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.