Recapturing the Promise of Total Disc Replacement: Why AxioMed Believes It Can Restore Hope to Those Suffering Back Pain

Here is an in-depth look at the history of total disc replacement and the hope AxioMed's Freedom Disc is bringing to patients: 

By Caitlin Lubinski 

The story of the AxioMed Freedom? Disc is the story about a next-generation technology that has been developed for over a decade with the enormous hope of providing a solution for back pain. But as AxioMed developed and perfected its disc, the events of the total disc replacement (TDR) world swirled around it.  Nothing can be understood apart from its context and that’s why AxioMed’s story is inevitably bound up in the story of the spine industry more broadly.

AxioMed believes its Freedom Disc’s design is a resoundingly solid answer to the questions patients and doctors have about total disc replacement in general. But how did those questions come to be such disquieting figures on the landscape of the spine industry? What happened to the promise of total disc replacement nearly a decade ago? Why did the excitement and intensity surrounding the idea that doctors, researchers and engineers could actually do something new and better in spine treatment dissolve?  To understand why AxioMed believes its disc is about to change the landscape of TDR, it’s important to first understand the context into which it bursts onto the scene.  

In 2004, the DuPuy Charite? Disc was led forth on the medical device market with high expectations as the first total disc replacement to be approved in the U.S. Many believed this would be the ultimate solution for degenerative disc disease (DDD) which is one of the most common causes of back pain –an ailment that plagues over 100 million adults in the U.S.[1]

The standard treatment for DDD was much the same in 2004 as it is today: spinal fusion.  Spinal fusion attempts to lessen the pain of a degenerated disc by fixating two or more vertebrae together to keep them from moving.  Unfortunately, the immobility achieved by fusion eliminates the natural motion with which the spine is intended to function. Fusion can also place extra stress on the surrounding vertebrae, hastening spinal degeneration in those segments as well.[2]

“The ability to replace discs could open up a new era in back treatment.” 

As one might imagine, the promise of a total disc replacement that would treat DDD and also allow the spine to keep its movement was wildly attractive in 2004. The DuPuy marketing machine took advantage of their position as the first FDA-cleared total disc replacement technology in the U.S., and ramped up a considerable marketing effort that gained significant media coverage. [3] One writer in the Wall Street Journal predicted, “The ability to replace discs could open up a new era in back treatment,” but also ominously noted that the Charite’s implant’s long-term durability remained to be proven.[4]

After two years, the Charite Disc had failed rather spectacularly across national headlines. Lawsuits piled up and the tides turned against the Charite.  Dr. McAfee wrote about the theoretical disadvantages of the Charite: “Since artificial hips and knees were introduced in the 1960s, doctors have explored the idea of prosthetic replacements for damaged or degenerated intervertebral discs. The disc is a very complicated joint, so the engineering challenge to partially or fully replace a disc is considerable. Also, because disc injury is a common cause of back pain in younger adults (age 30 to 50), an artificial disc needs to be designed to last for decades.”[5]

New total disc replacements with different designs received FDA approval and entered the arena. But the excitement about TDR’s had wavered –not just because of Charite device failures, but also because it was difficult for doctors and patients to obtain insurance reimbursement for a TDR procedure.

Kari Zimmers, Sr. VP of Research and Development of AxioMed says, “One part of the story of total disc replacement is that no one queued up reimbursement as the first disc, Charite, was being approved for the U.S. market. This heavily impacted sales for Charite and the discs to follow.”

The small army of doctors excited to learn the newest and greatest total disc replacement treatment backed off until they could see long-term evidence of total disc replacement’s legitimacy and better insurance reimbursement. The bubble of total disc replacement was popped, leaving in its place a lingering attitude of skepticism that would become one of TDR’s greatest future opponents.

It’s been over ten years since Charite and other total disc replacements came out, and TDR treatments are starting to show long-term clinical results. From these studies, a few things about total disc replacement have become clear. Several clinical studies for cervical TDR’s have shown positive results. They indicate that TDR’s are at least as effective as fusion, and on certain points, statistically superior to fusion.[6]

Studies are showing that in the long run disc replacement is less expensive than fusion –an important point for those hoping that TDR’s can gain better reimbursement. A study in the June issue of Journal of Neurosurgery: Spine calculated the cost per quality-adjusted life year (the estimated cost of money associated with a medical intervention) for cervical disc replacement was $3,042, versus $8,760 for anterior cervical discectomy and fusion (ACDF)[7].  Another study in the peer-reviewed JAMA Surgery, showed that a two-level Mobi-C? Cervical Disc procedure was more cost-effective than performing a two-level ACDF.[8] Industry insiders are hopeful these results will underscore the value of TDR’s.

