Mark Crawford, Contributing Writer02.08.21
A growing market exists for new and innovative surgical instruments that improve the end-user experience—for both surgeons and patients. This growth is especially driven by new instruments for minimally invasive procedures. In December 2020, MarketWatch reported the global minimally invasive surgical instruments market is expected to exceed $26 billion by 2024 at a compound annual growth rate of 12 percent over that period.1
Instruments are broadly categorized as any individual tool or complete system that helps the surgeon, operating room team, and healthcare system secure the implant in the patient to achieve the best possible outcome.
“We typically classify an instrument as anything in the surgical tray that isn’t implantable,” said Dean Poulos, sales and marketing manager for Gauthier Biomedical, a Grafton, Wis.-based designer and manufacturer of surgical instruments. “It could be a hand-held device or a measuring device such as a template or guide. In a knee surgery, for example, there are femoral sizers that help surgeons select the appropriate implant size. For spinal fusion, rod templates help surgeons determine the shape and length of the implantable spinal rod. All these devices are part of a well-planned ensemble that facilitates an efficient and successful surgical procedure.”
Although medical device manufacturers (MDMs) still prefer simpler designs and ease-of-use when possible, surgical procedures increasingly require devices with complex geometries, tight tolerances, miniaturized sizes, and surface treatments and coatings. MDMs are also very keen on rapid design iterations and shorter timelines, which often require advanced manufacturing technologies to achieve. With added pressure from healthcare systems to reduce healthcare costs, OEMs are also paying more attention to instrument lifecycle management, including packaging, sterilization, tracking, and logistics. More surgical procedures are being performed at smaller medical centers, such as outpatient ambulatory surgical centers (ASC), where reimbursement rates are lower. For cost efficiencies, these environments are using more single-use and surgery-ready instrument sets, especially for lower-complexity implant procedures.
Latest Trends
The geometries of orthopedic devices are becoming increasingly unconventional. Their high-precision, complex designs and shapes are often driven by human anatomy, or a surgeon’s need for ergonomic access. These unconventional (and often miniaturized) shapes, where nothing is round or square, force MDMs and their contract manufacturers (CMs) to create unique fixtures to hold parts, which drives up costs. There is also a strong trend toward using robotics for extremities, spine, and other surgical procedures. All these technology advances typically require tightly controlled dimensions, often with submicron tolerances. As a result, OEMs are relying more on geometric dimensioning and tolerancing (GD&T). With surgical instruments in particular, multiple parts must fit together with the highest precision and everything in a surgeon’s tool tray must work together flawlessly.
“As GD&T usage becomes more advanced, it can be open to interpretation, which increases the need for excellent communication between the OEM’s design engineers and the supplier’s manufacturing engineers,” said Randy Sible, general manager for Tegra Medical, a Franklin, Mass.-based contract manufacturer of medical devices and components for the orthopedic market. “Everyone needs to be on the same page when it comes to determining the part that is used as a reference for tolerance calculations and where to measure from. Problems arise when the designer has a different interpretation of tolerance than the manufacturer.”
To maximize communication, reduce risk, and get to market faster, more OEMs are taking a collaborative approach with their CMs to design and develop surgical instrumentation. Increasingly, CMs are expected to provide inputs to design and manufacturability earlier in the design process. This includes being involved in preliminary risk mitigation measures through process failure mode effects analysis, validations, capability studies, and design for manufacturability (DFM).
“More OEMs are understanding that the contract manufacturers are the process experts and they welcome their expert DFM recommendations,” said Dave Leibel, engineering manager for rms Surgical, an Anoka, Minn.-based provider of medical device instrumentation and sterilization cases and trays. “These recommendations may be incorporated into the design intent of the product, thereby expediting product development and avoiding unnecessary prototype and testing costs. This is especially true with complex component designs.”
The COVID-19 pandemic has presented many challenges to the orthopedic industry. Travel restrictions impacting the traditional in-person meetings and facility visits have affected the ability to establish and maintain effective communication between OEMs and their contract manufacturers. Relying on video platforms for virtual meetings, as well as virtual reality/augmented reality software to present models and designs, have become effective product development tools.
