Shoulder Technology Isn’t Made ‘Off the Cuff’

Two seconds.

That’s all it took for Rudy Kadlub’s world to implode.

Two seconds for his life to forever change (or so he thought).

Two seconds for his career to end (or so it seemed).

Two seconds to utter something Kadlub never imagined he’d hear: “You won’t be able to weightlift anymore.”

Those seven words cut through Kadlub like a knife. He’d been competing as a professional power lifter for 15 years and had amassed more than 30 world records. He was also CEO and co-owner of Portland, Ore.-based Kabuki Strength, one of the world’s leading power lifting and gym equipment producers. 

Power lifting was his passion.

But that zeal was in peril, thanks to Kadlub’s arthritic shoulders, likely (at least partially) the result of years of record heavy power lifting. The recommended treatment was a total shoulder replacement, which would essentially end Kadlub’s power lifting career.

“Though I have had a long and successful career as a homebuilder, power lifting has always been my passion,” Kadlub, currently the world’s strongest over-70 power lifter, recalled in an online blog. “I refused to accept that I could not continue to lead an active lifestyle. There was no way I wanted to step away from it all, retire, and put an end to my power lifting career.”

So Kadlub rejected his doctor’s advice. No surgery.

He forged ahead with his power lifting career, hoisting increasingly heavier weights and setting more world records—all at the expense of his perpetually aching shoulders.

“I continued to work through the pain. It wasn’t easy. All that training, especially the squats and deadlifts, were taking a toll,” he said in the blog. “Over time, the cartilage in both my left and right shoulder joints was wearing out. It was getting to the point that whenever I moved in certain ways, bone hit bone. My range of motion was becoming increasingly limited…Outside of the gym, even simple, everyday tasks were becoming more difficult. You don’t realize how much you use your shoulders until you’re in pain just from trying to put on a shirt.”

Or reach for a dish from a kitchen cupboard shelf.

Opening a patio table umbrella was no picnic, either.

When Kadlub’s glenohumeral osteoarthritis progressed to the point where he couldn’t even put on a coat by himself (both annoying and embarrassing), the strongman returned to his doctor to weigh his treatment options.

This time, however, Kadlub’s physician referred him to a Cleveland Clinic specialist who presented him with an option he couldn’t refuse: A minimally invasive procedure that would repair his arthritic joint yet still allow him to compete as a power lifter.

There was no way Kadlub was passing up that opportunity. He underwent shoulder replacement surgery using technology developed by Bedford, Mass.-based Anika Therapeutics Inc. The company’s alternative remedy to traditional shoulder arthroplasty preserves the joint’s native anatomy using customized implants.

OVOMotion with Inlay Glenoid Total Shoulder Arthroplasty (TSA) System is an anatomic, stemless shoulder solution featuring a non-spherical shaped implant designed to preserve native anatomy and replicate the humeral head shape. According to the company, the OVOMotion TSA System has a lower risk of fracturing and removes less bone and soft tissue than traditional arthroplasty procedures.

OVOMotion TSA also lacks the long stem that conventional implants use to attach to the patient’s arm bone. Consequently, the implant does not change the native anatomy or restrict movements and activities after recovery.

Kadlub underwent total shoulder replacement procedures on both joints six months apart. “I regained my full range of motion and remarkably, had no pain,” he said. “I resumed my training schedule, and six months after my second surgery I was back on the platform, competing in a power lifting competition.”

Six months after that, Kadlub set four world records.

Alternative solutions like the OVOMotion TSA System are increasingly gaining favor these days as non-compromising patients like Kadlub seek to maintain their active lifestyles. To better understand the forces driving the rapidly-changing shoulder replacement market, Orthopedic Design & Technology spoke to several experts over the last month. They included:

• Kristoff Goson, global vice president and general manager, Extremities & Sports Medicine, Zimmer Biomet Holdings Inc.
• Tim Lanier, vice president and general manager, Upper Extremities, Stryker Corp.
• Rajit Kamal, Worldwide president, Sports Medicine & Shoulder Reconstruction, DePuy Synthes, and Matt Holda, senior marketing director, Growth & Innovation, Shoulder Reconstruction, DePuy Synthes.
• Christopher P. Roche, senior vice president, Extremities, Exactech Inc.

Michael Barbella: What trends are driving innovation in the shoulder replacement market? Have these trends changed in recent years?