Lamenting the lingering skepticism about TDR’s in the face of sound clinical proof, Neel Anand, MD, Clinical Professor of Surgery and Director of Spine Trauma at Cedars-Sinai Spine Center in Los Angeles tells Becker’s Spine Review, “There has not been a single product in the history of orthopedics that has been studied as much as disc replacement or has more scientific data, cost analysis, radiographic outcomes and is still questioned by some in healthcare.“[9]

Although the long-term studies about total disc replacement are encouraging, existing designs have not yet been perfected. One of the major reasons total disc replacement suffered a setback is because early discs were designed as ball and socket joints, similar to the devices used for hip and knee replacements. These designs didn’t provide the right amount of motion and flexibility because the human disc is not a ball and socket joint, but is compressible and made of over 75% water.  

This is where the strength of AxioMed’s disc design shines. The AxioMed Freedom Disc is a single-piece technology made of proprietary polymer that is permanently bonded between two titanium plates.  The polymer has viscoelastic qualities, meaning that it possesses the flexibility and stiffness similar to a normal human disc. AxioMed has an exclusive license on the polymer.  The Freedom Disc has been shown to respond to loading the way a human spine does and tests show it can stand the wear of decades of use.[10] Ultimately, the disc restores the stability, cushioning and three dimensional movement of a healthy, human disc.

For Kingsley R. Chin, the CEO of KICVentures and AxioMed, and a practicing orthopedic spine surgeon the history of AxioMed is an important link. KICVentures acquired AxioMed in 2014. The AxioMed Corporation was started in 2001 by a number of key surgeons, thinkers and engineers who used to work with Art Steffee on the AcroFlex Disc.  Art Steffee was one of the most prominent spine surgeons, entrepreneurs and innovators in the ‘80’s and ‘90’s.[11] AxioMed was a continuation of his work on TDR’s with the intent of solving the problems posed by the AcroFlex disc.

“The Acroflex Disc was one of the first viscoelastic discs, and that’s a true disc replacement,” says Dr. Chin. “If you look at the disc replacements on the market today, these are not real disc replacements. These are really multi-piece devices that move. They are ball and socket joints. The normal human disc is not a joint –it doesn’t move around –rather it acts as a shock absorber, compressing in multiple planes. The AxioMed technology that was developed since 2001 is now a true disc replacement, and it’s exciting to have a technology like this in spine.  In orthopedics we have knee, hip and shoulder replacements, and these are real joints and those technologies change lives and improve the quality of life. In spine, we did not have that before the AxioMed Freedom Disc. We had technologies that fuse the spine –screws and rods and bone graft that limit motion. Now with the AxioMed viscoelastic disc, we have a true opportunity to replace someone’s diseased disc and preserve motion. No more fusion and no excessive motion from ball and socket joints that may over time loosen or shed debris and create all kinds of problems.”

“It’s very important to us that this technology works to the highest standard,” says Dr. Chin.

Over the past 14 years, over $80 million has been spent by AxioMed to develop the Freedom Disc technology. Much of that money went toward making sure that the materials and amount of shock absorption were right and that the material was biocompatible. “It’s very important to us that this technology works to the highest standard,” says Dr. Chin. “We’ve done testing on this disc to show that if it is in the body for decades, it still functions as if you just put it in.”[12]

European studies published in peer-reviewed medical journals about the AxioMed Disc are backing up the talk with clinical results. In the EU there have been no device failures noted in the clinical literature for either the Freedom Cervical or Lumbar Discs at the time of this publication. In an EU clinical study, after two years, half of the patients with a Freedom Lumbar Disc had less than 10% disability score and reported less than 1/10 on the pain scale.[13] The Freedom Lumbar Disc provides better pain relief than anterior lumbar interbody fusion (ALIF) according to an EU clinical study.[14]  The Freedom? Lumbar Disc also performed better than competitor TDRs and is the first device to restore a normal center of rotation to patients (an important factor in keeping the rest of a patient’s spine aligned after the device is implanted). [15] [16]

Both the lumbar and cervical discs are CE-marked and the lumbar disc has been implanted in patients in Europe since 2005. Dr. Oliver Hausmann, a neurosurgeon based in Switzerland and one of the early adopters of the AxioMed disc, says that the technology has performed well for him. His patients have had no side effects due to the device itself, and he is very happy with the two year results of the disc.  Dr. Hausmann chose the Freedom Disc because he likes the concept of the disc’s viscoelastic nucleus, its range of movement, its easy handling and its mobility on axial compression. When comparing the Freedom Disc to other TDRs, Dr. Hausmann says: “The Axiomed [disc] has a better range of movement than the ball and socket [discs].”