“The use of virtual mediums like Microsoft Teams has enabled us to increase our presence both domestically and internationally and often has shortened the amount of time it takes to move a project through development,” continued Leibel. “From a product quality standpoint, traditionally some customers require ‘witness’ first article inspections to be done on site at the manufacturing facility. In those instances, we have been utilizing Google Glass technology to perform these tasks virtually to replicate an in-person experience. This has worked very well and our team is exploring other opportunities to use this technology elsewhere in the manufacturing process.”
What OEMs Want
Cost pressures from OEMs to their supply chain partners has significantly increased—not only for parts, but also costs for the entire project. Therefore, OEMs are asking their CMs to get involved earlier in the design process to help reduce costs and get the product to market as quickly as possible.
“We are now asked to provide input and budgetary estimates before the design and engineering drawings are finalized,” said Leibel. “In situations where financial obstacles may be present, it is best to analyze design inputs and evaluate cost reduction methods early in the design process, when there is still the flexibility to make changes relatively easily. Design changes become more difficult, and often expensive, if they need to be incorporated later in the design process.”
Another cost-reduction strategy is finding ways to get products to market more quickly. OEMs often request quick turnaround for prototypes and shorter production lead times. There is also more interest in single-use (disposable) devices, which are increasingly viewed by OEMs as a way to deliver high performance at lower cost, while also reducing the risk of healthcare-associated infections.
“We are definitely seeing significant movement toward single-use, surgery-ready kits and instruments that can improve OR productivity, cut costs, and reduce carbon footprints,” said Lane Hale, president of ECA Medical, a Thousand Oaks, Calif.-based designer and manufacturer of single-use instrumentation and surgery-ready procedural kits. “The advent of new types of plastics also helps lower costs while providing the robustness of metal, creating very strong instruments that meet the most demanding loads and stresses.”
Making an Instrument
Instruments, whether single-use or reusable, are often complicated to design and manufacture. They can be complex assemblies that utilize a range of materials and involve multiple processes, including precision machining, injection molding, welding, cleanroom assembly, testing, packaging, and sterilization.
Often a device is used in combination with two or three other instruments at the same time, making it imperative they work together with the utmost precision. This typically requires machining tolerances that are tighter than tolerances for products. “With spinal surgeries for example, a ratcheting screwdriver’s handle will come with a quick connector to lock onto various surgical instruments,” said Poulos. “The ratcheting screwdriver handle must offer very precise driving performance and, at the same time, retain the various modular instruments it attaches to. This creates the need for the two devices to fit together seamlessly, without any unintended movement or play. We design our ratchets and our quick connectors to be very precise to help surgeons perform surgeries better and safer.”
Reusable orthopedic instruments are some of the most complicated devices in the medical world. They can have many components, complex assemblies, and moving parts. For example, a retractor can have 70 components or more. All these different parts must work perfectly together. The design complexity of reusable instruments is not, however, the biggest challenge for CMs—instead, it is how to manufacture them efficiently, when their volumes are limited. OEMs place big orders when first launching a new reusable product; subsequent orders get smaller and smaller because the instruments stay in use. On the other hand, disposable instruments and implants are consumable, so there is a larger return on the investment (ROI) for CMs for these products.
“While it can make sense to purchase specialized machines and gauges when a steady stream of orders is expected, there may not be an ROI to do so for a reusable instrument order,” said Sible. “To keep costs down for the OEM, the supplier might need to rely on fixtures and equipment that can be used for a variety of products. The final product is the same, but the path for getting there is more difficult.”
New Technologies
CNC machines continue to improve, with more axes that allow the machining of complex components in a single setup, with easier user interfaces. Micromachining with femtosecond lasers—especially for creating tiny, complex parts and surface textures—is often the only way to make some of these parts and products. Robots on the manufacturing floor are now becoming so easy to use that they do not require engineers or dedicated technicians to program them. Collaborative cobots can now work safely in the presence of human workers.
