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The success of an orthopedic implant hinges on numerous factors, from design to fit to the patient’s overall health. A traditional orthopedic implant system includes a variety of implant sizes to help find the best fit. But patient-specific, or personalized or custom, implants can be designed and manufactured with extreme precision to match a patient’s unique anatomy and perhaps provide a better recovery and outcome.
Three-dimensional modeling through the use of CT scans, MRIs and radiography has been utilized for decades in the orthopedic space. Today, improvements in these technologies and design software mean that anatomical structures can be reconstructed more accurately in the creation of custom implants.
“Patient-specific implants have the potential to revolutionize orthopedics as we know it by personalizing the treatment based on each patient’s unique situation,” said Benjamin Johnson, VP, Portfolio & Regulatory, Healthcare at 3D Systems. “The detailed clinical evaluation and treatment planning that occurs with patient-specific implants can improve surgery by decreasing medical errors, shortening procedural times, and preventing revision surgeries.”
3D Systems DMP Triflange Bone Model
Patient-specific implants are a growing and advancing field within orthopedics thanks to the benefits they provide. As with most orthopedic solutions, the closer an implant can mimic the natural body, the better — and every body is different.
Seeing the surgical benefits and potential for these implants, some manufacturers seek to make them more mainstream. Today, we see this mainly in joint replacement. Additionally, major manufacturers, software companies and hospitals partner to produce custom implants for unique cases like deformities and traumas.
Many in the industry believe that the proliferation of additive manufacturing, robotics, augmented reality and artificial intelligence in orthopedics will greatly expand the accessibility of patient-specific implants.
“We believe that bespoke implants are superior to generic implants from an efficiency standpoint,” said Douglas Unis, M.D., Founder & Chief Medical Officer of Monogram Orthopaedics, and a joint replacement surgeon at Mount Sinai Health System. “With 3D printing, the incremental costs to customization are increasingly marginal and, when combined with robotics, companies can materially lessen the inventory and reprocessing burden.”
It may seem, then, that patient-specific implants are the answer. But there is a lot at play — designing the implant, manufacturing it and shipping it in a timely and cost-efficient manner. In addition, patient-specific implants face reimbursement and surgeon acceptance hurdles.
The ultimate question is: Knowing the benefits that customization provides, what will it take to overcome these hurdles and scale adoption of these devices? First, we examine the different approaches companies are taking to personalize implants.
Varying Approaches to Patient-Specific Implants
Just like the very premise of bespoke implants, the concept itself is not one-size-fits-all.
“The most challenging aspect of customization is accounting for intraoperative adjustments to the surgical plan,” Dr. Unis said. “Many surgeons rightfully describe total knee arthroplasty as a soft tissue surgery. Properly balancing the soft tissues is essential and often requires intraoperative tweaks to the surgical plan. Companies will need to be very thoughtful about surgical techniques and how technology like robotics can help mitigate these challenges. We don’t believe in customization for marketing purposes; customizations must benefit patients. We think companies need to be very thoughtful about what they customize.”
This strategic and purposeful approach means looking more deeply into when a customized implant makes sense for the patient. It will also determine a company’s process for manufacturing the implant, which varies across organizations.
Conformis is a knee and hip replacement company that uses its proprietary iFit Image-to-Implant technology platform to develop and manufacture implants that are individually sized and shaped for the patient. They use data gathered since 2007 to study implant effectiveness and to inform improvements.
Conformis Identity Knee (left) and Imprint Surgery in a Box (right)
“For a little over a decade in over 100,000 patients now, we’ve been building a database,” said Mark Augusti, President and CEO of Conformis. “We’ve been building a bibliography of clinical outcomes and all of the studies we’ve done. The benefits of custom implants are faster recovery, shorter hospital stay, and more bone preservation, which leads to less pain and results in better functional outcomes.”
With Conformis, the physician must first order a CT scan, which is then transmitted to the company. Conformis then uses their software to design the actual implant with its own serial number that is added to the database.
