A Closer Look At Orthotic Technologies And Modifications
The development of new materials and technologies has had an impact on orthotics and biomechanics. These expert panelists discuss the technologies they have found helpful. In particular, they assess the impact of pressure analysis and how it can influence the writing of effective orthotic prescriptions. They also discuss common orthotic modifications and which orthotic materials they use in their practices. Q: How have new materials and technology changed the state of podiatric biomechanics and orthotic therapy? A: Russell Volpe, DPM, calls new materials a “largely positive” development. He notes that employing thinner, more durable materials that resist deformation enables DPMs to utilize more streamlined devices which work with patients’ shoes. “The constant development of something that can do the job better than the materials before has allowed those who work with the best labs and the best products to deliver an increasingly sophisticated device to our patients,” says Dr. Volpe. The frame of reference of podiatrists in biomechanics is moving away from traditional theories of biomechanics, as espoused 30 years ago by Merton Root, DPM, and colleagues, and focusing more on the forces and moments that occur across the foot’s joint axes, according to Kevin Kirby, DPM. Dr. Kirby says the change from “foot deformities” to “foot kinetics” provides podiatrists with a much better comprehension of the mechanical nature of foot and lower extremity biomechanical pathologies that one sees every day in practice. “The major changes in the state of podiatric biomechanics and foot orthosis therapy have not come from new materials and technology but have instead come from gaining a better understanding of foot and lower extremity biomechanics through better research and better podiatric biomechanics theories,” opines Dr. Kirby. Dr. Volpe points out a downside to new technologies, noting that new, technologically advanced materials can increase the cost of the product and subsequently drive up fees. He notes that insurance companies consider these factors and if they do reimburse orthotics, they do so with an attitude of “any device will do,” which leaves DPMs “squeezed between choosing quality and maintaining profit margin.” Although new technology in scanning feet and negative casts can potentially make office and lab operations more efficient and cheaper in the long run, Dr. Volpe notes concerns that such products may cause a loss of quality. He acknowledges DPMs must be assured of the quality of technology before embracing new options. Q: What is your most common in-office orthotic modification? A: Dr. Kirby’s most common modification is grinding a plantar fascial accommodation into the dorsal aspect of the orthosis plate.1 To perform this modification, he says one should grind a very precisely shaped and precisely located furrow into the dorsal orthosis plate that extends along a line from the medial calcaneal tubercle to the first intermetatarsal space area of the orthosis. Dr. Kirby says such a modification can make the difference between orthosis failure and success in many patients. Lawrence Huppin, DPM, says the reverse Morton’s extension is the most common modification he uses in practice. For the most part, he uses 1/8-inch Korex for the extension, which facilitates first ray plantarflexion, decreases first MPJ compression and reduces tension on the plantar fascia. He also commonly employs metatarsal pads, which transfer force off the metatarsal heads. When using metatarsal pads, he suggests gluing top covers only on the posterior half of the orthotic. Doing so allows one to add or adjust the metatarsal pad easily, according to Dr. Huppin. Once the patient is comfortable, he says one can easily glue the cover down the rest of the way. Dr. Volpe does heat molding for prominences and also performs occasional gluing or top cover modifications. However, he does few modifications in the office aside from quick, minor adjustments. He also feels there is better quality control if an orthotic lab makes the modification.