Tegra Medical, for example, is using cobots in its factories to perform some of the most repetitive tasks efficiently and consistently. The robots have built-in sensor/optical safety systems that make them automatically stop operating if they encounter objects or people in their workspace. “This enables our workers and robots to work side by side, creating a collaborative work relationship between the robot and operator,” said Sible.
Advanced materials have a key role to play in the design of next-generation surgical instruments. OEMs have greater expectations of their raw material suppliers for top material quality, reliability, and performance—especially durability, hardness, and strength.
Reusable orthopedic surgical instruments must withstand harsh environmental conditions during cleaning and reprocessing. In addition, these devices manipulate bone and have extreme forces imposed on them during use. These factors require them to be made from robust materials that can handle these kinds of physical, thermal, and chemical stresses throughout their expected useful life. “This robustness often translates into harder materials that can be challenging to machine,” said Eric Walker, senior technical sales engineer for MedTorque, a Kenosha, Wis.-based manufacturer of instruments and implants for orthopedic and spine surgery. “This is especially true when tight tolerances or unique features are required.”
For example, 455/465 stainless steel is used for many components, including driver shafts and taps. Although it is strong and durable, it can be difficult to machine, especially for long shafts. It also has a shrinkage factor after heat treatment that needs to be considered before machining. 17-4 bar hardened stainless steel is another common steel that is challenging to process.
As an alternative, Carpenter Technology Corporation, a Philadelphia, Pa.-based provider of specialty alloy-based materials and process solutions for the medical device market, has developed a 17-4 bar product with significantly reduced residual stresses, which can sometimes cause out of tolerance instruments. “As a drop-in replacement for existing 17-4 products, this low-stress bar feedstock will increase machine throughput and decrease non-conforming instruments,” said Gaurav Lalwani, applications development engineer for Carpenter Technology. “The reduced residual stresses in the product translate to better machining performance and can help reduce the high scrap rate of 25 to 50 percent that often occurs when using the conventional 17-4 product.”
New coating materials that enhance the performance of surgical instruments continue to come into the market. For example, Picosun Group, a supplier of atomic layer deposition (ALD) thin-film coating solutions, is working with Chinese hospitals to test its ALD technologies as a way to create safer surgical procedures.2 Electrosurgical equipment uses high temperatures to cut and separate tissue, simultaneously coagulating blood. Tissue and blood sticking and burning on the blade during surgery can increase bleeding, tissue damage, tearing, and scarring. Picosun’s ALD technology can be applied as ultra-thin, pinhole-free coatings over an anti-adhesive micropatterning of the surgical blade, preventing blood and tissue from sticking to the blade.
Although the main focus for additive manufacturing (AM) has been orthopedic implants, there is increased interest from OEMs and CMs in printing patient-specific, custom surgical instrumentation. “For instance, a 3D-printed, patient-specific custom surgical guide can be highly advantageous in navigating a complex surgery,” said Lalwani. “For such applications, the choice of materials goes beyond regular titanium grades into alloys such as 17-4 PH, Custom 465, and other stainless material systems that our additive division produces in powders routinely used in the production of surgical instruments.”
3DEO, a Torrance, Calif.-based technology company, invented a patented metal 3D printer specifically for high-volume serial production. The process uses CNC machining on a layer-by-layer basis. The printer spreads a layer, then uses CNC to cut the perimeter of the part and any internal features, and then repeats the process by spreading another layer. 3DEO’s process achieves the design freedom of additive manufacturing because it builds parts on a layer by layer basis—yet it also achieves the precision and repeatability of CNC machining because that process is used to define the parts in the layer. The “green” printed parts are then sintered to full density in a furnace. The technology is ideally suited for small and complex metal components for surgical instruments and medical devices. For example, the company recently worked with an OEM to improve the design on a small, complex part used in a “bone scraper” instrument in 17-4 PH stainless steel. This product was not a direct replacement to their existing part, but rather a more complex design that could only be made with 3D printing. “The design is not achievable with traditional manufacturing methods,” stated 3DEO president Matt Sand. “The previous design was expensive to make with CNC machining—with 3D printing, we were able to optimize the design and reduce the cost by 50 percent compared to direct metal laser sintering, with no tooling costs.”
