Jared Ament, MD, is at the forefront of new motion-preserving spine techniques.
Dr. Ament and Amir Vokshoor, MD, debuted a 360-degree spine procedure combining Premia Spine’s Tops and Centinel Spine Prodisc-L implants. He also introduced a combination surgery with the Motus total joint replacement implant and the Tops system at adjacent levels with Todd Lanman, MD.
The milestones mark an advancement in motion-preserving surgery that he said he hopes will improve access to spine care.
Note: This conversation was edited for clarity and length.
Question: Can you tell me more about these procedures and how you got involved with these?
Dr. Jared Ament: It’s more than just the TOPs and disc replacement combo. We’ve started a formal clinical trial with almost 20 patients enrolled over the last year and a half. The idea really stemmed from a lack of options for patients other than fusions. When we were evaluating the artificial facet device we realized that most of the patients who were being excluded from the original FDA trials and after approval were excluded because they had inadequate disc space.
The standard of care has always been when someone has a slipped spine, to lock it in place and stop the slip. You fuse it and make sure that the nerves are open and decompressed and breathing and healthy. It was a four to five decade old technology, and it didn’t make any sense to me. If someone has a bad hip or knee they get a new joint. Who’s fusing knees or hips? The funny thing is that four or five decades ago that was the only option. You fuse the joint. But the standard of care in orthopedics became replacing the joint. Let’s give people a better quality of life. And I couldn’t understand in the spine world, why we were so antiquated. Why were we stuck with this fusion mentality?
So we looked at all these options. Artificial disc replacements have been around for decades. I looked at the TOPS device, and found that these two exclude each other for disease processes. If someone needs an artificial disc replacement, one of the biggest reasons they can’t get it is because their facets are bad.
If someone needs an artificial disc because their disc is bad and they can’t get it because the facets don’t work, we’re out of luck. When the artificial facet came out, you replaced the facets in the back with a beautiful moving segment. But it’s designed to work with a disc. Why should we exclude these patients from a motion preservation option? If it’s just because the disc isn’t viable enough, the two have to work together.
We’re doing all these studies, and we’ve done this in several patients now with varying degrees of spondylolisthesis. We have a paper being published on the first ever grade three spondylolisthesis slip being corrected with this hybrid ADR and TOPS combination. Although it’s still very early in the trial phase, the early data is that it’s stable and robust. It’s not going to cause a worsening slip, it’s not going to break down, and the motion is preserved and more physiologic.
Q: How have the learning curves been in these cases?
JA: Well most people haven’t done many TOPS cases because it’s relatively new. I was fortunate enough to be part of the original FDA trial. The learning curve with TOPS is not awful because the whole procedure was designed to be pedicle-based and very familiar to surgeons. But like anything else in motion preservation, it’s a very interesting learning curve because it’s nuanced. So it’s not a steep learning curve. It’s actually a very slow learning curve because most people can do it decently based on prior training and artificial disc is the same. But what Todd Lanman, MD, myself and some of my mentors have looked at for years are the nuances. How do we make an artificial disc or an artificial facet work that much better than just average? When we start putting them together, the learning curve is similar.
Q: Can these types of surgeries be done with other devices?
JA: We’re limited in the United States just based on what’s available because we can only work with what’s FDA approved. Or if something’s on a particular trial we’re asked to follow within the realms of that trial. We have looked at some data out of Europe that has used different devices for similar concepts, and we’re using that just to inform our decisions and make better judgments and better calls.
