Orthotic modifications are a key benefit of what distinguishes custom devices from prefabricated, off-the-shelf insoles. Accordingly, these panelists discuss modifications that have shown the greatest success in their practices and share pearls on modification strategy, shoe gear and material selection.
Q: What are the most common orthotic modifications you use for an intrinsically-posted orthotic device and why?
David Levine, DPM, C.Ped, points out the uniqueness of how an intrinsically posted device is made. Based on the prescription, Dr. Levine says clinicians would make cast modifications to the positive model in order for the corrections to be reflected in the orthotic device. He adds that forefoot modifications, in his experience, are the easiest to accomplish for intrinsically-posted orthoses. However, Dr. Levine notes that modifying these devices can be more difficult in certain situations.
“When issues are proximal to the metatarsal heads, intrinsically-posted orthotic devices can sometimes be a challenge to modify or adjust,” explains Dr. Levine.
Alan Boehm, DPM, FACFAS says he is more cautious with this type of device. He typically uses an intrinsically-posted device when he is trying to achieve a lower-profile option, like one may employ for dress shoes. Too much modification takes away from that feature, according to Dr. Boehm.
Jane Andersen, DPM agrees, adding she tends to use intrinsically-posted devices when there is a space limitation in shoe gear. When she does modify this type of device, her most common modification is a medial heel skive.
Dr. Levine adds that much of the success of an intrinsically-posted device depends on the materials one uses. He notes that rigid materials are less forgiving and carry a smaller margin of error.
Q: What are the most common orthotic modifications you use for an extrinsically-posted orthotic device and why?
“By far, the most common (for me) would be a rearfoot post,” states Dr. Andersen. “I prefer the extrinsic (rearfoot) post because it has a greater ability to stabilize the device inside the patient’s shoe.”
Dr. Boehm relates that his most commonly employed extrinsic modifications are a lateral wedge or lateral extension.
“Extrinsically-posted orthotic devices offer the most potential for adjustability,” adds Dr. Levine.
He adds that this type of orthotic allows the provider to take more chances when trying to obtain more correction. He continues to explain that the best guarantee for success starts with excellent impressions.
“Device fabrication is entirely dependent upon having the device conform to the foot as intimately as possible,” states Dr. Levine. “Then posting can be an ongoing process.”
Dr. Levine says sanding down posting material and adding material under the arch are simple options podiatrists can employ with an extrinsically-posted device.
He also points out that combining features of both intrinsic and extrinsically-posted devices may be a valuable appproach, depending on the function of the foot, available range of motion, shoe selection, activity level and chief concern.
Q: What are common forefoot modifications that you use in your practice and why?
Dr. Boehm cites offloading to specific metatarsal heads, kinetic wedges, metatarsal padding and Morton’s extension as common forefoot modifications to orthotics in his practice.
“I feel a large percentage of people with first ray pathology suffer from functional hallux limitus and can benefit from increased range of motion (through an orthotic modification),” states Dr. Andersen.
To achieve this, she institutes a reverse Morton’s extension with a cutout for the first metatarsal head in the shell.
Dr. Levine points out that it may be best to make forefoot modifications after the patient has worn the devices for a few weeks. This allows for a better indication of pressure location and how best to address this pressure, according to Dr. Levine. Additionally, he says this approach enables the patient and the provider some time to see what shoes will allow for in terms of the types and thicknesses of materials in the modifications.
For instance, Dr. Levine shares that a running shoe will accommodate a thicker forefoot modification in comparison to a dress shoe. Additionally, an older person with more loss of the plantar fat pad tolerates a softer material in comparison to a younger patient with a plantarflexed metatarsal, who may tolerate a more rigid material.
Q: Do you like using metatarsal pads and under what circumstances do you use them?
The key to success with metatarsal pads, relates Dr. Levine, is accurate placement. He suggests lightly adhering a Poron metatarsal pad to the orthotic with painter’s tape (which does not get in the way or irritate the foot). This will allow the provider or the patient to easily move the pad around to find the optimal position before incorporating it more permanently. Without this precise accuracy, Dr. Levine says the patient may feel a painful lump, for instance, if the pad is too distal.
Dr. Boehm says he uses metatarsal pads often for neuroma/neuritis pain, metatarsalgia, capsulitis, fat pad atrophy, predislocation syndrome and for offloading hyperkeratoses.
Over the past five to 10 years, Dr. Andersen relates increasing her usage of metatarsal pads. Specifically, she finds success when applying them to cases involving neuromas, metatarsalgia and second metatarsal stress syndrome.
Dr. Andersen is in private practice in Chapel Hill, N.C. She is a Past President of the American Association for Women Podiatrists and is board-certified in foot surgery by the American Board of Foot and Ankle Surgery.
Dr. Boehm is in private practice with Foot and Ankle Specialists of the Mid-Atlantic in Holly Springs and Raleigh, N.C. He is board-certified in foot surgery by the American Board of Foot and Ankle Surgery.
Dr. Levine is in private practice with Foot and Ankle Specialists of the Mid-Atlantic in Frederick, Md. He is also the director and owner of Physician’s Footwear, an accredited pedorthic facility, in Frederick, Md., and the owner of New Balance-Frederick.