One of the most vexing issues for many MDMs is the maintenance and service life of mechanical torque limiting devices. Some have a comprehensive system to manage the usage of their devices and can return them to the manufacturer for recalibration on a routine schedule. Other OEMs prefer to simply dispose of the devices as service life is nearing the end. The FDA has been resolute in its efforts to monitor and ensure OEMs are adhering to some type of effective plan.
Gauthier Biomedical recently received 510(k) clearance for the IntelliTORQ, a patented electronic torque device that requires no recalibration or maintenance. It uses a Bluetooth-equipped electronic torque sensor to link to the cloud, navigation equipment, or a tablet. “This sterile, single-use device has a tolerance of ±5 percent and can store real-time data, as well as provide real-time feedback for the surgeon,” said Poulos.
Finding a Balance
OEMs and their CMs continue to search for ways that balance quality, technology, speed, and cost. These include searching for materials that provide better strength and corrosion resistance. For example, Carpenter Technology is developing several new materials, including high-nitrogen versions of 400 series stainless products and enhanced chemistry versions of the PH stainless family (17-4, Custom 455/465). “We also have been exploring new material solutions around the cutting instrument space,” said Lalwani. “Our newest material development, A-21, is an advanced carburizing and nitriding stainless steel that exhibits stainless behavior after carburizing, with high case hardness and deep case depth, making it suitable for knife blade and cutting tool applications.”
Depending upon the manufacturing processes being used, dimensioning schemes and tolerances can significantly drive part cost without effectively contributing to the overall device function. In-process quality requirements and unique/special processing methods can reduce throughput, add labor costs, and potentially increase scrap. “By identifying these issues and limitations to the OEM early, it is quite possible to achieve an improved product design that captures all of the design input requirements, in a more cost-effective manner,” said Leibel.
The challenge for many manufacturers is not so much meeting validations—they have had many years to hone these skills. Instead, the challenge is getting OEMs to recognize the value in improving a process, and approving the extra investment or cost. When the CM sees an opportunity to improve a process, especially for a product it has been manufacturing for years, the customer is often reluctant to change anything about the process because of the up-front costs. “For example, if you’re making a 10-year-old product, chances are there are newer, better machines to make it on,” said Sible. “But you’re locked into the original process. Any change, even to a better machine, would require another set of validations, which can be more cost than the customer can justify.”
Many OEMs have expectations for cost downs over the life of a product, noted Leibel. These are typically absorbed by the supplier through continuous improvement efforts. When a change can result in a direct cost reduction to the OEM, the activity often gains momentum and gets managed through the supplier’s change notification process. However, there are often changes a manufacturer can make that do not necessarily result in a direct cost reduction for the OEM, but instead improve product quality, employee safety, delivery metrics, and more. “When these activities do not have a direct path to cost reduction, it can be difficult for OEMs to support the changes through their quality systems,” said Leibel. “OEMs need to appreciate the impact they can have on their contract manufacturers when they are unable to implement potential continuous improvement efforts, either based on available resources or low priority.”
Sible agreed.
“An OEM’s expertise is in design, not manufacturing, so it may not occur to the engineers that something can be made more efficiently in an unexpected way,” said Sible. “They don’t always understand that combining different technologies can be more efficient than using just one.”
For example, Tegra Medical makes an assembly for an orthopedic instrument that requires 78 steps, including cutting the blanks, cleaning, and grinding. “The OEM might think it is impossible to make it efficiently with so many steps, but the reality is that doing it this way lets us make the product in high volume for less than it would be to machine it from a solid block. This is why it is so critical to involve trusted suppliers early in the DFM process.”
