Embracing New and Advanced Materials

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For technicians, using advanced material in O&P makes way for lighter, more durable devices.

A socket fabricated with polytol resin. Photographs courtesy of Otto Bock HealthCare
A socket fabricated with polytol resin. Photographs courtesy of Otto Bock HealthCare

The O&P profession has come a long way from the days of leather and iron. Today, the materials used to fabricate an orthosis or prosthesis are lighter, more durable, and ultimately more comfortable for the patient. As technicians weigh their options and consider using some of the newer and more "advanced" materials in orthotic and prosthetic design, they need only open their minds to a material's possibilities.

Advanced materials such as prepreg, urethane, and polytol resin are changing how technicians create devices for their patients. However, Tony Wickman, RTPO, owner of Freedom Fabrication, Havana, Florida, warns, "In keeping with the logical application of a material, it is easy to figure it as a panacea, but whatever we do must be for the benefit of the patient.

"The vast majority of what we do comes from the filtering down of old ideas," he adds. "We create devices a certain way with certain materials because that is the way we were taught to do it. We must question everything we do and let common sense guide us to look for new solutions while focusing on how best to fix the patient's problem without creating a new one."

Branching Out

In striving to help patients, it is easy to only think about what materials are readily available and what material you are most comfortable working with. Sometimes, however, the materials you are used to working with will not suit the patient. In these situations, taking a risk on a new material, spending some time and money, and working through trial and error can not only help your patient, but it can also add another material to your arsenal, explains Wickman.

When considering a new material, the challenge can be coming up with a balance between cost effectiveness and expediency in developing the fabrication process. "Developing the right combination of materials and fabrication procedures can be daunting and impracticable given certain economic factors," says Bernard Hewey, an instructor in the O&P Technician Program at Spokane Falls Community College in Washington. Once a material and its associated fabrication procedures have been established, technicians can expect a learning curve, but with proper training and practice, using advanced materials often becomes commonplace, he adds.

There are countless types of advanced materials-too many to cover in the scope of this article-so we asked industry experts to discuss a few of the most exciting materials technicians are working with today.

Prepreg

Taking the Leap

Working with advanced materials is not unlike a science experiment. You know what you would like to do-you just have to figure out how to go about making it work. Tony Wickman, RTPO, owner of Freedom Fabrication, Havana, Florida, advocates for technicians to use advanced materials whenever they get the chance. He provided the following tips for technicians who are considering taking the leap:

  • Find someone who knows about the material you would like to work with and learn from them.
  • Central fab first!
  • Spend some money. Buy some materials, get out an old mold, and give it a try. Find its flaws.
  • Draw designs. Find the problem with each drawing and come up with solutions.
  • Work in small batches. It is relatively easy to work with smaller batches, and if you like the material you are working with and you are comfortable with it then start with a small investment and slowly work it into your practice.
  • Have a population of people whom you can help, and with whom you can work without involving insurance companies. Make your patient a brace just to see how it works.
  • Remember, everything is a prototype since everything technicians make is a one-of-a-kind device.
  • Understand that there is a potential for failure, but the costs are nominal if you find success.

Prepreg is a general term for one kind of composite which is typically a combination of carbon, fiberglass, and Kevlar® that is "pre-impregnated" with resin and cured in an autoclave, an oven, or at room temperature, explains Jake Godak, RTP, lab manager at CascadeLabs, Chico, California. "Prepreg can be safer than wet-lam because you are not working with an excess quantity of liquid resin to saturate the lay-up," he says. "The correct amount of resin is already applied to the material."

"Prepreg fabrication, which is cheaper than wet-lam, is an effective way to trim the weight of the item by half while making a device that is less noticeable on the patient," says Godak. The only limitations to the material that Godak has found is that it has a textured, matte finish, rather than the glossy finish to which patients are accustomed. "A beauty coat can be applied over the top, but since these devices are usually worn under clothes, this is not really an issue," he adds.

Godak likens working with prepreg to making clothing. The material handles similar to double-sided duct tape so it can be cut and placed exactly where it is needed in the device. It sticks to itself and to the model. It enables the technician to create a device specifically designed for the patient in one layup with areas of rigidity and/or flexibility, he explains.

Godak, who teaches classes on working with prepreg, advises technicians to get some real hands-on time with someone who is qualified to teach prepreg fabrication before attempting it yourself. As with anything new, there is a learning curve associated with prepreg, but the benefits will outweigh the negatives.

Polytol Resin

Otto Bock HealthCare, Minneapolis, Minnesota, introduced its newest product, polytol resin, recently in Europe, and said that it will be available in the United States in the coming months. What makes this material different from the others is it can be used to make a single device (AK and/or BK) that is flexible at the proximal end and rigid at the distal end of the same socket, explains Matt Meier, a former technician who is now a business manager for Otto Bock's Fabrication Services.

"With polytol resin, the technician is able to make a one-shot socket that provides greater comfort to the patient because it does not require a liner and is flexible enough to adapt to changes in the amputee's residual limb," says Meier. The resulting device increases the patient's comfort while enabling smooth ambulation, he adds. The material's characteristics are designed to work well for transfemoral and hip-disarticulation amputees.

As with any new material, technicians need to be educated on how to use it. With polytol resin, the most important factor involves the timing between mixing the material and the lay-up process, says Meier.

Urethane

While most technicians are familiar with urethane and its use in liner manufacturing, Wickman finds that urethane holds a great deal of promise in creating orthoses for his patients. Urethane is used in liners for softness but when embedded with prepreg or other composites it can rival the rigidity of an in-line skate wheel, he says.

"With urethane you can design structures like the human body-soft in some areas and hard in [others]," he says. Using urethane with a composite material such as prepreg creates a lighter, more durable orthoses that is no less work than the traditional wet-lam process, he adds.

"It is our goal to build devices that work like human beings do, and by experimenting with new materials and not being afraid to push the envelope a bit further we can and will create devices that mimic the human body," says Wickman.

Kim M. Norton is a freelance writer based in Mount Laurel, New Jersey.