Rajit Kamal: We are seeing several trends in shoulder replacement, some of which have accelerated in the past few years. First is a shift towards outpatient or ambulatory surgical centers which has generally been seen In Joint replacement procedures. With the shift towards an outpatient setting, efficiency is key and terms of the innovations resulting from this trend, one is fewer trays. How do you make the system a lot more efficient, so that you can have a better turnover? That’s one of the areas we’ve been focused on with the innovations that we have brought to market over the past year. It’s something we plan to scale in 2023 with our INHANCE Shoulder System.

The second trend we’re seeing is a focus on addressing unmet needs in reverse shoulder arthroplasty which accounted for 70% of all total shoulder arthroplasty procedures in the U.S. in 2020. From an innovation perspective, it’s about bringing implants to market that provide more interoperative flexibility. As a majority of shoulder replacements are done by surgeons who do probably 15 surgeries a year, anything that is easier to use is preferred. That’s another area of innovation that we are focused on and we do bring some of that to market with our INHANCE Shoulder System. The third trend we are seeing is the adoption of digital technologies like TRUMATCH Shoulder Planning. The fourth trend I would highlight is the emergence of the shoulder specialist. More surgeons today are now treating the whole continuum of care for the shoulder using a [product] portfolio that covers everything they might need—anchors, sutures, and instruments—to repair a shoulder all the way up to anatomic arthroplasty and reverse shoulder.

Matt Holda: One of the other trends is additive manufacturing. It’s starting to take thinking and designs in a very different direction and helping provide a more personalized approach to patient care.

Tim Lanier: We’re at a point in shoulder replacement where hardware innovation is still unlocking significant advancement in patient outcomes, while at the same time, digital and enabling technologies are accelerating within healthcare. This makes shoulder an extremely exciting market to be a part of within orthopedics, and we’re excited to be pioneering on both fronts. In addition to hardware and digital innovation, trends are shifting toward simplified solutions for complex cases, simplification, data collection and more bone sparing solutions.

Chris Roche: The two trends that have driven pretty much all the innovation in this space over the past decade is 3D printing and the emergence and adoption of CT based pre-operative planning software.
Both have opened the door for creative design solutions for surgeons to help them better treat their patients and recognize and address more challenging deformities. About 15 years ago, Dr. [Joseph P.] Iannotti [M.D., Ph.D.] at the Cleveland Clinic developed CT-based planning software for the glenoid with shoulder arthroplasty. Glenoid component loosening is one of the main reasons a shoulder implant fails and the magnitude of glenoid deformity is a well-known risk factor for loosening, but that deformity is also not readily visible/appreciable intra-operatively, even for the best experienced shoulder surgeon. That all changed with the development of CT-based 3D pre-operative planning software. Today, there’s not a manufacturer in the world that doesn’t provide CT planning software with their shoulder implants. Exactech was the world’s first provider of rTSA augmented baseplates and we saw the adoption of those devices dramatically increase with the simultaneous use of these pre-operative planning software as surgeons are now able to precisely visualize the 3D deformity of the glenoid. Now our usage of augmented baseplates in the reverse total shoulder is >40%.

3D printing has been similarly impactful and has helped reduce the occurrence of aseptic loosening in both the humerus and the glenoid. Previous surface coating manufacturing operations, like plasma coating, are expensive post-machining operations which have limited applications since they require line-of-sight application and also aren’t really able to create a truly porous surgeons, which the bone prefers. Years ago, Zimmer purchased a company that made trabecular metal, basically they spent a lot of money to make a truly porous implant surface and then 3D printing made that process obsolete. Now you can make a surface that is as thick or thin as you want and also as rough or porous as you want. In addition to the ability to create unique coatings, 3D printing opens the door for many creative design features—features which weren’t previously possible to be machined using traditional reductive operations. And because the forces in the shoulder are lower than in the hips or the knees, 3D printing allows you to relatively do a little more creative things in the shoulder, and you see that with some of the stemless humeral designs that are on the market now.

Barbella: What specific challenges are involved in developing shoulder treatment/replacement solutions?

