clearing House (a governmental agency that works with the  American Medical Association and the health insurance industry), the  American Chiropractic Association Council on Diagnostic Imaging  Physicians, the Arkansas Board of Chiropractic Examiners, the Arkansas  Chiropractic Society; and its use endorse by Pain Management, A  Practical Guide For Clinicians by the American Academy of Pain  Management, Occupational Medicine Practice Guidelines by the American  College of Occupational and Environmental Medicine, and further  supported by a large number of peer reviewed medical articles published  in Spine and other medical journals.

The widespread acceptance of DMX is also shown by being at the top of  the list of five approved imaging methods, ahead of MRI and CT  imaging,  for a Medicare documentation requirement to establish a spinal  subluxation diagnosis for a patient before a chiropractic physician  can  be paid for treatment by Medicare.

Other benefits of DMX

There are other benefits of  DMX in  addition to showing function of the cervical spine through  motion  testing. DMX images have an enhancing effect by showing the  cortical  margins of the bones in black. In other words, in a digital  x-ray of an  egg, the shell of the egg appears black, and the contents  are grey. This  allows the interpreting physician to detect compression  fractures which  are occasionally missed by traditional x-ray. Plain  film x-rays do not  show some fractures as well because the cortical  margins are displayed  as white, and the body of the bone is also shown  as white, thus  detecting abnormalities is harder when looking at a  white on white image  on plain x-ray. Another benefit is that DMX  testing only subjects  the patient to a low dosage of radiation because  it uses a low powered  pediatric type x-ray machine, which is good for  imaging necks,  temporomandibular joints, and extremity joints; but does  not have enough  radiation power to image the low back unless the  patient is a child or  small adult person.