When selecting materials, orthopaedic device manufacturers seek a total solution: optimal mechanical performance, osteoconductive, radiolucent, sterile, neither too weak nor too rigid and—a growing factor in the equation—economical. The inclusion of these indicators and more is a shift for the industry.
Materials used in orthopaedic and spine implants tend to enjoy long, dominant runs. Over time, limitations are exposed and new materials enter the conversation. As orthopaedics has moved at a more advanced pace, new material technologies have been a root for innovation. Orthopaedic manufacturers and their supplier partners are adopting different strategies for how materials are surface treated and manufactured in order to enhance device performance.
BONEZONE chose four companies that recently reached milestones, such as clinical studies, regulatory clearance or product launch, with proprietary technologies. Each was queried about their technology, the future of materials and the challenges that companies face in adopting new materials.
Oxford Performance Materials and nanoMag are material companies that believe they have a clinical solution for the orthopaedic industry, while Proxy Biomedical and Titan Spine focus on enhancing a material’s foundation. All four mentioned the importance of proving cost containment, whether at the point of manufacturing or at patient recovery.
Company: Titan Spine
Product: nanoLOCK™ surface technology
Applications: Company’s own Endoskelteon® interbody fusion titanium implants
Status: 510(k) November 2014
Interviewed: Jim Sevey, Senior Nanotechnology Specialist
How it works: The nanoLOCK™ surface creates an enhanced osteogenic environment to aid in the fusion process. Its topography at micro (10-6 M) and nano (10-9 M) levels, which cannot be seen or felt, interacts with stem cells in a lock-and-key fashion to induce cellular transcription. This biochemical cellular process results in the upregulation of bone growth factors, such as BMP-2, 4 and 7, as well as angiogenic factors necessary for fusion. Therefore, rather than being simply a spacer, the nanoLOCK implant participates in fusion at the cellular level.
The nanoLOCK surface is the first and only nanotechnology cleared by FDA for spinal applications.
Advantages: As shown by Barbara Boyan, Ph.D., in multiple peer-reviewed journal articles in Spine, nanoLOCK technology has a significant competitive advantage because it is designed to harness the body’s natural cellular biochemical processes to induce bone healing. The most common implant material used for interbody fusion implants, PEEK, has actually been shown to produce an inflammatory response that inhibits fusion and leads to fibrous encapsulation, which must be overcome by biologic materials placed within them. The osteogenic nature of the nanoLOCK surface may allow a decrease in the use of expensive biologics to obtain implant fixation and fusion at a lower cost per level. We also back the fusion up with an implant warranty, which nobody else does to my knowledge.
Disadvantages: We are a small company that not only has to blaze our own trail by educating on our subtractive surface nanotechnology, but we also have to defend against misleading marketing and competitors that use our scientific papers to promote their own devices but do not have clearance by FDA to make nanotechnology claims. Just because an implant feels rough to the touch does not mean it will interact in a positive manner with cells at the critical nano level.
Significance: Titan Spine seeks to change the landscape of interbody fusions by harnessing the osteogenic power of nanotechnology. We are also bringing titanium, a material that has a long history of success in orthopaedic applications, back to the interbody space. Due to prior threaded titanium implants, there is a misconception that CT imaging and fusion assessment could be negatively impacted. This is no longer the case with the nanoLOCK implants following advancements in design as well as software advancements in imaging. The other implant material misconception is that titanium devices will subside due to a higher Modulus of Elasticity (MOE) than PEEK. MOE is a material property, and is just part of the equation that determines the strength/stiffness of implants. Subsidence is affected more by implant design, including macro surface characteristics, than the material’s MOE.
Greatest challenge companies face in adopting titanium: The greatest challenge competitive companies have in transitioning to titanium is the massive amounts of PEEK inventory on their shelves. Some companies have responded by coating their PEEK implants with titanium, which makes matters worse due to the potential for the generation of loose titanium particles and/or delamination of the titanium from the PEEK during impaction.
Company: Oxford Performance Materials
Product: OsteoFab®, process that combines 3D printing and OXPEKK®
Applications: Spine, craniomaxillofacial
Status: Three OsteoFab products received 510(k) clearance, including SpineFab®, a vertebral body replacement implant for thoracolumbar, in July 2015.
Interviewed: Scott DeFelice, CEO and Chairman
How it works: We have a material (OXPEKK) that is inherently osteoconductive and it has surface deposit reservoirs that are conducive to bone ongrowth; it interlocks.
Regarding the design of SpineFab, one of the things that additive manufacturing (specifically, selective laser melting) allows you to do is create geometries that are impossible or extremely inefficient to create any other way. We have a feature we call OMNILOCK—think of it like towers on top of the implant leaning in all different directions; those support immediate fixation and mechanical interlock for the implant. That is something that is uniquely enabled through additive manufacturing.
You have a highly enabling material, then you have a highly enabling design feature.
Advantages: Everything starts with the right material. As I often tell people who wonder what’s happening with additive manufacturing, a lot of the companies in this space are building with materials that are really useful. Sure, you can build something that looks like an implant with an ABS (acrylonitrile butadiene styrene) and a FDM (fused deposition modeling) process, but you would never put that material in the body. You need to start with a material construction appropriate for the end-use application. In the case of spine, polyketones (PEEKs and PEKKs) have gained favor over the years for their purity, biocompatibility, mechanical properties, ability to be sterilized, and with PEKK, there is the inherit ability to be osteoconductive.
Future: We’re firm believers in the idea that if you want to be effective in the healthcare industry—no matter where you are in the healthcare industry, as a result of the Affordable Care Act and increased pressure on hospitals to own the outcome—the economics are critical. You can’t come out with more clinical efficacy for more money. It comes down to more clinical efficacy for less money. As we practice it, additive manufacturing produces structures extremely economically.
Greatest challenge companies face in adopting a new materials: There haven’t been really fundamental advancements in orthopaedics; they’ve been incremental. I think that’s the combination of the investor community, whether VC-funded or private equity-backed, they’re all risk-adverse with overtones of ”There’s a big market; let’s not change much; let’s just go at that incrementally.” That has been a pressure. Then the regulatory environment, which I don’t think is as daunting as many people think. And there’s a culture and history in the industry that doesn’t want to push too many paradigms—think of things like metal-on-metal; that was an innovation where the materials had an answer that turned out to be the wrong answer.