Texas Back Institute in Plano was at the forefront of artificial disc replacements, with Scott Blumenthal, MD, performing the first case in the U.S. More than 20 years later, the practice completed its 3,000th lumbar artificial disc replacement in January.
Four spine surgeons — Richard Guyer, MD; Jessica Shellock, MD; Scott Blumenthal, MD, and Jack Zigler, MD — spoke with Becker's to reflect on their progress and share their outlook for their field.
Evolving the artificial disc
Dr. Blumenthal performed the first artificial disc replacement at TBI in 2000. The practice reached its 22nd anniversary of performing artificial disc replacements in March, Dr. Blumenthal said.
Major developments in that time include hardware upgrades and the types of cases that can be done, such as multilevel disc replacements and combinations of fusion and disc replacement, Dr. Blumenthal said.
Dr. Zigler recalled the initial learning curve.
"We learned that doing a disc replacement is not like doing a fusion," he said. "It's much more difficult. It's more intellectual work and more technical work because we need to not only clean out the discs … but we also have to make that level move. It has to be mobile and we have to do it because the disc is really just there to control the motion. The motion really comes with the surgeon's technique in making that level dynamic again, and that was a big part of the learning curve and something that we transmit to younger surgeons now because we have that experience."
Dr. Shellock, who has been in practice for 13 years, said she has seen the procedure evolve immensely, especially with patient selection.
"What's happened over time is that we've gotten better at identifying who's a good candidate and maybe who's not," she said. "We have refined the instruments. The approach has gotten even more minimally invasive. And I had the benefit of learning about this replacement from the people who literally were there at the outset of it."
Insurer battles persist
Although artificial disc replacements have seen success for many patients, some insurers have yet to warm up to the technology.
One insurer Dr. Zigler and his colleagues are concerned about is Aetna. The insurer is facing a 239-person class-action lawsuit related to its coverage lapse for lumbar disc replacement.
"They're on really thin ice," Dr. Zigler said. "It's really indefensible at this point for them to say that it's experimental and investigational when it's been FDA approved since 2004. There have been almost 150,000 to 200,000 or more global implants already. So they're just posturing. Other insurance companies have tried to do the same thing, but they've had class-action lawsuits by patients who are more educated than the insurance company 'experts,' and those companies have all capitulated. They've all settled those cases on the eve of trial."
Dr. Guyer said lawsuits will inevitably push Aetna to come around to artificial disc coverage.
"I think it's only a matter of time before they crumble because they'll get tired of getting sued by patients that are good candidates for disc replacement, that are forced to get fusions, when in reality they can have an operation that's much longer lasting compared to fusion," he said. " We looked at all the lumbar artificial disc replacements that we did since March of 2000, and our revision rate is 1.5 percent."
The future of ADR, spine technology
Texas Back Institute will continue to expand its artificial disc replacement program, and even during the COVID-19 pandemic, there was no significant dip in patient volume, Dr. Blumenthal said.
Dr. Guyer said he predicts advancements in how artificial discs are made.
"In the future, we'll see further refinement of materials," he said. "For example, right now we use an artificial disc that's made of plastic and ceramic that has very low wear characteristics. I think in the lumbar spine we will see that as well."
Along with back applications, Dr. Blumenthal said he expects artificial disc technology to grow for the neck.
"Cervical disc replacement is something that probably has an even higher ceiling than lumbar and is applicable to more patients than the lumbar spine," he said. "That's a huge part of our practice as well. I can't envision, except in rare circumstances, recommending a fusion in the cervical spine for a patient because of the cervical disc replacement market."