AxioMed is currently finishing its IDE on the lumbar disc and hoping to submit a PMA to the FDA by the fall of 2016. Ultimately, they hope to see the Freedom Lumbar Disc on the U.S. market in 2017. The Freedom Cervical disc completed preliminary clinical trials in Europe. AxioMed is raising capital in the United States to bring the cervical disc to the United States and start the IDE by 2016.

Meanwhile, the market for total disc replacement is strong and growing stronger. In Europe, the spine surgery devices market size is predicted to reach 2.37 billion by 2020, as the popularity of non-fusion devices and minimally invasive techniques grow with Europe’s aging population.[17] The Asia-Pacific spinal implant market is expected to double through 2022, reaching nearly $7 billion.[18]  Others predict that motion preservation treatment will become the fuel for the spine industry, with 23% growth over next 5 years, $1.8 billion and a 45% of market share is here in US.[19]

For any company in the spine industry, these numbers represent exciting potentials for business growth. But for the people behind AxioMed, these numbers also represent countless opportunities to lessen people’s pain and give them a newer, better solution than the one the spine industry has been stuck in for decades.

[1] https://iom.nationalacademies.org/Reports/2011/Relieving-Pain-in-America-A-Blueprint-for-Transforming-Prevention-Care-Education-Research/Report-Brief.aspx

[2] https://www.orthospinenews.com/advocacy-isass-policy-statement-cervical-artificial-disc/

[3]https://www.kellogg.northwestern.edu/biotech/faculty/articles/charite_device.pdf

[4] https://www.wsj.com/articles/SB109933755374461355

[5] https://www.spine-health.com/treatment/artificial-disc-replacement/spinal-disc-replacement-charite-artificial-disc

[6] https://www.orthospinenews.com/advocacy-isass-policy-statement-cervical-artificial-disc/

[7] https://www.beckersspine.com/spine/item/22753-5-key-trends-in-cervical-disc-replacement.html

[8] https://globenewswire.com/news-release/2014/10/29/677598/10105011/en/LDR-Announces-Landmark-Publication-in-JAMA-Surgery-on-Cost-Effectiveness-of-2-Level-Mobi-C-R-Cervical-Disc.html

[9] https://www.beckersspine.com/spine/item/22753-5-key-trends-in-cervical-disc-replacement.html

[10] Benzel EC, Lieberman IH, Ross ER, Linovitz RJ, Kuras J, Zimmers K.  Mechanical Characterization of a Viscoelastic Disc for Lumbar Total Disc Replacement.  Journal of Medical Devices 5 (1), 2011.

[11] https://www.spine-health.com/physicians/when-no-good-deed-went-unpunished-first-decade         

[12] Benzel EC, Lieberman IH, Ross ER, Linovitz RJ, Kuras J, Zimmers K.  Mechanical Characterization of a Viscoelastic Disc for Lumbar Total Disc Replacement.  Journal of Medical Devices 5 (1), 2011.

[13] Rischke B, Ross RS, Jollenbeck BA, Zimmers KB, Defibaugh ND.  Pre-Clinical and Clinical Experience with a Viscoelastic Total Disc Replacement.  SAS Journal 5 (4); pp. 97-107, 2011.

[14] Rischke B, Zimmers K, Smith E.  Viscoelastic Disc Arthroplasty Provides Superior Back and Leg Pain Relief in Patients with Lumbar Disc Degeneration Compared to Anterior Lumbar Interbody Fusion.  International Journal of Spine Surgery 9; July 2015.

[15] Rischke B, Kammermeier V, Runkel M, Zimmers K, Kuras J.  Clinical Outcomes for a Viscoelastic Total Disc Replacement Compared to Other Total Disc Replacements in the SWISSspine Registry.  Presented at the International Society for the Advancement of Spine Surgery (ISASS) Annual Meeting, Barcelona, Spain, March 2012.

[16] Newton Ede M, Ross ERS, Rischke B, Joellenbeck B, Hipp J, Zimmers K. An Association Between the Center of Rotation and Clinical Outcome in Patients Implanted with a Viscoelastic Total Disc Replacement.  Proceedings of the British Orthopaedic Association Congress, 2011.

[17] Ibid.

[18] https://www.beckersspine.com/orthopedic-a-spine-device-a-implant-news/item/22354-spine-device-market-report-5-key-concepts-for-future-growth.html

[19] http://www.beckersspine.com/orthopedic-a-spine-device-a-implant-news/item/28641-cervical-total-disc-replacement-device-market-to-grow-to-1-8b-by-2021-5-points.html