“We have a design history file for every patient and all our software has been FDA cleared,” Augusti said. “First we do a leg measurement to get the right alignment, then we build the femoral component and the tibial component. And then based on that, we build what we call the PSI or the personalized surgical instrumentation, which is our 3D-printed cutting guides to actually execute the plan.”
A preoperative plan is then given to the surgeon along with the custom implant and instrumentation.
Monogram, which has yet to reach market, will use software to identify SKUs from an extensive database of options that are best suited for a particular patient. They do not customize features like the locking mechanisms or inserts, and the manufacturing process is similar to conventional methods.
“For regulatory and IP reasons, we have to be precise with what we mean by a custom implant,” Dr. Unis said. “Our interpretation is that a custom implant is made or done to order for a particular customer, i.e., the SKU didn’t exist until someone made it for the patient. With 3D printing and software, we can effectively create infinite sizing options that already exist before a patient case gets generated.”
Monogram already has implemented a preoperative planning pipeline that leverages machine learning to prepare the surgical plan (segmentation, anatomical landmarks, etc.). They have not yet implemented an automated workflow for implant selection, though that is planned for the future.
Hospital for Special Surgery (HSS) and LimaCorporate are in the midst of launching an onsite 3D printing lab for custom implants. Their process is less focused on scalability and more on the convenience and accuracy of implants for complex cases.
“Having a 3D printing manufacturing facility close to clinicians allows for collaboration that would not otherwise be possible,” said Mathias Bostrom, M.D., a hip and knee surgeon at HSS. “It also facilitates and optimizes the timing from manufacturing to implantation. The feedback between the engineers and clinicians is almost immediate. This will ultimately enhance the field significantly.”
Due to the COVID-19 pandemic, the ramp-up to use the facility has been slowed. Once regulatory issues have been resolved, Dr. Bostrom anticipates HSS being able to use this facility to manufacture custom implants.
“We already have a number of implants that are in the design phase and will be manufactured shortly,” he said.
FDA recently announced that it was evaluating different frameworks for point-of-care manufacturing. There are different scenarios based on who designs the device, who manufactures it and who assumes the regulatory risk. It’s generally thought that once a regulatory framework is outlined, point-of-care manufacturing could revolutionize patient-specific implants in orthopedics.
FusedBone, an Amsterdam-based software company focused on additive manufacturing workflows at the point of care, is also betting on the future of custom implants.
“We study and understand the rules and regulations regarding additive manufacturing for different classes of medical devices at the point of care. We digest them. And then, we put them in an understandable, easy to follow process for the team at the point of care to use and go through,” said Navid Ardakanian, CEO and Co-Founder of FusedBone.
Ardakanian believes that the European market is experiencing a paradigm shift, where more hospitals are implementing an additive manufacturing lab onsite. The shift is happening because of various factors, including the availability of new materials and the fact that 3D printing machines are now more affordable. Many hospitals also have biomedical engineers on staff who could design devices inhouse.
“The most confusing part for hospitals is often the regulations,” Ardakanian said. “The biggest value that we bring to our customers is that we understand the regulations and put them into the system in conjunction with the ISO standards, the necessary documents that need to be created, the document management and the document archiving standards into one single workflow. You plug in your 3D printers, you set up the software, and you’re ready to go.”
FusedBone’s is also a crowdsourcing system for best practices in onsite custom implant manufacturing. Similar to how Conformis is gathering case data in regard to implant design and patient outcomes, FusedBone is tapping into machine learning to synthesize users’ best practices to create a more efficient process.
“A hospital doesn’t need to worry about updating the system or workflow when the workflow is continuously being updated by the best practices,” Ardakanian said. “The system is continuously evolving. It’s a dynamic system that taps into the knowledge of every hospital, every scenario, every institution that is using the system.”
FusedBone is currently operating only in Europe. But the company is looking to expand internationally in the near future to support hospitals looking to 3D-print custom implants inhouse.
Challenges and Opportunities in the Market
Personalized implants include two camps with names that industry often uses interchangeably. Custom implants is a term associated with truly complex orthopedic cases. Patient-specific implants are often those created to bring incremental improvement to more routine orthopedic surgeries. Each brings its own regulatory, reimbursement, design, manufacturing and overall cost hurdles. Still, numerous stakeholders believe that if certain challenges can be overcome, these implants offer a great opportunity for the future of orthopedics.
