A Matter-of-Fact Discussion of Orthopedic Device Materials

Orthopedic device innovation is being transformed by rapid advances in biomaterials, manufacturing technologies, and patient-specific design. Healthcare systems are demanding longer-lasting implants, quicker recovery times, and improved clinical outcomes, so material selection has become a main driver of product development across joint reconstruction, trauma fixation, spinal implants, and sports medicine.

Traditional metals like titanium and cobalt-chrome remain critical for their strength and durability. However, emerging materials like bioresorbable polymers, advanced ceramics, porous structures, and surface-engineered coatings are expanding the possibilities for performance and biocompatibility. Simultaneously, additive manufacturing is allowing creation of highly customized implants with optimized mechanical properties and enhanced osseointegration.

Sustainability, supply chain resilience, and regulatory expectations are also impacting how manufacturers assess their material choices. Over the past few weeks, ODT spoke to several experts in the industry to explore key materials trends shaping orthopedic devices, highlighting the technologies, clinical priorities, and market forces that are expected to define the next generation of orthopedic solutions.

• Natalie Dragunat, global marketing manager, Healthcare, Syensqo
• Thomas Guéguen, GM of Forecreu America Inc., U.S. subsidiary of Forecreu SAS
• Dennis Rahill, business development manager, United Performance Metals
• Corey Seacrist, manager, sales & marketing, Poly-Med
• Jeff Smith, global head of medical device solutions, Evonik Health Care
• Onno Visser, managing director, CaP Biomaterials
• Dr. Richard White, principal consultant, Lucideon

Sam Brusco: What factors most strongly influence material selection for orthopedic devices?

Natalie Dragunat: The material must meet biocompatibility standards for implantable materials, typically ISO 10993, which outlines key testing methods for materials used in permanent implants. Rigorous testing helps confirm suitability for implantation.

Orthopedic devices must withstand repetitive loads and stresses over long periods without failing or deforming. High fatigue and creep resistance are essential for long-term performance.

Materials with an elastic modulus similar to bone help distribute loads more naturally, minimizing stress shielding, or bone loss caused by a mismatch in stiffness. Radiolucent materials allow for clearer post-operative imaging (X-ray, CT, MRI), which is important for monitoring healing and device placement.

Materials must remain stable in the body and resistant to corrosion over time, ensuring long-term safety and efficacy. The ability to mold complex shapes and integrate features can improve device performance and surgical outcomes. Other considerations include low thermal and electrical conductivity (for advanced implants with integrated electronics) and lightweight properties for patient comfort.

Thomas Guéguen: Material selection is mainly application driven. For implants, fatigue performance and long-term reliability are critical, while for instruments and rotating tools, torque resistance, hardness and machinability are key factors.

Besides mechanical properties and biocompatibility, we increasingly see design for manufacture and supply chain stability influencing material decisions. OEMs and CMOs are looking for materials that meet specification requirements and can be processed efficiently and sourced reliably.

Dennis Rahill: UPM doesn’t suggest any specific grades for implants and or instruments because of potential liability issues. We teach new supply chain people about some of the commonly used alloys for implants and instruments and refer them to common ASTM and AMS specifications. We take effort and pride in going in depth with these raw material specification and applications do so we can be assured they’re getting what they really need. If customers ask for specific technical requirements outside of the industry standards, we try to follow up with our supplier’s metallurgical staff to answer those kinds of questions.

Corey Seacrist: Typically, absorbable medical devices are designed based on multiple performance requirements that must be met for a period of time before the device loses function to a level that’s no longer able to meet clinical requirements. Mechanical requirements, including but not limited to modulus, strength, and fatigue, are critical performance criteria for most absorbable orthopedic medical devices. Additionally, absorbable biomaterials must have favorable biocompatibility characteristics or they pose significant patient risk throughout the degradation life of the material.

Jeff Smith: In orthopedics, material selection starts with choosing options that best match the characteristics of the target tissue, whether bone, tendon, or soft tissue. Strength and biocompatibility are core factors and can be tailored to the device’s needs. For bioresorbable devices, selecting a material with the right degradation profile is crucial. VESTAKEEP PEEK, meanwhile, remains a leading choice for long term implants due to its bone like properties and excellent biocompatibility.

Onno Visser: In the end, it’s the sum total of factors that must be balanced and quite often there are trade-offs that must be thoughtfully navigated. Comparing such iterations during the design phase allows for locking in the ideal set of specifications with confidence, and based on data. CaP Biomaterials’ ability to fine-tune bioceramics enable customers to design the optimum device. Beyond selecting the right calcium phosphate fine-tuning porosity, chemical composition, surface area, and particle size are some of the tools that come to mind.

