3D Printed Prosthetics: What They Are and How They Work

Nearly 2.3 million people in the United States are living with limb loss, and 3.4 million live with limb differences. Traditional prosthetics can be expensive and time-consuming to produce, putting them out of reach for many who need them. Enter 3D-printed prosthetics—a transformative medical application of 3D printing technology that’s redefining accessibility and affordability in the medical field.

3D printing enables the creation of highly customized prosthetics that fit individual needs, often at a fraction of the time and cost required by conventional methods. In this article, we’ll explore what 3D-printed prosthetics are, how they’re designed and manufactured, and why they’re becoming a game-changer for millions of people worldwide.

What is 3D Printing For Prosthetics?

3D printing for prosthetics refers to the use of 3D printing technology to design and produce artificial body parts. Prosthetics are used when a person has lost a body part because of an accident or congenital defects. In some cases, patients may need to undergo amputation surgery before they can use prosthetics. 

What’s the difference between 3D-printed prosthetics and traditional prosthetics?

3D printing prosthetics is more affordable than traditional manufacturing methods and offers greater customization and faster speeds. 

• Customization: Computer-Aided Design (CAD) software allows designers to produce prosthetics according to the user’s exact body measurements and unique anatomical requirements. Customizing prosthetics using traditional methods is possible, but it’s generally more complex because it involves manual adjustments and specialized fittings.
• Cost: Lower material costs and streamlined production make 3D printing more affordable. This makes 3D-printed prosthetics accessible, especially in low-income areas or for growing children who need frequent replacements.
• Speed: Unlike traditional manufacturing processes that require molding, casting, and assembly, 3D-printed prosthetics can be produced in a single print run. This means you can deliver prosthetics to patients in a few hours or days.
• Weight: 3D-printed prosthetics are lighter because they can be designed with internal lattice structures that reduce material usage without compromising strength. Traditional prosthetics made from heavier materials like metals or dense plastics place more strain on the user, especially for extended wear.

Types of 3D-Printed Prosthetics

There are various 3D printed prosthetics that cater to different amputation levels. Each has its unique design and functional considerations. 

Transradial: 3D Printed Prosthetic from Elbow to Hands

Transradial prosthetics are used to replace the forearm and hand for people who require amputation below the elbow. It typically includes a 3D-printed socket that fits snugly around the residual limb, a forearm section, and a hand with fingers. Fingers may be static or have functional capabilities.

It’s possible to design transradial prosthetics that can grasp and hold objects with simple mechanical systems or advanced electronics. Sensors are often used to detect muscle movements (myoelectric technology), which allows the patient to control hand movements with muscle contractions.

Transhumeral: 3D-Printed Prosthetic from Shoulder to Hands

Transhumeral prosthetics are a bit more complex because they need functionalities of both elbow and hand. They’re also large—they replace the entire arm and typically include a shoulder attachment, upper arm section, elbow joint, forearm, and hand.

3D printing helps produce lightweight transhumeral prosthetics compared to traditional methods. It also offers greater design freedom, enabling you to integrate powered joints and moving components while remaining adaptable to a patient’s shoulder and arm shapes.

Transtibial: 3D Printed Prosthetic from Knee to Foot

Transtibial prosthetics replace the lower leg, including the shin and foot, for people with an amputation below the knee. The design includes three 3D-printed components: a socket for the knee region, a pylon (the central supporting structure), and a foot.

The pylon and leg are designed to mimic a natural leg’s function, including shock absorption and providing stability during walking. Moreover, the socket must fit the residual limb snugly for optimal comfort and functionality.

3D-printed designs can incorporate shock-absorbing materials that offer users greater comfort and stability. 3D printing also allows for precise digital scanning and custom-fitting to match the exact shape of a user’s residual limb.

Transfemoral: 3D Printed Prosthetic from Hip to Foot

Transfemoral prosthetics replace the entire leg, including the thigh, knee, lower leg, and foot. The knee joint is the most critical part of a transfemoral prosthetic and may be mechanically or electronically controlled to support stability and movement. Some designs use microprocessors to adjust the knee’s angle to enable it to adapt to different terrains or movement speeds.

3D printing helps you achieve a close fit to the user’s upper leg shape that allows precise, lightweight designs without spending time on labor-intensive and time-consuming adjustments.