Similar to FusedBone, 3D Systems is developing workflow tools that are easier to use, require less specialized expertise and utilize machine learning algorithms for continued improvement. This technology, coupled with the increasing availability of new materials and 3D printing machines, offers the patient-specific implant market opportunity in both cost and quality.
“The technology surrounding the patient-specific workflow continues to improve and become increasingly automated, which will help to reduce costs,” Johnson of 3D Systems said. “To tackle the challenges presented with patient-specific implants, companies need to first develop a robust business strategy to understand how they will develop and deploy products. Once a vision is established, companies can then partner with suppliers like 3D Systems to help accelerate product development and commercialization.”
Conformis was founded in 2004. The company’s personalized knee replacement and hip replacement solutions continue to face reimbursement and surgeon adoption challenges. Part of the reason is implant cost.
The company is offering a premium product in a market where reimbursement continues to decline, Augusti said. Therefore, it costs more to use a Conformis implant over others on the market.
“Another headwind for us was just the way surgeons are trained in the major academic centers. They’re used to having a lot of different options,” Augusti said. “There was never much of a financial incentive for the surgeons. They would step back and say, ‘What’s in it for me? I think I’m a pretty good surgeon today. My patients are pretty happy. I’m booked out a few months. So I don’t buy the story that I need a custom implant.’”
However, with challenge often comes opportunity. Conformis recently announced a model that can be described as “semi-custom” or a hybrid set of implants, which addresses some of the major personalized implant challenges head-on. Using their custom design data, they have developed 12 implant sizes for total knee replacement that are a better fit than standard implants, but not wholly custom. This is an in-between offering that provides better outcomes without the premium designation.
Dubbed Imprint, Conformis’ new model provides the intraoperative flexibility that surgeons were used to, and hits lower price points and faster delivery times. They still offer fully customized implants at a premium. The company’s recently introduced Platinum Services Program (PSP) creates a financial incentive or opportunity for patients to be able to pay out of pocket to get a fully personalized implant.
“Nobody’s built an implant system off this many anatomical samples like we have with the 100,000-plus designs that we’ve done,” Augusti said. “We’ve compared that up against the 85,000 scans that we use to develop it, and within a set criteria, we meet those patients’ measurements up to 92.5% of the time. So the surgeon has fewer compromises to make with our system.”
Some of the biggest opportunities for growth in customization are with instruments, both personalized instrumentation and robotics, according to those we interviewed.
“Traditionally, many of the more surgically complex orthopedic cases would utilize patient-specific instruments and implants, but the trend toward using these solutions on more common procedures is occurring,” Johnson said. “Capitalizing on the opportunity is best done in a stepwise fashion by establishing patient-specific workflows for producing surgical instrumentation designed to prepare the anatomy to receive a stock implant. The same workflow and the lessons learned with patient-specific instrumentation can then be leveraged for implants.”
Advanced robotics are said to offer surgical precision, and offer a significant opportunity for growth in orthopedics, and specifically patient-specific implants.
“The reason robotics is so essential is because custom implants of the future will be uncemented and will rely on precise bone preparation,” Dr. Unis said. “Furthermore, more and more surgeons are focused on soft-tissue balancing and we do not believe patient-specific instruments can address these demands.”
Debate abounds about the cost effectiveness and improved outcomes with robots. But one obvious benefit of robotics is their high precision. And they play to the increasingly educated and savvy patient.
“Robots still have to prove that they make a difference clinically,” Augusti said. “But if you think about the ultimate thing a patient could want, the ultimate premium offering would be a customized implant put in with a robotic execution.”
Will Increased Demand Necessitate Scalable Production?
Now the golden question: Will personalized implants overcome their manufacturing, regulatory and overall cost hurdles? And if so, will they become the new standard, therefore necessitating massive scale-ups to meet demand?
The industry doesn’t seem to have a solid answer to that question. And, not everyone sees the same future for custom implants. Dr. Unis and Dr. Bostrom don’t see widespread adoption in the near term. Johnson, Ardakanian and Augusti are more optimistic.