Dr. Richard White: Material selection for orthopedic devices is driven by a combination of biological compatibility, mechanical performance, and application‑specific functional requirements. A key early consideration is the broad range of material classes involved—metals, polymers, ceramics, and composite materials—each with different processing routes, performance profiles, and compliance challenges.

Some requirements are common across almost all devices, regardless of material class. These include biocompatibility, control of extractables and leachables, and avoidance of toxic or undesirable elements. Beyond these baseline factors, material selection becomes highly application-specific.

In load‑bearing implants such as femoral components, mechanical strength, fatigue resistance, and fracture toughness are critical. In contrast, for wear couplets, such as femoral heads and acetabular liners, the interaction between materials, wear rate, and debris generation become dominant considerations. Other devices, such as bone void fillers or cements, place far greater emphasis on resorption behavior, biological response, and handling characteristics.

Brusco: How does the manufacturing process (casting, forging, machining, additive manufacturing) affect material properties?

Dragunat: Manufacturing process influences key material properties, including strength, fatigue resistance, surface characteristics, and dimensional stability. In orthopedics, process selection is guided by factors such as device design, modeling tools like mold flow analysis, and prototyping to help ensure those properties meet application demands.

Guéguen: Manufacturing processes have a direct impact on material performance, particularly through changes in microstructure, surface roughness, and residual stress—all of which are critical for fatigue behavior.

Processes like extrusion, rolling, and drawing can improve mechanical properties but require strong metallurgical control to ensure compliance with ASTM standards. This technology is offered at our France facility which is well suited for high-volume production and consistent performance.

In the U.S., we use a cold forming and precision drilling technology. It allows us to preserve the base material’s metallurgy while ensuring tight tolerances, which is important for certain applications like minimally invasive surgeries and high-precision applications like in robotics.

Seacrist: Most absorbable implants intended for use in hard tissues are manufactured via injection molding due to their strength and manufacturing scalability. 3D printing has recently been utilized for products intended for craniomaxillofacial (CMF) applications that include Osteopore’s polycaprolactone (PCL)/β-tricalcium phosphate (TCP) implants and Dimension Bio’s (previously Dimension Inx) CMFlex^TM Synthetic Bone Graft comprised of hydroxyapatite particles and polylactide-co-glycolide (PLGA) polymer. These 3D-printed implants allow bony ingrowth due to their lattice design, albeit at the expense of overall device strength compared to solid implants. Lactoprene HMX was designed to circumvent some of the challenges observed with typical lactide-based 3D printed implantable devices contemplated, with a significant increase in Young’s Modulus, facilitating a more robust lattice-based implant.

Smith: Selecting the right manufacturing process and the right polymer go hand in hand, as processing directly impacts a material’s physical and degradation behavior. Every material degrades over time, and with bioresorbables like RESOMER, processing conditions can be adjusted to achieve the desired mechanical performance and degradation rate. Our expertise lies in understanding how polymers respond to different manufacturing methods, ensuring consistent and predictable material performance.

Visser: The manufacturing process might have specific requirements that go beyond specifications of the final device. A good example is the flowability of powders, with a high degree of consistency in particle size distribution and morphology to allow you to consistently and predictably feed powder into compounding or spray-equipment.

Dr. White: Processes such as casting, forging, machining, and surface finishing are well understood in the industry and have long-established links between processing parameters and mechanical behavior.

More recently, additive manufacturing has gained traction, particularly where complex or patient‑specific geometries are required. While AM can offer significant design freedom, it’s not a simple, like‑for‑like replacement for traditional processes. The impact of additive manufacturing on microstructure, residual stress, and defect population can be substantial.

AM processes can introduce issues such as porosity, lack‑of‑fusion defects, and anisotropic behavior, resulting in non‑uniform properties that vary with build orientation, location within the part, and even from build to build. As a result, a far deeper understanding of both the material and the process is required to ensure reliable and repeatable performance.

Regardless of the manufacturing route, it’s essential the process is fully characterized, validated, and controlled, with material testing aligned to the final manufactured condition rather than assuming equivalence with specification values alone.

Brusco: What emerging materials show the most promise for orthopedic devices?

Dragunat: We offer Solviva biomaterials for implants. Eviva PSU and Veriva PPSU are ideal for non-load bearing implant applications, while Zeniva PEEK is well-suited for both load bearing and non-load bearing applications.

Zeniva PEEK is radiolucent for clear medical imaging (X-ray, CT, MRI) and has bone-like elasticity to reduce stress shielding. It’s corrosion-resistant and biocompatible, lightweight, and allows for complex, innovative implant designs. It’s available in variants such as carbon fiber-filled (for added strength) and barium sulfate-filled (for radiopacity).