References
Mark Crawford is a full-time freelance business and marketing/communications writer based in Madison, Wis. His clients range from startups to global manufacturing leaders. He also writes a variety of feature articles for regional and national publications and is the author of five books.
Instruments are broadly categorized as any individual tool or complete system that helps the surgeon, operating room team, and healthcare system secure the implant in the patient to achieve the best possible outcome.
“We typically classify an instrument as anything in the surgical tray that isn’t implantable,” said Dean Poulos, sales and marketing manager for Gauthier Biomedical, a Grafton, Wis.-based designer and manufacturer of surgical instruments. “It could be a hand-held device or a measuring device such as a template or guide. In a knee surgery, for example, there are femoral sizers that help surgeons select the appropriate implant size. For spinal fusion, rod templates help surgeons determine the shape and length of the implantable spinal rod. All these devices are part of a well-planned ensemble that facilitates an efficient and successful surgical procedure.”
Although medical device manufacturers (MDMs) still prefer simpler designs and ease-of-use when possible, surgical procedures increasingly require devices with complex geometries, tight tolerances, miniaturized sizes, and surface treatments and coatings. MDMs are also very keen on rapid design iterations and shorter timelines, which often require advanced manufacturing technologies to achieve. With added pressure from healthcare systems to reduce healthcare costs, OEMs are also paying more attention to instrument lifecycle management, including packaging, sterilization, tracking, and logistics. More surgical procedures are being performed at smaller medical centers, such as outpatient ambulatory surgical centers (ASC), where reimbursement rates are lower. For cost efficiencies, these environments are using more single-use and surgery-ready instrument sets, especially for lower-complexity implant procedures.
Latest Trends
The geometries of orthopedic devices are becoming increasingly unconventional. Their high-precision, complex designs and shapes are often driven by human anatomy, or a surgeon’s need for ergonomic access. These unconventional (and often miniaturized) shapes, where nothing is round or square, force MDMs and their contract manufacturers (CMs) to create unique fixtures to hold parts, which drives up costs. There is also a strong trend toward using robotics for extremities, spine, and other surgical procedures. All these technology advances typically require tightly controlled dimensions, often with submicron tolerances. As a result, OEMs are relying more on geometric dimensioning and tolerancing (GD&T). With surgical instruments in particular, multiple parts must fit together with the highest precision and everything in a surgeon’s tool tray must work together flawlessly.
“As GD&T usage becomes more advanced, it can be open to interpretation, which increases the need for excellent communication between the OEM’s design engineers and the supplier’s manufacturing engineers,” said Randy Sible, general manager for Tegra Medical, a Franklin, Mass.-based contract manufacturer of medical devices and components for the orthopedic market. “Everyone needs to be on the same page when it comes to determining the part that is used as a reference for tolerance calculations and where to measure from. Problems arise when the designer has a different interpretation of tolerance than the manufacturer.”
To maximize communication, reduce risk, and get to market faster, more OEMs are taking a collaborative approach with their CMs to design and develop surgical instrumentation. Increasingly, CMs are expected to provide inputs to design and manufacturability earlier in the design process. This includes being involved in preliminary risk mitigation measures through process failure mode effects analysis, validations, capability studies, and design for manufacturability (DFM).
“More OEMs are understanding that the contract manufacturers are the process experts and they welcome their expert DFM recommendations,” said Dave Leibel, engineering manager for rms Surgical, an Anoka, Minn.-based provider of medical device instrumentation and sterilization cases and trays. “These recommendations may be incorporated into the design intent of the product, thereby expediting product development and avoiding unnecessary prototype and testing costs. This is especially true with complex component designs.”
The COVID-19 pandemic has presented many challenges to the orthopedic industry. Travel restrictions impacting the traditional in-person meetings and facility visits have affected the ability to establish and maintain effective communication between OEMs and their contract manufacturers. Relying on video platforms for virtual meetings, as well as virtual reality/augmented reality software to present models and designs, have become effective product development tools.