Materials such as laminated carbon fiber or thermoplastics that are commonly used in traditional methods have shaping and flexibility limitations. 3D printing helps achieve the right strength and comfort by combining materials with different properties.

Materials Used To 3D Print Prosthetics

The material choice greatly influences the strength and weight of the prosthetic. Choosing an appropriate material based on your design needs and the type of prosthetic you want to produce is mission-critical. 

Here are some popular material choices for 3D-printed prosthetics:

• HP PA-12 White: Using PA-12 White comes with various benefits. It’s a durable nylon powder with a low moisture absorption rate and offers high impact resistance and a smooth surface finish. If you’re looking to 3D print parts that need to withstand frequent movement and resist wear while remaining lightweight and comfortable on the skin, PA-12 is the perfect choice. HP PA-12 is our top choice because it offers:
  • High dimensional accuracy: This ensures precise fitting, which is critical for custom prosthetic designs.
  • High flexibility and durability: PA-12 has a high tensile strength and elongation at break, which make it ideal for wear-resistant components that ensure repeated use.
  • Up to 80% surplus powder reusability: This makes PA-12 eco-friendly, helping you reduce waste while maintaining consistent performance across production cycles.
  • Compatibility with HP’s Jet Fusion technology: PA-12’s compatibility with Jet Fusion technology allows for faster production times compared to traditional methods.

• Nylon: Nylon offers a good balance between strength and comfort. It helps produce durable and lightweight prosthetics that can handle impact and movement and cracking or weakening down.
• Carbon fiber: Carbon fiber is extremely strong yet lightweight, making it ideal for load-bearing prosthetics. The high strength-to-weight ratio also reduces fatigue for users, making it especially useful in lower-limb prosthetics.
• Aluminum: Aluminum is lightweight and corrosion-resistant and commonly used to join or connect parts in prosthetics. It offers strength without adding excess weight, both of which are critical for mobility and comfort.
• Epoxy resin: Epoxy resin is an ideal choice for casting and reinforcing parts. It’s durable, customizable, and offers a smooth finish that improves user comfort and can be shaped to fit snugly.
• Foam: Foam is used for liners or padding within prosthetic sockets to add a cushioning layer that reduces pressure points and prevents skin irritation.

How To 3D Print Prosthetics

Here’s an overview of the process for 3D printing prosthetics and a few design considerations you should consider.

1. Scanning the Limb

A precise scan of the patient’s residual limb is critical to creating a custom, well-fitted prosthetic. High-resolution scanning techniques like structured light scanning and laser scanning are your best bet—they accurately capture the limb’s dimensions, contours, and unique anatomical variations.MRI or CT scans are used when you need internal details in cases where residual limb anatomy is complex or there are post-surgical modifications. The output of the MRI or CT scan is converted into a digital mesh format, such as Standard Tessellation Language (STL) or Wavefront Object (OBJ), to ensure minimum loss of detail.

2. Digital Modeling of Prosthetic

Once you have an accurate scan, use CAD software to build a detailed model of the prosthetic. Here’s what digital modeling involves:

• Socket design: Shape the socket to evenly distribute weight and minimize pressure points based on the anatomical scan. This ensures maximum comfort and stability. Use modeling techniques like adaptive meshing and parametric modeling to further customize the prosthetic according to unique patient contours.
• Component integration: The next step is to integrate additional components, such as jointed sections, mounting points, or functional parts, into your design. Make sure you choose a material with the right properties based on performance requirements and anticipated load conditions.
• Simulation and stress analysis: Most advanced CAD programs include FEA (Finite Element Analysis) capabilities. Use FEA to simulate real-world stresses and strains on prosthetics and see how they perform under various conditions. Adjust dimensions and reinforcement areas to optimize durability and flexibility as needed.

3. Printing the Prosthetic

Now that your model is finalized, you need to choose a 3D printing technology and material. The choice depends on your functional and structural requirements.