Eviva PSU (Polysulfone) is available in ISO 10993-tested biocompatible grades and features excellent chemical resistance and toughness. It’s available in transparent and white grades for design flexibility and visualization. Veriva PPSU (Polyphenylsulfone) is also available in ISO 10993-tested biocompatible grades and boasts excellent chemical resistance and toughness.

Guéguen: Additive manufacturing continues to grow, ideal for complex geometries and porous structures for osseointegration. Magnesium-based materials seem to be gaining attention due to their bioresorbable properties and radiolucency compared to traditional metals, but adoption remains cautious. We also see increasing interest in hybrid solutions where additive manufacturing or advanced materials are combined with conventional processes to improve performance and manufacturability.

Rahill: Additive manufacturing for typical orthopedic implants has started to take off and become commercialized over the past five to six years. New additive implants can be more biocompatible because of better osseointegration and ability to offer custom sizing to the patient’s anatomy. These newer additive hip, knee, and shoulder implants are designed so well that it leads to much fewer revision surgeries, and long-term quality of life for patients.

Seacrist: We recently launched Lactoprene HMX as a solution to challenges observed with typical PLLA, PLGA, and PDLLA-based orthopedic implants. Notably, Lactoprene HMX exhibits superior Young’s Modulus and creep performance compared to amorphous PLLA, PLGA, and PDLLA-based materials. These differences in mechanical properties resulted in a 50% decrease in torque insertion for Lactoprene HMX bone screws compared to these traditional materials, which is anticipated to result in decreased risk of thread deformation.

Smith: There is growing potential in combining proven synthetic polymers with additives, some of them entirely novel, to unlock new capabilities. By understanding how to incorporate additives at the right stage, we can influence not only device characteristics but also how materials process into semi-finished forms. This enables customers to fine-tune attributes such as adhesion or processability to achieve the specific performance needed.

Visser: As a contract manufacturer, we cater to companies that have diverse ideas on how to answer this question and we’re here to work with their R&D teams. Our know-how lies in manufacturing, optimizing pore structures at both the micro and nano scales for instance, allowing our customers to optimize biological performance. Our customers look to optimizing handling to make sure the surgeon can perform his surgery with complete control. We’ve seen an increase in demand for calcium sulfate, so we recently decided to introduce that to our product portfolio.

Dr. White: Rather than a single “breakthrough” material, much of the current progress in orthopedics is coming from incremental innovation and hybrid material systems. This includes improved metallic alloys with tailored microstructures, advanced polymers with enhanced wear and oxidative stability, and ceramics engineered for improved toughness and reliability.

There’s growing interest in surface‑engineered solutions, such as bioactive or wear‑resistant coatings, which allow established bulk materials to be optimized for specific biological or tribological functions without introducing entirely new material systems. Similarly, composite and functionally graded materials offer opportunities to better match mechanical properties to those of natural bone, potentially reducing issues such as stress shielding.

Bio‑resorbable metals, advanced calcium phosphate systems, and additive‑manufactured lattice structures designed to encourage osseointegration are also areas of active development. In all cases, the most promising materials are those that can demonstrate not only technical performance, but also manufacturability, consistency, and regulatory viability.

Brusco: How difficult is it to introduce novel materials into regulated medical devices?

Dragunat: Introducing novel materials into regulated medical devices can be challenging, as they often require more extensive testing, risk assessment, and validation to demonstrate safety and performance. While resource-intensive, that process is essential to support regulatory acceptance and patient safety.

Guéguen: Introducing new materials is challenging due to regulatory constraints and difficult validation requirements, so the industry tends to rely on established grades. This makes standardized, readily available solutions valuable. 

Rahill: Extremely, as the FDA has really been cracking down on all the players to make sure all the new products are very safe for patients.

Seacrist: Absorbable biomaterials pose a high risk of biocompatibility issues due to all components of the material degrading and absorbing into the body. The FDA requires implantable medical devices to be evaluated through an ISO 10993 testing panel. Additionally, absorbable and implantable medical device biocompatibility is highly dependent on processing parameters used to manufacture the product. Because most absorbable and implantable medical devices are tested for biocompatibility using a per-product line approach, with limitations based on how the manufacturer of record designs their test panel.

Smith: Introducing a completely new material into a regulated device is challenging, costly, and time-consuming. A more efficient alternative is building on existing, well characterized materials—such as Evonik’s RESOMER bioresorbable polymers—and adding new features or functionalities. This approach often supports a 510(k) pathway, reducing risk and regulatory burden because only the new feature must be justified, rather than the entire material.