“I don’t see custom implants as being used in the mainstream, and they will remain a niche part of parts of arthroplasty,” Dr. Bostrom said. “3D printing manufacturing techniques are already being used for the manufacturing of standard implants. The use of patient-specific guides could become more mainstream once the process of designing these becomes more automated.”
Dr. Bostrom sees benefit with fewer surgical trays required in the operating room. But as far as common surgeries go, he doesn’t find it likely that patient-specific implants will be produced at HSS’ onsite 3D printing lab.
“I don’t think we will be manufacturing a large number of standard implants for typical cases here at the Hospital for Special Surgery,” he said. “However, all the major and some niche implant manufacturers are using 3D printing manufacturing techniques in many of their more standard implants.”
Dr. Unis anticipates that customized implants will certainly become more prevalent, but it may take a bit longer.
“We do not expect customized implants to have a significant share of the joint reconstruction market in the next five years. Adoption of novel implants will take time and will require clinical substantiation and continued robotic adoption, and we think a more realistic timeframe will be 10-15 years,” Dr. Unis said. “We believe the first step will be the ubiquitous utilization of robotics and press-fit implants. As press-fitting knees with robotics becomes ubiquitous, it will open the door to custom implants. Data that companies like Monogram have shown in the lab will need to translate to clinical outcomes.”
Dr. Unis believes that the incremental cost to customization will become less significant over time, and the cost savings from streamlining inventory and reprocessing will become more critical. If the clinical data substantiates custom press-fit implants, he thinks it is likely that this portion of the orthopedic implant market will expand in the future.
Augusti is of a similar mindset, though he believes the movement is further on its way.
“There is this trend where patients want personalization,” Augusti said. “I believe the future is right for custom implants because we’ve changed the model now where we’ll be able to bring it to market and be able to get paid for providing a premium service. And I think the data suggests that, in the long run, about 30% of the patients will choose to upgrade.”
Again, though, he recognized the need for further technology advancements and a flattening of the steep cost curve before custom implants become commonplace. This is an inevitable, he believes, but a necessary step before mass commercialization.
“I’m a big believer in innovation and technology,” Augusti said. “As the cost of robotics, digital tools and augmented reality comes down, that’ll offer opportunities to make the custom implants more available to other people to potentially change the dynamics in surgery.”
Augusti added that the single biggest improvement in the personalized implant process – and the most significant way to reduce cost – will be the full integration of AI and machine learning.
He predicts that if there is a breakthrough in cost by even a couple hundred dollars, custom implants could become standard. But it could be 10 years.
Johnson and Ardakanian are all in with the custom implant market outlook, with high expectations in the immediate future. The cost factor and the need to streamline the manufacturing process are again the major hold up for greater adoption of these implants.
“Within five years, I believe there will be an explosion of patient-specific orthopedic implants on the market with indications from head to toe,” Johnson said. “Within this timeframe, I anticipate we will have a better understanding of the cost/benefit ratio, and payors will specifically reimburse these devices. In several anatomies, I envision patient-specific implant solutions to increasingly become the standard of care, with more hospitals bringing implant manufacturing capabilities in-house.”
Other applications and industries are showing this to be true on a smaller scale, perhaps shedding light on what’s to come in orthopedics.
“I expect patient-specific surgery, and the associated implants used in reconstruction procedures, to become mainstream across orthopedics,” Johnson said. “The anecdotal evidence we see in the dental and craniofacial markets gives us reason to believe that the benefits of these solutions outweigh the costs. I expect that patients and surgeons will increasingly demand access to these products.”
Whether it happens sooner or later, the general consensus is that patient-specific implants are here to stay. The current challenges may be overcome if market factors align, which can happen if demand is high enough. But it’s not an overnight process.
“I think it’s going to take time. I think that 3D metal printing is still very expensive. The printers, the devices themselves are expensive,” Augusti said. “But as soon as the printers can out compete the foundries on price and efficiency, I think it’ll take off and it’ll be a more interesting process.”