“The use of virtual mediums like Microsoft Teams has enabled us to increase our presence both domestically and internationally and often has shortened the amount of time it takes to move a project through development,” continued Leibel. “From a product quality standpoint, traditionally some customers require ‘witness’ first article inspections to be done on site at the manufacturing facility. In those instances, we have been utilizing Google Glass technology to perform these tasks virtually to replicate an in-person experience. This has worked very well and our team is exploring other opportunities to use this technology elsewhere in the manufacturing process.”
What OEMs Want
Cost pressures from OEMs to their supply chain partners has significantly increased—not only for parts, but also costs for the entire project. Therefore, OEMs are asking their CMs to get involved earlier in the design process to help reduce costs and get the product to market as quickly as possible.
“We are now asked to provide input and budgetary estimates before the design and engineering drawings are finalized,” said Leibel. “In situations where financial obstacles may be present, it is best to analyze design inputs and evaluate cost reduction methods early in the design process, when there is still the flexibility to make changes relatively easily. Design changes become more difficult, and often expensive, if they need to be incorporated later in the design process.”
Another cost-reduction strategy is finding ways to get products to market more quickly. OEMs often request quick turnaround for prototypes and shorter production lead times. There is also more interest in single-use (disposable) devices, which are increasingly viewed by OEMs as a way to deliver high performance at lower cost, while also reducing the risk of healthcare-associated infections.
“We are definitely seeing significant movement toward single-use, surgery-ready kits and instruments that can improve OR productivity, cut costs, and reduce carbon footprints,” said Lane Hale, president of ECA Medical, a Thousand Oaks, Calif.-based designer and manufacturer of single-use instrumentation and surgery-ready procedural kits. “The advent of new types of plastics also helps lower costs while providing the robustness of metal, creating very strong instruments that meet the most demanding loads and stresses.”
Making an Instrument
Instruments, whether single-use or reusable, are often complicated to design and manufacture. They can be complex assemblies that utilize a range of materials and involve multiple processes, including precision machining, injection molding, welding, cleanroom assembly, testing, packaging, and sterilization.
Often a device is used in combination with two or three other instruments at the same time, making it imperative they work together with the utmost precision. This typically requires machining tolerances that are tighter than tolerances for products. “With spinal surgeries for example, a ratcheting screwdriver’s handle will come with a quick connector to lock onto various surgical instruments,” said Poulos. “The ratcheting screwdriver handle must offer very precise driving performance and, at the same time, retain the various modular instruments it attaches to. This creates the need for the two devices to fit together seamlessly, without any unintended movement or play. We design our ratchets and our quick connectors to be very precise to help surgeons perform surgeries better and safer.”
Reusable orthopedic instruments are some of the most complicated devices in the medical world. They can have many components, complex assemblies, and moving parts. For example, a retractor can have 70 components or more. All these different parts must work perfectly together. The design complexity of reusable instruments is not, however, the biggest challenge for CMs—instead, it is how to manufacture them efficiently, when their volumes are limited. OEMs place big orders when first launching a new reusable product; subsequent orders get smaller and smaller because the instruments stay in use. On the other hand, disposable instruments and implants are consumable, so there is a larger return on the investment (ROI) for CMs for these products.
“While it can make sense to purchase specialized machines and gauges when a steady stream of orders is expected, there may not be an ROI to do so for a reusable instrument order,” said Sible. “To keep costs down for the OEM, the supplier might need to rely on fixtures and equipment that can be used for a variety of products. The final product is the same, but the path for getting there is more difficult.”
New Technologies
CNC machines continue to improve, with more axes that allow the machining of complex components in a single setup, with easier user interfaces. Micromachining with femtosecond lasers—especially for creating tiny, complex parts and surface textures—is often the only way to make some of these parts and products. Robots on the manufacturing floor are now becoming so easy to use that they do not require engineers or dedicated technicians to program them. Collaborative cobots can now work safely in the presence of human workers.
