The Emergence of Fiberglass Foot Technology

Written by Bryan Potok, CPO on June 11, 2018
Last updated on May 18, 2019

Prosthetic feet have evolved in terms of aesthetics and increased functionality over the past several years. Prosthetic feet are now available in a wider range of materials and styles that can handle the most extreme activities. Your choice of material largely depends on your lifestyle and occupational needs.

Fiberglass is a new innovative material in prosthetic foot design that offers increased flexibility and durability. In fact, you can expect close to zero dead spots from fiberglass feet. Fiberglass really shines if you squat heavy weight in the gym, in part due to its larger flex window. Carbon fiber, on the other hand has a smaller flex window, meaning your carbon foot will not show signs of stress before failing.

Fiberglass provides additional rotational torsion that reduces the impact on your knees, back, and hip. This is why extreme prosthetic users who want to make a switch from carbon graphite will find fiberglass feet as their material of choice.

Fiberglass Vs. Carbon

Fiberglass is made up of melted glass extruded through bushings, which results in a string-like material. This string is woven into yarn then into cloth. Although the cloth can be molded and bonded into various shapes similar to carbon fiber, fiberglass requires much less heat and pressure to complete the bond between each layer.

Strength and Durability

Between the two, carbon fiber outperforms fiberglass in its tensile strength or the amount of force required to pull the fiber apart, as well as in compressive strength or the amount of force pressing down on a fiber. But in the weight department, both materials are relatively similar.

Mode of Failure

While carbon fiber may be stronger than fiberglass, the latter is much more durable since you can bring it close to its breaking point several times without much cause for concern. The same can't be said about carbon fiber, though.

Pushing carbon fiber to its limits can result in catastrophic failure. It's highly likely to delaminate and fracture, which is never a good situation. With fiberglass, however, deformities or stress areas will develop first before it completely breaks. Its excellent fatigue resistance and structural features prevent catastrophic material failure. So, this should ease your mind when you're going heavy on leg day--or any high activity sport.

Cost

Budget-wise, fiberglass is more economical. It's more difficult and pricier to manufacture carbon fiber, as compared with fiberglass. This is why carbon fiber comes with a slightly heftier price tag.

Aesthetics

A lot of people opt for the space age and futuristic look of a shiny black carbon foot?

What's New With Fiberglass Feet

Maverick Xtreme AT

The Maverick Xtreme AT offers a higher level of flexibility and durability while supporting energy return and storage. Its breakthrough fiberglass foot keel and heel design is lightweight and sturdy enough for use on all terrains with its ±16° inversion and eversion.

Among the other features of the Maverick Xtreme include:

Waterproof
Split keel for increased ground compliance
Sandal toe and regular option
Wave heel plate design for better energy return and storage
Natural feel during strenuous exercises and daily activities

The Maverick Xtreme AT fiberglass foot comes with a split keel design for ground compliance and stability on uneven terrains.

RUSH ROGUE

Featuring a unique design, the Rush Rogue Foot offers a dynamic and comfortable ankle and foot motion. It's all about the newer fiberglass composite material called Flexeon that provides more flexibility than a traditional prosthetic foot. There's zero dead spot and excellent energy return. With its Vertical Loading Pylon, you'll experience greater impact absorption when stepping off a curb.

Additional prosthetic features are the following:

Smooth roll-over
Natural ankle movement
Incredible reliability

Rush Rogue Foot offers a dynamic and comfortable ankle and foot motion with this fiberglass technology

Final Word

Fiberglass feet offer more ease and comfort with every stride regardless of how intense the activity may be. With each design iteration of fiberglass foot, such as with the entry of Freedom Innovations, this material is starting to competitive options to carbon prosthetic feet. And let's not forget the near indestructibility of fiberglass, which offers greater advantages to extreme prosthetic users engaged in high demanding activities.

Are you wearing a fiberglass foot, share your experience by adding a comment below.