Kamal: The majority of shoulder replacement procedures are done by surgeons who perform about 10 to 15 procedures a year. So, designing a system that is straightforward, easy to use, and efficient is one of the key unmet needs we’ve had in the market. How do we design a system that is easier to use and efficient in the OR? How do you develop something that provides interpretive flexibility so that if a surgeon needs to move from an anatomic to a reverse shoulder [procedure], they are not having to change everything—components, instruments, etc.—which is what we see with many systems on the market right now. That is where the challenge comes in. The other challenge involves surgical technique and designing the implants and instruments to be able to address different surgical techniques. Digital technologies can help with that. Planning and interoperative digital technologies have a much higher value proposition in shoulder because most surgeons do not do a high volume of procedures. We are seeing the adoption of planning and navigation technologies, but navigation is where I think we will see more adoption in the future.

Holda: Working on glenoid is the most challenging part of shoulder arthroplasty for surgeons, and anything that can be done to improve visualization and improve the orientation at which they see the glenoid will really deliver quite a bit of value. The glenoid is located deeper in the shoulder—not only are you working on the bone but there’s a high degree of soft tissue balancing that’s required and enabling surgeons to better visualize the glenoid anatomy to this day remains one of the biggest challenges. One of the things we think about is how we can help surgeons better work on the glenoid, which then ultimately will allow them to better position the implants for each patient.

Lanier: The shoulder is a complex joint. Not only are the biomechanics complex, but there are many deformities and soft tissue dynamics at play with the shoulder. As with most devices, we don’t know the long-term impact of our latest innovations until years after a new technology launches. It underscores the importance of investing and understanding the clinical side of the business. We use our clinical findings to fuel our innovation. That has been a hallmark of our development engine from the very beginning.

Roche: A little more than 150,000 primary shoulder arthroplasty procedures are performed in the U.S. each year. There are about 23,000 orthopedic surgeons in the U.S. but only a third of those, about 7000, will do shoulder arthroplasty in a given year. When you stratify those surgeons by shoulder arthroplasty volume, about 5,000 of those 7,000 surgeons are only doing about one case per month, or so.  Most complications in shoulder arthroplasty are either related to soft tissue quality, infection, or surgical technique, and it’s hard to be an expert at an operation when you are doing it that infrequently. Conversely, there are about 600 surgeons that do 60 or more procedures a year, or two or more per month and then there’s about 250 in the United States that do about two or more per week. So that’s a big dichotomy in surgeon volume which has real implications on the occurrence of technique related failure modes. There are a limited number of fellowship programs. According to the ASES website there are only 30 fellowship programs in United States and each only accepts one or two surgeons per year. So it’s a relatively small group of experts. Because of this reality, the market needs simple solutions and technologies which help surgeons who do shoulder arthroplasty relatively infrequently, to make decisions like the experts.

Another challenge specific to certain surgeons is that these shoulder arthroplasty experts get referred the most difficult cases—so the product solutions that they require needs to be different and more comprehensive to help them solve whatever condition they are trying to treat. So there are two kinds of extremes. Most companies cater their portfolio more to the occasional user, because there is a lot of volume there. My company is a little different, we have created a large number of unique revision products. So there are two different design paths you can take—either simplicity and ease of use, or a comprehensive solution. If you’re a manufacturer and you’ve managed to create a solution for both, then you’ve hit a home run. I think my company did just that for unique products like the humeral reconstruction prosthesis and also the humeral augmented tray.

Michael Barbella: How is [your company] overcoming the challenges presented by the complexity of replacement shoulder designs?

Kristoff Goson: To synergize these disparate needs of patient, surgeon and facility, a shoulder platform must combine strong design characteristics with adaptability. And this adaptability goes beyond patient anatomy. Take our Identity Shoulder System, which was recently cleared by the FDA, for instance. This convertible humeral stem platform adapts to the needs of the patient, with a wide range of implant sizes and proprietary technologies for soft tissue tensioning. It adapts to the needs of the surgeon and has a design that supports a future revision while minimizing the need for stem removal. Combined with our portfolio of glenoid and glenosphere solutions, the Identity platform offers facilities one package for an incredibly versatile, robust shoulder replacement solution. 

