Why is a Digital Motion X-ray more expensive than a regular x-ray? A Digital Motion X-ray or DMX is an advanced form of imaging, such as MRI's CT scans, Fluoroscopy, etcetera. It is a a low radiation fluro based form of imaging. As with all specialized imaging, the equipment required to produce a DMX is more costly to purchase and maintain than standard x-rays.
I heard a DMX is good for evaluating ligament damage, but x-rays don't show ligaments. Wouldn't an MRI be better to see ligaments? MRIs are superior for seeing soft tissue such as ligaments. The MRI ability to see the various tissues makes it a great resource for determining soft tissue pathology. If a ligament is torn, an MRI has the ability to see just how torn that ligament is. Every type of imaging has their specific benefits and limitations. For this reason, we still use all forms of imaging such as x-rays, ultrasound, and CT in addition to MRI. One specific benefit of a DMX is that it handles the biggest limitations of all other imaging, MOTION. The primary function of ligaments, is to maintain the stability of a joint while the joint moves. Just as a torn ligament could still maintain stability to the joint it supports, an overstretched ligament will not. An overstretched ligament is rarely detectable on an MRI. Unless you see the joint move, you really have to guess if a ligament is doing its job or not. For this reason, MRIs are unreliable for finding instability from overstretched ligaments.
Regular X-rays and MRIs have found joints that have slipped over another joints, Isn't this ligament instability? If it is, why would I need a DMX? It is true that regular x-rays and MRIs have found slippages (such as anterior translations, posterior translations, or lateral translations). These translations could indicate that the ligament that should prevent that movement is damaged. In fact many times, it is safe to assume that the ligament is compromised to some degree. With out seeing that joint in motion, we don't really know if that found translation is actually a partially dislocated joint that is "jammed" into the translated position. Additionally, without seeing it move, we also do not know the degree of instability. A DMX will show exactly when a joint becomes unstable and will show the most degree of instability that occurs. This means we know which ligament is faulty and just how much it is faulty. Another challenge with static imaging is trying to catch the instability. Since it varies as to when joint instability occurs during the range of motion, it is highly likely, the instability will be missed with static images such as x-ray's or MRIs.
It hurts when I move. I found similar imaging to DMX that offers passive motion, wouldn't that be better than a DMX? While its nice to have a comfortable evaluation, the question to consider is this; Do you want to see what your joints are doing when they are supported mechanically by an external mechanism or would you like to see what your joints are doing when you are not supported by any other means other than your own supporting tissues? I am sure there are benefits to a passive range of motion joint assessment, however when it comes to assessing ligament integrity, the best way is to see it in action, without support.
How long is a DMX evaluation? Usually, it is about 1/2 hour. Allow an hour for any possible complications that may occur. Due to pain or various circumstances, Some sections may have to be repeated. Also, we review the captured video with you to assure we have captured the required images as well as to answer any questions you may have.
Will I receive a copy of my DMX and report? Yes, We will automatically send you a copy as well as those you have authorized to receive a copy. Please keep your copy to share with additional providers you may encounter to avoid an additional record retrieval and submitting fee.
I had an IME provider review my DMX. The IME said that the DMX is of no diagnostic benefit and is excessively radiating me. Is this true? Absolutely not true. This statement is either being made for one of two reasons. The IME is not as independent as they are supposed to be, or they are unknowledgeable as to what a DMX is. Most IMEs I have encountered are well meaning. Generally speaking, I find that they were unfamiliar with DMX and assumed it to be the same thing as video fluoroscopy. I have challenged this statement a few times. A DMX is a low radiating flouro based imaging. Basically DMX it is an x-ray video at 30 frames per second. Each frame is just as diagnostically beneficial as regular x-rays. Due to the nature of real time images, It has much more x-ray images than a standard x-ray. The more images, the better chance to find motion related conditions. As for radiation, a full cervical assessment of DMX images ( about 2700 frames) will produce the same amount of radiation as a standard 7 view ( 7 frames) cervical x-ray. Don't let them convince you otherwise. Insurance companies already know this to be true, but they are hoping you and your attorney wont know or challenge them on this. It doesn't matter how credentialed and experienced your IME is, the truth is, DMX is the gold standard to evaluating ligamentous instability! ( see report under the heading, "for the doctor")
If you have questions, not answered here, feel free to reach out to me. If I run into more common questions, I will add them here.
Improved diagnosis with better imaging - That's Arizona Digital Motion X-Ray