Tegra Medical, for example, is using cobots in its factories to perform some of the most repetitive tasks efficiently and consistently. The robots have built-in sensor/optical safety systems that make them automatically stop operating if they encounter objects or people in their workspace. “This enables our workers and robots to work side by side, creating a collaborative work relationship between the robot and operator,” said Sible.
Advanced materials have a key role to play in the design of next-generation surgical instruments. OEMs have greater expectations of their raw material suppliers for top material quality, reliability, and performance—especially durability, hardness, and strength.
Reusable orthopedic surgical instruments must withstand harsh environmental conditions during cleaning and reprocessing. In addition, these devices manipulate bone and have extreme forces imposed on them during use. These factors require them to be made from robust materials that can handle these kinds of physical, thermal, and chemical stresses throughout their expected useful life. “This robustness often translates into harder materials that can be challenging to machine,” said Eric Walker, senior technical sales engineer for MedTorque, a Kenosha, Wis.-based manufacturer of instruments and implants for orthopedic and spine surgery. “This is especially true when tight tolerances or unique features are required.”
For example, 455/465 stainless steel is used for many components, including driver shafts and taps. Although it is strong and durable, it can be difficult to machine, especially for long shafts. It also has a shrinkage factor after heat treatment that needs to be considered before machining. 17-4 bar hardened stainless steel is another common steel that is challenging to process.
As an alternative, Carpenter Technology Corporation, a Philadelphia, Pa.-based provider of specialty alloy-based materials and process solutions for the medical device market, has developed a 17-4 bar product with significantly reduced residual stresses, which can sometimes cause out of tolerance instruments. “As a drop-in replacement for existing 17-4 products, this low-stress bar feedstock will increase machine throughput and decrease non-conforming instruments,” said Gaurav Lalwani, applications development engineer for Carpenter Technology. “The reduced residual stresses in the product translate to better machining performance and can help reduce the high scrap rate of 25 to 50 percent that often occurs when using the conventional 17-4 product.”
New coating materials that enhance the performance of surgical instruments continue to come into the market. For example, Picosun Group, a supplier of atomic layer deposition (ALD) thin-film coating solutions, is working with Chinese hospitals to test its ALD technologies as a way to create safer surgical procedures.2 Electrosurgical equipment uses high temperatures to cut and separate tissue, simultaneously coagulating blood. Tissue and blood sticking and burning on the blade during surgery can increase bleeding, tissue damage, tearing, and scarring. Picosun’s ALD technology can be applied as ultra-thin, pinhole-free coatings over an anti-adhesive micropatterning of the surgical blade, preventing blood and tissue from sticking to the blade.
Although the main focus for additive manufacturing (AM) has been orthopedic implants, there is increased interest from OEMs and CMs in printing patient-specific, custom surgical instrumentation. “For instance, a 3D-printed, patient-specific custom surgical guide can be highly advantageous in navigating a complex surgery,” said Lalwani. “For such applications, the choice of materials goes beyond regular titanium grades into alloys such as 17-4 PH, Custom 465, and other stainless material systems that our additive division produces in powders routinely used in the production of surgical instruments.”
3DEO, a Torrance, Calif.-based technology company, invented a patented metal 3D printer specifically for high-volume serial production. The process uses CNC machining on a layer-by-layer basis. The printer spreads a layer, then uses CNC to cut the perimeter of the part and any internal features, and then repeats the process by spreading another layer. 3DEO’s process achieves the design freedom of additive manufacturing because it builds parts on a layer by layer basis—yet it also achieves the precision and repeatability of CNC machining because that process is used to define the parts in the layer. The “green” printed parts are then sintered to full density in a furnace. The technology is ideally suited for small and complex metal components for surgical instruments and medical devices. For example, the company recently worked with an OEM to improve the design on a small, complex part used in a “bone scraper” instrument in 17-4 PH stainless steel. This product was not a direct replacement to their existing part, but rather a more complex design that could only be made with 3D printing. “The design is not achievable with traditional manufacturing methods,” stated 3DEO president Matt Sand. “The previous design was expensive to make with CNC machining—with 3D printing, we were able to optimize the design and reduce the cost by 50 percent compared to direct metal laser sintering, with no tooling costs.”