Kamal: The INHANCE Shoulder System we launched has a streamlined stemless-first surgical approach designed to take some of the stress out of a shoulder reconstruction. If you make it easier using fewer interoperative steps, that definitely helps the surgeon. The goal is to make this simpler and easier for surgeons to see the glenoid. What does that mean? Well, you don’t want to have a lot of complicated steps, because surgeons don’t do a high volume of these kinds of procedures. So the unmet need requires a solution that is scalable, accurate In terms of more precise execution—and repeatable. If you’re only doing a few shoulder procedures every year, how accurate are your placements? How precise are you in terms of procedure? These factors become areas of opportunity. By making things simpler, you’re reducing steps. With the INHANCE Shoulder System, we can make procedures easier by having fewer instruments. It enables surgeons to execute a [shoulder] procedure in a more repeatable, accurate, and precise way, and digital technologies help enable that as well.

Holda: Instrumentation is very important. We actually have a dedicated instrumentation set for surgeons to help them better expose the glenoid. It’s called GLOBAL ENABLE [Glenoid Exposure System], and it’s something we’ve developed and put quite a significant amount of educational efforts around that to train surgeons.

Lanier: Having clinical data is always an advantage. This provides insights that are essential to guiding the next generation of solutions. Having a tool like Blueprint is a game changer as we look at how we solve problems in 3D. And now, being part of Stryker, our Upper Extremities business has access to resources, capabilities, and technologies that are game changers for the future.

Roche: Exactech is a unique company in this space because we are more of an engineering technology company and a also clinical research company, as opposed to a marketing driven company. We have created the largest non-government shoulder arthroplasty registry in the world and we use that data to drive publications of clinical studies. We also have a data science team to use this clinical data with machine learning to create novel products, like Predict+, the first ML clinical decision support tool for shoulder arthroplasty. 
 
A very large percentage of our customers are fellowship trained shoulder specialists, and we have product solutions who help them on their difficult referred cases and also in revisions. Listening to our customers needs and our desire to help them in their most difficult cases led us to develop numerous unique products. No company has a device like the Humeral Reconstruction Prosthesis or like Humeral Augmented Tray. We were the first to develop rTSA augments back in 2011. And we were the first company to have a platform navigation system for the shoulder, which we launched in 2016 and have performed over 30,000 cases. More than 40% of our shoulder arthroplasty cases worldwide are GPS navigated. It’s a big competitive advantage for us. 

Barbella: In what ways can TSA and RSA be improved upon?

Goson: Shoulder replacement is first and foremost a soft tissue balancing surgery. The biggest improvement may come from quantifying optimal soft tension and then informing surgeons of this data based on implant configuration variables, as well as more minimally invasive techniques to help minimize soft tissue disruption that can affect the recovery time. We believe technologies like Versa-Dial humeral head tensioning and platforms like our Identity Shoulder System are uniquely positioned to inspire evolved conversations on this topic. Additionally, intraoperative technologies that can surgeons with accurate implant component positioning and execution of the patient specific pre-operative 3D plan could be beneficial.  

Kamal: From an implant design perspective, we’ve seen excellent advancements across the orthopaedics industry. But of the areas we can further improve upon, I would say surgical technique because procedure times are quite long and that is mainly due to the damage it can cause to the soft tissue. There are ways for us to be able to do that differently so we can get patients to recover quicker. The other area is adoption of digital technologies.

Holda: With digital technology, surgeons can “perform” procedures virtually before they go into the OR with a live patient. They are able to simulate different implant constructs and positioning with the software to help better optimize where those implants are placed. We will also have a module that adds a soft tissue element so surgeons will be able to understand virtually what will happen to the rotator cuff muscles with various construct configurations ahead of time.

Lanier: That’s an excellent question, and a question that we continue to pursue the answer to every day. Anatomic glenoids loosen over time, and reverses don’t get the full motion of a good TSA. Solve these, and it’s making tremendous progress.

Roche: Anatomic shoulder arthroplasty tries to match the bony anatomy. What you remove in bone you replace in metal exactly, and the thought is that doing so will best balance the patient joint tension. However, with reverse shoulder arthroplasty, you’re not really trying to match the patient’s bony anatomy, instead, you are trying to match the functional anatomy, meaning that you are trying to create a geometry which make the muscles function better. I don’t think we have fully optimized the reverse yet—particularly as it relates to restoring internal and external rotation. There is room for improvement there because the best reverse shoulder doesn’t get as much rotation as the best anatomic shoulder. Regarding reproducing the bony anatomy with anatomic shoulder arthroplasty, there is room for doing that better as well. I think in the coming years you are going to see more companies provide customized options, and not just for the extreme deformity cases.