Current Insights On Custom And Prefabricated Foot Orthoses
Q: How do you evaluate a patient for foot orthotic devices?
A: All three panelists will perform a gait analysis. Russell Volpe, DPM, begins by assessing what he wants the orthosis to accomplish once he decides a CFO is indicated. If control of motion is needed, he will tailor material selection and many of the plaster modifications and prescription items to help accomplish that goal. If Dr. Volpe’s desired goal is accommodation, soft-tissue supplementation or assistance with motion, he will gear material selection and prescription features toward those goals. He also considers other factors like the patient’s weight, the activity or activities the device will be used for and the shoe the device will be worn in, all of which impact device selection and design.
Initially, Howard Kimmel, DPM, will attempt a subjective evaluation. He notes the importance of asking patients what their expectations are for the orthoses, especially if they are being used to prevent the worsening of a current structural deformity like a bunion or hammertoe. Dr. Kimmel tries to make orthoses for the shoes that the patients wear the most but emphasizes patient education on expectations.
“The patients need to know that the orthoses are not going to correct their deformity,” says Dr. Kimmel.
Dr. Kimmel notes that he always asks patients to bring a worn pair of shoes so he can evaluate the wear pattern. He says this helps to correlate his biomechanical exam.
Scott Spencer, DPM, will obtain several measurements: neutral calcaneal stance position, relaxed calcaneal stance position, subtalar joint (STJ) range of motion, ankle joint dorsiflexion in STJ neutral, first metatarsophalangeal joint (MPJ) dorsiflexion with the joint unloaded and forefoot to rearfoot frontal plane measurement with the forefoot maximally loaded under the lateral forefoot and the STJ in neutral position. As he says, this combination helps him obtain a good foundation for the orthotic prescription. He has been starting to use the STJ axis location exam and says it has improved his orthotic prescriptions by better addressing rearfoot control.
In regard to whether a CFO is indicated based upon the chief complaint, Dr. Volpe bases his clinical decision on the history of the complaint and what other treatments or devices the patient has already received. All patients who are candidates for CFOs undergo a full biomechanical static evaluation and dynamic observational gait examination. Dr. Volpe says this helps determine the biomechanical deficits or pathologies that the device must attempt to neutralize or accommodate.
“When I do prescribe CFOs, I make every effort to include them as part of a comprehensive treatment plan that should feature other components and modalities to assist the patients with symptoms and management of the condition,” says Dr. Volpe. “I prefer to use orthoses to return and maintain feet to a more optimal position to prevent recurrence or exacerbation after acute symptomatology has been relieved or is receiving ongoing treatment.”
Q: What are your thoughts on OTC foot orthotic devices?
A: Dr. Kimmel cites several brands that “have done a good job in trying to make an orthotic for the masses.” He says Powerstep’s line has different levels of rigidity and has taken the average measurements of a large number of patients to come up with the arch height and posting. Spenco’s orthotic lines have a plastic bottom and are moldable to a degree using hot water, and Dr. Kimmel says patients have tolerated them very well. Although there is a line of OTC orthoses with an interchangeable metatarsal pad, Dr. Kimmel says most of his patients cannot tolerate them. Dynasteps (Dr. Scholl) are “not a bad device for patients on a budget,” adds Dr. Kimmel. “I always tell my patients that it is like buying glasses over the counter. They might help but it is not their prescription.”
Dr. Spencer will use OTC orthoses but not all types. He prefers devices that incorporate a shell with some motion control. He also prefers an OTC orthosis with a thermoplastic shell, saying the shell permits him more control over adjusting and augmenting the OTC device to best suit the patient.