One of the most vexing issues for many MDMs is the maintenance and service life of mechanical torque limiting devices. Some have a comprehensive system to manage the usage of their devices and can return them to the manufacturer for recalibration on a routine schedule. Other OEMs prefer to simply dispose of the devices as service life is nearing the end. The FDA has been resolute in its efforts to monitor and ensure OEMs are adhering to some type of effective plan.
Gauthier Biomedical recently received 510(k) clearance for the IntelliTORQ, a patented electronic torque device that requires no recalibration or maintenance. It uses a Bluetooth-equipped electronic torque sensor to link to the cloud, navigation equipment, or a tablet. “This sterile, single-use device has a tolerance of ±5 percent and can store real-time data, as well as provide real-time feedback for the surgeon,” said Poulos.
Finding a Balance
OEMs and their CMs continue to search for ways that balance quality, technology, speed, and cost. These include searching for materials that provide better strength and corrosion resistance. For example, Carpenter Technology is developing several new materials, including high-nitrogen versions of 400 series stainless products and enhanced chemistry versions of the PH stainless family (17-4, Custom 455/465). “We also have been exploring new material solutions around the cutting instrument space,” said Lalwani. “Our newest material development, A-21, is an advanced carburizing and nitriding stainless steel that exhibits stainless behavior after carburizing, with high case hardness and deep case depth, making it suitable for knife blade and cutting tool applications.”
Depending upon the manufacturing processes being used, dimensioning schemes and tolerances can significantly drive part cost without effectively contributing to the overall device function. In-process quality requirements and unique/special processing methods can reduce throughput, add labor costs, and potentially increase scrap. “By identifying these issues and limitations to the OEM early, it is quite possible to achieve an improved product design that captures all of the design input requirements, in a more cost-effective manner,” said Leibel.
The challenge for many manufacturers is not so much meeting validations—they have had many years to hone these skills. Instead, the challenge is getting OEMs to recognize the value in improving a process, and approving the extra investment or cost. When the CM sees an opportunity to improve a process, especially for a product it has been manufacturing for years, the customer is often reluctant to change anything about the process because of the up-front costs. “For example, if you’re making a 10-year-old product, chances are there are newer, better machines to make it on,” said Sible. “But you’re locked into the original process. Any change, even to a better machine, would require another set of validations, which can be more cost than the customer can justify.”
Many OEMs have expectations for cost downs over the life of a product, noted Leibel. These are typically absorbed by the supplier through continuous improvement efforts. When a change can result in a direct cost reduction to the OEM, the activity often gains momentum and gets managed through the supplier’s change notification process. However, there are often changes a manufacturer can make that do not necessarily result in a direct cost reduction for the OEM, but instead improve product quality, employee safety, delivery metrics, and more. “When these activities do not have a direct path to cost reduction, it can be difficult for OEMs to support the changes through their quality systems,” said Leibel. “OEMs need to appreciate the impact they can have on their contract manufacturers when they are unable to implement potential continuous improvement efforts, either based on available resources or low priority.”
Sible agreed.
“An OEM’s expertise is in design, not manufacturing, so it may not occur to the engineers that something can be made more efficiently in an unexpected way,” said Sible. “They don’t always understand that combining different technologies can be more efficient than using just one.”
For example, Tegra Medical makes an assembly for an orthopedic instrument that requires 78 steps, including cutting the blanks, cleaning, and grinding. “The OEM might think it is impossible to make it efficiently with so many steps, but the reality is that doing it this way lets us make the product in high volume for less than it would be to machine it from a solid block. This is why it is so critical to involve trusted suppliers early in the DFM process.”
References
Mark Crawford is a full-time freelance business and marketing/communications writer based in Madison, Wis. His clients range from startups to global manufacturing leaders. He also writes a variety of feature articles for regional and national publications and is the author of five books.