When I started out as an orthotic technician over 25 years ago, I believed you should always flatten the plantar surface of an AFO mold. That’s what I was taught because it was the conventional wisdom of the day. Then I had the opportunity to work with a group of physical therapy students. I felt secure in talking with the students about my techniques, because I thought I was applying the best we had to offer to the science of rehabilitation.
The students toured the lab and remarked that we were doing some amazing stuff, until they saw how we were modifying our molds. One of the students posed a question, “Why do you flatten the bottom of the foot when you modify the mold?” I answered that we were building mechanical devices, and that flat surface was our foundation. Wasn’t it?
After that, I started to question my fundamental beliefs on how to build a quality device. I was fortunate to have spent my first few years as a technician with some visionary orthotists, and what they taught me made sense, but at this point, I started to think we might be overlooking a very important part in the process, the part where modifications are made so that a device will become an extension of the patient. I noticed when we make arch supports, we never flatten the plantar surface. On the contrary, arch supports mirror the plantar surface. So what’s the difference between making an arch support and an AFO? Why would we think an arch support should take advantage of the curvatures of the plantar surface, but the bottom of an AFO or other orthoses should be flat?
Not long after that encounter with the physical therapy student, I had the opportunity to work with another visionary, a physical therapist and author, who was teaching a class on Neuro-Developmental Treatment (NDT) at that same physical therapy school. She had a test subject for the NDT class and needed a volunteer to fabricate an AFO. Naturally, our lab was offered and I worked one on one with her, and she helped me understand the intricacies of the foot: its bones, nerves, tendons and vascular structures, and how each of these components have their own set of needs. After working with her, I was convinced that technicians must see the foot as the foundation of an orthoses, not the floor! I knew I had to learn more about pedorthics, tone inhibition and neuro-developmental techniques if I wanted to create bio-mechanical devices, devices that fit properly, as well as focus on the specific pathology without causing any collateral damage.
This level of knowledge is beyond the standard education for technicians, but if I am modifying a mold, it’s my responsibility to know about physiology, neurology, and pressure mapping. Every patient who needs a brace has a pathology. Seldom are those pathologies purely orthopedic, there are typically underlying vascular or neuropathic disorders as well. There is no orthopedic solution for a neurological problem.
Technicians need to be aware of this when building a device, and practitioners need to be aware of this when taking a cast. If the cast is taken weight bearing, on a flat surface, much of the plantar data disappears. When a cast can be taken on a foam block, semi weight bearing, or even hand manipulated, that cast takes on a whole new level of function. The surfaces of the foot become much more natural and the load pressures can be more accurately distributed. Neurological inputs can be reduced and deep-tissue weight-bearing techniques can be utilized, and the brace can better fit the patient. One of the issues with casting a patient on a flat surface or flattening the bottom of a mold is that the device created from that mold can cause collateral damage, by creating excessive pressure on at risk tissue, or exacerbating existing problems and putting the surrounding tissues at risk.
No matter the casting technique, I can make a device, but it may not function properly, and it will certainly be less comfortable for the patient. I see these issues most frequently with neuropathic (CROW) walkers and pediatric devices. I’ve worked with many practitioners to help them change their casting technique for these devices, and by doing so, they are seeing better results with their patients.
I believe a technician’s role is to understand and interpret the orthotist’s vision for the patient and make that vision a reality. I also believe the practitioner and technician should work together as a team to make a device that will assist the patient in the best manner possible. If I don’t have an understanding of the nerve structures on the foot, then it’s probable that I won’t make a properly functioning device. Orthoses are not “widgets” that come off an assembly line, they are custom-made bio-mechanical devices that help improve the quality of life for the people who use them.
In order to increase the overall caliber of the rehab team, I suggest that you learn as much as you can about pedorthics, tone inhibition, and neuro-developmental technique. The manipulation of the surfaces of the foot is the foundation of a good lower limb orthosis and these specialized disciplines will give you a good foundation upon which to build your skills.Also published in the November 2009 issue of the O&P Edge. © 2009 O&P Edge