Visser: Companies that have identified regulatory affairs as a core competence from the start are very well prepared to help the FDA understand how a new material provides clinical utility while also being safe. Involving the regulator from the get-go to ensure potential questions are identified early helps building robust data that ticks all the boxes later on. If you develop new materials for the right reason (better clinical outcomes) and you take a solid approach you might find even though it’s not easy, cheap, or fast, it’s also not impossible to get regulatory approvals. This is also just a starting point, as you’ll need to convince the market of your convictions (and data).

Dr. White: Introducing novel materials into regulated medical devices is inherently complex and places a significant evidential burden on manufacturers. In addition to demonstrating a device performs its intended clinical function, manufacturers must provide robust data to build regulatory confidence in the material, the manufacturing route, and the long‑term safety of the device.

This process typically involves a combination of mechanical testing, chemical characterization, in‑vitro studies and, where required, in‑vivo evaluation. The depth and breadth of evidence needed varies by device type, jurisdiction and—critically—the degree of novelty involved.

The more novel the material or processing route, the greater the level of scrutiny and supporting data required. As a result, many manufacturers choose to innovate within established material families or standards frameworks, balancing innovation with regulatory risk and time‑to‑market considerations.

Brusco: What ASTM or ISO standards are most important for orthopedic device materials?

Dragunat: Some of the most relevant standards for orthopedic device materials include the ISO 10993 series for biocompatibility and biological risk evaluation, as well as material-specific standards such as ASTM F2026 for PEEK and ASTM F648 or ISO 5834 for UHMWPE. For joint replacement applications, wear and durability standards such as ISO 14242 and ISO 14243 may also be important.

Guéguen: ASTM standards such as F136, F138, and F899 are references for orthopedic materials, but compliance can go beyond material specs. Strong quality systems and full traceability are essential—ISO 13485 is a key requirement for medical device manufacturers and suppliers that ensures robust quality processes, traceability, and regulatory compliance.

All of our facilities are ISO 13485 certified. Our French facility is also FDA registered and ISO 14001 certified, reflecting our commitment to environmental responsibility. In the U.S., our facility is also certified to ISO 9001/13485 and AS9100D, and is ITAR compliant, supporting both medical and aerospace/defense industries.

Rahill: ISO 13485 is the standard for medical, and the most common and widely used raw material specification is ASTM F136 for the vast majority of implants.

Seacrist: All absorbable medical devices must meet the biocompatibility requirements outlined in ISO 10993, with additional requirements compared to non-absorbable permanent devices. ISO 10093-6 states all devices must be tested in a preclinical model minimally at an early time point where degradation isn’t taking place, a mid-time point when degradation is taking place, and a late-time point when the implant has been essentially absorbed. Essentially absorbed is defined as a time interval observed when minimal amounts of absorbable component remain at the implant site. In the absence of complete absorption, the affected tissue’s response, structure, and function must have reached steady-state, or if the absorbable material/degradation products are in a state of limited visually-identifiable presence via histological analysis.

Device manufacturers may also utilize ASTM F1635 to evaluate device performance in vitro before performing more costly and timely preclinical animal studies required for 510(k) clearance. ASTM F1635 is the primary standard for evaluating the in vitro degradation of hydrolytically degradable polymers for surgical implants. Device designers will typically measure mass loss, molecular weight changes, and mechanical properties throughout the implant lifetime simulated by being placed in a solution buffered to pH 7.4 and temperature of 37 °C. Here, the mechanical properties measured are ideally tailored to the performance requirements for the device in question.

Smith: ISO 13485 standards are essential for supplying materials into regulated medical device markets. Evonik provides the data and documentation customers need to support their regulatory submissions. Our biomaterials have a long history of use in approved devices, giving customers confidence in their regulatory acceptance and clinical standards.

Visser: Standards like ASTM F1185 (Hydroxyapatite), ASTM F1088 (Beta-TCP), and ASTM F2224 (Calcium Sulfate) guide material composition. ISO 13175-3 and the ISO 13779 series cover calcium phosphate, hydroxyapatite, and ceramic-based substitutes, ASTM F1926 (Dissolution) is another standard that comes to mind.

Dr. White: Orthopedic devices sit in a wide and complex standards landscape, with relevant documents found across both ISO and ASTM frameworks. Many standards are material‑specific, covering the chemical composition and mechanical requirements of commonly used metallic alloys, polymers, and ceramics.

Other standards focus on test methodologies and performance assessment, such as wear testing of articulated joint surfaces or the characterization of calcium phosphate and hydroxyapatite coatings. Given the diversity of orthopedic devices, relatively few standards apply universally across all applications.

One key overarching standard is ISO 14630:2024—Non‑active surgical implants—General requirements, which provides high‑level requirements applicable across a broad range of implantable devices. In practice, compliance typically involves a combination of general requirements supplemented by material‑, process‑, and application‑specific standards.