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Here’s an overview of the printing process and some general guidelines to help you make the right choices:

• Material selection: Most common choices include HP PA-12 for its material properties—high impact resistance, carbon fiber-reinforced nylon for lightweight strength, and thermoplastic elastomers (TPEs) for flexibility in socket liners. In addition to the strength-to-weight ratio, consider the material’s biocompatibility and post-processing requirements.
• Printing technology selection: Selective Laser Sintering (SLS) and Multi Jet Fusion (MJF) are the most common choices for high-strength components that require precise geometries. For prosthetics where strength and aesthetics are both critical, Fused Deposition Modeling (FDM) with advanced filaments (such as carbon fiber-infused polymers) is more suitable.
• Build orientation and support structures: 3D-printed objects are usually weaker along the layer boundaries, and that’s why orientation is generally set so that primary stress lines align with layer bonds. When printing prosthetics, orient the print along anticipated load directions (for example, this could be the axis of a limb) to improve durability, especially in load-bearing areas like sockets or joints. Similarly, support structures like lattice supports are used when producing overhanging or bridging parts (for example, the concave surface inside a socket or intricate joint structures) to balance print stability.
• Post-processing: Post-processing with methods like sanding or chemical smoothing helps ensure functionality and aesthetics. For high-stress components, consider heat treatments or resin coatings that improve strength.

4. Prosthetic Fitting

The printed prosthetic then undergoes a fitting session. Dynamic testing of the part’s attachment points and articulations in response to patient movements helps identify any need for modifications. When modifications are necessary, a 3D scan and rapid reprinting are used to achieve precise, on-the-spot adjustments.

Sensor calibration and electronic tuning are also important for active or myoelectric prosthetics to ensure optimal response. Customize and fine-tune soft liners or adaptive inserts to prevent skin friction or pressure points.

More to Know About 3D Printed Prosthetics

Let’s now address some common questions about 3D-printed prosthetics.

What is the best material for 3D-printed prosthetics?

HP PA-12 White is the best material for 3D-printed prosthetics because it offers:

• Superior mechanical properties (such as exceptional impact resistance and flexibility)
• High dimensional accuracy
• Best-in-class isotropy
• Outstanding reusability or surplus powder
• Consistent white finish for aesthetic customization

What is the lifespan of a 3D-printed prosthetic?

The lifespan of a 3D-printed prosthetic varies based on the material used, the user’s activity level, environmental exposure, and specific design features. However, they typically last anywhere from six months to three years or more.

How much does a 3D-printed prosthetic cost?

The cost of a 3D-printed prosthetic varies based on the type, material used, and level of customization required. For example, a basic 3D-printed prosthetic limb (such as a hand or lower leg prosthetic) ranges between $50 and $500.

Prosthetics made with PLA or ABS are cheaper, while prosthetics made using medical-grade nylon or carbon fiber composites are more expensive. Transfemoral and transhumeral prosthetics are generally more expensive because they’re highly customized and require intricate fitting.

Is 3D printing good for prosthetics?

3D printing is highly effective for prosthetics because it offers design freedom and rapid production. With 3D printing, you can use lightweight yet strong materials and produce components at a fraction of the cost of conventional manufacturing methods.

How long does it take to make a 3D-printed prosthetic?

It typically takes between several hours and a few days to make a 3D-printed prosthetic. The exact time depends on the prosthetic’s complexity, size, and post-processing requirements.

3D Print Your Prosthetic with UPTIVE Advanced Manufacturing

3D printing prosthetics is an excellent option when you need to make prosthetics with complex shapes quickly and at a low cost. The two most critical ingredients to manufacturing high-quality prosthetics are working with the right manufacturing partner and selecting the right material.

HP PA-12 White is an excellent choice in most cases because of its outstanding material properties and high reusability of surplus powder. Its durability and flexibility make it suitable for functional, load-bearing prosthetic parts. At the same time, dimensional accuracy allows you to manufacture custom, well-fitted prosthetics that can maintain structural integrity over time.

Where can you access this material, and how can you ensure your prosthetics meet the highest standards? UPTIVE Advanced Manufacturing is your trusted partner in producing 3D-printed prosthetics with precision and care. Whether you need diagnostic equipment, prosthetics, dental implants, or surgical instruments, UPTIVE has the expertise to deliver customized, high-quality solutions tailored to your needs.

With state-of-the-art 3D printing technology and materials like HP PA-12 White, UPTIVE ensures your prosthetics are durable, accurate, and ready to perform. No matter the application, every project requires a specific solution, and we’re focused on helping you select the ideal material and manufacturing technology to take your idea from concept to completion.

Contact UPTIVE today to learn how they can support your prosthetic manufacturing journey with innovative solutions and unparalleled service.